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1.
Cholinesterase (ChE) and acid phosphatase (AP) activities, but not alkaline phosphatase activities, were detected in cytosolic and membrane-bound fractions of adult and infective-stage larvae of levamisole-resistant and levamisole-susceptible Haemonchus contortus. In contrast to other gastrointestinal nematodes, the ChE activity was higher in L3 than in adults and, in both cases, was mainly associated with membranes. ChE activity was inhibited by Triton X-100 and was only detected in membrane-bound fractions when the detergent was removed. Differences between resistant and susceptible L3 were observed in the response to inhibitors (cytosolic fraction) and in the enzymatic content (membrane-bound fraction). Phosphatase activity was detected at acidic pH in all fractions, being higher in the adult than in the L3 stage. In the former, most of the enzyme was localized in the membrane-bound fractions, whereas in the latter it was mainly in cytosolic fractions. This difference could be correlated with the activity in the gut. In inhibition assays, a difference between cytosolic fractions from resistant and susceptible adults was observed in their response to 1 mmol/L tartaric acid.  相似文献   

2.
Passive transfer of immunity to neonatal calves against Taenia saginata was examined. Immune serum immunoglobulins were obtained from cattle inoculated orally with eggs of T. saginata, and from an animal which had been injected intramuscularly with eggs and activated oncospheres of the parasite. Immune colostral immunoglobulins were obtained by local injection of the mammary gland of a preparturient cow using activated oncospheres of T. saginata as antigen.Newborn calves fed the immune serum or colostral immunoglobulins were significantly protected against infection with T. saginata. In addition, more than 80% of the metacestodes in the protected calves showed evidence of degeneration, while only 34 and 27% of the metacestodes showed evidence of degeneration in those animals receiving “normal” control serum and “normal” control colostral immunoglobulins, respectively.  相似文献   

3.
In vitro, carp blood was anticoagulated by using MgSO4 at a final concentration of 22.2 mmol L?1 and sodium citrate at a final concentration of 11.8 mmol L?1. The coagulation times for carp plasma diluted by ion‐free water (1:1), and that of carp plasma to which thrombocytes and small lymphocytes were added, were measured at 23 °C using standard methods, and then contrasted with the coagulation times for plasma obtained from chickens and rabbits. The shapes of the thrombocytes and small lymphocytes, which were either wet mounted or stained with hematoxylin and eosin, were observed under a light microscope. We found that: (i) the coagulation reaction of carp blood was significantly (P < 0.01) accelerated by the addition of ion‐free water; (ii) the three types of blood cells (thrombocytes, small lymphocytes and red blood cells) promoted plasma coagulation to a similar extent (P > 0.05); (iii) in carp Mg2+ plasma and K2C2O4 plasma, the thrombocytes were usually morphologically normal, but many small lymphocytes were destroyed and became aggregated; (iv) in the citrate plasma, thrombocytes were often aggregated, but the small lymphocytes were usually morphologically normal; and (v) the coagulation time for chicken and rabbit plasma was significantly extended by adding ion‐free water.  相似文献   

4.
The radioprotective activity of extracts from the red seaweed Callophyllis (C.) japonica was investigated in mice that underwent whole-body exposure to gamma radiation. A methanol extract of C. japonica and its fractions [hexane, ethyl acetate (EtOAc), butanol and the remaining H2O] were used. Each fraction (100 mg/kg body weight) was administered intraperitoneally (i.p.) 2 times into the BALB/c mice, once at 1 and once at 24 h before exposure to 9 Gray (Gy) of gamma radiation. Pre-irradiation administration of the hexane and EtOAc fractions saved the mice, with their survival rates being greater than 80% at 30 days post-irradiation; the mice that were pretreated with the other fractions showed survival rates lower than 20% over the same time period. To examine the effect of each C. japonica fraction on the survival of intestinal and bone marrow stem cells, the number of intestinal crypts and bone marrow cells in the gamma-irradiated mice were examined. Pre-treatment of mice (i.p., 100 mg/kg body weight at 1 and 24 h before irradiation) with the hexane or EtOAc fraction prior to 6-Gy irradiation significantly protected the number of jejunal crypts and bone marrow cells at 9 days after irradiation. These findings suggest that certain extracts from C. japonica, when they are administered prior to irradiation, play an important role in the survival of irradiated mice, and this is possibly due to the extracts protecting the hematopoietic cells and intestinal stem cells against gamma irradiation.  相似文献   

5.
This study was designed to analyze the reduction potential of three different liquid additives (water, rapeseed oil, and molasses) in three different concentrations mixed with cleaned whole or rolled oats on the generation of airborne particles under standardized laboratory conditions. In addition, the influence of two different drop heights (20 and 40 cm) was analyzed. Airborne particle concentrations were detected online with the gravimetrically measuring analyzer TEOM 1400a that was equipped successively with different inlets to measure the particle fractions PM20, PM10, and PM2.5. The mixing of oats with just 1% (w/w) of each of the liquid additives led to a significant reduction in airborne particle generation in all three particle fractions with respect to the samples without additives (P < .0001). By the addition of 1% oil, a reduction in the PM20 fraction of 90.6% (120.3 μg/m3) could be achieved. The same dosage of water or molasses only resulted in a reduction of 60.4% (504.6 μg/m3) or 69.1% (393.2 μg/m3), respectively. In general, the highest significant reduction in the PM20 fraction was achieved using 3% rapeseed oil: 96.5% as compared with 75.6% for 3% water and 81.9% for 3% molasses. The drop height only had a significant effect on the generation of the PM10 fraction, with it being lower at 20 cm than at 40 cm (P = .0261).  相似文献   

6.
Leopoldamys edwardsi is a species with wide distribution ranges in southern China but is not discussed in studies on geographic variation and species differentiation. We used 2 mitochondrial (Cytb, CO1) and 3 nuclear (GHR, IRBP and RAG1) genes to clarify species phylogeography and geographical differentiation. Maximum likelihood (ML) and Bayesian phylogenetic inference (BI) trees consistently indicated that L. edwardsi is a species complex containing 3 main lineages with high Kimura‐2‐parameter (K2P) divergences (i.e. lineages LN, LS and LHN) found in the northern and southern China and Hainan Island, respectively. The 3 species delimitation methods, automated barcoding gap discovery, Bayesian poisson tree process analysis and Bayesian phylogenetics and phylogeography, consistently supported the existence of cryptic species. Divergence times among the main lineages were inferred to be during the Pleistocene, with LHN/LS split at 1.33 Ma and LN/(LHN+LS) at 2.61 Ma; the diversifications of L. edwardsi complex might be caused by the rapid uplifts of Tibetan Plateau, paleoclimate change and complex topography. The divergence between LHN and LS was probably related to the separation of Hainan Island from the mainland via the formation of the Qiongzhou Strait. Lineages LN and (LS+LHN) likely diverged due to the Wuyi‐Nanling mountain range forming a dispersal barrier. Our results suggested that L. edwardsi complex contains at least 3 distinct species: LHN represents L. hainanensis, endemic to Hainan Island and previously considered as a subspecies L. e. hainanensis; LS represents a cryptic species distributed throughout the southern Chinese continent; and LN represents the nominotypical species L. edwardsi.  相似文献   

7.
Salmonella (S.) Typhimurium and S. Enteritidis are the major causative agents of food-borne illnesses worldwide. Currently, a rapid detection system using multiplex real-time polymerase chain reaction (PCR) has been applied for other food-borne pathogens such as Escherichia coli, Staphylococcus aureus and Streptococcus spp. A multiplex real-time PCR was developed for the simultaneous detection of Salmonella spp., especially S. Typhimurium and S. Enteritidis, in beef and pork. For the specific and sensitive multiplex real-time PCR, three representative primers and probes were designed based on sequence data from Genbank. Among the three DNA extraction methods (boiling, alkaline lysis, and QIAamp DNA Mini Kit), the QIAamp DNA Mini Kit was the most sensitive in this study. The optimized multiplex real-time PCR was applied to artificially inoculated beef or pork. The detection sensitivity of the multiplex real-time PCR was increased. The specificity of the multiplex real-time PCR assay, using 128 pure-cultured bacteria including 110 Salmonella isolates and 18 non-Salmonella isolates, was 100%, 100% and 99.1% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The sensitivity was 100%, 100% and 91.7% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The multiplex real-time PCR assay developed in this study could detect up to 0.54 ± 0.09 and 0.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for beef, 1.45 ± 0.21 and 1.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for pork, respectively, with all conditions optimized. Our results indicated that the multiplex real-time PCR assay developed in this study could sensitively detect Salmonella spp. and specifically differentiate S. Typhimurium from S. Enteritidis in meats.  相似文献   

8.
The anatomy of the spinal cord segments was studied and recorded for the impala. The root attachment lengths were greatest at C3, T10 and L3 cord segment levels in the respective regions. As to the root emergence length the greatest lengths were observed at C7, T]0> L5 and S1 cord segment levels respectively. The interroot interval was longest at C2, T8 and L1 segments respectively. The longest cord segments were C2, T13, L2 and S2 segments. The widest cord segments of their respective regions were C7, T1, L5 and S1 cord segments. As to segment volume C3, T13, L2 and S1 were the most voluminous cord segments in the respective cord regions. Statistical analysis revealed a high correlation among all of the study parameters suggesting a high degree of multicolinearity. Gross anatomical relationships concerning the location of the spinal cord segments with respect to the vertebrae were studied. The cord segments C], Ts–T4 and Li–L3 were within their vertebral limits. In the impala the spinal cord terminated at the midlevel of S4 vertebra.  相似文献   

9.
The purpose of the study was to correlate electroretinogram (ERG) parameters with increasing levels of plasma, erythrocyte and ocular tissue cholinesterase inhibition using the beagle dog as a model for human neurovisual toxicity. The anticholinesterase compound physostigmine was administered at various steady-state intravenous infusion rates based on pharmacokinetic estimates of plasma and red blood cell cholinesterase inhibition. The most sensitive parameter was the b-wave amplitude of the rod response, which was significantly depressed compared to pretreatment at all levels of acute cholinesterase depression. The overall maximal ERG response demonstrated a trend of declining a-and b-wave amplitudes, which corresponded with the increased levels of cholinesterase depression, but these differences were not significant. The depression of the electroretinogram rod and cone amplitudes appeared to parallel plasma cholinesterase inhibition more closely than erythrocyte cholinesterase activity. Ocular tissue cholinesterase activity was significantly depressed in the retina (70%), cornea (60%) and dorsal rectus extraocular muscle (46%). Electroretinography may be a useful physiological tool for evaluating the ocular toxicity of certain chemicals or pharmaceuticals associated with cholinesterase biomarker activity.Abbreviations AChE acetylcholinesterase - Amp amplitude - BuChE butyrylcholinesterase - C p plasma level - C ss steady-state plasma concentration - D L loading dose - e –kt the rate of elimination over time (t) - ERG electroretinogram - k elimination rate constant - Lat latency - MBW metabolic body weight - O1–O5 consecutive oscillatory potential wavelets - PreTx pretreatment - R rate of infusion - R Inf rate of infusion - V d volume of distribution  相似文献   

10.
Seeding native plants into degraded grasslands presents major challenges. Often, seeded species fail to establish and areas become/remain dominated by unwanted plants. We combined herbicides and seeding in former coal mining fields dominated by exotic winter annual grasses (downy brome [Bromus tectorum L.] and Japanese brome [Bromus arvensis L.], hereafter “annual bromes”). The main interest was restoring Wyoming big sagebrush (Artemisia tridentata spp. wyomingensis [Beetle & A. Young] S.L. Welsh, hereafter “big sage”), a very difficult species to restore to North American grasslands. We tested the nonselective herbicide glyphosate and the grass-specific herbicide quizalofop. The summer following herbicide applications and seeding, annual brome cover in controls 22% (CI95% 13%, 36%) was significantly greater (P < 0.03) than in glyphosate 11% (CI95% 5%, 25%) and quizalofop 16% (CI95% 7%, 35%) treatments. At Decker mine, glyphosate increased seeded big sage density (P < 0.04) from 0.76 (CI95% 0.27, 2.11) to 3.05 (CI95% 1.42, 6.56) plants ? m-2 the second summer after seeding. Corresponding increases for Spring Creek mine were from 0.11 (CI95% 0.03, 0.43) to 0.43 (CI95% 0.13, 1.40) plants ? m-2 (P < 0.04). These results were consistent across two experiments initiated in different years. In addition to big sage, our study’s seed mixes contained native grasses and forbs, and herbicide treatments tended to promote establishment of these plant groups. In annual brome-dominated areas of the northern Great Plains, conditions amenable to big sage seedling establishment do not appear entirely uncommon, and herbicides can increase establishment.  相似文献   

11.
In mammalian plasma, cortisol binds to a specific α1-glycoprotein: corticosteroid-binding globulin (CBG). In this study, we measured the protein binding of cortisol by equilibrium dialysis in seven species in which plasma cortisol concentrations varied from 0.02 to 0.05 (ewe, dog, cow) to 0.1 to 0.6 (horse, human, cynomolgus monkey) to reach 1.6 μM (squirrel monkey). No binding of cortisol to CBG was discernible in plasma from squirrel monkey. In all other species examined, we showed that the CBG maximal capacity (Bmax) was 3 (1.7 to 5.2) times more than the plasma cortisol levels, with cow, dog, ewe exhibiting the lowest and cynomolgus monkey exhibiting the highest values. We also noted the existence of a linear relationship between Bmax and the corresponding dissociation constant (Kd), Bmax being systematically 10 (8.5 to 11.8) times more than Kd. The low binding affinity of cortisol assigned to albumin did not differ between species. The free (6 to 14%), CBG-bound (67 to 87%), and albumin-bound (7 to 19%) cortisol fractions calculated from the estimated binding parameters and measured plasma cortisol concentrations were similar within species, except for squirrel monkey, in which half of the cortisol was albumin bound, and the other half remained protein free. Our most appealing finding was that in most species, as much as 68% of plasma CBG remained free of cortisol under physiologic conditions. These results are discussed with respect to the theories concerning the role of CBG in plasma transport and the local delivery of cortisol and free CBG as a proper hormone.  相似文献   

12.
A modified Boyden technique was used to assess the chemotactic activity of unstimulated mouse peritoneal exudate cells in the presence of Trypanosoma brucei. Live parasites, the soluble fraction obtained from disrupted trypanosomes, and specific mouse hyperimmune T. brucei sera were unable to generate chemotactic activity. Complexes of whole parasites and hyperimmune sera gave similar control values, whereas significant activity was obtained using a mixture of live trypanosomes and untreated mouse plasma. Immune complexes prepared by pre-incubation of soluble trypanosome fractions with either untreated or heat inactivated (56°C for 30 min) hyperimmune sera, or with mouse plasma, also resulted in enhanced chemotactic activity.  相似文献   

13.
Lymphocytes from dog thymus and mesenteric lymphnodes have been stimulated in vitro with 3 different mitogens. Culture medium was enriched with either autologous plasma, fetal calf serum or a newly described defined serum substitute. In such cultures the number of surviving and activated cells was quantified by cytofluorometry and the proliferation was assessed by thymidine incorporation. Results obtained with the 3 media were very similar. A significant number of lymphocytes died during the first 42 hours of incubation. There was a tendency toward more surviving cells with fetal calf serum and the serum substitute, whereas more activated (G1) cells and higher thymidine incorporation could be observed with autologous plasma. Furthermore, when results obtained with various mitogen concentrations and from individual dogs were analyzed, a high correlation between “highly activated (G1b) cells and thymidine incorporation was found, i.e. r=0.84 for thymocytes and 0.68 for lymphnode cells. The correlation between all G1 (G1a+b) cells and thymidine incorporation was lower or absent (r=0.02 and 0.55, respectively). It is concluded from these results that the population of G1b cells have received all required signals necessary for proliferation whereas the total G1 cell population also include activated cells, which are not obligatorily undergoing subsequent proliferation  相似文献   

14.
The study objective was to determine if there was a relationship between behavioral and physiological stress measures in sport horses and their performance. Nineteen horses competed in show jumping events (6 housed at the center and 13 transported), while 5 horses at home training served as controls. The competition horses were assigned to “light” (obstacles ≤100 cm) and “difficult” class (obstacles >100 cm). The conflict behaviors (CBs/min) in two rounds were calculated. Total faults were classified as “less faults” (≤one fault) or “more faults” (>one fault). Salivary cortisol concentration (SCC) before the first round (SCC-SP1), 20 minutes (SCC-SP2), and 60 minutes after the second round (SCC-SP3) was measured. The increase (SCC-in) and decrease (SCC-dec) in SCC were calculated. No effect of competition was found. Horses that waited longer for the second round had greater CB (P < .05). Conflict behavior was more frequent in horses from the “more faults” (P = .05) and “difficult” (a tendency; P = .06) classes. No correlation of CB with SCC was found. SCC-SP2 was greater in “more faults” (P < .01) and “transported” (P < .01) horses. Competition increased the SCC (P < .05), whereas SCC-SP2 was greater in less successful horses (P < .05). Transported horses and horses with more faults had the greatest SCC-SP2 and SCC-dec (P < .05). Our results suggest that horses which presented stress response were also less successful in competition. The adoption of effective methods to reduce transport and competition stress could enhance welfare and performance of sport horses during competition.  相似文献   

15.
Rabbits were either actively or passively immunized against Obeliscoides cuniculi and challenged with 5 000 infective larvae (IL). Worm development was inhibited in actively immunized animals and worm egg production was impaired by administration of immune serum. Inhibited fourth stage larvae (L4) from high-level infections (200 000 IL) and normal L4 from low-level infections (4 000 IL) were transferred to actively immunized and normal rabbits. In both instances, large numbers of L4 developed to maturity; however, a significant number of inhibited L4 failed to resume development. Inhibition of larvae resulted in the development of fewer adult male than female worms, and the change in sex ratio was further accentuated in actively immunized recipients. Worm egg production was also reduced in actively immunized rabbits. These data indicate that host immune responses contribute to inhibition of O. cuniculi in rabbits and that worm egg production is also responsive to immunologic control.  相似文献   

16.
Mating results of 5649 pairings taking place in the years 1978 and 1979 were analysed. The average fertility rate for 316 stallions was found to be 85.6%. On average, 17.9 mares were mated to each stallion during the breeding season. The overall fertility (conception) rate was estimated to 82.1%, the apparent fertility rate 81.1% and the numerical productivity rate 78.0%. The sex ratio for the newborn foals was found to be 52.5% males vs 47.5% females, which is significantly different from an equal ratio of the two sexes. The generation interval from parent's birth to birth of offspring, LPO, was estimated to be 9.7 years. The generation intervals for the four different paths were: LSS=8.6, LSD=8.7, LDS=11.4 and LDD=11.6.  相似文献   

17.
A protective antigen was purified from a saline extract of a Type 1 strain of Pasteurella multocida by chromatographic methods, and its chemical and immunological ccharacteristics were studied. Three protein peaks were obtained from crude extract by gel filtration with Sephadex G-200. A bacteria-specific antigen was detected only in the first peak fraction, which, after passing through an immunoadsorbent column to remove any components originating from the growth medium, was adsorbed onto DEAE-cellulose followed by elution with a gradient of NaCl. From the first peak fraction of the gel filtration, 4 protein peaks were obtained, the second and third peaks being the major ones. Carbohydrate/protein ratios of the peak fractions varied from 0.06 to 1.0. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that 2 proteins of molecular weights 44 000 and 25 000 were present in all the fractions. The 4 DEAE-cellulose fractions (DP-1 to DP-4) contained a single antigenically identical material, and induced protective immunity in turkeys against challenge exposure. The second peak fraction from DEAE-cellulose (DP-2) protected turkeys when subcutaneously injected as 2 doses of 10 μg protein with a 14-day interval between doses. The DP-2 fraction induced antibodies in rabbits which formed a single precipitin line against the crude extract. The purified antigen (DP-2) from a Type 1 strain was antigenically distinct from a similar antigen purified from a Type 3 strain; there was no significant cross protection in turkeys between the 2 antigens. These results indicate that protective antigens purified from soluble extracts of a Type 1 or Type 3 strain possess similar physicochemical properties, but that they are immunologically distinct from each other.  相似文献   

18.
This study aimed to obtain information about the types of spirochaetes colonising urban dogs in Thailand, and to investigate their pathogenic potential in a day-old chick model of intestinal spirochaetosis. Spirochaetes were isolated from the faeces of six of 47 (12.8%) healthy dogs and 11 of 104 (10.6%) dogs with diarrhoea. Their biochemical properties and 16S ribosomal DNA sequences were analysed. Four isolates were identified as Brachyspira pilosicoli, three resembled “Brachyspira pulli”, nine clustered with “Brachyspira canis” and one was similar to Brachyspira intermedia. Canine isolates of B. pilosicoli, “B. canis” and “B. pulli”, and control strains of Brachyspira hyodysenteriae, B. pilosicoli and Brachyspira innocens colonised experimentally infected day-old chicks. The chicks did not develop diarrhoea, but were significantly lighter than the non-infected group and those infected with B. innocens after 21 days (P < 0.05). Using immunohistochemistry, spirochaetes were observed covering the surface epithelium and in the crypts of chicks in all three groups challenged with the canine isolates. Variable histopathological changes were seen, with the greatest inflammatory cell infiltration into the lamina propria occurring in the group infected with “B. pulli. Canine “B. canis”, “B. pulli” and B. pilosicoli isolates may have pathogenic potential.  相似文献   

19.
A saline extract of a homogenate of Taenia saginata proglottides was partially purified by gel filtration chromatography on Sephadex G200 or Sepharose 4B and by ion exchange chromatography on DEAE cellulose. Gel filtration produced two distinct fractions with different antigenic properties. The first was of molecular weight of approximately 1,000,000 and contained a high level of activity in the haemagglutination inhibition test. The second fraction of molecular weigh of approximately 100,000 contained most of the immuno-precipitin activity. Other fractions had little or no antigenic activity. Eight fractions were obtained by DEAE cellulose chromatography, of which 4 had detectable antigenic activity. Subsequent rechromatography of fractions obtained by gel filtration on DEAE cellulose produced relatively pure fractions of high antigenic activity, from which small molecular weight contaminants had been removed.  相似文献   

20.
The aim of this study was to evaluate total serum protein concentration measured using biuret reaction and the protein fractions determined using acetate cellulose electrophoresis in Ragusana donkeys (Equus asinus). Blood samples were collected from 68 clinically healthy female donkeys by jugular venipuncture. The serum levels of total proteins were determined using biuret method, and the separation of proteins was performed using acetate cellulose electrophoresis. Coefficients of variation were also calculated for within-assay precision, and were found to be less than 5% for α- and β1-globulins and 8% or less for albumin, β2-, and γ-globulins. A total of five protein fractions were separated and quantified: albumin, α-, β1-, β2-, and γ-globulins. Data obtained from young and adult subjects were compared using the Mann–Whitney U test. Reference intervals (2.5%-97.5% quantiles) were determined for total proteins (50.0-84.0 g/L), albumin (16.2-36.6 g/L), α-globulins (4.85-19.5 g/L), β1-globulins (2.25-10.35 g/L), β2-globulins (3.30-14.85 g/L), γ-globulins (10.0-30.5 g/L), and albumin/globulin ratio (0.41-1.13). In relation to age, statistically significant differences were found in total protein concentration and γ-globulins. The results obtained in the present study contributed to establish reference intervals of serum protein fractions obtained using acetate cellulose electrophoresis in female Ragusana donkeys to be used by practitioners for health control.  相似文献   

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