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51.
Stingrays are prominent marine animals; however, there are few published reference values for their blood chemistry and hematology. Twenty-eight southern stingrays (Dasyatis americana) were caught using the bottom trawl nets of fishery-independent boats operated by the South Carolina Department of Natural Resources during June and July 2002 from Winyah Bay, South Carolina, to St. Augustine, Florida. Median values of blood and plasma obtained from live animals promptly after capture are as follows: packed cell volume = 0.22 L/L (22%), total solids (TS) = 56.5 g/L (5.65 g/dl), total protein (TP) = 26 g/L (2.6 g/dl), sodium = 315 mmol/L, potassium = 4.95 mmol/L, chloride = 342 mmol/L, calcium = 4.12 mmol/L (16.5 mg/dl), phosphorus = 1.5 mmol/L (4.7 mg/dl), urea nitrogen = 444 mmol/L (1,243 mg/dl), glucose = 1.69 mmol/L (30 mg/dl), aspartate aminotransferase = 14.5 U/L, creatine phosphokinase = 80.5 U/L, osmolality = 1065 mOsm/kg, and lactate = 3.1 mmol/L. Bicarbonate was less than the low end of the instrument range (5 mmol/L) in all but three samples. Anion gap was negative in all samples. Albumin was less than the low end of the instrument range (1 g/dl) in all except one sample. Osmolality was significantly higher in the rays caught in the southern region. TS and TP values were linearly related to each other, and the equation for the fitted line is TS = (11.61 x TP) + 25.4 (in g/L) [or TS = (1.161 x TP) + 2.54 (in g/dl)]. The reference ranges reported in this study can be used to aid in the management of aquarium stingrays and to create a baseline for health monitoring of the wild Dasyatis spp.  相似文献   
52.
Cryopreservation of ovarian tissue is known to affect follicular survival. Several variables may be responsible for this. Little attention has focused on the effect of the size of the fragment to be cryopreserved. This study was conducted to assess the effect of the size of the tissue on follicular histology after freezing with 1,2-propanediol. Histological evaluations were performed of control and cryopreserved tissue. Fragments were cut 10 × 3 × 2 mm3 (2 mm group) or 10 × 3 × 4 mm3 (4 mm group). Percentages of normal follicles in control fragments cut into 2 and 4 mm slices were 56% and 34%, respectively. The relative risks to obtain normal follicles in the 2 mm and the 4 mm fragments after cryopreservation were 0.63 and 0.47, respectively. Freezing reduced follicle survival to a significantly greater extent in the larger tissue fragments. There is an increased risk of damage to primary and primordial follicles, when the tissue slices are cut with all dimensions larger than 2 mm.  相似文献   
53.
54.
Electrophoretic variations within four enzyme systems (α-esterase, acid phosphatase, malate dehydrogenase and leucine amino peptidase), were studied for various garden and field populations of Chenopodium album. A correlation was found between the degree of polymorphism for the electrophoretic traits and environmental conditions. The amount of phenotypic polymorphism is very high in gardens, intermediate in an untreated and, low in herbicide-treated fields and nil for a triazine resistant population in a maize (Zea mats L.) monoculture. Furthermore, the tetraploid versus hexaploid ratio is higher within garden populations. Higher variability in garden populations is due, in part, to a high proportion of polymorphic phenotypes, and in part to a low effect of selection pressure in such types of habitat. Although there is a difference between phenotypes of populations from acid soils and those from more basic ones, we cannot be sure that the variation of polymorphism is due only to selection.  相似文献   
55.
Background — Elasmobranchs (sharks, skates, and rays) are of commercial, sport, research, and exhibit importance, however, blood chemistry reference values have been determined for few of these species. Objectives — The purpose of this study was to establish plasma biochemistry and PCV reference values for wild bonnethead sharks (Sphyrna tiburo). Methods — Heparinized blood samples were collected from 24 bonnethead sharks at the time of capture in trawl nets off the coast of South Carolina and Georgia. Weight, length, PCV, total solids (TS, by refractometry), and plasma biochemical analyses were done using standard techniques. Wilcoxon rank‐sum and Kendall tau b tests were used to compare values by animal size, boat and sex; 1–way ANOVA was used to compare TS and total protein (TP) concentrations. Results — Median (quartiles; minimum‐maximum) values were as follows: PCV 22% (22%, 26%; 17–28%), TS 6.3 (6.0, 6.8; 5.8–7.5) g/dL, total protein 2.9 (2.7,3.4; 2.2–4.3) g/dL, albumin 0.4 (0.4,0.4; 0.3–0.5) g/dL, globulins 2.6 (2.3,3.0; 1.9–3.8) g/dL, sodium 282 (279, 285; 273–292) mmol/L, potassium 7.3 (6.4, 7.9; 5.7–9.2) mmol/L, chloride 290 (285, 296; 277–304) mmol/L, total CO2 3 (2, 4; 0–5) mmol/L, calcium 16.8 (16.2,17.4; 15.8–18.2) mg/dL, phosphorus 8.8 (7.5,10.0; 5.9–12.7) mg/dL, urea nitrogen 1004 (986, 1028; 944–1068) mg/dL, creatinine <0.1 mg/dL, glucose 184 (165, 191; 155–218) mg/dL, aspartate aminotransferase 42 (33, 66; 15–132) U/L, lactate dehydrogenase <5 U/L, creatine kinase 82 (47, 233; 18–725) U/L, and osmolality 1094 (1078,1111; 1056–1139) mOsm/kg. No differences based on sex were detected. TS and total TP values were related by the fitted line TS = (1.006 × TP) + 3.318. Conclusions — Values reported here will be useful for evaluating the health status of bonnetheads in wild and captive research conditions and in exhibits.  相似文献   
56.
从肿头综合征鸡分离出产Vero毒素E.coli   总被引:1,自引:1,他引:0  
本研究从哈尔滨郊区某鸡场肿头综合征( S H S)鸡分离出 3 株血清型为 O78 的埃希氏大肠杆菌( E.coli),从鞍山 S H S病料分离出 1 株血清型为 O8 的 E.coli。并证实这 4 株 E.coli 能够对 Vero 细胞产生毒性作用,与产 Vero 毒素的 E.coli一致。对哈尔滨市郊 S H S病鸡做病理组织学观察,主要变化为头部皮下组织,头盖骨气室及鼻粘膜下纤维素性化脓性炎症,水肿和大肠杆菌性肉芽肿,心、肝、肾等器官炎症变化并有大量异嗜性粒细胞和细菌团块。  相似文献   
57.
Summary The paper deals with studies on the dynamics of Carbaryl residue loss on apples, plums and peaches.The initial toxicant deposit ranges between 8 and 13 ppm on peaches, 2, 3 and 3, 4 ppm on apples and up to 1.5 ppm on plums. According to the dynamics of Carbaryl residue loss on fruit results a rest period of 2 days for plums, 7 days for apples and 21 days for peaches, on admitting a 2 ppm tolerance.
Zusammenfassung Unter Berücksichtigung der Witterungsbedingungen wurde die Geschwindigkeit des Abbaus von Carbaryl-Rückständen bei Äpfeln, Pflaumen und Pfirsichen untersucht. Die anfängliche Höhe der Rückstände betrug bei Pfirsichen zwischen 8 und 13 ppm, bei Äpfeln 2,3 und 3,4 ppm und bei Pflaumen bis zu 1,5 ppm. Wird eine Toleranz von 2 ppm zugrundegelegt, ergibt sich entsprechend der Abbau-Geschwindigkeit von Carbaryl bei Früchten eine Wartezeit von 2 Tagen bei Pflaumen, 7 Tagen bei Äpfeln und 21 Tagen bei Pfirsichen.

Resume On présente de données sur la dynamique de la dégradation des résidus de Carbaryl sur pommes, prunes et pêches. Le résidu initial atteint 8–13 ppm chez les pêches, 2,3–3,4 ppm chez les pommes et 1,5 ppm chez les prunes.De cette dynamique de la dégradation des résidue sur fruits il résulte que pour les prunes l'intervalle de pause de deur jours, pour les pommes de 7 jours et pour les pêches de 25 jours dans les conditions climatiques de Roumanie.


Presented at the Congress of Chemistry in Agriculture, Bratislava, Sept. 1969.  相似文献   
58.
OBJECTIVE: To determine the cause of an epidemic of blindness in kangaroos. DESIGN AND PROCEDURES: Laboratory examinations were made of eyes and brains of a large number of kangaroos using serological, virological, histopathological, electron microscopical, immunohistochemical methods, and PCR with cDNA sequencing. In addition, potential insect viral vectors identified during the disease outbreak were examined for specific viral genomic sequences. SAMPLE POPULATION: For histopathological analysis, 55 apparently blind and 18 apparently normal wild kangaroos and wallabies were obtained from New South Wales, Victoria, South Australia, and Western Australia. A total of 437 wild kangaroos and wallabies (including 23 animals with apparent blindness) were examined serologically. RESULTS: Orbiviruses of the Wallal and Warrego serogroups were isolated from kangaroos affected with blindness in a major epidemic in south-eastern Australia in 1994 and 1995 and extending to Western Australia in 1995/96. Histopathological examinations showed severe degeneration and inflammation in the eyes, and mild inflammation in the brains. In affected retinas, Wallal virus antigen was detected by immunohistochemical analysis and orbiviruses were seen in electron microscopy. There was serological variation in the newly isolated Wallal virus from archival Wallal virus that had been isolated in northern Australia. There were also variations of up to 20% in genotype sequence from the reference archival virus. Polymerase chain reactions showed that Wallal virus was present during the epidemic in three species of midges, Culicoides austropalpalis, C dycei and C marksi. Wallal virus nucleic acid was also detected by PCR in a paraffin-embedded retina taken from a blind kangaroo in 1975. CONCLUSION: Wallal virus and perhaps also Warrego virus are the cause of the outbreak of blindness in kangaroos. Other viruses may also be involved, but the evidence in this paper indicates a variant of Wallal virus, an orbivirus transmitted by midges, has the strongest aetiological association, and immunohistochemical analysis implicates it as the most damaging factor in the affected eyes.  相似文献   
59.
抗旱保水剂在紫花苜蓿种植中应用的试验报告   总被引:6,自引:0,他引:6  
用抗旱保水剂对土壤和紫花苜蓿种子处理后,进行种植试验。结果表明,使用抗旱保水剂出苗每平方米较对照地增加24.25株,存苗增加35.62株,苗高平均增加0.32cm,根长平均增长0.69cm,鲜草每平方增加0.41kg。  相似文献   
60.
AIMS: To investigate the production responses and cost-benefit of administering a controlled-release anthelmintic capsule (CRC) to pregnant yearling ewes prior to lambing.

METHODS: Yearling ewes from two commercial sheep flocks (A, n=489; B, n=248) in the North Island of New Zealand were enrolled in the study. Prior to lambing, CRC containing albendazole and abamectin were administered to half the ewes while the other half remained untreated. Ewe liveweights and body condition scores were measured prior to lambing, at weaning and, for Flock B, prior to subsequent mating. Lambs were matched to dams shortly after birth and the weight and number of lamb weaned per ewe were determined. A cost-benefit analysis was undertaken for Flock B considering the increased weight of lamb weaned per ewe, and the weight of ewes at the next mating and the benefit in terms of lambs born.

RESULTS: The mean weight at weaning of treated ewes was greater for treated than untreated ewes by 2.76 (95% CI 0.64–4.88)?kg in Flock A (p<0.001) and 2.35 (95% CI ?0.41–5.12)?kg in Flock B (p=0.003); the weight of lamb weaned per ewe was greater for treated than untreated ewes by 1.43 (95% CI ?0.71 to –3.49)?kg in Flock A (p=0.041) and 3.97 (95% CI 1.59–6.37)?kg in Flock B (p<0.001), and ewe liveweight prior to subsequent mating was greater for treated than untreated ewes in Flock B by 4.60 (95% CI 3.6–5.6)?kg (p<0.001). There was no difference in the percentage of lambs reared to weaning between treated and untreated ewes in either flock (p>0.8). The overall cost-benefit of treatment for Flock B was NZ$9.44 per treated ewe.

CONCLUSIONS AND CLINICAL RELEVANCE: Pre-lambing CRC administration to yearling ewes resulted in increased ewe weaning weights and weight of lamb weaned in both the flocks studied. There was an economic benefit in the one flock where this was assessed.  相似文献   

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