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排序方式: 共有114条查询结果,搜索用时 31 毫秒
1.
A new nematode species, Rhabdochona longleyi sp. n. is described from the intestine of two species of blind catfishes, Trogloglanis pattersoni Eigenmann (type host) and Satan eurystomus Hubbs et Bailey (both fam. Ictaluridae, Siluriformes) from the subterranean waters (artesian wells penetrating San Antonio pool of Edwards Aquifer) of Texas, USA. It is characterized largely by the presence of only six anterior teeth in the prostom, simple deirids, by the shape and length of spicules (0.42 to 0.50 mm and 0.093-0.102 mm), shape of the tail tip (rounded), and by filamented eggs. R. longleyi probably adapted to the environment of the aquifer by utilizing available troglobitic crustaceans instead of aquatic insects as an intermediate host. 相似文献
2.
Objective This study documents the results of non-surgical treatment and treatment by superior check desmotomy in Thoroughbred racehorses with superficial digital flexor (SDF) tendonitis. Design A prospective study was made of 124 thoroughbred racehorses with unilateral or bilateral SDF tendonitis. Procedure The flexor tendons were assessed by physical and ultrasonographic examination before treatment, and the lesions detected in affected tendons were characterised according to lesion type, length and cross-sectional area. Ninety three horses were managed non-surgically and 31 by superior check desmotomy. Recurrent or new injuries were defined as injuries affecting a previously injured superficial digital flexor tendon, the contralateral SDF tendon, or the suspensory ligament (interosseous muscle) in either forelimb. Results No statistically significant difference was found in ultrasonographic lesion severity between treatment groups. Horses managed by superior check desmotomy were 1.3 times more likely to complete five or more races than horses managed non-surgically (95% confidence limits 0.93–1.82). Horses treated surgically were 1.2 times more likely to develop recurrent or new injuries after returning to training than horses managed non-surgically (95% CL 0.95–1.55). Horses under-going superior check desmotomy were 5.5 times more likely to develop suspensory desmitis than horses treated non-surgically (95% CL 1.13–26.4). There was no difference in the time to recurrent or new injury between treatment groups. Conclusion There was no statistically significant difference between treatment groups in the proportions of horses able to complete five or more races after an episode of superficial digital flexor tendonitis. Superior check desmotomy did not appear to offer an advantage over non-surgical treatment in preventing recurrent or new injuries in Thoroughbred racehorses. Horses undergoing superior check desmotomy appeared to be at greater risk of developing suspensery ligament injuries than horses managed non-surgically. 相似文献
3.
Differences in cathepsin B + L and calcium-dependent protease activities among breed type and their relationship to beef tenderness 总被引:2,自引:0,他引:2
M H Johnson C R Calkins R D Huffman D D Johnson D D Hargrove 《Journal of animal science》1990,68(8):2371-2379
Activities of acidic proteases (cathepsin B + L) and neutral, calcium-dependent proteases (CDP) were quantified to determine whether differences in proteolytic activity could explain differences in meat tenderness among breed types. Steers (n = 32) of known percentage Angus (A) and Brahman (B) breeding were used to establish differences in meat tenderness (A; 3/4A-1/4B; 1/2A-1/2B; 1/4A-3/4B). Samples were removed from the longissimus muscle within 1 h postmortem and within 2 h were frozen for subsequent determination of cathepsin B + L, CDP-I, CDP-II and CDP-inhibitor activities. Warner-Bratzler shear (WBS) was assessed after 1, 5 and 10 d of postmortem aging. Taste panel evaluations, conducted on steaks that were subjected to 5 d of aging, detected no differences. At d 1, WBS did not differ among breed types; however, by d 10 of aging, steaks from Angus steers were more tender (P less than .05) than steaks from 1/2B and 3/4B steers. The Angus and 1/4B steaks had significantly more (P less than .05) cathepsin B + L activity than the 3/4B. The CDP had no relationship with WBS; however, CDP-inhibitor was positively related to d-1 WBS (r = .41, P less than .05). Cathepsin B + L activity was negatively related to WBS at d 10 (r = -.44, P less than .05). These data suggest that differences in meat tenderness among breed types may be explained partially by differences in proteolytic enzyme activity. 相似文献
4.
Brandon L. Plattner Elise Huffman Douglas E. Jones Jesse M. Hostetter 《Veterinary immunology and immunopathology》2014,157(1-2):12-19
Johne's disease (JD) is a costly intestinal disease of ruminants caused by Mycobacterium avium subspecies paratuberculosis (Map), which is transmitted to perinatal calves by the fecal-oral route. Disease control efforts focus on identification and culling of infected cattle from herds; therefore failure to identify animals early is a major obstacle to reducing transmission. Development of host immunity during early JD remain incompletely characterized so detecting subclinical JD using immunologic techniques is a substantial challenge in the field. Development of a test with high sensitivity and specificity is a major research goal with significant implications for the cattle industry. The objectives of this study were to compare early Map-specific T lymphocyte responses in naive, experimentally Map infected and Map vaccinated calves using a subcutaneous matrigel biopolymer-based assay. We examined the phenotype of recruited lymphocytes and local interferon gamma (IFNγ) production within subcutaneously placed matrigel containing Map antigen 30 days after experimentally induced intestinal Map infection or Map vaccination. We show that IFNγ-secreting CD4+ T cells are recruited to matrigel sites in vaccinated but not infected or naïve calves. γδ T cells recruited to matrigel sites of Map-infected calves were mostly WC1-, while γδ T cells recruited to matrigel sites of Map-vaccinated calves were predominantly WC1+. IFNγ at matrigel sites was a discriminating factor between infected calves, naïve calves and vaccinated calves. These data contribute to our understanding of early anti-Map immunity, and may be useful for detecting early intestinal Map infections in calves or for enhancing our ability to discriminate between Map-infected and Map-vaccinated calves. 相似文献
5.
6.
Dickerson RR Huffman GJ Luke WT Nunnermacker LJ Pickering KE Leslie AC Lindsey CG Slinn WG Kelly TJ Daum PH Delany AC Greenberg JP Zimmerman PR Boatman JF Ray JD Stedman DH 《Science (New York, N.Y.)》1987,235(4787):460-465
Acid deposition and photochemical smog are urban air pollution problems, and they remain localized as long as the sulfur, nitrogen, and hydrocarbon pollutants are confined to the lower troposphere (below about 1-kilometer altitude) where they are short-lived. If, however, the contaminants are rapidly transported to the upper troposphere, then their atmospheric residence times grow and their range of influence expands dramatically. Although this vertical transport ameliorates some of the effects of acid rain by diluting atmospheric acids, it exacerbates global tropospheric ozone production by redistributing the necessary nitrogen catalysts. Results of recent computer simulations suggest that thunderstorms are one means of rapid vertical transport. To test this hypothesis, several research aircraft near a midwestern thunderstrom measured carbon monoxide, hydrocarbons, ozone, and reactive nitrogen compounds. Their concentrations were much greater in the outflow region of the storm, up to 11 kilometers in altitude, than in surrounding air. Trace gas measurements can thus be used to track the motion of air in and around a cloud. Thunderstorms may transform local air pollution problems into regional or global atmospheric chemistry problems. 相似文献
7.
O'Connell MJ Bachilo SM Huffman CB Moore VC Strano MS Haroz EH Rialon KL Boul PJ Noon WH Kittrell C Ma J Hauge RH Weisman RB Smalley RE 《Science (New York, N.Y.)》2002,297(5581):593-596
Fluorescence has been observed directly across the band gap of semiconducting carbon nanotubes. We obtained individual nanotubes, each encased in a cylindrical micelle, by ultrasonically agitating an aqueous dispersion of raw single-walled carbon nanotubes in sodium dodecyl sulfate and then centrifuging to remove tube bundles, ropes, and residual catalyst. Aggregation of nanotubes into bundles otherwise quenches the fluorescence through interactions with metallic tubes and substantially broadens the absorption spectra. At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap-selective protonation of the side walls of the tube. This protonation is readily reversed by treatment with base or ultraviolet light. 相似文献
8.
Aspects of bacteriology and endocrinology of cows with pyometra and retained fetal membranes 总被引:4,自引:0,他引:4
J D Olson L Ball R G Mortimer P W Farin W S Adney E M Huffman 《American journal of veterinary research》1984,45(11):2251-2255
In an effort to clarify the pathogenesis of pyometra, 20 cows with retained fetal membranes and 20 without, but with contemporary calving dates were studied. They were palpated and their uteri were subjected to sample collections for bacteriologic cultural examinations twice weekly for 4 weeks. Blood samples were obtained each day and evaluated for serum progesterone concentration. Three cows without and 3 with retained fetal membranes developed pyometra during the study, resulting in 3 groups designated control (CON), cows with retained fetal membranes (RFM), and cows with pyometra (PYO). Bacterial isolations occurred less frequently in the CON group than in the PYO and RFM groups. Growth patterns of bacteria also varied between groups. Coliform and incidental bacteria disappeared from the uterus of the PYO group by the end of the 3rd week. In contrast, heavy growth of Corynebacterium pyogenes and gram-negative anaerobic bacteria developed during this same period in the PYO group. In cows with pyometra, the significant persistent pathogenic bacteria recovered were C pyogenes and gram-negative anaerobic bacteria, especially Fusobacterium necrophorum and Bacteroides melaninogenicus. Anaerobic bacteria were isolated simultaneously with C pyogenes in most cows of the PYO group, but less often in CON and RFM groups, and highest growth levels were present near the time of ovulation. Clinically, pyometra usually developed about 10 days after observation of concurrent ovulation and high growth levels of C pyogenes and gram-negative anaerobic bacteria. A hypothesis is presented for development of pyometra in the cow. 相似文献
9.
L A Vasquez L Ball B W Bennett G P Rupp R Ellis J D Olson M H Huffman 《American journal of veterinary research》1983,44(8):1553-1557
The therapeutic efficacy of a Campylobacter fetus subsp venerealis bacterin was determined in experimentally infected bulls. Ten of twelve 5-year-old Angus bulls became infected after being infused intrapreputially with C fetus subsp venerealis. Of the 10 bulls, 6 were vaccinated with 5 ml of C fetus subsp venerealis vaccine on 2 occasions 4 weeks apart. Preputial washings of the vaccinated bulls were culturally negative by the 8th week after primary vaccination. None of the 18 heifers exposed to the vaccinated bulls became infected. The 4 infected, nonvaccinated bulls remained culturally positive to C fetus (P less than 0.002), and each bull infected at least 1 heifer (P less than 0.001). Two noninfected, nonvaccinated bulls remained culturally negative and did not infect any heifer. The 4 infected, nonvaccinated bulls were then vaccinated. Two bulls remained infected 9 weeks after primary vaccination, as determined by the virgin heifer test and cultural examination of preputial washings. Serologic data from 7 sampling periods were different (P less than 0.001) for vaccinated vs nonvaccinated bulls at 4 (against K antigen) or 6 (against O antigen) weeks after primary vaccination. Vaccination was effective in eliminating the infection in most of the infected bulls, but cannot be recommended as the sole measure of control in infected herds. 相似文献
10.