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排序方式: 共有249条查询结果,搜索用时 15 毫秒
91.
NS Matthews SW Erickson GS Light MR Slater SM Hartsfield 《Veterinary anaesthesia and analgesia》1995,22(1):25-30
The effects of tolazoline (4.0 mg/kg iv) antagonism of detomidine (0.02 mg/kg iv) were evaluated in isoflurane-anaesthetised, ventilated ponies. Each of 6 ponies received both tolazoline and saline treatment during separate anaesthetic episodes only (no surgery was performed). Detomidine administration produced an increase in blood pressure, decrease in heart rate and decrease in PaO2 Tolazoline treatment transiently increased heart rate while blood pressure returned to baseline after both treatments. Arterial oxygenation decreased further after tolazoline treatment while oxgenation recovered towards baseline with saline treatment. No other cardiopulmonary effects were detected. Recovery from anaesthesia tended to be more rapid when detomidine was antagonized. The potential benefit of antagonizing detomidine-induced bradycardia with tolazoline, during isoflurane anaesthesia should be weighed against the potential to produce a decrease in arterial oxygenation. The mechanism for this effect is not clear. 相似文献
92.
Sylvain De Guise Karen Erickson Myra Blanchard Lisa DiMolfetto Heather D Lepper Janice Wang Jeffrey L Stott David A Ferrick 《Veterinary immunology and immunopathology》2002,84(3-4):209-221
CD2 is a pan-T cell marker, while CD19 and CD21 are important molecules in signal transduction of B lymphocytes. CD19 and CD21 are both present on mature B cells, while CD19 is also present in developing B cells and plasma cells. Monoclonal antibodies (mAbs) against cetacean lymphocyte putative homologues to CD2 (two different antibodies), CD19 and CD21 were characterized. The proteins immunoprecipitated were as follows: F21.I (putative anti-CD2), 43 and 59kDa; F21.B (putative anti-CD19), 83 and 127kDa; F21.F (putative anti-CD21), 144kDa. The second putative anti-CD2 (F21.C) selectively inhibited the binding of F21.I. Both the putative anti-CD2 (T cell markers) stained T-cell zones on lymph node sections, while both the B cell markers (putative CD19 and CD21) stained B-cell zones. F21.B and F21.F were absent from thymus single cell suspension but labeled 63 and 65% mesenteric lymph node lymphocytes, respectively, while both F21.C and F21.F were present on 100% thymocytes and fewer lymph node lymphocytes. B and T cell markers were mutually exclusive on double labeling using flow cytometry. These mAbs are foreseen as possible valuable diagnostic and research tools to assess immune functions of captive and wild cetaceans. 相似文献
93.
Summary A cat with weight loss, pyrexia and recurrent lethargy and depression was found to have pleural and peritoneal eosinophilic effusions, peripheral eosinophilia, eosinophilic lymphadenitis and a massively enlarged mesenteric lymph node. Visceral mast cell neoplasia was diagnosed after histopathological examination of a biopsy of the mass. Palliative chemotherapy was attempted unsuccessfully and the cat was euthanased. 相似文献
94.
An economic model concerning the value of using prostaglandin (PG) in dairy cows with nondetected estrus was developed. Considering numerous and varied assumptions, it was more profitable to treat cows with PG and to breed the cows at a detected estrus than it was not to treat the cows and to wait to breed the cows at a detected estrus. Generally, using timed artificial insemination, it was also more profitable to breed PG-treated cows than it was not to use PG. However, timed insemination was less profitable than was breeding PG-treated cows by artificial insemination at a detected estrus. 相似文献
95.
Extensive destructive and erosive lesions of the eye lids may be the result of neoplasia, severe trauma, or inflammation. Surgical repair requires blepharoplastic procedures to restore the lid integrity and maintain a functionally sighted globe. The use of the rhomboid advancement flap is illustrated for the repair of lid defects involving destruction of 50% or more of the lid tissue. 相似文献
96.
Chen CI King DP Blanchard MT Hall MR Aldridge BM Bowen L Stott JL 《Veterinary microbiology》2007,120(3-4):320-327
Epizootic bovine abortion (EBA), or foothill abortion as it has often been termed, is a tick-borne disease of pregnant cattle recognized in California, Nevada and Oregon. The primary objective of this study was to better define the relationship of a novel deltaproteobacterium, the putative etiological agent of EBA (aoEBA), with the Pajaroello tick (Ornithodoros coriaceus Koch), the recognized vector of EBA. Three developmental stages of O. coriaceus (larva, nymph, and adult) were collected from five locations in California, Nevada and Oregon. A polymerase chain reaction (PCR), developed for detection of aoEBA, was applied to DNA extracted from ticks. Southern blotting of the PCR products increased the number of ticks determined to be carrying the bacteria by seven-fold, suggesting the majority of infected ticks carry relatively low numbers of the pathogen. An effort was made to determine if an artificial blood meal would stimulate replication of the bacterial pathogen, thereby increasing the frequency in which aoEBA could be identified; no statistically significant effect was evident. The number of ticks determined to be carrying aoEBA varied with geographic location and ranged from 5 to 20%. aoEBA was found in both adults (12% of the males and 12% of the females) and nymphs (13%) but not larvae. Comparative analysis of dissected ticks provided strong evidence that the salivary gland was the most common location of aoEBA in field-collected ticks. No significant correlations were identified between the frequency of infection and tick weight, suggesting that increasing tick age and increased number of blood meals did not increase infectivity. 相似文献
97.
98.
99.
Biomimetic Pathways for Assembling Inorganic Thin Films 总被引:3,自引:0,他引:3
IA Aksay M Trau S Manne I Honma N Yao L Zhou P Fenter PM Eisenberger SM Gruner 《Science (New York, N.Y.)》1996,273(5277):892-898
Living organisms construct various forms of laminated nanocomposites through directed nucleation and growth of inorganics at self-assembled organic templates at temperatures below 100°C and in aqueous solutions. Recent research has focused on the use of functionalized organic surfaces to form continuous thin films of single-phase ceramics. Continuous thin films of mesostructured silicates have also been formed on hydrophobic and hydrophilic surfaces through a two-step mechanism. First, under acidic conditions, surfactant micellar structures are self-assembled at the solid/liquid interface, and second, inorganic precursors condense to form an inorganic-organic nanocomposite. Epitaxial coordination of adsorbed surfactant tubules is observed on mica and graphite substrates, whereas a random arrangement is observed on amorphous silica. The ability to process ceramic-organic nanocomposite films by these methods provides new technological opportunities. 相似文献
100.
DO Gough AG Kosovichev J Toomre E Anderson HM Antia S Basu B Chaboyer SM Chitre J Christensen-Dalsgaard WA Dziembowski A Eff-Darwich JR Elliott PM Giles PR Goode JA Guzik JW Harvey F Hill JW Leibacher MJPFG Monteiro O Richard T Sekii H Shibahashi M Takata MJ Thompson S Vauclair SV Vorontsov 《Science (New York, N.Y.)》1996,272(5266):1296-1300
Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of chemical inhomogeneity that is too severe in the model, perhaps owing to inaccurate modeling of gravitational settling or to neglected macroscopic motion that may be present in the sun. Accurate knowledge of the sun's structure enables inferences to be made about the physics that controls the sun; for example, through the opacity, the equation of state, or wave motion. Those inferences can then be used elsewhere in astrophysics. 相似文献