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131.
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The reactivity of 176 monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, together with 19 internal standards, was analyzed by flow cytometry on 16 different cell types as a means of establishing the proper cell subset for later detailed clustering analyses. The exact CD subset reactivity of the 19 internal standard mAb had been characterized in the First International Swine CD Workshop. The flow cytometric analyses resulted in 40 data sets which were then subjected to statistical clustering using the Leukocyte Typing Database IV (LTDB4) software. As result of this work, 22 clusters were defined. After review of these results, panels of mAb from the defined first round clusters were assigned to cell subsets. The respective mAb in those first round clusters were then distributed to subset group researchers for further examination during the second round of the workshop.  相似文献   
133.
After initial evaluation of the 176 new and 19 control monoclonal antibodies (mAb) submitted to the Second International Swine CD Workshop, 57 were assigned to the T-cell/activation marker subgroup. These 57 mAb were further analyzed using flow cytometry on whole blood lymphocytes, splenocytes, Peyer's patch lymphocytes, in vitro cell lines, broncho-alveolar lavage cells, Con A and PHA blasts, fetal cell populations, and by 2-color flow cytometry against mAb to porcine CD2, CD4, and CD8. Finally, the molecular weights of the target antigens were characterized when possible. As a result of these analyses, 23 mAb were distributed into 7 CD clusters. Newly confirmed mAb assignments included: two CD2; one CD4; two CD5; one wCD6; and one wCD25. Three new mAb were found that reacted with wCD8, one of which defined a new epitope, wCD8c. For the first time, mAb against porcine CD3 were identified, including 6 mAb that reacted with three different epitopes. Several new mAb reacted with antigens whose expression varied depending on the activation state of the test cell. These will require further characterization in order to assign a CD number.  相似文献   
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Three healthy cats were subjected to percutaneous renal biopsy of the left kidney on three occasions at monthly intervals. Three other cats were subjected to three consecutive biopsy attempts on one occasion using the left kidney. Thereafter the six cats were monitored clinically and by means of laboratory analyses of blood and urine until euthanasia four weeks after the last biopsy. Cautious insertion of the biopsy needle in an attempt to avoid over penetration of the kidney resulted in failure to obtain renal tissue on six occasions but in all 12 specimens which did contain renal tissue, glomeruli were present. Major blood vessels were present in two biopsy specimens. At necropsy, radiographic and histological studies demonstrated renal parenchymal and vascular changes in the biopsied kidneys which were similar to but less severe than those produced by a single biopsy attempt. This confirmed that avoidance of damage to major renal vessels is important and suggested that, with care, repeated biopsies need be no more harmful to the kidney than a single biopsy.  相似文献   
136.
The objective of this study was to determine the effect of natural mating stimuli on serum concentrations of LH, testosterone (T) and estradiol-17 beta (E2) in beef bulls. Twenty sexually experienced, yearling beef bulls were bled every 15 min during a 9-h period, 4 h before and 5 h after exposure to estrual females. For exposure, each bull was placed individually in an isolated pen with two restrained estrual heifers for 10 min or until one service was achieved. Timing and number of all behavioral events, including flehmen responses, abortive mounts and services, were recorded for each bull by two independent observers. Of the 20 bulls, 9 bulls mounted and were removed immediately after achieving a service, 8 bulls mounted without achieving a service and 3 bulls exhibited no interest during exposure. Twelve bulls achieved fewer than three and eight bulls achieved three or more flehmen responses during exposure. Postexposure responses in LH, T and E2 were not consistently correlated with number of mounts or presence or absence of a service. However, postexposure LH and T, but not E2, responses were highly correlated with number of flehmen responses achieved (r = .40 to .66; P = .08 to .001). In bulls that achieved three or more flehmen responses, serum LH increased within 30 min after exposure (P = .02) and serum T was increased dramatically within 1 h after exposure (P less than .01), compared with preexposure hormone concentrations, regardless of the number of mounts and regardless of the presence or absence of a service. Natural mating stimuli had no effect on serum E2, and mounting activity alone and mounting that culminated in a service did not necessarily result in increased LH or T in beef bulls. However, number of flehmen responses achieved during exposure to females dramatically influenced postexposure serum LH and T concentrations in beef bulls.  相似文献   
137.
The purpose of this study was to compare the clinical utility of the serum concentration of feline trypsin-like immunoreactivity (fTLI), the plasma and urine concentrations of trypsinogen-activation peptide (TAP), and the ratio of the urine TAP and creatinine concentrations (TAP:Cr) in the diagnosis of feline acute pancreatitis. We used 13 healthy cats and 10 cats with a diagnosis of acute pancreatitis. The mean serum fTLI and plasma TAP concentrations were significantly higher in the cats with acute pancreatitis than in the healthy cats (P < 0.05); the mean urine TAP concentrations and the median urine TAP:Cr ratios were not significantly different. Among the cats examined in this study, there was no benefit of plasma TAP over serum fTLI in the evaluation of suspected acute pancreatitis.  相似文献   
138.
Actinomyces pyogenes from a case of endometritis was used to study the effects of infection of the bovine embryo between days 27 and 41 of pregnancy. From 10(9) to 10(10) washed organisms were introduced into the uterine lumen of four pregnant cows. Two pregnant cows were inoculated with sterile saline and four pregnant cows were treated with cloprostenol. Embryonic death and abortion followed 29 to 144 hours after the inoculation of the live bacteria. The aborted embryos were macerated or clearly degenerating and yielded profuse pure cultures of A pyogenes. Abortion was accompanied by a sustained increase in uterine tone, opening of the cervix, presence of vaginal pus and a vulval discharge and the persistence of the corpus luteum for at least eight days after abortion. Intrauterine inoculation with saline did not affect pregnancy, but embryonic death, abortion and regression of the corpus luteum occurred 66 to 72 hours after the treatment with cloprostenol. The results suggest that A pyogenes is a primary pathogen and is capable of causing embryonic death and abortion.  相似文献   
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