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81.
A six-day-old Missouri foxtrotter colt was examined because it had had diarrhoea since it was 24 hours old. A diagnosis of colitis, septicaemia, and disruption of the arterial blood flow to the pelvic limbs was made on the basis of clinical and laboratory findings. Despite intensive medical therapy, the foal died 13 hours after being examined. Postmortem examination revealed diffuse fibrinous enteritis with lymphoid necrosis, multifocal fibrinonecrotic typhlocolitis, disseminated intravascular coagulation, and a large occluding thrombus at the aortic termination. The results of bacteriological culturing supported the diagnosis of septicaemia leading to activation of the clotting cascade, disseminated intravascular coagulation, aorto-iliac thrombosis and infarction of the pelvic limbs.  相似文献   
82.
Tea-tree oil (oil of Melaleuca alternifolia) has recently received much attention as a natural remedy for bacterial and fungal infections of the skin and mucosa. As with most naturally occurring agents, claims of effectiveness have been only anecdotal; however, several published studies have recently demonstrated tea-tree oil's antibacterial activity. This study was conducted to determine the activity of tea-tree oil against 58 clinical isolates: Candida albicans (n = 10), Trichophyton rubrum (n = 8), Trichophyton mentagrophytes (n = 9), Trichophyton tonsurans (n = 10), Aspergillus niger (n = 9), Penicillium species (n = 9), Epidermophyton floccosum (n = 2), and Microsporum gypsum (n = 1). Tea-tree oil showed inhibitory activity against all isolates tested except one strain of E floccosum. These in vitro results suggest that tea-tree oil may be useful in the treatment of yeast and fungal mucosal and skin infections.  相似文献   
83.
Ten lines of transgenic mice secreting transmissible gastroenteritis coronavirus (TGEV) neutralizing recombinant monoclonal antibodies (rMAbs) into the milk were generated. The rMAb light- and heavy-chain genes were assembled by fusing the genes encoding the variable modules of the murine MAb 6A.C3, which binds an interspecies conserved coronavirus epitope essential for virus infectivity, and a constant module from a porcine myeloma with the immunoglobulin A (IgA) isotype. The chimeric antibody led to dimer formation in the presence of J chain. The neutralization specific activity of the recombinant antibody produced in transiently or stably transformed cells was 50-fold higher than that of a monomeric rMAb with the IgG1 isotype and an identical binding site. This rMAb had titers of up to 10(4) by radioimmunoassay (RIA) and neutralized virus infectivity up to 10(4)-fold. Of 23 transgenic mice, 17 integrated both light and heavy chains, and at least 10 of them transmitted both genes to the progeny, leading to 100% of animals secreting functional TGEV neutralizing antibody during lactation. Selected mice produced milk with TGEV-specific antibody titers higher than 10(6) as determined by RIA, neutralized virus infectivity by 10(6)-fold, and produced up to 6 mg of antibody per ml. Antibody expression levels were transgene copy number independent and integration site dependent. Comicroinjection of the genomic beta-lactoglobulin gene with rMAb light- and heavy-chain genes led to the generation of transgenic mice carrying the three transgenes. The highest antibody titers were produced by transgenic mice that had integrated the antibody and beta-lactoglobulin genes, although the number of transgenic animals generated does not allow a definitive conclusion on the enhancing effect of beta-lactoglobulin cointegration. This approach may lead to the generation of transgenic animals providing lactogenic immunity to their progeny against enteric pathogens.  相似文献   
84.
The role of endocrine factors as a cause of recurrent spontaneous abortion is controversial. Diabetes mellitus and thyroid disease do not represent a significant risk factor for recurrent pregnancy loss. Luteal-phase defect has been questioned because there are no accurate methods for diagnosis and no convincing evidence of correction with treatment exists. The corpus luteum is an unusual endocrine gland, highly diverse in function and important for successful reproduction in all mammalian species. Much controversy exists about the luteal function in humans and how defects in luteal function affects reproduction. Disagreement has been due to lack of accurate diagnosis and controlled studies to determine whether correction of the luteal-phase defect is worthwhile when treating female reproductive problems. The donor egg recipient model from assisted reproductive technology programs has shown that corpus luteum function can be replaced by estrogen and progesterone administration. The mechanism by which these steroids stimulate a uterus to be receptive to implantation of the embryo is not known. Several proteins produced by the endometrium are candidate markers for uterine receptivity. Further work needs to be done to correlate these markers with subsequent pregnancy outcome. A noninvasive marker for uterine receptivity is ultrasonographic evaluation of the endometrium. Although the sensitivity of this test is high (100%), its specificity is low (only 20% to 60%).  相似文献   
85.
PURPOSE: To determine the effects of 28 d of creatine supplementation during training on body composition, strength, sprint performance, and hematological profiles. METHODS: In a double-blind and randomized manner, 25 NCAA division IA football players were matched-paired and assigned to supplement their diet for 28 d during resistance/agility training (8 h x wk[-1]) with a Phosphagen HP (Experimental and Applied Sciences, Golden, CO) placebo (P) containing 99 g x d(-1) of glucose, 3 g x d(-1) of taurine, 1.1 g x d(-1) of disodium phosphate, and 1.2 g x d(-1) of potassium phosphate (P) or Phosphagen HP containing the P with 15.75 g x d(-1) of HPCE pure creatine monohydrate (HP). Before and after supplementation, fasting blood samples were obtained; total body weight, total body water, and body composition were determined; subjects performed a maximal repetition test on the isotonic bench press, squat, and power clean; and subjects performed a cycle ergometer sprint test (12 x 6-s sprints with 30-s rest recovery). RESULTS: Hematological parameters remained within normal clinical limits for active individuals with no side effects reported. Total body weight significantly increased (P < 0.05) in the HP group (P 0.85 +/- 2.2; HP 2.42 +/- 1.4 kg) while no differences were observed in the percentage of total body water. DEXA scanned body mass (P 0.77 +/- 1.8; HP 2.22 +/- 1.5 kg) and fat/bone-free mass (P 1.33 +/- 1.1; HP 2.43 +/- 1.4 kg) were significantly increased in the HP group. Gains in bench press lifting volume (P -5 +/- 134; HP 225 +/- 246 kg), the sum of bench press, squat, and power clean lifting volume (P 1,105 +/- 429; HP 1,558 +/- 645 kg), and total work performed during the first five 6-s sprints was significantly greater in the HP group. CONCLUSION: The addition of creatine to the glucose/taurine/electrolyte supplement promoted greater gains in fat/bone-free mass, isotonic lifting volume, and sprint performance during intense resistance/agility training.  相似文献   
86.
Longitudinal division of the corpus callosum was performed in six normal beagles to determine surgical morbidity. The corpus callosum was divided sagittally on the midline and the effect on neurological function was determined. Five of six dogs were clinically normal within 14 days or less after surgery. One dog had persistent but improving clinical signs consistent with a forebrain disturbance at 30 days after surgery. Overall, minimal morbidity and no mortality was associated with this surgical procedure. Further study is indicated to determine the efficacy of this surgical treatment for seizure control in dogs with idiopathic epilepsy.  相似文献   
87.
We consider the problem of finding the repetitive structures of a given stringx. The periodu of the stringx grasps the repetitiveness ofx, sincex is a prefix of a string constructed by concatenations ofu. We generalize the concept of repetitiveness as follows: A stringw covers a stringx if there is a superstring ofx which is constructed by concatenations and superpositions ofw. A substringw ofx is called aseed ofx ifw coversx. We present anO(n logn)-time algorithm for finding all the seeds of a given string of lengthn.Partially supported by SERC Grants GR/F 00898 and GR/J 17844, NATO Grant CRG 900293, ESPRIT BRA Grant 7131 for ALCOMII, and MRC Grant G 9115730.Partially supported by MRC Grant G 9115730 and S.N.U. Posco Research Fund 94-15-1112.  相似文献   
88.
89.
Apoptosis or programmed cell death (PCD) is a physiological process critical for organ development, tissue homeostasis and elimination of defective or potentially dangerous cells in complex organisms. Apoptosis permits cell death without a concomitant inflammatory response in the surrounding tissues. The process of apoptosis depends on the reception of multiple extracellular and intracellular signals, integration and amplification of these signals by second messengers and finally, activation of the death effector proteases. Defects in control of apoptotic pathways may contribute to a variety of diseases including cancer, autoimmune and neurodegenerative conditions and AIDS. While many components of the regulatory network controlling apoptosis have been defined, the mechanisms of action and patterns of interaction of these factors remain controversial. This article summarizes some of the known aspects of signaling pathways involved in apoptosis.  相似文献   
90.
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