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991.
Embolic pulmonary aneurysms in yearling feedlot cattle   总被引:2,自引:0,他引:2  
Throughout all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. Of 1,988 cattle necropsied, 25 (1.3%) had ruptured pulmonary aneurysms and an additional 4 had gross pulmonary emboli without rupture. The emboli originated from thrombi in the caudal vena cava where that vessel closely applies to the left border of the liver and where parenchymal abscesses had developed. The emboli had lodged in the pulmonary artery, weakened its wall, and led to saccular aneurysms. Infection weakened and blood pressure ruptured the saccule and opened the adjacent bronchi. Extravasated blood dissected the tunica adventitia, formed hematomas, poured into the bronchus, and was expelled from the larynx. A portion was swallowed into the rumen, and some was coughed and blown from the nose and mouth. Deaths were attributed to exsanguination and pulmonary incapacitation.  相似文献   
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Previous experiments in this laboratory demonstrated a progressive decrease in cell-mediated cytotoxicity (CMC) against allogeneic tumor cells by immune spleen cells from mice repeatedly immunized with those tumor cells. In the present study, immune spleen cells, obtained at specified intervals during the course of multiple immunizations of BALB/c mice with EL-4 lymphoma cells, were tested for CMC against EL-4 target cells pretreated with anti-EL-4 serum which had been obtained from singly or repeatedly immunized animals. Cytolysis of EL-4 cells was measured by a 51Cr-release assay. The results indicate that blocking of CMC in an allogeneic tumor model may occur by two pathways. First, antigen or antigen-antibody complexes present in the immunized animal may bind in vivo to the antigen receptor sites of of sensitized effector cells that are used in the in vitro CMC assay, thereby blocking their interaction with tumor cells. Second, immune serum that is added to the in vitro CMC assay may contain highly avid antibodies, as well as antigen-antibody complexes, that bind to tumor cells and thereby block interaction with sensitized effector cells. The identification of these elements may be of prognostic significance in certain clinical situations.  相似文献   
994.
Acid phosphatase (EC 3.1.3.2) isoenzyme profiles of extracts of splenic tissue and serum from patients with Gaucher's disease were measured by a mini-column ion-exchange chromatographic method [Clin. Chem., 23, 000 (1977)]. Diagnosis of Gaucher's disease in the five patients studied was confirmed by demonstrating decreased (2.3 to 4.1% of normal) glucocerebrosidase activity in the spleen. With p-nitrophenyl phosphate as substrate, increased acid phosphatase activity (three-to eight-fold normal) was demonstrated in spleen tissue from Gaucher;s disease patients; isoenzyme profiles by the ion-exchange column technique showed acid phosphatase isoenzyme 5 to be the predominant isoenzyme. Comparison of acid phosphatase isoenzyme profiles from patients with Gaucher's disease and prostatic carcinoma revealed distinct differences in the activities of isoenzymes 2 and 5. The isoenzyme-5 measurement thus appears to provide a diagnostic test for Gaucher's disease that can be done reapidly and easily in the routine clinical chemistry laboratory.  相似文献   
995.
The neutral lipids of the skin from the feet of turkey poults fed a biotin supplemented or a biotin deficient diet consist mainly of triacyglycerols, and of mono- and diester waxes. Diester waxes from both groups were characterized as fatty acid esters of erythro-2,3-alkanediols. A comparison between fatty acid composition of the two groups, however, revealed the following significant differences. Biotin deficient birds showed a fairly high concentration of very long chain fatty acids (C36-C40) which were completely absent in biotin supplemented birds. Further, almost one-third of the fatty acids of diester waxes in biotin deficient birds were unsaturated while those from biotin supplemented birds were predominantly (96%) saturated.  相似文献   
996.
The bacterial flora was studied in the bronchial, pharyngeal secretions and sputum of 80 children with Cystic Fibrosis (CF) and of 21 children with other chronic lung diseases, treated at the Pediatric Clinic (Respiratory Unit), University of Genoa. Staphylococcus aureus was found in 52% of patients, Pseudomonas aeruginosa in 48%, Proteus in 5%. According to the age, the patients have been distinguished into four groups; in the 6-10 and 11-15 year-old group Staphylococcus aureus was the commonest pathogen isolated, while Pseudomonas aeruginosa was found much more commonly in the 16-20 year-old group. Details are given of antibiotic-sensitivity for single strains grown. Intensive care programs, based on specific antibiotic-sensitivity, for in-patients and out-patients, are reported: positive results in treatment courses with Gentamicin, Cephalosporins and Tobramycin are presented.  相似文献   
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999.
Integrated serum concentrations of luteinizing hormone have been compared among 30-minute collections from 10 boys (6-18 years old) and 5 girls (5-11 years old). This study suggests that perpubertal as well as pubertal boys have greater mean integrated concentrations of LH during sleep than during waking. One of two pubertal girls had greater concentrations of LH during sleep, while three prepubertal girls did not.  相似文献   
1000.
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