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991.
992.
Pasture-grazed dairy cows, deer, and sheep were tested for the presence of ammonia-hyperproducing (HAP) bacteria in roll tubes containing a medium in which tryptone and Casamino Acids were the sole nitrogen and energy sources. Colonies able to grow on this medium represented 5.2, 1.3, and 11.6% of the total bacterial counts of dairy cows, deer, and sheep, respectively. A total of 14 morphologically distinct colonies were purified and studied further. Restriction fragment length polymorphisms of 16S rRNA genes indicated that all isolates differed from the previously described HAP bacteria, Clostridium aminophilum, Clostridium sticklandii, and Peptostreptococcus anaerobius. Carbon source utilization experiments showed that five isolates (C2, D1, D4, D5, and S1) were unable to use any, or very few, of the carbon sources tested. Biochemical tests and phylogenetic analyses of 16S ribosomal DNA sequences indicated that all isolates were monensin sensitive; that D1 and S1 belonged to the genus Peptostreptococcus, that D4 and D5 belonged to the family Bacteroidaceae, where D4 was similar to Fusobacterium necrophorum; and that C2 was most similar to an unidentified species from the genus Eubacterium. Growth on liquid medium containing tryptone and Casamino Acids as the sole nitrogen and energy source showed that D1, D4, and S1 grew rapidly (specific growth rates of 0.40, 0.35, and 0.29 h-1, respectively), while C2 and D5 were slow growers (0.25 and 0.10 h-1, respectively). Ammonia production rates were highest in D1 and D4, which produced 945.5 and 748.3 nmol/min per mg of protein, respectively. Tests of individual nitrogen sources indicated that D1 and D4 grew best on tryptone, S1 grew equally well on Casamino Acids or tryptone, and C2 and D5 grew poorly on all nitrogen sources. The intact proteins casein and gelatin did not support significant growth of any of the isolates. These isolates extend the diversity of known HAP rumen bacteria and indicate the presence of significant HAP bacterial populations in pasture-grazed New Zealand ruminants. 相似文献
993.
AV Ivanitski? BG Alekian VA Kriukov AV Sobolev BM Shukurov MG Pursanov 《Canadian Metallurgical Quarterly》1996,(5):26-34
The paper analyzes the first experience with intravascular ultrasound study (IUSS) in 9 patients at the Cardiosurgery Center. It presents the potentialities of IUSS during interventional radiological procedures. It is concluded that there are benefits and trends of the technique in the exploration of various vascular beds. 相似文献
994.
Naive T lymphocytes have the potential to differentiate and produce a range of cytokines crucial for appropriate immune responses. How T lymphocytes vary their cytokine output during differentiation is unknown, although they are clearly influenced by the cytokines already present in the environment. Here we show that the number of divisions taken by the cells after activation is a critical element in T cell differentiation. Our experiments used the dye 5-(and 6-)carboxyfluorescein diacetate, succinimidyl ester to track cells in different divisions after activation by anti-CD3 in the presence of the differentiating cytokine interleukin (IL)-4. The patterns of acquisition or loss of secretion of IL-2, IL-3, IL-4, IL-5, IL-10, and interferon gamma all varied markedly with division number. These relationships were consistent regardless of the time-dependent variation in distribution of T cells among divisions. Thus, the observed combination of complex asynchronous T cell growth, overlaying a fixed probability of acquisition or loss of a cytokine at each division can explain why T cell differentiation displays the contradictory features of being both highly stochastic and highly controlled. Furthermore, these data reveal that T cells share a common regulatory strategy with B cells, whereby changes in the class of immune response are linked to the process of clonal expansion. 相似文献
995.
NI Karpov AA Baranov EL Nasonov AV Zakutskii NP Shilkina II Barteneva OP Rechkina 《Canadian Metallurgical Quarterly》1996,74(4):42-45
Antibodies to cardiolipin (ACL) were detected in 12 (35%) of 34 patients with tumors of the ovaries. 8 of 12 patients exhibited clinical signs of antiphospholipid syndrome, 9 (75%), 2 and 1 patients demonstrated isolated hyperproduction of IgG ACL, combined rise of IgG ACL and IgM ACL, IgM ACL, respectively. Most frequently ACL occurred in endometriosis of the ovaries and serous cystadenomas (50 and 60%, respectively). In 5 (42%) of 12 patients CA-125 antigen concentration was above the upper norm (35 U/ml), in 3 (25%) cases the level of CA 19-9 antigen was elevated. There were parallel changes of ACL concentration and tumor marker CA-125 before and after operation. Autoimmune origin of ovarian endometriosis is suggested. 相似文献
996.
SI Emeljanov VV Fedenko EM Levite SA Panfilov IG Bobrinskaya AV Fedorov NL Matveev VV Evdoshenko SV Luosev VV Bokarev SR Musaeva 《Canadian Metallurgical Quarterly》1998,12(10):1224-1231
BACKGROUND: This study was initiated to find a method of determining the prognosis for possible changes in hemodynamic and respiratory parameters in patients with pneumoperitoneum (PP). METHODS: We devised a model for a pseudopneumoperitoneum (PPP), which is created by encircling the wide pneumochamber on the entire abdomen and inflating it to a preset pressure. To verify the prognostic possibilities of the proposed model, we studied the pneumotachygraphy parameters, noninvasive and invasive monitoring parameters of PPP after induction of anaesthesia, and venous circulation disturbances, as well as the medical effect of the intermittent sequential compression device. RESULTS: In healthy patients, the restrictive lung syndrome did not approach the risky limit. In patients >/=60 years old, this syndrome was very close to the limit. In a number of patients with serious cardiovascular and pulmonary pathology, the pressure of >10 mmHg was considered to be intolerable. Lung compliance, which was the parameter most sensitive to the increased intraabdominal pressure, was 47 +/- 10 at baseline, and 29 +/- 4 (p > 0.05) at both PPP and real PP (14 mmHg). CONCLUSIONS: The PPP model is quite similar to the real PP and can be used for preoperative prognosis in laparoscopic surgery. The elevated intraabdominal pressure results in a significant disturbance of venous blood flow in the lower extremities. The use of the device for peristaltic pneumomassage of the lower limbs is effective in correcting negative changes in venous hemodynamics in laparoscopic surgery. 相似文献
997.
KM Abdulkadyrov LV Stel''mashenko SS Bessmel''tsev IF Lubo-Lesnichenko AV Sel''tser OE Rozanova NK Gubarenko LN Bubnova MM Mnuskina AA Zhuchikhina MN Blinov NL Gritskevich 《Canadian Metallurgical Quarterly》1998,44(3):304-309
The aim of this study was to measure serum carbohydrate-deficient transferrin (CDT) in consecutive patients attending a general medical clinic with a range of alcohol intakes to determine its value in assessing such intake. Eighty-one consecutive patients (42 male, 39 female) aged 20-85 years (median = 49.5 years) attending an out-patient clinic were selected for the study. Each patient completed an alcohol diary detailing the units of alcohol consumed in the previous week, a CAGE questionnaire and an alcohol history, and underwent conventional blood tests including mean corpuscular volume (MCV), liver function tests, and gamma-glutamyl transferase (GGT). CDT was estimated using an enzyme immunoassay (CDTect, Pharmacia). The group comprised of 17 teetotallers, 28 light (<100 g/week), 23 moderate (100-400 g/week), and 13 heavy (>400 g/week) drinkers. Median serum CDT for heavy drinkers (25.5 U/l) was significantly higher than for the rest (median = 17 U/l, Kruskal-Wallis test, P = 0.01). Serum CDT correlated significantly with the CAGE score (Mann-Whitney test, P = 0.01), but poorly with alcohol diary records (r = 0.1, P = 0.4). However the correlations between GGT and diary records (r = 0.43, P = 0.001) and MCV with diary records (r = 0.5, P < 0.001) were significant. Sensitivity, specificity, and positive predictive value for elevated serum CDT were 69, 81 and 41% respectively in detecting heavy drinking. The positive predictive values for the various parameters were 43% for elevated serum GGT, 41% for raised erythrocyte MCV, and 75% for a positive score on the CAGE questionnaire. When a combination of the markers CDT, GGT, and MCV was used, elevation in two of the three markers detected heavy drinking with sensitivity of 85%, specificity of 88%, and positive predictive value of 61%. We conclude that, in out-patients with a wide range of alcohol intakes conventional markers such as serum GGT and erythrocyte MCV were more suitable than serum CDT for assessing alcohol intake. Serum CDT when used in combination with serum GGT and erythrocyte MCV was useful in detecting heavy drinking. The importance of careful history-taking including a standardized questionnaire is emphasized. 相似文献
998.
Analytical review of the morphological investigations of cerebral cortex neurons of various animals shortly after exposure to X- and gamma-radiation was made. Considered were data of qualitative and quantitative analyses of dystrophic changes in neurons of the sensorimotor cortex of the large cerebral hemispheres of rats immediately and a long period since X-irradiation. Results of the quantitative analysis of structural disorders in the central nervous system neurons suggest radiation-produced damages early after exposure of animals to relatively low doses. Higher incidence of irreversible changes in neurons of the experimental animals, as compared with intact controls, was stimulated by the doses of no more than 0.25 to 1.0 Gy. The relative number of structural disorders in neurons and percentage of irreversibly impaired cells rose proportionally to the dose growth and further delay of the time of investigation. Possible mechanisms of delayed disorders that led to a massive building-up of the number of dystrophic neurons following 3 to 4 months post irradiation of rats are discussed. 相似文献
999.
1000.