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31.
The redistribution of spin-labeled phospholipid analogs across the plasma membrane of HepG2 cells, either in suspension or grown as monolayers, was investigated. After incorporation into the outer membrane leaflet spin-labeled aminophospholipids phosphatidylserine (PS) and phosphatidylethanolamine (PE) moved rapidly to the inner monolayer, whereas the analog of phosphatidylcholine (PC) disappeared more slowly from the outer leaflet. The fast, inward movement of the aminophospholipids was abolished after adenosine triphosphate (ATP)-depletion of cells, suggesting the presence of an aminophospholipid translocase in the plasma membrane of these cells. Compared with human red blood cells, the activity of the aminophospholipid translocase is two orders of magnitude higher in HepG2 cells. From these data, a transverse phospholipid asymmetry can be inferred with the aminophospholipids mainly concentrated on the inner monolayer and the choline-containing phospholipids on the outer leaflet. The relevance of the enrichment of PC in the outer membrane leaflet for the formation and composition of the bile is discussed. 相似文献
32.
H Shinozuka T Ohmura SL Katyal AI Zedda GM Ledda-Columbano A Columbano 《Canadian Metallurgical Quarterly》1996,23(6):1572-1577
Several proteins from culture supernatants of Streptococcus sobrinus were able to bind avidly to Sephadex G-75. The proteins could be partially eluted from the Sephadex by low-molecular-weight alpha-1,6 glucan or fully eluted by 4 M guanidine hydrochloride. Elution profiles were complex, yielding proteins of 16, 45, 58 to 60, 90, 135, and 145 kDa, showing that the wild-type strain possessed multiple glucan-binding proteins. Two mutants of Streptococcus sobrinus incapable of aggregation by high-molecular-weight alpha-1,6 glucan were isolated. One mutant was spontaneous, from a cell suspension to which glucan had been added, whereas the other was induced by ethyl methanesulfonate. Both mutants were devoid of a 60-kDa protein, as shown by gel electrophoresis of culture supernatants and whole cells. Amino acid analysis showed that the 58- to 60-kDa protein and the 90-kDa protein were distinct, although both were N-terminally blocked. Both mutants retained their ability to adhere to glass in the presence of sucrose and to ferment mannitol and sorbitol. Both mutants retained their glucosytransferase activities, as shown by activity gels. Western blots (immunoblots), employing antibody against a glucan-binding protein of Streptococcus mutans, failed to reveal cross-reactivity with S. sobrinus proteins. The results show that even though S. sobrinus produces several proteins capable of binding alpha-1,6 glucans, the 60-kDa protein is probably the lectin needed for glucan-dependent cellular aggregation. 相似文献
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34.
M Korbonits PJ Trainer JA Little R Edwards PG Kopelman GM Besser F Svec AB Grossman 《Canadian Metallurgical Quarterly》1997,46(6):751-757
Modern liver surgery is based upon deep knowledge of the surgical anatomy of the liver and improvements with ultrasounds imaging techniques have provided multidimensional interpretations of the liver anatomy intraoperatively. The technical advances with real-time scanning combined with the pioneering efforts of the Japanese liver surgeons have permitted the dynamic adaptation of the functional liver anatomy to the real anatomy, thus intimately aiding in segment oriented anatomical resection. Intraoperative ultrasound afford several advantages such as viewing the internal anatomy in direct relationship to the surface landmarks under the probe, enabling higher frequencies resulting in greater image resolution. The utilization of intraoperative ultrasound can modify the tactics involved with resection of both primary and metastatic liver tumours. The routine use of intraoperative ultrasound is strongly advocated since more complex procedures can be performed safely since the surgeon proceeds with complete knowledge of the real liver anatomy when deciding the feasibility and extent of liver resection. 相似文献
35.
An original operation is proposed for localization of the diverticulum in the descending portion of the duodenum which excludes traumas of the pancreas. Clinical observations are described. 相似文献
36.
V Kamath CN Jones JC Yip BB Varasteh AH Cincotta GM Reaven YD Chen 《Canadian Metallurgical Quarterly》1997,20(11):1697-1701
OBJECTIVE: To assess the effect on various aspects of carbohydrate and lipid metabolism of administering a quick-release formulation of bromocriptine (Ergoset) to obese, nondiabetic, hyperinsulinemic women. RESEARCH DESIGN AND METHODS: Hourly concentrations of prolactin, glucose, insulin, free fatty acid (FFA), and triglyceride were measured for 24 h before and after approximately 8 weeks of treatment with Ergoset. In addition, fasting lipid and lipoprotein concentrations and the steady-state plasma glucose (SSPG) concentration in response to a continuous infusion of somatostatin, insulin, and glucose were determined before and after Ergoset administration. RESULTS: Circulating prolactin concentrations were dramatically decreased (P < 0.001) following treatment, associated with a significant fall (P < 0.05) in 24-h-long plasma glucose, FFA, and triglyceride concentrations. Neither circulating plasma insulin concentrations nor the ability of insulin to mediate glucose disposal changed with treatment. Finally, fasting total cholesterol fell (P < 0.05) and the ratio of total to HDL cholesterol decreased (P = 0.06) in association with Ergoset treatment. CONCLUSIONS: The fact that significant metabolic improvement was seen in the obese nondiabetic hyperinsulinemic women studied suggests that Ergoset could be of therapeutic benefit in clinical conditions of hyperglycemia and/or dyslipidemia. 相似文献
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38.
R Pistelli F Forastiere GM Corbo V Dell''Orco G Brancato N Agabiti A Pizzabiocca CA Perucci 《Canadian Metallurgical Quarterly》1993,6(4):517-522
Six men were accidentally exposed to NO2 when they were changing a propeller using a gas burner in the poorly ventilated hold of a ship. All of them were admitted to hospital with shortness of breath and cough. Chest X-ray on admission revealed diffuse, patchy and infiltrative shadows, leading to the diagnosis of pulmonary edema in all five patients. Steroid therapy was effective and followed by a quick recovery in all patients. None developed third phase manifestations characterized pathologically by bronchiolitis obliterans. 相似文献
39.
The authors report a case of pregnancy in a rudimentary horn diagnosed by laparotomy. The location could not be suspected by any clinical sign. This pregnancy stopped at 19 weeks of amenorrhoea. Any attempts of induction of labour failed. Laparotomy was necessary to assess the diagnosis and to allow the resection of the uterine horn. The authors present a review of literature. 相似文献
40.
IA Likhtarev GM Gulko IA Kairo K Henrichs HG Paretzke 《Canadian Metallurgical Quarterly》1994,66(2):137-146
In the context of the radiation exposure of the Ukrainian population resulting from the Chernobyl accident, the quantification of the thyroid doses due to iodine incorporation is of special interest. This first part of a series of planned publications deals with the dose and risk estimation for Kiev citizens. Although these doses are expected to be considerably lower than those for some other regions of Ukraine, the investigations started with this population because the quantification of the thyroid doses due to iodine incorporation is of special interest. This first part of a series of planned publications deals with the dose and risk estimation for Kiev citizens. Although these doses are expected to be considerably lower than those for some other regions of Ukraine, the investigations started with this population because of the availability of rather reliable measurements and because of the size of this population. The methods developed allowed the estimation of individual thyroid doses. The average values of individual thyroid doses for five age groups (birth years 1983-1986, 1979-1982, 1975-1978, 1971-1974, and < 1971) are 104, 62, 19, 18, and 41 mGy, respectively. The collective thyroid doses were estimated as 83 x 10(3) person-Gy for those born before 1971 and as 38 x 10(3) person-Gy for younger inhabitants. The numbers of expected thyroid cancers in the whole Kiev population are 66 and 130, respectively. 相似文献