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21.
Summary Five monoclonal antibodies against the excretory/secretory (E/S) antigen of Toxocara canis were obtained and characterized. Immunoprecipitating activity was demonstrated in an in-vitro micropre-cipitating assay using live T. canis larvae. Their capacity to kill larvae was also shown in an in-vitro assay. Two zones of reactivity were observed in 7.5 and 12.5% SDS-PAGE (177-77 kD, 43-15 kD) of immunoprecipitates of human and mouse positive polyclonal anlisera. The murine monoclonal antibodies showed a common pattern of reactivity with the proteins in the 177-77 kD range.  相似文献   
22.
The effects of daily oral administration of a high dose of 10 mg norethisterone acetate (NET-Ac.)/kg/day over 14 weeks on serum lipid and lipoprotein parameters as well as on blood coagulation were investigated in female monkeys (M. fascicularis). Measurements of lipids and lipoprotein cholesterol were performed in weeks —5 and — 1 before treatment and in weeks 4, 8 and 12 after treatment. In addition, various blood coagulation and fibrinolytic parameters were determined in weeks 11–14 after treatment with NET-Ac. Furthermore, the serum levels of norethisterone (NET) were determined in order to monitor the real systemic compound exposure and revealed that Cmax and AUC (0–3 h) values reached for norethisterone in this experiment in monkeys were about 25 times higher than those obtained after an oral contraceptive dose of NET-Ac. in women.

The results of lipid and lipoprotein cholesterol determinations showed decreases in serum total lipids, phospholipids, triglycerides and total cholesterol associated with similar decreases in HDL-, LDL- and VLDL-cholesterol fractions after NET-Ac.-treatment in monkeys. These effects were observed from week 4 onwards and maintained their magnitude up to week 12 after treatment. Since both HDL- and LDL-cholesterol fractions decreased, the HDL/LDL-ratio remained almost unchanged. Thus, the results obtained in this study after high-dose treatment with NET-Ac. in monkeys did not indicate any changes of lipid and lipoprotein parameters which in humans are supposed to be associated with an increased risk of cardiovascular lesions, namely a decrease in HDL- and increase in LDL-cholesterol fractions.

The results of blood coagulation and fibrinolytic parameters showed increased antithrombin-III and plasminogen levels besides minor changes in other parameters, thus indicating that NET-Ac. -treatment does not contribute to an increased risk of cardiovascular thrombotic events in the cynomolgus monkey.  相似文献   

23.
Abstract: The dependence of transient pressure characteristics of a ventricular assist device (VAD) on the compliance of its housing and cannulas was investigated in a mock circulation. The peak rate of change of pressure ( dP/dt max) values was greater in the cannulas than other compartments and was associated with valve closure-induced pressure oscillations. When cannula compliance was increased from 0.0057 to 0.0129 cm3/mm Hg, these values decreased by ˜20%, and outflow cannula pressure oscillation frequency decreased from 17.5 Hz by 35%. This trend was also apparent in the inflow. A VAD housing compliance increase from 0.0162 to 0.0483 cm3/mm Hg caused a dP/dt max decrease of 30% in both the blood chamber and the outflow cannula. The effect of this change on the inflow was weaker implying that housing absorbs the energy associated with outflow deceleration more effectively than the inflow. These findings suggest that increasing VAD housing and cannulas compliance can improve hydrodynamic performance.  相似文献   
24.
This study examined the feasibility of isolating and transferringthe centrosome-containing region of spermatozoa to mature humanoocytes. The findings demonstrate that individual sperm centrosomescan be transferred and are capable of nucleating maternal tubulinto form a well-developed sperm aster in the recipient oocyte.The results are discussed with respect to centrosome functionin early human development and applications in clinical in-vitrofertilization in the treatment of certain forms of male factorinfertility.  相似文献   
25.
Zusammenfassung Zahlen zur H?ufigkeit von Herztumoren im operativen Krankengut liegen bisher für die Bundesrepublik Deutschland nicht vor. Um einen entsprechenden überblick für das Jahr 1996 zu erhalten, wurde allen 77 herzchirurgischen Zentren der Bundesrepublik Deutschland ein standardisierter Fragebogen zugesandt. Daten von 65 der 77 Herzzentren (=84%) waren schlie?lich verfügbar: 187 Patienten waren wegen Myxomen, lediglich 44 wegen nichtmyxomat?sen Tumoren, davon 28 wegen malignen prim?ren oder sekund?ren Herztumoren, operiert worden. Im Jahr 1996 waren somit 0,32% (231/72 763) der Eingriffe mit Herz-Lungen-Maschine (erfa?t 72 763 von insgesamt 87 372) wegen eines Herztumors vorgenommen worden. Ausgehend von diesen operativen Daten liegt die Inzidenz ausschlie?lich der prim?ren Tumoren des Herzens zumindest bei 3 Tumoren pro 1 Million Einwohner pro Jahr (253 Tumoren/81,814 Millionen Einwohner). Wenn auch kleine Tumoren asymptomatisch und unentdeckt bleiben k?nnen, wird heute doch die Mehrzahl prim?rer kardialer Tumoren durch Echokardiographie, Computer- und Kernspintomographie bereits zu Lebzeiten des Patienten diagnostiziert, und diese Patienten werden in aller Regel einer Operation zugeführt. Somit werden gut 0,3% aller Eingriffe mit Herz-Lungen-Maschine in Deutschland wegen Herztumoren durchgeführt, wobei es sich weit überwiegend um Myxome handelt. Eingegangen: 23. September 1997, Akzeptiert: 11. Februar 1998  相似文献   
26.
对13例体外循环病人进行了观察,发现体外循环后TXB2/6-keto-PGF1α显著增高,表明体外循环使血小板受损,而血小板受损是体外循环后失血的主要原因之一。  相似文献   
27.
28.
本研究选择10μg/ml、20μg/ml、40μg/ml浓度的溴氰菊酯处理白纹伊蚊C6/36细胞,以MMC作为阳性对照物,观察溴氰菊酯处理24h后对C6/36细胞染色体畸变率和姐妹染色单体互换(SCE)频率的影响。结果显示,三个浓度的溴氰菊酯对C6/36细胞染色体畸变率均没有显著影响(P<0.05);溴氰菊酯浓度在40μg/ml时可诱导C6/36细胞SCE频率轻度增高(P>0.05),而溴氰菊酯浓度在10μg/ml、20μg/ml时,对C6/36细胞SCE频率没有诱导作用。表明溴氰菊酯对C6/36细胞的遗传学效应较弱  相似文献   
29.
Image-directed color Doppler ultrasonography (ICDUS) studies of 86 patients with superficial solid masses yielded significantly lower resistive index (RI) values in acute inflammatory lesions, but no significant difference between the maximum systolic flow velocities (S) of the patient groups with malignant, benign, and acute inflammatory lesions. When analyzed separately, the malignant soft-tissue tumor subgroup was shown to have significantly higher mean RI compared to that of the malignant node subgroup. We conclude that RI may be useful in the differentiation of acute inflammatory masses from other pathological entities. Malignant soft-tissue tumors, especially sarcomas, may have different Doppler features from those of carcinomatous tumors. © 1995 John Wiley & Sons, Inc.  相似文献   
30.
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