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991.
Kilpatrick David C.; Bevan Bridget H.; Liston William A. 《Human reproduction (Oxford, England)》1995,10(9):2501-2505
The distribution of mannan binding protein (MBP) in blood donorsera was determined by enzyme-linked immunosorbent assay toestablish normal concentrations. Abnormally low MBP concentrationswere found in 16% (21 out of 135) of female partners and 14%(15 out of 108) of male partners of couples experiencing recurrentmiscarriage, compared with <5% of obstetrically normal controls(P < 0.005). This relationship was even stronger (9.5 versus1.0%) and more significant (P < 0.002) when only subjectspresumed to be homozygous for the mutant allele responsiblefor MBP deficiency were considered. By immunohistochemistry,MBP could be demonstrated in first trimester placenta. We suggestthat low concentrations of MBP within the feto-placental unitincrease susceptibility to fetal loss, possibly via an infection-inducedplacental cytokine imbalance. 相似文献
992.
男性胆囊结石患者血清性激素和前列腺素改变的探讨 总被引:1,自引:0,他引:1
借助RIA,对28例胆囊结石男性(平均57.5岁)及26名健康中、老年男性(平均63.3岁)进行了血清雌二醇(E_2)、孕酮、睾酮和前列腺素类(PGs)检测,以探索胆石形成机理。结果,1)在胆石男病人中.平均E_2和平均孕酮水平均高,他们的平均睾酮则低下,与健康对照男性相应诸值比较,差异非常显著或显著(P<0.001,0.05,0.05);2)至于平均PGs,胆石男性组者与健康对照男性相比,前者也相当高(23.01pg/ml对16.31pg/ml),只是两组间差异尚无统计学意义。作者等初步设想,胆石男性小,如同胆石女性那般,本症也可能是某种垂体性腺激素分泌紊乱性疾病。 相似文献
993.
Staessen C.; Janssenswillen C.; van Den Abbeel E.; Devroey P.; van Steirteghem A.C. 《Human reproduction (Oxford, England)》1993,8(10):1650-1653
Attempts to increase the probability of a successful pregnancyin in-vitro fertilization (IVF) treatment by increasing thenumber of embryos transferred automatically also increase theprobability of multiple pregnancies and their attendant risks.Even where the number of transferred embryos is limited to amaximum of three as in this and other centres, there is a highincidence of twins and triplets. The question therefore ariseswhether the number of transferred embryos should be furtherlimited to a maximum of two in cases where the prognosis isotherwise good. The only objection to this idea is a possiblelowering of pregnancy rate. The present study set out to investigatethis question. No significant lowering of pregnancy rate wasfound, so that limiting the number of transferred embryos totwo where the prognosis is otherwise good has now become standardpractice in our centre. A good IVF prognosis was defined bythe following criteria: first attempt for IVF, less than 37years old, and good embryo development. From 183 patients fulfillingthese criteria, 80 agreed to the transfer of two embryos (group1) and 103 opted for a triple transfer (group 2). Patient characteristicsand embryology results were similar in the two groups. In group1, 34 patients (42.5%) became pregnant and in group 2, 50 (48.5%).This difference is not significant. Similarly, twin pregnancyrates in both groups were high; eight twin pregnancies (23.5%)in group 1 and 12 (24%) in group 2. For the triplet pregnancyrate of 18% (nine triplet pregnancies) in group 2, there wasobviously no parallel in group 1. After thawing about half ofthe cryopreserved embryos and subsequently replacing them, preliminarycumulative pregnancy rates of 52.5% in group 1 and 53.4% ingroup 2 were obtained. Future results from cryopreservationshould provide relatively better outcomes for group 1 sinceall the patients in this group had at least one embryo frozenand fewer embryos replaced in the fresh cycle. 相似文献
994.
单用全反式维甲酸(RA)诱导治疗急性早幼粒细胞白血病(APL)20例,完全缓解率达90%,诱导天数短(中位数为32d)。治疗过程中未发生DIC,亦无因强烈化疗引起骨髓抑制后造成的感染和出血的危险。该药的副反应轻,患者均能耐受。该组的中位生存期已达630d,可望长期存活。 相似文献
995.
E. Schulte-Frohlinde S. Schmolke W. Reindl G. Schätzle J. Scherf K. F. Kopp M. Classen & V. Schlüter 《Journal of viral hepatitis》1998,5(5):341-344
Patients on maintenance haemodialysis represent a high-risk group for parenterally transmitted viral infections, such as hepatitis B, C and G. In addition to hepatitis G virus (HGV) (GBV-C) RNA, analysed in previous studies, we characterized the seroprevalence rates of antibodies to the putative E2 protein (anti-E2) of HGV in a German cohort of patients on maintenance dialysis ( n = 72) in comparison to healthy blood donors ( n = 100). The presence of anti-E2 and/or HGV RNA as indicators of present or past HGV infection could be demonstrated in 34.7% of patients and in 16% of the blood donors ( P < 0.01). The infection rates with HGV seem to increase only during the first 6 years of haemodialysis. The simultaneous presence of viraemia and anti-E2 was found very rarely in patients and controls. Therefore, the emergence of anti-E2 indicates clearance of HGV viraemia. In conclusion, patients on haemodialysis are at high risk of acquiring HGV infection, but a chronic carrier state with viraemia is rare. The risk of infection is not strictly correlated with the duration of dialysis. 相似文献
996.
Yoshihiro Hanaki Satoru Sugiyama Kazumi Taki Tadayuki Kato Shohachi Suzuki Takayuki Ozawa Prof. M.D. 《Heart and vessels》1988,4(3):149-152
Summary The present study was designed to clarify whether or not a difference between arterial and venous lactate (lactate) levels is useful for evaluation of mitochondrial function in ischemia-reperfused myocardium. In the first experiment, 12 dogs were divided into 2 groups: 10-min occlusion of the left anterior descending coronary artery (LAD) followed by 10-min reperfusion, or 30-min occlusion followed by 40-min reperfusion, were performed. The lactate levels in the femoral artery and the great cardiac vein were measured enzymatically. Lactate was reversed immediately after occlusion. Ten min and 20 min were required for the recovery of lactate in the 10-min-occlusion with 10-min-reperfusion, and 30-min-occlusion with 40-min-reperfusion groups, respectively. In the second experiment, 36 dogs were divided into 6 groups: 10-min occlusion of LAD; 10-min occlusion with 10-min reperfusion; 30-min occlusion; and 30-min occlusion with 10-, 20-, or 40-min reperfusion were performed. Mitochondria from normal and occluded or reperfused areas were prepared, and the respiratory function of the mitochondria was measured polarographically. No significant decreases in the mitochondrial function were observed in the 10-min-occlusion, and 10-min-occlusion with 10-min-reperfusion groups. On the other hand, respiratory function of mitochondria was impaired by 30-min occlusion and was not improved by 10- or 20-min reperfusion. Significant recovery in the mitochondrial function was observed after 40-min reperfusion. That is, differing recovery time courses between lactate and the mitochondrial function were observed. 相似文献
997.
L. Laurian Z. Oberman E. Hoerer E. Graf 《Journal of neural transmission (Vienna, Austria : 1996)》1988,73(3):167-176
Summary In a previous study we observed that calcitonin increases -endorphin, ACTH, and cortisol secretion. We assumed that calcitonin might have a modulatory role on the pituitary function. The present study was initiated to clarify whether this effect is due to a direct pituitary stimulation or to an indirect stimulation through CRF (corticotropin releasing factor).Fourteen healthy subjects, aged 30–60 years were investigated. All the subjects received 100IU Salmon calcitonin Sandoz i.v. at 8a.m. (time 0). Plasma -endorphin, ACTH and cortisol were estimated every 30min from – 30 to 120 min by specific radioimmunoassay. The same parameters were estimated a second time, at the same intervals, when cyproheptadine 8 mg (7 subjects) and 40 mg propranolol (7 subjects) were given per os at – 30 min and calcitonin i.v. at time 0. -endorphin, ACTH and cortisol levels (Mean ±SEM) rose significantly after calcitonin (peak value at 30–90 min) from 5.2 ±0.7 to 15.1±2.6 pmol/l; from 43.0±2.7 to 70.7±4.1 pg/ml and from 10.6±1.5 to 19.6 ±2.1 g/100 ml respectively (p< 0.0001 by analysis of variance and covariance and repeated measures). Propranolol 40 mg (per os) administered at time – 30 did not alter the response of -endorphin, ACTH and cortisol to calcitonin (infused at time 0).Cyproheptadine, the antiserotonergic substance that inhibits the synthesis and release of CRF completely inhibited the stimulatory effect of calcitonin.We conclude that probably calcitonin has a modulatory role on the hypothalamo-pituitary adrenal axis and that it acts at the hypothalamic level probably by stimulating CRF secretion. 相似文献
998.
Ryozo Oishi Yoshinori Itoh Tamotsu Fukuda Yasunori Araki Kiyomi Saeki 《Journal of neural transmission (Vienna, Austria : 1996)》1988,73(1):65-69
Summary The size of the neuronal and non-neuronal histamine pools in the brain of three different strains of rats was measured by assuming that the -fluoromethylhistidine-induced maximal decrement of histamine represents the size of the neuronal pool. Although the total histamine levels in the brain showed a considerable interstrain variation, no significant interstrain difference was observed in the neuronal histamine level. These results suggest that the size of the neuronal histamine pool in the brain is relatively stable, whereas the size of the non-neuronal histamine pool is variable. 相似文献
999.
S. Turkish P. H. Yu A. J. Greenshaw 《Journal of neural transmission (Vienna, Austria : 1996)》1988,74(3):141-148
Summary A behavioural test involving potentiation of the effects of an acute injection of -phenylethylamine (10 mg kg–1 i.p.) was used to assess the time-course of type-B MAO inhibition after administration of (–)deprenyl (5 mg kg–1 i.p.) and of MD 240928 (20 mg kg–1 i.p.) respectively. Potentiation of the effects of -phenylethylamine was observed 1 h after injection of (–)deprenyl or MD 240928. This effect was still evident 120 h after administration of (–)deprenyl but not 24 h after administration of MD 240928. Comparisons of ex vivo estimates of MAO activity yielded a corresponding time-course for the recovery of this enzyme. The extent of MAO inhibition required for potentiation of the effects of -phenylethylamine was inferred from a comparison of the behavioural test results and the ex vivo MAO activity observed after (–)deprenyl administration. These comparisons indicate a significant underestimation of MD 240928-induced MAO inhibition using ex vivo measures. This underestimation is interpreted as evidence fordilution effects in the ex vivo assay of MAO inhibition. The potentiation of effects of -phenylethylamine under the present conditions is proposed as a useful and simple test for effects of reversible type-B MAO inhibitors. 相似文献
1000.
Prospect for enzyme therapy in glycogenosis II variants: a study on cultured muscle cells 总被引:4,自引:0,他引:4
A. T. van der Ploeg P. A. Bolhuis R. A. Wolterman J. W. Visser M. C. B. Loonen H. F. M. Busch A. J. J. Reuser 《Journal of neurology》1988,235(7):392-396
Summary Impairment of skeletal muscle function is the common feature of distinct clinical forms of glycogenosis type II. In the present study, muscle cultures from different patients were used to investigate the cause of clinical heterogeneity and the feasibility of enzyme replacement therapy. The activity of acid -glucosidase appears to be the primary factor in determining the extent of lysosomal glycogen storage in muscle, and thereby the clinical severity of the disease. Neutral -glucosidases do not seem influencial. Correction of the enzymatic defect was achieved in skeletal muscle cultures from patients by administration of a high-uptake form of acid -glucosidase, purified from human urine. The enzyme reaches the lysosomes, including the glycogen storage vacuoles, and the lysosomal glycogen content is reduced to control level. In normal muscle cells 20% of the total cellular glycogen pool is segregated in lysosomal compartments. This percentage is higher than in fibroblasts, which may partly explain why muscles are more prone to store glycogen. The relevance of this study for enzyme therapy is discussed. 相似文献