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991.
The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves.  相似文献   
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Summary Renal failure after heart transplantation (HTx) still remains a serious problem, especially when cyclosporin A is used for immunosuppression in the early postoperative therapy. To preserve good renal function without reducing immunosuppressive cyclosporin A treatment, we administered urodilatin (CDD/ANP-95-126) in a long-term, low-dose infusion in addition to the usual medication after heart transplantation. From November 1990 to June 1991, 51 patients (46 male and 5 female; mean age 48 years) were treated with a 620 ng/kg bw·min infusion for 96 h after HTx. The renal function and hemodynamic parameters of these urodilatin-treated patients were compared in this sequential study with 40 patients (33 male and 7 female; mean age 49 years) who had undergone HTx previously from May to November, 1990, as controls. In this phase IIa study, both groups did not differ significantly with respect to age, sex, indication for HTx, and preoperative renal function. In comparison with controls patients treated with urodilatin had a significantly better renal function: a reduction in the peak plasma creatinine (PC values day 4 : 1.5 ± 0.11 vs. 2.19 ± 0.19 mg/dl; P = 0.002), a lower peak serum urea (SU values day 4 : 109 ± 8 vs. 154.7 ± 8.94 mg/dl ; P = 0.0036), and a lower incidence of hemodialysis (6% vs. 10%) were observed. Adequate diuresis was maintained in spite of the reduction of furosemide by more than 60% (P = 0.005) on each day of urodilatin infusion in comparison with controls. The mean central venous pressure was significantly lower by about 50% (P = 0.02) during the administration of urodilatin in spite of reduced vasodilator medication with nitroglycerin. From this phase IIa study, we may conclude that urodilatin could be an important drug in intensive care treatment. For patients undergoing HTx, this peptide seems to be indicated for the improvement of renal function and cardiovascular status, especially in postoperative therapy using high-dose cyclosporin A treatment.Abbreviations ACE angiotensin converting enzyme - ANP atrial natriuretic polypeptide - ATG antithymocyte globulin - bpm beats per minute - bw body weight - CDD cardiodilatin - CDD/ANP-99-126 circulating form of vasorelaxant cardiac peptide - CHD coronary heart disease - CyA cyclosporin A - DCM dilated cardiomyopathy - GLM general linear model - hANP human atrial natriuretic polypeptide - HTx heart transplantation - NTG nitroglycerine - PC plasma creatinine - SU serum urea - SAS statistical analysing system  相似文献   
995.
The occurrence of pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 29-32 kd insulin-like growth factor binding protein, now termed type 1 or IGF-bp1, has been examined in the human ovary by monoclonal and polyclonal antibody based radioimmunoassay and immunohistological techniques. Follicular fluids aspirated from 51 follicles of 32 women undergoing hyperstimulation involving buserelin or clomiphene-based protocols contained 35.5-276.0 ng/ml (mean 101.0 mg/ml) of immunoreactive IGF-bp1. Mean fluid concentrations were three times the level of IGF-bp1 detected in paired serum samples, available for 21 women. Immunoreactive IGF-bp1 in follicular fluid exhibited similar dose-response curves to purified protein and amniotic fluid and immunoreactive IGF-bp1 coeluted in gel filtration with a peak of [125I]-IGF-1 binding corresponding to the elution profile of purified IGF-bp1. Gel filtration also revealed the presence in follicular fluid of a greater than 100 kd binding protein with a binding capacity equal to IGF-bp1 under the conditions employed. A highly significant correlation (P less than 0.001) was found between follicular fluid progesterone and IGF-bp1 and a correlation of lower significance was found between oestradiol and IGF-bp1 (P less than 0.05). However, only low levels of immunoreactive IGF-bp1 were detected in supernatant media of granulosa cells in culture (range undetectable to 2.3 ng/ml). Employing monoclonal antibody-based immunohistology, immunoreactive IGF-bp1 was consistently associated with luteinized granulosa cells of corpora lutea rather than paraluteal cells and its intensity of reactivity appeared to reflect luteal phase steroid hormone profiles. No consistent reactivity was detected in preovulatory follicles and granulosa cells in culture, although reactivity was associated with primordial oocytes. Immunoreactive IGF-bp1 was detected in six of nine supernatant media of explants of luteal tissue obtained from five corpora lutea, with levels ranging from undetectable to greater than 200 ng/ml. These observations suggest that IGF-bp1 is primarily related to luteinization of the granulosa and the resultant luteal cells, and if produced by the luteal cells, additional exogenous factors are required to induce production by granulosa cells in vitro.  相似文献   
996.
Processing of antigen for recognition by class II-restricted CD4+ T cells occurs within acidic compartments of the antigen-presenting cell. The exact nature of this compartment has yet to be precisely defined, however, but may vary depending upon the cell type studied and the antigen used. The acidic compartments of macrophages are also responsible for the degradation of ingested micro-organisms and play host to others which are adapted to an intracellular existance. To determine whether the phagolysosome (PL) formed in activated macrophages after ingestion of Leishmania parasites is also a site for entry of antigen into the class II presentation pathway, we have used the approach of genetic transformation. Hence, Leishmania were transfected with the genes for the protein antigens ovalbumin (OVA) and β-galactosidase (β-gal) and after infection were able to deliver these antigens specifically into the PL. Delivery of antigen to this site resulted in the ability of infected macrophages to present these antigens to antigen-specific CD4+ T cells. After taking into account the absolute levels of antigen uptake by macrophages, a 4-h processing period for OVA delivered by this or a soluble route led to equivalent levels of T cell activation. Unlike macrophages pulsed with soluble OVA, those with PL-targeted OVA still retained the ability to stimulate T cells after a 24-h processing period. This enhanced lifespan of antigen in macrophages corresponded to the kinetics of degradation of the parasite, suggesting slow release of antigen into the processing pathway. β-gal presentation from the PL was tenfold less efficient under the same conditions. In addition to providing the first information on antigen processing in a protozoan PL, these studies highlight the usefulness of genetically transformed parasites for these types of studies.  相似文献   
997.
Liver mitochondria of inbred W/SSM rats with inherited increased radical formation reveal the following anomalies: inhibition of oxidative phosphorylation, a lowered transmembrane potential, and alterations in protein-lipid interaction. The membrane viscosity and osmotic stability of mitochondria are unaffected. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N o 6, pp. 628–631, June, 1995  相似文献   
998.
The aim of this prospective randomized controlled study wasto determine the possible role of ovulation induction with intrauterineinsemination (IUI) in the treatment of unexplained infertility.A total of 100 patients were randomized to receive ovulationinduction with or without IUI. All patients were treated withlong-course gonadotrophinreleasing hormone analogue (GnRHa),starting in the luteal phase, and exogenous follicle stimulatinghormone (FSH) to induce follicular growth. Ovulation was inducedusing human chorionic gonadotrophin and timed intercourse (TI)was advised 24–48 h later or IUI was effected 36—48h later. Both the cycle fecundities (21.8 and 8.5%) and thecumulative ongoing pregnancy rates after three cycles (42 and20%) were significantly higher (P < 0.03) in the IUI groupthan in the TI group respectively. This is a clear indicationthat ovulation induction with IUI is an effective treatmentmethod for unexplained infertility, but ovulation inductionwith TI has a negligible impact in this large group of patients.  相似文献   
999.
Unilateral obstruction of a duplicate uterus is very rare. The current recommendation for its correction involves transmural incision of the uterine muscle. A method is presented here that was successfully applied in one patient suffering from this anomaly, using sonographically guided hysteroscopy. This method obviated the need for an extensive operation.  相似文献   
1000.
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