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961.
Epitestosterone, a C19-steroid with anti-androgenic activity, was determined in the plasma of 234 boys and men from the ages of 6-86 years, and in the prostate tissue of 15 men 55-82 years of age. It was documented that, while in adulthood the concentration of epitestosterone is about ten times lower than the concentration of testosterone, in the pre-pubertal period the level of epitestosterone is similar or even higher than that of testosterone. In the hyperplastic prostate tissue the content of epitestosterone is comparable to that of androstenedione, it is about twice as high as the content of testosterone and approximately half that of the content of dihydrotestosterone. At least in the case of pre-pubertal boys and in the prostatic tissue it is therefore possible to include epitestosterone into consideration as a regulatory factor for the androgen-dependent events. 相似文献
962.
Vascular endothelium is involved in the control of thrombosis by influencing among other things, platelet functions, coagulation and fibrinolysis. Fibrinolysis is due to plasminogen conversion into plasmin by activators, which are efficiently and rapidly controlled by a specific inhibitor. Endothelium plays a pivotal role in these associations. It is a constitutive and inducible source of activators and inhibitor. It provides a favorable microenvironment for plasmin generation at the vessel surface. Furthermore, the fibrinolytic system participating in angiogenesis is implicated in plaque survival. Subjected to a pathological environment, endothelial activation leads to change in endothelial properties especially by increasing the production of inhibitor of plasminogen activators. These modifications could combine to create locally or distantly, a state predisposing to thrombosis. 相似文献
963.
We report confirmation of the site of leakage in two patients with spontaneous cerebrospinal fluid (CSF) rhinorrhoea by demonstrating CSF leaking on MRI. Both patients had midline anterior cranial fossa floor (cribriform plate/fovea ethmoidalis) dural-bone defects with arachnoid herniation with or without brain herniation into the upper part of the nasal cavity on MRI, which was subsequently confirmed surgically. Corresponding to the history of postural induction or aggravation of the rhinorrhoea, the CSF leak was demonstrated by the appearance of or increase in the sinonasal fluid collection by imaging the patient in the position of maximum leakage following initial images in the supine position. 相似文献
964.
A collagen peptide motif (DGEA) which is a putative alpha 2 beta 1 integrin binding site was examined for its ability to activate Ca2+ signalling pathways in the human osteoblast-like cell line SaOS-2. We show that these cells express both alpha 2 beta 1 integrin subunits (by immunocytochemistry) and that an anti-beta 1 monoclonal antibody (DF5) mobilizes Ca2+ in these cells. DGEA elevated intracellular Ca2+ in fura-2-loaded cells, in a concentration- and sequence-dependent fashion, with an EC50 of 250 microM. The tyrosine kinase inhibitor herbimycin A reduced the number of cells responding to DGEA and to transforming growth factor alpha. Thrombin also stimulated a rise in intracellular Ca2+, but the number of cells responding was not reduced by herbimycin A. The DGEA response was dependent on extracellular Ca2+, but was not due to Ca2+ influx, since it was blocked by thapsigargin and not by lanthanum. Using three different anti-alpha 2 monoclonal antibodies, we were unable to show that the DGEA-induced Ca2+ signal was mediated by the alpha 2 beta 1 integrin. In summary, the DGEA collagen motif does appear to activate receptor-mediated Ca2+ signalling events in SaOS-2 cells, in a divalent cation-dependent manner, but we were unable to demonstrate a role for alpha 2 beta 1 integrin in this response. 相似文献
965.
966.
MS Kramer AL Coates MC Michoud S Dagenais D Moshonas GM Davis EF Hamilton B Nuwayhid AK Joshi A Papageorgiou 《Canadian Metallurgical Quarterly》1995,142(10):1078-1088
Previous studies suggest that women with asthma are at increased risk of preterm birth. Moreover, drugs (especially beta-agonists) used to treat asthma are also used to treat preterm labor. The authors carried out a case-control study of 555 women from three hospital centers with idiopathic preterm labor (< 37 weeks), including two overlapping (i.e., non-mutually exclusive) subsamples: cases with early idiopathic preterm labor (< 34 weeks) and cases with idiopathic recurrent preterm labor (< 37 weeks plus a previous history of preterm delivery or second-trimester miscarriage). Controls were matched to cases according to race and smoking history prior to and during pregnancy. All subjects responded in person to questions about atopic, respiratory, obstetric, and sociodemographic histories. Subjects in the early and recurrent preterm labor subsamples were also asked to undergo spirometric testing with methacholine challenge 6-12 weeks after delivery. Cases were significantly more likely to report histories of asthma symptoms and physician-diagnosed asthma (matched odds ratios of 2-3) than controls, particularly those cases with recurrent preterm labor. No significant associations were observed, however, with methacholine responsiveness. These results could not be explained by residual confounding by smoking or other variables, nor by selective recall of asthma symptoms and histories by cases. Women with asthma are at increased risk of idiopathic preterm labor. The fact that no such association was seen with methacholine responsiveness suggests that nonatopic, noncholinergic mechanisms may link bronchial and uterine smooth muscle lability. 相似文献
967.
RL Troop GM Losse JG Lane DB Robertson PS Hastings ME Howard 《Canadian Metallurgical Quarterly》1995,16(11):705-709
The purpose of this study was to evaluate the clinical outcome of patients treated with limited immobilization and early motion after repair of acute Achilles tendon ruptures. Thirteen consecutive patients with complete ruptures of the Achilles tendon were identified, repaired, and rehabilitated with early motion starting an average of 10 days after surgery. Active range of motion was begun at an average of 23 days and weightbearing in a walking boot was started at an average of 3.5 weeks after surgery. The average length of follow-up was 27 months. Twelve of 13 patients returned to running activities in an average of 3 months. All 12 patients who participated in lateral motion activities before their injury returned to similar activities in an average of 7 months. The patients rated their overall status at an average of 93% of their preinjury level. Follow-up Cybex testing demonstrated plantarflexion strength averaging 92%, plantarflexion power averaging 88%, and plantarflexion endurance averaging 88% of the nonindexed extremity. Early range of motion after Achilles repair is safe and there is no increased risk of rerupture in compliant patients. The patients achieved good return of plantarflexion strength, power, and endurance. 相似文献
968.
Blatant examples of breeches of confidentiality are less common in comparison to the daily indiscretions that occur by members of the health care team or support staff. Yet such breeches of confidentiality are rarely identified as ethical or legal problems and therefore remain unaddressed. To uphold their moral and legal obligation to protect private information, nurses must examine the nature of their obligations and devise strategies to create and maintain a culture that holds health care professionals accountable for their actions. 相似文献
969.
970.