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961.
962.
In experiments on white male mice there was studied the influence of piracetam (250-300 mg/kg) on the analgesic effect of ligands of different types of opioid receptors (morphine, 7.5 mg/kg, DADLE, 7.5 mg/kg, pentazocine, 15 mg/kg) and also on the action of morphine concerning the cardiovascular system and respiration. Piracetam was shown to possess the antagonistic properties with respect to some effects of morphine, however they are not of the universal character and do not depend on the interaction with a certain type of opioid receptors.  相似文献   
963.
964.
Under examination there were 198 patients with severe mechanical traumas at their admission to the clinic and on the 1st, 3d, 7th, 14th and 21st days by 25 hemocoagulation parameters determined by common present-day methods. The direction and degree of hemocoagulation alterations were found to be related with the severity of trauma, blood loss volume and severity of shock. It was shown that disseminated intravascular coagulation (DIC) of the II and III degree was developing in critical associated traumas, massive blood loss and severe shock in acute period of the disease. The acute form of DIC with reactive fibrinolysis was established in the lethal outcome during the shock period, latent (slow) DIC with local fibrinolysis took place in lethal outcomes in later periods.  相似文献   
965.
Two cohort studies showed an association between moderate alcohol consumption and breast cancer, with an apparent relative risk of 1.50. Drinkers and nondrinkers already differed in important ways at the initiation of these two studies, precluding a causal interpretation of the associations found. Women in need of the relaxing effect of alcohol may indeed be the group at higher risk for breast cancer. Inasmuch as the studies did not inquire into other cancers, morbidities, mortalities, or total mortality, they leave open the possibility that, on balance, moderate alcohol consumption is beneficial.  相似文献   
966.
BACKGROUND: Enhanced expression of the suppressor of cytokine signalling (SOCS)-5 might be of therapeutic benefit for T-helper type 2 (Th2) dominant diseases, as its expression is reported to result in a reduction of Th2 differentiation in vitro due to the inhibition of IL-4 signalling. OBJECTIVE: To investigate the regulatory role of SOCS-5 in vivo, we explored the phenotype of an experimental asthma model developed in SOCS-5 transgenic (Tg) mice. METHODS: The SOCS-5 Tg mice or wild-type (WT) mice were sensitized and repeatedly challenged with ovalbumin (OVA). We examined bronchoalveolar lavage fluid (BALF), lung specimens, and airway hyperresponsiveness (AHR) to methacholine. RESULTS: The production of IFN-gamma by CD4(+) T cells from unprimed SOCS-5 Tg mice was significantly increased in comparison with unprimed wild-type mice, indicating that SOCS-5 Tg mice have a Th1-polarizing condition under natural conditions. However, in an asthma model, significantly more eosinophils in the airways and higher levels of IL-5 and IL-13 in BALF were observed in the SOCS-5 Tg than the wild-type mice. AHR in the asthma model of SOCS-5 Tg was also more enhanced than that of wild-type mice. OVA-stimulated CD4(+) T cells from the primed SOCS-5 Tg mice produced significantly more IL-5 and IL-13 than CD4(+) T cells from wild-type mice. CONCLUSION: Our results demonstrate that the overexpression of SOCS-5 does not inhibit Th2 response, but rather augments the phenotype of the asthma model in vivo. This finding throws into question the therapeutic utility of using enhancement of SOCS-5 expression for Th2-dominant disease.  相似文献   
967.
The isolated fourth ventricle (IFV) develops in which obstruction to the out flow of cerebrospinal fluid from the choroid plexus of the fourth ventricle occurs rostrally and caudally. IFV has been a rare occurrence and is difficult to treat. We had an occasion to admit a 28-year-old female to our hospital due to hydrocephalus: she also had a history of meningitis a year ago. The patient was initially managed by a lateral ventriculo-peritoneal shunting procedure. Six months after the procedure the patient began to suffer from vomiting, nausea, and diplopia. CT and MRI scans demonstrated an isolated fourth ventricle enlargement; and thus, a fourth ventriculo-peritoneal shunting procedure was performed under stereotactic conditions. The authors present a case of an isolated fourth ventricle after lateral ventriculo-peritoneal shunting for hydrocephalus, which was treated with a stereotactically guided fourth ventriculo-peritoneal shunting procedure. The technique of this procedure is described below.  相似文献   
968.
The authors describe 21 cases with resection of the retinal rupture valve with Nd:YAG laser impulse, performed to reduce the vitreoretinal tractions. Resection of the 'dump' rupture valve has been carried out in 10 cases, in the rest 11 the operation has been performed in the presence of a detachment of the retina. Anatomic success (detachment of the valve from the retina) has been achieved in 16 cases. The technique of the surgery is described, as are indications and contraindications to the operation.  相似文献   
969.
970.
Abnormal pressor responses are known to occur in the maternal circulation in pregnancy-induced hypertension (PIH), but little is know of the response of the foetal circulation. The responsiveness of umbilical arteries in PIH can be studied after delivery, and this is a useful model to explore the pathophysiological mechanisms involved. In the present experiments, the in vitro response of umbilical artery rings to bradykinin and 5-hydroxytryptamine (5-HT) was tested and ultrastructural changes investigated. Umbilical arteries from 48 cords were studied. Fifteen of the mothers had PIH, five had essential hypertension pre-dating the pregnancy and five had diabetes. Twenty-three women had pregnancies uncomplicated by hypertension or serious medical or obstetric problems and these served as controls. Umbilical arteries from the severe proteinuric PIH group were significantly more responsive to 5-HT as assessed by affinity constants (P less than 0.05). The responsiveness of arteries from all other groups did not differ from the normal cases. A probable mechanism for the findings is endothelial damage as a result of pre-eclamptic disease. This was substantiated by ultrastructural evidence.  相似文献   
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