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991.
Polyclonal rabbit antibodies specific to a species-specific M. bovis antigen were used to isolate a species-specific antigen from the PPD. The preparation obtained was active and possessed a higher specificity than the PPD in skin reactions in sensitized guinea pigs.  相似文献   
992.
Studies of local immunity in breast cancer patients were performed in relation to its dependence on tumor levels of estrogen receptors. They demonstrated that progression of breast cancer depends much on the presence of estrogen receptors which occur in 33% of premenopausal and in 68.3% of postmenopausal women; local humoral immunity depends on hormonal presentation of the tumor. When the latter contains estrogen receptors, synthesis of IgSA (stage I-IIa) and of IgSA, A, IgG, IgM (stage IIb-IIIb) appears inhibited; less affected is local immunity with negative estrogen receptors in the tumor as evidenced by the reduction or absence of IgSA in a half (stage I-IIa) or all cases (stage IIb-IIIb) in unchanged levels of the other immunoglobulins.  相似文献   
993.
We report on a sister and brother with severe mental retardation, bulbous tip of the nose, long columella, cleft lip and palate, heart and intestinal anomalies, and growth retardation. This appears to be a previously unreported, autosomal recessive condition, given high resolution prometaphase chromosomes are normal.  相似文献   
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996.
Toxoplasma encephalitis is the commonest cause of intracranial mass lesions in AIDS patients. Effective therapy includes pyrimethamine plus sulfadiazine, clindamycin with pyrimethamine, and co-trimoxazole. This study examines the efficacy of oral co-trimoxazole in 20 AIDS patients with toxoplasmosis and seeks to confirm the experience of Torre et al.  相似文献   
997.
Activation of mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels protects the brain against ischemic or chemical challenge. Unfortunately, the prototype mitoK(ATP) channel opener, diazoxide, has mitoK(ATP) channel-independent actions. We examined the effects of BMS-191095, a novel selective mitoK(ATP) channel opener, on transient ischemia induced by middle cerebral artery occlusion (MCAO) in rats. Male Wister rats were subjected to 90 mins of MCAO. BMS-191095 (25 microg; estimated brain concentration of 40 micromol/L) or vehicle was infused intraventricularly before the onset of ischemia. In addition, the effects of BMS-191095 on plasma and mitochondrial membrane potentials and reactive oxygen species (ROS) production in cultured neurons were examined. Finally, we determined the effects of BMS-191095 on cerebral blood flow (CBF) and potassium currents in cerebrovascular myocytes. Treatment with BMS-191095 24 h before the onset of ischemia reduced total infarct volume by 32% and cortical infarct volume by 38%. However, BMS-191095 administered 30 or 60 mins before MCAO had no effect. The protective effects of BMS-191095 were prevented by co-treatment with 5-hydroxydecanoate (5-HD), a mitoK(ATP) channel antagonist. In cultured neurons, BMS-191095 (40 micromol/L) depolarized the mitochondria without affecting ROS levels, and this effect was inhibited by 5-HD. BMS-191095, similar to the vehicle, caused an unexplained but modest reduction in the CBF. Importantly, BMS-191095 did not affect either the potassium currents in cerebrovascular myocytes or the plasma membrane potential of neurons. Thus, BMS-191095 afforded protection against cerebral ischemia by delayed preconditioning via selective opening of mitoK(ATP) channels and without ROS generation.  相似文献   
998.
In the random sample of 762 males aged 30-59 years who had moved to Chukotka, the attitude towards their health, a physician, bad habits, and prevention of diseases was examined within the Programme on Epidemiology of Major Non-Communicable Diseases and Their Risk Factors among the residents of the Chukotsky Autonomous District. The non-aboriginal Chukotka's population having higher risk factors showed decreased self-appraisal of their health, inadequate awareness of their health and risk factors for diseases. However, the majority of the male population consider it useful to be surveyed, which should be borne in mind in implementing educational measures among these population groups.  相似文献   
999.
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Introduction Myxopapillary ependymomas are low grade tumours that are known to recur locally even after complete excision, but metastasis to distant sites is extremely uncommon. Case report We report an unusual case of lumbo-sacral myxopapillary ependymoma in a 13-year-old boy with metastasis to both cerebellopontine angles. To the best of our knowledge, this is the youngest patient of metastatic myxopapillary ependymoma.  相似文献   
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