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31.
AIM: The study of the detection rate and potential pathogenetic significance of antibodies to low density oxidated lipoprotein (LDOL) in patients who had ischemic cerebral circulation disorder (ICCD) at young age. MATERIALS AND METHODS: The examination (enzyme immunoassay, general and neurological investigations, laboratory and instrumental tests) covered 148 patients who survived ICCD at young age (mean age 37.2 years). RESULTS: 48 of 108 (44%) patients had LDOL antibodies. Antibodies to cardiolipin, lupus anticoagulant were recorded in 33 (31%) patients. LDOL antibodies were higher and occurred more frequently in patients with Sneddon's syndrome (35% of patients, mean LDOL antibodies-44 units) and primary antiphospholipid syndrome (17% of patients, 45 units) than in atherosclerotic affection of the major head arteries (4%, 29 units) or occlusion of cerebral arteries of unclear genesis (8% of patients, 29 units). CONCLUSION: ICCD were not related to fast development of cerebral atherosclerosis or periaortitis due to production of LDOL antibodies as no relationships were found between their rise and atherosclerotic lesions of cerebral major arteries or periaortitis as shown by ultrasonic dopplerography or cerebral angiography. Feasibility of LDOL antibodies participation in the coagulation cascade and induction of hypercoagulatory condition causing ICCD needs special investigation.  相似文献   
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The study included 138 patients operated on for endo-extracellular pituitary adenomas which extend both intracranially and into the structures of the base of the skull. Operations via transcranial and transsphenoidal access to various tumor sites were performed in 38 patients (a main group), while 100 patients (a control group) underwent one of these operations. Two-stage operations, followed by removal of the suprasellar and basal regions of a tumor, are expedient for enhancing the efficiency of surgical treatment, reducing the incidence of complications associated with traumatic attempts at removing tumor parts hard-to-reach by transcranial or transsphenoidal approaches, as well as at reducing the number of relapses. At the first stage of surgical treatment it is advisable to make an intervention via transcranial access especially in cases of complex configuration of the suprasellar part of a tumor. The recommended interval between transcranial and transsphenoidal surgeries is 3-5 months. Two-stage surgical treatment does not lead to significant structural changes and to the increased number of complications, and to higher mortality rates as compared to one-stage surgery (transcranial or transsphenoidal surgeries alone).  相似文献   
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Blood biochemical parameters of lipid, protein, carbohydrate and energy metabolism were measured in a 135-day chamber experiment. Also, dynamics of the intensity of lipid peroxidation and status of the antioxidant defence system were evaluated. Results of the investigation showed that extended chamber isolation led to modifications of several biochemical parameters including hemoglobin, bilirubin, cholesterol and its fractions, elevated transaminase activity which are typical for long-term space mission. However, these were not accompanied by substantive changes in protein, energy and carbohydrate metabolisms, or intensity of free radical processes. Effects of prolonged stay in chamber was successfully counterbalanced by organism.  相似文献   
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For the selection of compounds affecting the hemorrheologic status a method for reproducing disorders of blood rheologic properties in vitro was developed. It consists in 60-min incubation of blood at 42 degrees C. The hemorrheologic effect of quercetin under such conditions was studied and a dependence of the effect of quercetin on blood viscosity and red cell aggregation on the drug concentration was revealed.  相似文献   
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In the present paper, the application of scanning tunneling microscopy in cytochrome P450s membrane topology is discussed. The method enables visualization of heme location in the lipid-bilayer-incorporated protein. It is supposed that the membrane-bound cytochrome P450 on the tunneling microscope substrate should behave as 'molecular diode'. A model explaining the liposome and the proteoliposome images observed is proposed.  相似文献   
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Fanconi anemia (FA) is a pleiotropic inherited disease that causes bone marrow failure in children. However, the specific involvement of FA genes in hematopoiesis and their relation to bone marrow (BM) failure is still unclear. The increased sensitivity of FA cells to DNA cross-linking agents such as mitomycin C (MMC) and diepoxybutane (DEB), including the induction of chromosomal aberrations and delay in the G2 phase of the cell cycle, have suggested a role for the FA genes in DNA repair, cell cycle regulation, and apoptosis. We previously reported the cloning of the FA group C gene (FAC) and the generation of a Fac mouse model. Surprisingly, the Fac -/- mice did not show any of the hematologic defects found in FA patients. To better understand the relationship of FA gene functions to BM failure, we have analyzed the in vivo effect of an FA-specific DNA damaging agent in Fac -/- mice. The mice were found to be highly sensitive to DNA cross-linking agents; acute exposure to MMC produced a marked BM hypoplasia and degeneration of proliferative tissues and caused death within a few days of treatment. However, sequential, nonlethal doses of MMC caused a progressive decrease in all peripheral blood parameters of Fac -/- mice. This treatment targeted specifically the BM compartment, with no effect on other proliferative tissues. The progressive pancytopenia resulted from a reduction in the number of early and committed hematopoietic progenitors. These results indicate that the FA genes are involved in the physiologic response of hematopoietic progenitor cells to DNA damage.  相似文献   
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