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161.
Studies on the wake-sleep cycle with participation of eight female volunteers were performed before, during, and after a 120-day bed rest with the head-end of bed tilted down at 6 degrees (HDT). Methods of polysomnography and actography were applied. The test-subjects were assigned into 2 groups. Group A was prescribed to use countermeasures throughout the experiment; no countermeasures was administered by group B. Evidence of significant alteration in sleep structure at different time points in HDT is given in comparison with data about females of the control group under the conditions of everyday activity. Sleep deviations in the subjects were reordered at each of the three points of investigation and differed from those in control. HDT was shown to modify the sleep structure in experimental groups A and B. A supposition is made that under these conditions the dynamics of physical activity during night sleep had an adaptive character.  相似文献   
162.
A case is made for setting up a new certificate program "Medical Physics". This would take care of specialists certified in physics and applied technological disciplines who work in hospitals and, particularly, radiological wards. The Association of Medical Physicists of Russia, established in 1991, is making a considerable contribution to the training of medical physicists in full conformity with recommendations of international organization and agencies.  相似文献   
163.
We cloned the MLSB resistance determinant by PCR from a clinical isolate of Enterococcus faecalis 373, which is induced more strongly by a 16-membered-ring macrolide, tylosin, than by erythromycin. To elucidate the molecular basis of resistance of E. faecalis 373, we analyzed the cloned gene, designated ermAMR, by site-directed mutagenesis and reporter gene assay. Our results showed that an arginine-to-cysteine change in the seventh codon of the putative leader peptide endowed tylosin with resistance inducibility and that TAAA duplication enabled the control region to express the downstream methylase gene at a drastically increased level.  相似文献   
164.
The susceptibility testing methods used in Denmark were evaluated with respect to their ability to detect cephalosporin resistance with cefuroxime as indicator, especially resistance caused by extended-spectrum beta-lactamases (ESBLs). Two methods for determination of minimal inhibitory concentration (MIC), three agar diffusion methods, a disc approximation test and the ESBL-Etest were used against a panel of strains producing well-known beta-lactamases. The tablet diffusion test (Rosco Neo Sensitabs) as the most used in Denmark had the lowest detection rate of cefuroxime resistance among ESBL-producing strains. The prediffusion method, which is only used at one laboratory, was the most reliable method for such detection. The MIC methods were in good agreement, but the detection rate for resistance due to ESBLs was low and depended on the antibiotics used. The disc approximation test and the ESBL-Etest both resulted in an acceptable ESBL detection rate. The latter tests discriminated between isolates producing the frequent chromosome-mediated and the in Denmark probably very rare ESBL-mediated cephalosporin resistance. For the evaluation of susceptibility tests such strains require special attention.  相似文献   
165.
Using mutant strains of Rhodobacter capsulatus and Rhodobacter sphaeroides in which the pufX gene had been deleted, it was possible to identify by HPLC membrane protein components present in pufX+ cells but absent in pufX- cells. In parallel preparations, membrane proteins soluble in chloroform/methanol containing ammonium acetate were first extracted from lyophilized membrane fractions of the pufX+ cells and separated from pigments and larger protein material by gel-filtration chromatography. Protein-containing fractions were examined by HPLC, and several peaks were collected from pufX+ material that were not present in pufX- material. From N-terminal amino acid sequencing, the PufX protein of Rb. capsulatus was identified, and from positive interaction with a PufX protein antibody, the Rb. sphaeroides PufX protein was identified. Although overall yields were very small, sufficient quantities of these proteins were isolated to evaluate their effect on the reconstitution of the core light-havesting antenna (LH1) and its subunit complex. From the behavior of the PufX protein and the alpha-polypeptide of LH1 on HPLC, qualitative evidence was obtained that the two proteins have a high affinity for each other. In reconstitution assays with bacteriochlorophyll (Bchl) and the LH1 alpha- and beta-polypeptides of Rb. capsulatus, the PufX protein of Rb. capsulatus was inhibitory to LH1 formation at low concentration. A similar inhibition was exhibited by Rb. sphaeroides PufX protein for reconstitution of LH1 with Bchl and the LH1 alpha- and beta-polypeptides of Rb. sphaeroides. In both cases, the ratios of concentrations of the PufX protein to the alpha-polypeptide causing 50% inhibition were approximately 0.5. Formation of the heterologous (alpha beta) subunit-type complex formed with Bchl and the alpha- and beta-polypeptides of LH1 of Rb. capsulatus was also inhibited by low concentrations of the Rb. capsulatus PufX protein (approximately 50% inhibition at PufX:alpha-polypeptide ratios = 0.5). However, neither PufX protein inhibited formation of a homologous (beta beta) subunit-type complex, which indicates that the PufX proteins do not interact with the beta-polypeptides.  相似文献   
166.
167.
An unusual case of cerebral toxoplasmosis leading to a fatal vehicular crash is presented. Massive intracerebral hemorrhage, a rare complication of cerebral toxoplasmosis in persons with acquired immunodeficiency syndrome (AIDS), caused sudden onset of increased intracranial pressure that led to loss of control of the vehicle and an ensuing fatal traffic crash.  相似文献   
168.
This article describes the long-term consequences of successful cardiovascular disease (CVD) prevention and its influence on premature mortality in Finland, with special reference to North Karelia. Active community-based CVD prevention began in 1972 in the province of North Karelia (population, 180,000). Since 1977, active preventive work has been carried out nationwide, taking advantage of the experience from North Karelia, which continued as a demonstration area for integrated prevention of noncommunicable diseases. Comprehensive community-based interventions as part of WHO interhealth and CINDI programmes in North Karelia and nationwide aimed at changing the target risk factors and health behaviours (serum cholesterol, blood pressure, smoking, diet) at the population level. Age-adjusted mortality rates for CVD, coronary heart disease (CHD), cerebrovascular disease, all cancers, lung cancer, accidents and violence, and all causes in the population aged 35-64 years from the pre-programme period (1969-71) to 1995 were the main measures of the outcome. Among men there was a great reduction in deaths from CHD, CVD, cancer, and all causes in the whole country. From 1969-71 to 1995 the age-standardized CHD mortality (per 100,000) decreased in North Karelia by 73% (from 672 to 185) and nationwide by 65% (from 465 to 165). The reduction in CVD mortality was of the same magnitude. Among men, CHD mortality decreased in the 1970s, as did lung cancer mortality in the 1980s and 1990s, significantly more in North Karelia than in all of Finland. Among women there was a great reduction in CVD (including CHD and stroke) mortality and all-causes mortality, but only a small reduction in cancer mortality. These results show that a major reduction in CVD mortality among the working-age population can take place in association with active reduction of major risk factors, with a favourable impact on cancer and all-causes mortality.  相似文献   
169.
We have isolated a novel human C-C chemokine, MIP-1 delta from a human fetal spleen cDNA library. The human MIP-1 delta cDNA has an unusually long 400-bp 5-prime untranslated region and a predicted 113-amino acid protein of 10 kDa. The coding sequence contains a signal peptide of 21 amino acids, indicating that the mature protein has 92 amino acids (8 kDa). Recombinant human MIP-1 delta produced by transfected human embryonic kidney 293 cells produced an 8-kDa protein, which confirmed the presence of a signal peptide. Compared with other human C-C chemokines, human MIP-1 delta shows the highest homology with human HCC-1, CK beta-8, murine C10, and CCF18 (MIP-1 gamma). The human MIP-1 delta gene is localized on chromosome 17 where most of the C-C chemokine superfamily is located. Human MIP-1 delta is expressed in T and B lymphocytes, NK cells, monocytes, and monocyte-derived dendritic cells, but not in bone marrow-derived dendritic cells. Its expression can be induced by other proinflammatory cytokines in monocytes and dendritic cells. Human MIP-1 delta is chemotactic for T cells and monocytes, but not for neutrophils, eosinophils, or B cells. Human MIP-1 delta induced calcium flux in human CCR1-transfected cells.  相似文献   
170.
OBJECTIVE: Before balloon dilation, failure of compensatory enlargement and even arterial shrinkage are frequently observed at the lesion site in response to plaque accumulation. Balloon angioplasty may be regarded as artificial remodeling to enlarge the artery. The prevalence of the different types of arterial wall remodeling after applied stretch by balloon angioplasty is unknown. METHODS AND RESULTS: In 181 patients an intravascular ultrasound study was performed after coronary balloon angioplasty (n = 200 lesions). The vessel area was measured at a proximal and distal reference site and at the lesion site. Subsequently, the relative vessel area [(Vessel area lesion site)/Vessel area reference site) x 100] was calculated. Lesions were classified in three groups on the basis of their relative vessel areas: > or =105%, <105% but >95%, and < or =95%. A relative vessel area > or =105%, indicating enlargement compared with the reference site, was observed in 84 (44%) lesions. A relative vessel area <105% but >95% was observed in 43 (22%) lesions. A relative vessel area < or =95%, indicating "shrinkage" compared with the reference site, was observed in 66 (34%) lesions. CONCLUSIONS: After balloon angioplasty, the vessel area was found to be smaller compared with the reference site in 34% of the lesions. This small vessel area at the lesion site compared with a reference site may be a reflection of insufficient stretch by balloon angioplasty.  相似文献   
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