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31.
We retrospectively reviewed the cases of seventy-two consecutive patients who had a lumbar discectomy, between 1950 and 1983, when they were sixteen years of age or younger. There were forty boys and thirty-two girls. At the time of the lumbar discectomy, twelve patients (17 per cent) also had a spinal arthrodesis. The mean duration of follow-up was 27.8 years (range, twelve to forty-five years). Twenty patients (28 per cent) had one reoperation or more, with the first reoperation performed at a mean of 9.7 years after the initial discectomy. Fourteen patients had one reoperation, four had two reoperations, one had three, and one had five. Fifty-two patients (72 per cent) did not need a reoperation. At the time of the latest follow-up, forty-eight (92 per cent) of the fifty-two patients either had no pain or had occasional pain related to strenuous activity and fifty-one (98 per cent) could participate in daily activities with no or mild limitations. Survivorship analysis showed that the overall probability that a patient would not need a reoperation was 80 per cent at ten years and 74 per cent at twenty years after the initial operation. With the numbers available for study, we could not show that age, gender, or an arthrodesis performed at the time of the initial operation were risk factors for a reoperation. We could not detect a difference, with respect to pain or the level of activity, between the patients who had had an arthrodesis at the initial operation and those who had not or between those who had a coexisting structural abnormality of the lumbar spine and those who did not.  相似文献   
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Navicula pelliculosa and an associated Flavobacterium sp. were isolated from the epiphyton of Scirpus maritimus, an emergent macrophyte growing in a brackish drainage dyke. Both micro-organisms possessed active transport systems for glucose uptake. In N. pelliculosa the transport system was fully induced in the dark in the absence of glucose, and subsequently inactivated when transferred to the light in the absence of the substrate. The presence of glucose during the dark induction period prevented the achievement of maximum specific activity of the transport system, while incubation at a high light intensity with or without the presence of the substrate resulted in a very marked inhibition of glucose uptake. Inhibition in the light was partially offset by blocking photosynthetic electron flow with 3'(3,4 dichlorophenyl)1'1' dimethyl urea. The transport system accumulated 3-O-methyl glucose against a concentration gradient and was highly specific for glucose as there was no competition by most of the other sugars tested. However, 6-deoxyglucose was taken up instead of glucose and this suggested that glucose was transported in a non-phosphorylated state, whereas inhibition of glucose transport activity with dicyclohexylcarbodimide implicated the involvement of an adenosine triphosphatase on the cell membrane. Inhibitors of oxidative phosphorylation tetrachlorosalicylaniline and carbonylcyanide m-chlorophenylhydrazone also inhibited glucose transport activity. The affinity of the diatom for glucose was greater than that shown by the bacterium, but the Km for glucose transport, 1.5x10-5M was too high to allow effective removal of glucose at in situ concentrations.  相似文献   
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Replies to L. E. Beutler et al (see record 1973-31675-001) who presented data in defense of using the number of patients rather than the number of therapists as the unit of analysis for assessing the reliability of process psychotherapy variables. The present paper presents data suggesting that the Beutler et al interpretation of their research findings is not valid. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Serial examination of magnetic resonance images (MRI) for two months were carried out on two cases of multiple cerebral infarction during the acute stage. The T2-weighted MR images at the onset of the infarction showed both acute (new) and chronic (old) lesions appearing as high signal area. While on the diffusion weighted images only an acute lesion was detected as a high signal area with good contrast. The diffusion coefficient of the acute lesion was lower than that of normal white matter. Diffusion coefficient of the chronic lesions were higher than that of normal white matter. Therefore, on the apparent diffusion coefficient mapping images (ADC images) only an acute lesion appeared as a low signal area. The examination of diffusion images was very useful for distinguishing an acute lesion from a chronic lesion during the acute stage of multiple infarction. The diffusion weighted images after 4 weeks from the onset showed the diffusion coefficient of the "acute" lesion to be the same level of normal white matter. And after 8 weeks from the onset, increased to a level higher than that of normal white matter to the same level of the "chronic" lesion.  相似文献   
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Thirty-nine thyroid nodules, removed because of recent growth, were analyzed morphologically by serial histological sections for the classical histomorphological hallmarks of follicular cell replication and for immunohistochemically demonstrable overexpression of the growth-associated ras-gene product p21ras. Clonal analysis was performed using the highly informative probe M27 beta that detects polymorphisms on the locus DXS255 of the X-chromosome. Twenty-four nodules were of clonal and 15 nodules were of poly-clonal origin. Only 3 out of the 24 clonal nodules were histomorphologically uniform. In all others, the structural hallmarks of active growth and the P21ras growth-marker expression were remarkably heterogeneous throughout the tumors. There were no histomorphological characteristics distinguishing these clonal tumors from polyclonal nodules. Even if a clonal thyroid tumor may be originally homogeneous in respect to the parameters studied here, mechanisms must exist that create wide heterogeneity of growth and of morphogenetic potential among the individual follicular cells during further expansion of the nodule. Thus, clonal nodules are much more common in nodular goiters than hitherto assumed on grounds of the classical morphological criteria. The diagnosis of a true monoclonal nodule can no longer rely on morphological and functional criteria alone but requires molecular or cytogenetic analysis of clonality.  相似文献   
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OBJECTIVES: A randomized trial was conducted to evaluate the effectiveness of a work-site health promotion program in reducing obesity and the prevalence of cigarette smoking. METHODS: Thirty-two work sites were randomized to treatment or no treatment for 2 years. Treatment consisted of health education classes combined with a payroll-based incentive system. Evaluation was based on cohort and cross-sectional surveys. RESULTS: Of 10,000 total employees in treatment work sites, 2041 and 270 participated in weight control and smoking cessation programs, respectively. Weight losses averaged 4.8 lbs, and 43% of smoking participants quit. Net 2-year reductions in smoking prevalence in treatment vs control work sites were 4.0% and 2.1% in cross-sectional and cohort surveys, respectively. No treatment effect was found for weight. Treatment effects for smoking prevalence and weight were both positively correlated with participation rates in the intervention programs (r = .45 for smoking and r = .55 for weight). CONCLUSIONS: This work-site health promotion program was effective in reducing smoking prevalence at a cost that is believed to make the investment worthwhile.  相似文献   
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The specific activity of histamine methyltransferase of rat brain increases rapidly from the 16th until the 25th day of gestation (7 days after birth). The specific activity of phenylethanolamine-N-methyl-transferase shows a rapid increase during the 1st and the 2nd week after birth, the adult values being obtained by the end of the 2nd week.  相似文献   
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