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101.
BACKGROUND: The use of self-report screening tests for alcohol use disorders in the primary care setting has been advocated. OBJECTIVE: To test for ethnic and sex bias in three self-report screening tests for alcohol use disorders in a primary care population. DESIGN: Cross-sectional study with patients randomly selected from appointment lists. SETTING: University-based family practice clinic. PATIENTS: Probability sample of 1333 adult family practice patients stratified by sex and ethnicity. MEASUREMENTS: Patients completed 1) a diagnostic interview to determine the presence of a current alcohol use disorder and 2) three screening tests: the CAGE questionnaire, the Self-Administered Alcoholism Screening Test (SAAST), and the Alcohol Use Disorders Identification Test (AUDIT). RESULTS: The areas under the receiver-operating characteristic (ROC) curves for the CAGE questionnaire and the SAAST ranged from 0.61 to 0.88 and were particularly poor for African-American men and Mexican-American women. For the AUDIT, the area under the ROC curves was greater than 0.90 for each patient subgroup. The sensitivity of the CAGE questionnaire and the SAAST at standard cut-points was lowest for Mexican-American women (0.21 and 0.13, respectively). Positive likelihood ratios for the AUDIT were similar to or higher than those for the other screening tests, whereas negative likelihood ratios were lowest for the AUDIT (<0.33), indicating the superiority of this test in ruling out a disorder. CONCLUSIONS: A marked inconsistency in the accuracy of common self-report screening tests for alcohol use disorders was found when these tests were used in a single clinical site with male and female family practice patients of different ethnic backgrounds. The AUDIT does not seem to be affected by ethnic and sex bias.  相似文献   
102.
Loss of sperm motility is associated with the process of sperm senescence and occurs at different rates within a given normal or abnormal sperm population. Reactive oxygen species attack cell membrane phospholipids, generating fatty acid peroxides and other degradation products, that also have deleterious effects on sperm motility and fertilizing ability. The objective of this investigation was to study a modification of the original sperm stress test (MOST), changing the culture medium to one offering transitional metals and shortening the total test time, to ascertain whether it can predict fertilization under these laboratory conditions. A total of 41 semen samples was obtained from patients undergoing in-vitro fertilization (IVF) at our institution. Semen samples were grouped into those producing total fertilization rates (FR) within normal limits (>50%) and those showing low total FR (<50%). The normal FR group had a significantly greater MOST mean value than the low FR group (0.71 versus 0.44). Furthermore, there was a statistically significant correlation between the MOST score and ungrouped fertilization rates (r = 0.53, P = 0.0004). Diagnostic statistics for MOST ratio values predicting <50% FR showed an optimal threshold of 0.39. Collectively, sensitivity, specificity, positive predictive value and negative predictive value have their largest values at this threshold. Taking into account the above mentioned threshold figures, there is a significant association between MOST and FR categories (P = 0.0009). In conclusion, MOST is a simple assay that has significant predictive value for sperm related IVF abnormalities.  相似文献   
103.
The authors briefly report their experience regarding the opportunities offered by the use of current ultrasound methods in carotid surgery. They describe: a system for the quantification of athcromasic plaque used to monitor non-operated patients over time; ultrasound methods used to analyse the carotid wall to establish whether it can be utilised as an index of vascular aggression in hypertension, diabetes and atherosclerosis; the use of transcranial Doppler; criteria for the definition of high risk plaque; the applications of eco-color Doppler. The paper also illustrates a new pathology identified by the authors, defined as primary intimal fibrous hyperplasia, and the evolution of the carotid wall after endarterectomy. The structural characteristics of primary hyperplasia can only be shown using ultrasound given that arteriography cannot distinguish it from atheromatic stenosis. After endarterectomy the carotid wall is subject to hematic and hemodynamic stimuli which determine the type of evolution of the wall itself. The authors therefore examine the myointimal reaction, myointimal hyperplasia, early restenosis and late restenosis as different facets of the same phenomenon.  相似文献   
104.
The objective of this study was to document the influence of specific dietary fatty acids on rates of lipid synthesis and sensitivity to insulin in porcine adipose tissue. Weanling pigs were assigned to one of six groups, and each group was fed diets containing 10 g/100 g of added cornstarch or 10 g/100 g of added fatty acid. The fatty acid-enriched diets contained either a combination of 14:1 plus 16:1 (14:1/16:1 diet), 16:0, 18:0, 18:1, or 18:2 (n-6). With the exception of the cornstarch diet, all diets contained approximately 35% 14:0. Subcutaneous adipose tissue samples were collected at slaughter from the area overlying the first cranial vertebra. Fresh samples were incubated for 2 h in 20 mM glucose and 0, 10, 100 or 1,000 microU/mL of porcine insulin. The smallest adipocytes were observed in adipose tissue from pigs fed the 16:0 or 18:2 diets. Glucose incorporation into lipids was greater (P < .05) in adipose tissue from cornstarch-fed pigs than in adipose tissue from the other treatment groups. Lipogenesis was 67, 53, 35, 32, and 20% lower (P < .05) in adipose tissue from 16:0-, 14:1/16:1-, 18:0-, 18:2-, and 18:1-fed pigs, respectively, than in adipose tissue from the cornstarch-fed pigs. Insulin increased lipogenesis by 19% (P < .05) in adipose tissue from the cornstarch-fed pigs and by 15 to 40% (P < .05) in adipose tissue from the 14:1/16:1-fed pigs. Insulin did not stimulate lipogenesis (P > .4) in adipose tissue from pigs fed the 16:0, 18:0, or 18:1 diets. The data suggest that fatty acid chain length and unsaturation are determinants in the effects of dietary fat and insulin on de novo lipogenesis.  相似文献   
105.
Characterization of the region between HLA-B and the TNF loci in the human MHC revealed the presence of duplicated loci, named CL1 and CL2, that included repeat sequences. Development and use of a PCR typing methodology that amplified both CL microsatellites simultaneously indicated that PCR product patterns analysed on native agarose gels were allelic (Abraham et al., 1992). The purpose of the current study was to determine the molecular explanation for the unique patterns achieved. Sequence analysis of the CL1 locus from 32 chromosomes representing 10 ancestral haplotypes indicated that six alleles were present. The CL microsatellites also provided an opportunity to study the evolutionary relationships between MHC haplotypes from different racial groups. Sequence comparison of closely related ancestral haplotypes from different racial groups suggested that the CL1 microsatellite has not changed in the period since divergence.  相似文献   
106.
107.
High affinity antibodies were used for the quantitative assessment of the miscoding O4-ethylthymine (O4-EtThy) base lesion in nanogram amounts of membrane transblotted restriction fragments of ENU treated DNA. The polyclonal antibody (TB3) specifically recognized attomoles of the alkylation adducts in modified DNA with no cross-reactivity to an excess of unmodified DNA. The sensitivity of the immuno-quantitative method was determined to be in the range of 76 attomoles to 2.43 fmol, corresponding to 0.24 x 10(-7) to 7.9 x 10(-7) adducts per nucleotide in plasmid DNA. Modification levels in ras and tk genes were estimated as 0.025 and 0.014 adducts respectively. Specific antibody binding was proportional to the dose of ENU and size of the DNA fragments. In differentially ethylated ras gene, the amount of O4-EtThy was quantified as 0.026, 0.08 and 0.13 adducts per gene fragment. A DNA concentration dependent antibody binding was observed with large (23.13 and 9.41 kb) and smaller (2.02 kb) fragments of HindIII digested ENU treated phage lambda DNA. To monitor the repair of O4-EtThy lesions in specific segments, damage was assessed in sequences of plasmid DNA established in various Escherichia coli strains. The loss of antibody binding to O4-EtThy adducts in ethylated DNA fragments of 6.4 kb ras gene and 3.6 kb tk gene occurred with an approximate t1/2 of 45 and 35 min, respectively, in the repair proficient wild type E. coli. On the contrary, no repair was seen in the alkyltransferase deficient double mutant ada-ogt- strain. The results specifically demonstrate the sensitivity of the immunological technique and the unique ability of the O4-EtThy specific antibodies to scan this promutagenic base lesion and its repair in very small amounts of selected gene segments in DNA.  相似文献   
108.
BACKGROUND: Hyperthecosis in a postmenopausal woman is a very rare cause of virilization, and only five cases have been reported previously. CASE: A woman presented with a nine-year history of increasing hirsutism and a mild virilization beginning in the perimenopausal period. Initial androgen metabolite concentrations suggested attenuated late-onset adrenal hyperplasia, but a trial of dexamethasone treatment was ineffective. Subsequent use of leuprolide acetate resulted in a biochemical and clinical improvement in the signs and symptoms. CONCLUSION: This case is unique because gonadotropin-releasing hormone agonist administration was utilized as both a diagnostic and therapeutic modality.  相似文献   
109.
The alpha2-adrenergic receptor (alpha2AR) subtype alpha2C10 undergoes rapid agonist-promoted desensitization which is due to phosphorylation of the receptor. One kinase that has been shown to phosphorylate alpha2C10 in an agonist-dependent manner is the betaAR kinase (betaARK), a member of the family of G protein-coupled receptor kinases (GRKs). In contrast, the alpha2C4 subtype has not been observed to undergo agonist-promoted desensitization or phosphorylation by betaARK. However, the substrate specificities of the GRKs for phosphorylating alpha2AR subtypes are not known. We considered that differential capacities of various GRKs to phosphorylate alpha2C10 and alpha2C4 might be a key factor in dictating in a given cell the presence or extent of agonist-promoted desensitization of these receptors. COS-7 cells were co-transfected with alpha2C10 or alpha2C4 without or with the following GRKs: betaARK, betaARK2, GRK5, or GRK6. Intact cell phosphorylation studies were carried out by labeling cells with 32Pi, exposing some to agonist, and purifying the alpha2AR by immunoprecipitation and SDS-polyacrylamide gel electrophoresis. BetaARK and betaARK2 were both found to phosphorylate alpha2C10 to equal extents (>2-fold over that of the endogenous kinases). On the other hand, GRK5 and GRK6 did not phosphorylate alpha2C10. In contrast to the findings with alpha2C10, alpha2C4 was not phosphorylated by any of these kinases. Functional studies carried out in transfected HEK293 cells expressing alpha2C10 or alpha2C4 and selected GRKs were consistent with these phosphorylation results. With the marked expression of these receptors, no agonist-promoted desensitization was observed in the absence of GRK co-expression. However, desensitization was imparted to alpha2C10 by co-expression of betaARK but not GRK6, while alpha2C4 failed to desensitize with co-expression of betaARK. These results indicate that short term agonist-promoted desensitization of alpha2ARs by phosphorylation is dependent on both the receptor subtype and the expressed GRK isoform.  相似文献   
110.
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