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981.
982.
983.
Up to now, only glucocorticoids were thought to act on the renal proximal Na+/H+ exchanger. Using fluorimetric techniques we studied the kinetics of Na+/H+ exchange in brush border vesicles from ADX rats treated with increasing doses of corticosterone (B) and 18-hydroxycorticosterone (18OHB). Significant linear correlations were obtained when the Vmax of each treatment were plotted against log doses. 18OHB exhibits a slightly higher sensitivity than B and log-dose responses were steeper for 18OHB than for B treated rats. Differences between both treatments were highly significant at the 4.8 microg/100 g level, corresponding to the physiological blood level of 18OHB. Physiological doses of both steroids elicited equal Na+/H+ exchange-responses. 18OHB is not a glucocorticoid since even 88 microg/100 g did not promote hepatic glycogen deposition while the same dose of B increases glycogen deposits 3.5-fold. These results demonstrate the importance of the Na+/H+ exchanger as a mediator between corticoid action and H+ transport and that of the non-glucocorticoid 18OHB in this process.  相似文献   
984.
Unknown proteins isolated from mutant tissues of rice (Oryza sativa L.) recovered from inhibitor selections were subsequently peptide microsequenced. Database searches putatively identified one peptide as fructose 1,6-bisphosphate aldolase (EC 4.1.2.13). Tissues of mutant rice, PI564784, and wild type (cv Calrose 76) tissues were evaluated for aldolase activity. Total enzyme activities were slightly lower in the mutant than the control but the differences were not significant. Although the mutant phenotype is for enhanced lysine and protein, we ascribe the small aldolase differences to physiological adjustments, rather than to DNA modifications of the aldolase gene(s). Homologies of rice peptides with aldolases from a range of species, as well as rice cell culture expressed sequence tags (ESTs) are presented. Some amino acids sequences are highly conserved. The mutant phenotype expressing stress proteins is not likely to be defined by a change in rice aldolases.  相似文献   
985.
986.
OBJECTIVE: To examine the impact of ethnic group on aspects of weight concern and to assess the role of family values in explaining this association. SUBJECTS AND MEASURES: 20 Asian and 20 white daughters gave a questionnaire to their mother, father and sibling closest in age, concerning their profile characteristics (age, education) values and beliefs and completed a matched questionnaire containing additional measures of aspects of their weight concern. RESULTS: The results showed no differences between the white and Asian daughters in terms of either their restrained eating or body dissatisfaction. However, the results showed consistent differences between the members of the two family groups in terms of the value placed on achievement, child/parent relationships, competition, the role of women, and some differences in terms of materialism, the value of appearance and their idea of the perfect female body. The results were then analysed to assess the best predictors of the daughter's weight concern. Whereas restrained eating was related to the mother's rating of the value of physical appearance and the sibling's ratings of competitiveness and a non-traditional role for women (40% of the variance), the results showed that body dissatisfaction was related to the daughter's rating of materialism, having a father who preferred a thinner female body, the siblings ratings of a non-traditional role for women, degree of concordance within the family concerning the value of competitiveness and the educational level of the 'head of the family' (49% of variance). CONCLUSION: Whereas a dichotomous model of ethnicity may be insufficient to explain differences in aspects of weight concern, an expanded model of cultural beliefs may be a more powerful construct. Accordingly, the absence or presence of differences in weight concern according to ethnic group may simply reflect the extent to which the different groups chosen for analysis are differentiated by these predictive values.  相似文献   
987.
PURPOSE: To determine whether patients with early-stage bilateral breast cancer can be treated with definitive irradiation following breast-conserving surgery with acceptable survival, local control, complications, and cosmesis. METHODS AND MATERIALS: During the period 1977-1992, 55 women with Stage 0, I, or II concurrent (n = 12) or sequential (n = 43) bilateral breast cancer were treated with definitive irradiation following breast-conserving surgery. The records of these 55 patients with 110 treated breasts were reviewed for tumor size, histology, pathologic axillary lymph node status, first and overall site(s) of failure, and adjuvant chemotherapy or hormonal therapy. Curves for survival, local control, and regional control were determined. Cosmetic outcome, complication rates, and matching technique were analyzed. The median total radiation dose delivered was 64 Gy (range 42-72) using tangential whole-breast irradiation followed by an electron or iridium implant boost. The tangential fields were matched with no overlap in 40 patients (73%); there was overlap on skin of up to 4 cm in 14 patients (25%); and the matching technique was unknown in 1 patient (2%). The median follow-up for the 12 women with concurrent bilateral breast cancer was 4.0 years. The median follow-up for the other 43 women with sequential cancer was 9.3 and 4.9 years, respectively, after the first and second cancers. RESULTS: For the overall group of 55 patients, the 5- and 10-year overall survival rates were 96% and 94%, respectively, after treatment of the first cancer, and 96% and 92%, respectively, after treatment of the second cancer. The 5- and 10-year actuarial relapse-free survival rates were 90% and 75%, respectively, after treatment of the first cancer, and 83% and 72%, respectively, after treatment of the second cancer. For the 110 treated breast cancers, the 5- and 10-year actuarial local failure rates were 5% and 15%, respectively. Complication rates were: 28% breast edema, 8% arm edema, 4% pneumonitis, 3% cellulitis, 1% rib fracture, and 1% brachial plexopathy; no patient developed matchline fibrosis. For patients with a minimum of 3 years of relapse-free follow-up, the rate of excellent or good cosmetic outcome for 104 treated breasts was 85%. CONCLUSION: Definitive irradiation after breast-conserving surgery is technically feasible for selected patients with concurrent or sequential early-stage bilateral breast cancer. Survival, local control, complication rates, and cosmetic outcomes appear comparable to historical reports of breast conservation treatment for unilateral disease. Bilateral definitive breast irradiation after breast-conservation surgery should be considered an acceptable alternative treatment to bilateral mastectomy for selected patients with concurrent or sequential early-stage bilateral breast cancer.  相似文献   
988.
The APOE epsilon4 allele is a strong genetic susceptibility factor for Alzheimer's disease. Interaction with other biological factors may modulate the effect of the apoE isoforms. However, previous work suggested that other genetic variability within the APOE locus, influencing the effect of the epsilon4 allele, may exist. Such variability could modify the expression of the APOE gene and, in particular, the level of expression of APOE alleles could be an important determinant of disease pathogenesis. To test this hypothesis we examined the levels of expression of APOE in heterozygotes with AD and in controls, using a new method of semi-quantitation. We report that relative epsilon4 mRNA expression is increased in AD compared with controls and suggest that genetic variability in the neural expression of APOE contributes to disease risk.  相似文献   
989.
Cytotoxin production was studied in 60 Serratia marcescens strains isolated from hospitalized patients. Association of cytotoxic activity with serotype, source of isolation and presence of plasmids was also evaluated. Thirteen of the 60 S. marcescens strains produced a cytotoxic effect on Vero cells. These strains were isolated from distinct clinical sources and classified into seven different serotypes (O1:H7; O4:NM; O10:NT; O19:NM; O6,14:H4; O6,14:NM and O6,14:H1). No relationship was observed between cytotoxic activity and clinical source or serotypes of the strains. Plasmids from five cytotoxin-producing S. marcescens strains were transferred to E. coli K12/711. The transconjugants did not exhibit cytotoxicity, indicating that the cytotoxic effect is not plasmid-mediated among these strains. Although a cytotoxic activity was demonstrated in filtrates of some S. marcescens strains, further studies should be performed to assess the role of this toxin in pathogenesis.  相似文献   
990.
Allergic bronchopulmonary aspergillosis (ABPA), occurring primarily in patients with asthma or cystic fibrosis (CF), is a hypersensitivity reaction to Aspergillus fumigatus (Af), and is characterized by increased serum IgE levels and peripheral blood and pulmonary eosinophilia. We evaluated the IgE and cytokine profile in ABPA through enzyme-linked immunosorbent assay (ELISA), and evaluated eosinophil activity with the eosinophil peroxidase (EPO) assay. IgE and cytokines were measured in supernatants from cultures of peripheral blood mononuclear cells (PBMC) from three subject groups: ABPA patients, patients with asthma, and healthy individuals. All cultures for the three subject groups were studied in the presence and absence of two purified Af antigens (the 35-kD antigen and heat shock protein 1). We found that increased in vitro levels of IgE in unstimulated PBMC culture supernatants correlated significantly with serum IgE concentrations in ABPA patients. We measured a decrease in IgE levels of up to 75% of baseline values in supernatants from PBMC cultured with Af antigens. Interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) concentrations in cultures with Af were increased in ABPA, whereas concentrations of IL-4 did not differ in the three subject groups. An inverse relation was noted between the changes in IgE and IFN-gamma measured in 4 of 5 ABPA patients. The PBMC supernatants also promoted EPO activity in purified eosinophils from ABPA patients, and to a lesser extent in purified eosinophils from healthy subjects. These results show that the 35-kD antigen and HSP1 from Af downregulate IgE in vitro but are capable of inducing eosinophilia in ABPA. Further studies could result in the characterization of epitopes leading to these disparate effects. An identification of the IgE-down-regulating epitopes in Af antigens might have therapeutic significance.  相似文献   
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