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181.
Rice bacterial artificial chromosome clones containing centromeric DNA were isolated by using a DNA sequence (pSau3A9) that is present in the centromeres of Gramineae species. Seven distinct repetitive DNA elements were isolated from a 75-kilobase rice bacterial artificial chromosome clone. All seven DNA elements are present in every rice centromere as demonstrated by fluorescence in situ hybridization. Six of the elements are middle repetitive, and their copy numbers range from approximately 50 to approximately 300 in the rice genome. Five of these six middle repetitive DNA elements are present in all of the Gramineae species, and the other element is detected only in species within the Bambusoideae subfamily of Gramineae. All six middle repetitive DNA elements are dispersed in the centromeric regions. The seventh element, the RCS2 family, is a tandem repeat of a 168-bp sequence that is represented approximately 6,000 times in the rice genome and is detected only in Oryza species. Fiber-fluorescence in situ hybridization analysis revealed that the RCS2 family is organized into long uninterrupted arrays and resembles previously reported tandem repeats located in the centromeres of human and Arabidopsis thaliana chromosomes. We characterized a large DNA fragment derived from a plant centromere and demonstrated that rice centromeres consist of complex DNA, including both highly and middle repetitive DNA sequences.  相似文献   
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183.
In the course of an ongoing cohort study on constitutional and occupational risk factors for the development of irritant hand dermatitis in hairdressing apprentices, an increased prevalence of irritant skin changes was noted in a subgroup examined during particularly cold winter months. Prompted by this observation, the importance of several meteorological factors (day means of temperature, relative and absolute humidity) was assessed in extensive statistical analyses based on data of 742 participants, supplemented by meteorological information obtained from the German Meteorological Service (DWD). There were significant associations of existing hand dermatitis with low temperature and low absolute humidity (Mann-Whitney U-test, P < 0.0001), but not with relative humidity (P = 0.38). Logistic regression analysis, including known determinants of irritant hand dermatitis in this setting, showed that low temperature and low relative humidity tended to be risk factors (OR = 1.66 and 1.57, respectively, for the lower quartiles, P = 0.07 in both cases), and confirmed that absolute humidity significantly influenced the occurrence of irritant hand dermatitis (OR = 2.06 for < 4.8 mg/L, P < 0.01). Thus, these environmental factors must be regarded as possible confounders in the analysis of future epidemiological studies on irritant hand dermatitis and should be considered in multifactorial analyses.  相似文献   
184.
Gorlin syndrome is an autosomal dominant disorder characterized by multiple basal cell carcinomas, medulloblastomas, ovarian fibromas, and a variety of developmental defects. All affected individuals share certain key features, but there is significant phenotypic variability within and among kindreds with respect to malformations. The gene (NBCCS) maps to chromosome 9q22, and allelic loss at this location is common in tumors from Gorlin syndrome patients. Two recessive cancer-predisposition syndromes, xeroderma pigmentosum group A (XPAC) and Fanconi anemia group C (FACC), map to the NBCCS region; and unusual, dominant mutations in these genes have been proposed as the cause of Gorlin syndrome. This study presents cytogenetic and molecular characterization of germ-line deletions in one patient with a chromosome 9q22 deletion and in a second patient with a deletion of 9q22-q3l. Both have typical features of Gorlin syndrome plus additional findings, including mental retardation, conductive hearing loss, and failure to thrive. That Gorlin syndrome can be caused by null mutations (deletions) rather than by activating mutations has several implications. First, in conjunction with previous analyses of allelic loss in tumors, this study provides evidence that associated neoplasms arise with homozygous inactivation of the gene. In addition, dominant mutations of the XPAC and FACC1 genes can be ruled out as the cause of Gorlin syndrome, since the two patients described have null mutations. Finally, phenotypic features that show variable expression must be influenced by genetic background, epigenetic effects, somatic mutations, or environmental factors, since these two patients with identical alterations (deletions) of the Gorlin syndrome gene have somewhat different manifestations of Gorlin syndrome.  相似文献   
185.
The present study investigates children's capacity to understand traits in a psychologically meaningful way. Participants included 18 individuals in each of 4 age groups: kindergarten (ages 5-6), 2nd grade (ages 7-8), 5th grade (ages 10-11), and adult. They heard a series of 6 short stories in which a main character performs an action based on a particular motive (positive, negative, or incidental) that results in either a positive or a negative emotional consequence for another character. Participants evaluated each main character and predicted the character's behavior and mental states in different social contexts. Participants in all age groups, even the 5- to 6-year-olds, made trait inferences that were influenced by motive information. These results provide evidence that young children are capable of more sophisticated reasoning about traits than has been suggested previously.  相似文献   
186.
OBJECTIVE: To assess the effect of mixing the insulin analog lispro (Humalog) with NPH (Humulin I) before injection on lispro's fast, short action profile. RESEARCH DESIGN AND METHODS: A total of 12 healthy volunteers received subcutaneous abdominal injections of 0.1 U/kg regular insulin and 0.2 U/kg NPH insulin as follows: lispro and NPH injected separately (treatment group A), lispro and NPH mixed in the syringe up to 2 min before single injection (treatment group B), and human regular insulin and NPH mixed and injected as in group B (treatment group C), on separate occasions, in random order. Plasma glucose was maintained for 12 h by intravenous 20% glucose. Pharmacokinetic and pharmacodynamic parameters were compared by analysis of variance for repeated measures. RESULTS: Peak plasma insulin levels (2.6 +/- 0.8 vs. 2.2 +/- 0.6 vs. 1.9 +/- 0.6 ng/ml, P = 0.075), total glucose infused (121.5 +/- 32.8 vs. 135.0 +/- 49.0 vs. 117.3 +/- 39.9 mg.kg-1.min-1, P = 0.53), and maximum glucose infusion rate (GIRmax) (8.3 +/- 0.9 vs. 8.0 +/- 1.7 vs. 7.1 +/- 2.4 mg.kg-1.min-1, P = 0.65) were not significantly different between treatments. The times until peak insulin concentrations were similar in treatment groups A and B, but significantly shorter than in treatment group C (0.9 +/- 0.3 and 1.2 +/- 0.2 vs. 2.0 +/- 0.4 h, respectively, P = 0.042). The times until GIRmax were also not different (113.9 +/- 41 and 122.0 +/- 45 vs. 209.0 +/- 51.3 min, respectively, P = 0.002). The glucose infusion rate (GIR) then fell to 50% GIRmax more quickly in treatment groups A and B than in treatment group C (239.9 +/- 40.5 vs. 292.4 +/- 133.3 vs. 399.5 +/- 78.3, respectively, P = 0.005). CONCLUSIONS: The action profile of lispro is not attenuated by mixing lispro with NPH in the syringe immediately before injection. The advantages are available to those individuals who need to combine types of insulin before injection to achieve optimal diabetes control.  相似文献   
187.
V-Effects of thrombolytic therapy on coronary reperfusion and left ventricular function VI-Noninvasive markers of reperfusion. VII-Timing of thrombolysis. VIII-Side effects and adverse outcomes.  相似文献   
188.
BACKGROUND: The natural history of patients with intraductal carcinoma (DCIS) and microinvasion is poorly defined, and the clinical management of these patients, with particular reference to management of the axilla, has been controversial. Previous studies of this lesion have used varied and/or arbitrary criteria for the evaluation of microinvasion. METHODS: Thirty-eight DCIS lesions with microinvasion (n=29) or probable microinvasion (n=9), diagnosed during the period 1980-1996, were retrospectively analyzed after cases not treated with mastectomy and axillary lymph node dissection were excluded. Microinvasion was defined as a single focus of invasive carcinoma < or = 2 mm or up to 3 foci of invasion, each < or =1 mm in greatest dimension. RESULTS: The patients were all females with a mean age of 56.4 years. DCIS was of comedo (n=31) or papillary (n=7) subtype. Microinvasion was often associated with an altered, desmoplastic stroma (55%) or a lymphocytic infiltrate (39%). The foci of microinvasion ranged from 0.25 to 1.75 mm (mean, 0.6 mm), with an aggregate mean size of 1.1 mm (range, 0.25-2.25 mm). Foci of microinvasion, ranging from 1 to 3 (mean, 1.7), were adjacent to DCIS in 95.3% of cases. The extent of DCIS did not correlate with the number of foci of microinvasion. Axillary lymph node dissections yielded a mean of 19.3 lymph nodes (range, 7-38), and all lymph nodes were negative for metastasis. None of 33 patients, followed for a mean of 7.5 years (range, 1.0-14.4 years), developed local recurrence or metastasis. CONCLUSIONS: The cases of microinvasive carcinoma examined in this study, as defined above, were not associated with axillary lymph node metastases and appeared to be associated with an excellent prognosis. Further study is indicated to determine the appropriate management and long term prognosis of patients with this lesion.  相似文献   
189.
Peptide vaccination against tumor Ags can induce powerful systemic CTL responses. However, in the majority of patients, no tumor regression is noted. To study this discrepancy, we analyzed CTL reactivity in a melanoma patient (F001) vaccinated with g209-2M peptide, a single residue variant of gp100(209-217). G209/g209-2M-reactive CTL were identified in post- but not prevaccination PBL. Limiting dilution analysis identified one predominant CTL clone (C1-35), with TCR Vbeta6s2, recognizing g209/HLA-A*0201-expressing targets. Additionally, two autologous melanoma lines (F001TU-3 and -4) and 20 separate tumor-infiltrating lymphocyte cultures were generated from a fine needle aspirate of a metastatic lesion progressing after initial response to vaccination. Both F001TU did not express gp100 and were not recognized by C1-35. Loss of gp100 by F001TU correlated with a marked reduction of gp100 expression in the same metastatic lesion compared with prevaccination. Thus, ineffectiveness of C1-35 and tumor progression could be best explained by loss of target Ag expression. Interestingly, 12 of 20 tumor-infiltrating lymphocyte cultures recognized F001TU, but none demonstrated g209/g209-2M reactivity, suggesting a functional dissociation between systemic and local immune response. This study suggests that vaccination effects must be analyzed in the target tissue, rather than in the systemic circulation alone.  相似文献   
190.
OBJECTIVE: Our objective was to study the ability of three-dimensional MR angiography with retrospective respiratory gating to reveal stenoses in proximal coronary arteries on source and projection images. CONCLUSION: Proximal coronary artery stenoses can be identified using three-dimensional MR angiography with retrospective respiratory gating, both with projection images and on source images alone. Reasons for missed lesions included collateral vessels and retrograde flow distal to complete occlusion and volume averaging of vessels with adjacent structures. Causes of false-positive interpretations included small foci of decreased signal intensity distal to complete occlusion, partial volume effects on individual partitions, and regions of distal vessels leaving the imaging plane.  相似文献   
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