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351.
Buccal smears were analyzed for X chromatin in 1,000 newborn infants. The mean percentage of X chromatin in the 506 female infants was 39.5 (range 19-61) and in the 494 males 0.13 (range 0-3.0). Evaluation of the data comparing the percentage of X chromatin with caucasian and noncaucasian infants, the weight of the newborn, and the gestation time, indicated no significant differences within the male or female populations. A longitudinal study on 25 female infants for the first 4 days postpartum indicated a significant increase in the percentage of X chromatin in females.  相似文献   
352.
Nine endogenous volatile compounds were found in rat brain tissue, and were identified by mass spectrometry as chloroform, a 5-C-aldehyde, dimethyl disulphide, 2,5-dimethyl tetrahydrofuran, a 8-C-alkane, xylene, 2-heptanone, heptaldehyde and 2-n-pentylfuran. Using gas chromatographic and gas chromatographic mass spectrometric techniques, it was established that lithium carbonate did not induce the production of detectable amounts of any new volatile compounds in brain tissue. However, after administration of chloral hydrate, trichloroethanol, a compound not normally present in rat brain tissue, was found to be present.  相似文献   
353.
One hundred twenty-one patients with disseminated malignant melanoma were treated with BCNU, vincristine, DTIC, and chlorpromazine (BVD). A response rate of 22% was observed; 28% of the patients had stable disease and 50% had increasing disease. Similar response rates were obtained with both the high dose and low dose treatment schedules. Patients who exhibited some degree of improvement during their initial course of treatment had the highest overall response rate (72%) to BVD chemotherapy. The median survival from onset of therapy was six months for all patients and 18 months for patients who responded to chemotherapy. The median duration of response was 9.9 months. Thus, the addition of chlorpromazine to BVD chemotherapy did not increase tumor response, and the overall results obtained were comparable to DTIC alone. Patients were found to be lymphopenic prior to the onset of therapy. Their median absolute lymphocyte count was 1800/mm3. Those patients with absolute lymphocyte counts above the 2710/mm3 normal mean had significantly higher response rates (35% vs. 19%, P less than .05) and longer survivals (9.8 months vs. 4.3 months, P less than .05) than patients with lower initial lymphocyte levels. Pretreatment eosinophil and monocyte counts were not closely correlated with patient response or survival.  相似文献   
354.
Based on the selective binding of proteins and DNA to distinct filter materials a double-layered dot blot radio assay was developed to evaluate the binding of DNA to HIV-1 integrase. In this assay the DNA-binding was found to be independent of Mn2+ concentration, inhibited by concentrations of Mg2+ above 5 mM, abolished by zinc chelation and inhibited by monoclonal antibodies reacting with either the N-terminal or C-terminal regions of integrase. Atomic absorption spectroscopy revealed the molar ratio between integrase and zinc to be close to 1. It is concluded that both the N-terminal and the C-terminal regions of integrase are involved in DNA-binding and that the reported double-layered dot blot radio assay is well suited for further characterization of the integrase.  相似文献   
355.
A histologic study was conducted in 5 diabetic and 5 non-diabetic albino rabbits to determine the effect of experimentally induced diabetes upon the number of gingival plasma cells and lymphocytes in the absence and presence of local factors, and IgG, IgM and IgA levels of the four groups were compared with each other. In conclusion, local factors were primarily responsible for the increase of the gingival plasma cells and lymphocytes. There was no statistically significant difference between the diabetic and non-diabetic group in the absence of local factors. Also, there was no marked difference between the serum IgG, IgA and IgM levels of all groups.  相似文献   
356.
Functional dysphonia is a term applied to voice disorders for which there is an absence of apparent structural change in the larynx. The aim of this work was to investigate how functional dysphonia may differ acoustically from other types of dysphonia. Fundamental frequency profiles for steady vowels were generated using a software program called GLIMPES (Glottal Imaging by Processing External Signals). The fundamental frequency variations were found to be unimodal in normal individuals. In contrast, the variations for dysphonic patients were sometimes bi-modal or multi-modal due to the presence of subharmonics or low-frequency modulations. The appearance of these patterns was generally related to the severity of the dysphonia rather than to its etiology.  相似文献   
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BACKGROUND: Hepatic epithelioid hemangioendothelioma (PHEHE) is a multifocal, low-grade malignant neoplasia characterized by its epithelial-like appearance and vascular endothelial histogenesis. The outcome of 16 patients treated with orthotopic liver transplantation (OLT) is the subject of this report. METHODS: A retrospective study of 16 patients with HEHE (7 men, 9 women) with ages ranging from 24 to 58 years (mean 37 +/- 10.6 years). Follow-up intervals ranged from 1 to 15 years (median of 4.5 years). RESULTS: Actual patient survival at 1, 3, and 5 years was 100, 87.5, and 71.3%, respectively. Disease-free survival at 1, 3, and 5 years was 81.3, 68.8, and 60.2%, respectively. The 90-day operative mortality was 0. Involvement of the hilar lymph nodes or vascular invasion did not affect survival. The 5-year survival of HEHE compares favorably with that of hepatocellular carcinoma at the same stage (stage 4A): 71.3 versus 9.8% (p = 0.001) CONCLUSIONS: The long-term survival obtained in this series justifies OLT for these tumors even in the presence of limited extrahepatic disease.  相似文献   
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