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31.
It has been demonstrated that short-term disinfection can affect the surface properties of impression materials. This study evaluated advancing contact angle, receding contact angle, inhibition and mass loss of a polyether impression materials, and two different viscosities of an addition silicone impression material after long-term immersion disinfection (18 hours). The brand names of the impression materials tested were Impregum F, Extrude Extra, and Extrude Wash, and all were tested by use of the Wilhelmy technique; first, for the nondisinfected state, which served as controls, and then after 1 and 18 hours of disinfection in a full-strength solution of acid glutaraldehyde. Weight changes before and after the disinfection process were also measured to detect weight loss and mass change over time. All materials exhibited some degree of inhibition. Polyether lost 0.4% mass in air, which indicated loss of a volatile component. Polyether and addition silicone were both relatively hydrophobic and could be disinfected with acid glutaraldehyde for up to 18 hours without affecting wettability.  相似文献   
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The chromosomal translocation t(11;14)(q13;q32) fuses the IGH and CCND1 genes and leads to cyclin D1 overexpression. This genetic abnormality is the hallmark of mantle cell lymphoma (MCL), but is also found in some cases of atypical chronic lymphocytic leukemia (CLL), characterized by a poor outcome. For an unequivocal assessment of this specific chromosomal rearrangement on interphase cells, we developed a set of probes for fluorescence in situ hybridization (FISH). Northern blotting was performed for analysis of the cyclin D1 expression in 18 patients. Thirty-eight patients, with either a typical MCL leukemic phase (17 patients) or atypical CLL with an MCL-type immunophenotype, i.e., CD19-, CD5+, CD23-/low, CD79b/sIgM(D)++, and FMC7+ (21 patients), were analyzed by dual-color interphase FISH. We selected an IGH-specific BAC probe (covering the JH and first constant regions) and a commercially available CCND1 probe. An IGH-CCND1 fusion was detected in 28 of the 38 patients (17 typical MCL and 11 cases with CLL). Cyclin D1 was not overexpressed in two patients with typical MCL and an IGH-CCND1 fusion. In view of the poor prognosis associated with MCL and t(11;14)-positive CLL, we conclude that this set of probes is a valuable and reliable tool for a rapid diagnosis of these entities.  相似文献   
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PURPOSE: In anticipation of the availability of genetic testing for a breast-ovarian cancer susceptibility gene (BRCA1), this study examined interest in and expectations about the impact of a potential genetic test. PATIENTS AND METHODS: The subjects were 121 first-degree relatives (FDRs) of ovarian cancer patients. The design was cross-sectional. Subjects completed a structured telephone interview of attitudes about cancer and genetic testing, and self-report psychologic questionnaires to assess coping style and mood disturbance. RESULTS: Overall, 75% of FDRs said that they would definitely want to be tested for BRCA1 and 20% said they probably would. In bivariate analyses, interest was associated positively with education, perceived likelihood of being a gene carrier, perceived risk of ovarian cancer, ovarian cancer worries, and mood disturbance. In logistic regression analysis, perceived likelihood of being a gene carrier was associated strongly with interest (odds ratio, 3.7; P = .006). Results of stepwise linear regression modeling indicated that an anticipated negative impact of genetic testing was associated with being younger (beta = -.66, P = .009), having more mood disturbance (beta = .015, P = .01), and having an information-seeking coping style (beta = .19, P = .002). CONCLUSION: These results suggest that the demand for genetic testing for BRCA1 among FDRs of cancer patients may be great. Moreover, those who elect to participate may represent a more psychologically vulnerable subgroup of high-risk women.  相似文献   
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The authors report the results of a six months survey about the low weight of birth (L.W.B.) in the district of Guédiawaye, suburb of Dakar. The purpose is to determine the rate of L.W.B. in two main maternity hospitals of that locality and the associated risk factors. It is a survey with a control group. This survey results in a 10.7% rate, according to the data of another retrospective survey in the same maternity hospitals in 1992 (10.03%). The risk factors are mainly: celibacy, primiparity, an associated pathology with the pregnancy, the physical strain of mothers correlated to the income and to the previous L.W.B.  相似文献   
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The epidemiologic and sociodemographic characteristics of human deficiency virus (HIV) infection vary from one country to another. The objective of this study was to determine the prevalence of HIV infection in pregnant women in Dakar and associated factors. Systematic anonymous screening was performed in pregnant women admitted to the maternity ward. Women whose seropositivity was confirmed by Western blot retroviral serology were included. One woman out of four was assigned by simple random selection to the case control group. Over a 24 month period, 12,498 women were tested. 104 were seropositive (44 HIV1, 58HIV2, and 2 HIV1-HIV2 giving a prevalence of 0.8%. Factors associated with HIV1 and HIV2 were different: mean age 21.7 years for HIV1 versus 30.6 for HIV 2 (p = 0.05); origin in Guinea-Bissau for HIV2 (p = 0.001); mean number of pregnancies 2.6 for HIV1 versus 5.9 for HIV2 (p = 0.001); mean parity 1.5 for HIV1 versus 4.5 for HIV2 (p < 0.01); vitality of the conception product in 85.1% for HIV2 versus 67.5% for HIV1 (p = 0.0001). These data confirm the low prevalence of HIV infection in pregnant women, with a predominance for HIV2. The factors identified in associated with virus type suggest a different mode of transmission and/or reduced virulence or HIV2 compared with HIV1. Knowledge of these factors helps orient management strategies, especially in pregnant women.  相似文献   
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Human cytolytic T lymphocytes specific for autologous Burkitt's lymphoma express the gamma, delta T cell receptor and recognize immunoglobulin idiotype in an MHC-unrestricted manner. Antibodies against a member of the heat shock protein 70 family inhibit this specific cytotoxicity, implicating these molecules in tumor recognition and antigen presentation. Such data is relevant to the design of novel immunotherapies for cancer and provides new insights into target recognition by gamma, delta T cells.  相似文献   
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Wohwe Sambo  Damien  Yenke  Blaise Omer  Förster  Anna  Ndong  Jospeh  Dayang  Paul  Sarr  Idrissa 《Wireless Networks》2022,28(7):3275-3292
Wireless Networks - Nowadays, the exploitation of Wireless Underground Sensor Networks (WUSNs) remains challenging because of the attenuation of wireless underground communications. This issue...  相似文献   
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In this work, load distribution on ball-screw systems (BSS) is determined by experimental techniques. Two optical techniques are used: photoelasticity for stress-field measurement and the mark-tracking method for displacement-field determination. In parallel to the experimental study, finite element method (FEM) and analytical solutions are used to calculate the loads applied on each ball of the BSS. Experimental results are used to validate the choice of boundary conditions and contact conditions between ball-screw and ball-nut in the FEM solution. The validation criterion is the correspondence between numerical and experimental fringes representing the differences of principal stresses. In addition to the study of load distribution, this paper presents the influence of the angle of contact direction on the stress distribution in BSS.  相似文献   
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