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91.
We examined overall and specific cancer risks among Swedish subjects who had been hospitalised one or more times for psoriasis. A database was created by identifying such patients from the Swedish Hospital Discharge Register and linking them with the Cancer Registry. Follow-up of patients was carried out from the last hospitalisation through 2004. A total of 15 858 patients were hospitalised for psoriasis during 1965–2004, of whom 1408 developed cancer, giving an overall standardised incidence ratios (SIRs) of 1.33. A significant excess was noted for squamous cell skin cancer, and for cancers of the upper aerodigestive tract, oesophagus, stomach, liver, pancreas, lung, kidney and bladder as well as non-Hodgkin lymphoma. Many of these may reflect the effects of alcohol drinking and tobacco smoking. Patients with multiple hospitalisations showed high risk, particularly for oesophageal (SIR 6.97) and skin (SIR 4.76) cancers.  相似文献   
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93.
A nondestructive, real-time acoustic technique for determining elastic properties of compacts during compaction is presented. An acoustic time-of-flight study was conducted, and the extraction of the linear elastic properties of calcium carbonate compacts was demonstrated. To verify the results of the acoustic experiments, a uniaxial compaction investigation was also carried out using a computer-controlled press with an instrumented die. Good agreement between linear elastic properties determined using both acoustic experiments and compaction force-displacement data was observed. This technique has the potential to be used as a real-time compaction monitoring tool.  相似文献   
94.
OBJECTIVES: We wanted to examine reasons for the different incidence trends for cervical squamous cell carcinoma (SCC, declining) and adenocarcinoma (increasing). METHODS: The Swedish Family-Cancer Database on 9.6 million individuals was used to derive incidence trends between 1958 and 1996. Cervical cancers were compared to vaginal and vulvar cancers. RESULTS: A total of 15405 invasive cervical SCCs and 1920 adenocarcinomas were identified. The incidence of SCCs decreased and that of adenocarcinoma increased during the study period, with similar trends among the in situ forms. The incidence of in situ vaginal and vulvar SCC increase 22-fold, whereas, invasive SCC and adenocarcinoma remained unchanged. The age-incidence curves for adenocarcinoma resembled those for SCC before screening, suggesting similar clinical course. CONCLUSIONS: The data suggest that the increase in the incidence of adenocarcinoma is related to an increasing prevalence of human papilloma virus (HPV) infection in female genitals, perhaps in addition to other factors. The increase is not seen in SCC because of effective screening.  相似文献   
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Single chain antibodies (scFv) represent powerful interventional agents for the achievement of targeted therapeutics. The practical utility of these agents have been limited, however, by difficulties related to production of recombinant scFv and the achievement of effective and sustained levels of scFv in situ. To circumvent these limitations, we have developed an approach to express scFv in vivo. An anti-erbB2 scFv was engineered for secretion by eukaryotic cells. The secreted scFv could bind to its target and specifically suppress cell growth of erbB2-positive cells in vitro. Adenoviral vectors expressing the cDNA for the secretory scFv likewise could induce target cells to produce an anti-tumor anti-erbB2 scFv. In vivo gene transfer via the anti-erbB2 scFv encoding adenovirus also showed anti-tumor effects. Thus, by virtue of engineering a secreted version of the anti-tumor anti-erbB-2 scFv, and in vivo expression via adenoviral vector, effective concentrations of scFv were achieved. In vivo gene transfer clearly represents a powerful means to realize effective scFv-based approaches. This method will likely have applicability for a range of disorders amenable to targeted therapeutic approaches.  相似文献   
97.
Approaches to alter the native tropism of adenoviruses (Ads) are beneficial to increase their efficacy and safety profile. Liver tropism is important with regard to potential clinical toxicity in humans. Ad5/3 chimeras in which the Ad5 knob is substituted by the Ad3 knob, such as Ad5/3luc1, have been recently shown to increase infectivity of ovarian cancer cell lines and primary tumor cells, which express low levels of the coxsackie-adenovirus receptor (CAR), without increasing infectivity of liver cells. A novel strategy to address the problem of liver uptake and improve the tumor/liver ratio is genetic replacement of the Ad fiber shaft. Ad5.Ad3.SH.luc1 is an Ad5-based vector that contains the fiber shaft from Ad serotype 3 but the fiber knob from Ad serotype 5. To compare tumor/liver of Ad5.Ad3.SH.luc1 and Ad5/3luc1 in vivo, we created three different tumor and treatment models of ovarian cancer in mice, simulating intraperitoneal and intravenous administration of tumors. Ad5.Ad3.SH.luc1 displayed the lowest liver tropism of all viruses in all models tested. Intravenous administration of all viruses resulted in higher tumor transduction rates compared to intraperitoneal administration. Genetic shortening of the Ad5 fiber shaft significantly increases relative tumor/liver gene transfer. This could improve the effective tumor dose and reduce side effects, thereby increasing the bioavailability of therapeutic agents.  相似文献   
98.
Disruption of genomic integrity due to deficient DNA repair capacity and telomere shortening constitute hallmarks of malignant diseases. Incomplete or deficient repair of DNA double‐strand breaks (DSB) is manifested by chromosomal aberrations and their frequency reflects inter‐individual differences of response to exposure to mutagenic compounds. In this study, we investigated chromosomal integrity in peripheral blood lymphocytes (PBL) from newly diagnosed cancer patients, including 47 breast (BC) and 44 colorectal cancer (CRC) patients and 90 matched healthy controls. Mutagen sensitivity was evaluated by measuring chromatid breaks (CTAs) induced by bleomycin and supplemented by the chemiluminescent measurement of γ‐H2AX phosphorylation in 19 cancer patients (11 BC, 8 CRC). Relative telomere length (RTL) was determined in 22 BC, 32 CRC, and 64 controls. We observed statistically significant increased level of CTAs (P = .03) and increased percentage of aberrant cells (ACs) with CTAs (P = .05) in CRC patients compared with controls after bleomycin treatment. No differences were observed between BC cases and corresponding controls. CRC and BC patients with shorter RTL (below median) exhibited significantly higher amount of ACs (P = .02), CTAs (P = .02), and cells with high frequency of CTAs (≥12 CTAs/PBL; P = .03) after bleomycin treatment. No such associations were observed in healthy controls. γ‐H2AX phosphorylation after bleomycin treatment in PBL did not differ between CRC and BC patients. Our results suggest that altered DSB repair measured by sensitivity towards mutagen in PBL occurs particularly in CRC carcinogenesis. Irrespective of cancer type, telomere shortening may be associated with a decreased capacity to repair DSB.  相似文献   
99.
100.
SIR, Twin and family studies show that susceptibility to RAhas a heritable basis, transmitted in part with some identifiedcandidate genes [1, 2]. As RA patients are at a risk of manycancers [3], a question arises whether RA and cancer share heritablerisk factors, which has not been settled. Most studies haveanalysed the links between RA and lymphohaemato-proliferativediseases, providing some evidence on familial aggregation [4,5]. Family members of RA  相似文献   
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