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Abstract  Gastrointestinal stromal tumor (GIST) is a recently described mesenchymal tumor that can develop in any portion of the gastrointestinal tract. The occurrence of a GIST in the urinary tract is rare, but GIST can present as tumor of the urinary tract or invade the urinary tract. This is the first reported case of GIST in the ileal neobladder, which presented as a submucosal tumor. The patient underwent an open exploration and partial resection of the neobladder pouch.  相似文献   
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1 Cytochrome P450-mediated bioactivation of sulphamethoxazole to a hydroxylamine has been implicated in the hypersensitivity reactions associated with co-trimoxazole administration. Inhibiting the formation of the hydroxylamine may be one method of preventing the high frequency of toxicity which is observed in HIV-infected patients. Therefore, in this study, we have investigated the ability of fluconazole and ketoconazole, known cytochrome P450 inhibitors, to inhibit the formation of sulphamethoxazole hydroxylamine.
2 Ten healthy male volunteers were given co-trimoxazole (800  mg sulphamethoxazole and 160  mg trimethoprim) alone or 1  h after either fluconazole (150  mg) or ketoconazole (200  mg) in a randomized fashion with a washout period of at least 1 week between each phase. Urine was collected for 24  h, and sulphamethoxazole and its metabolites were quantified by electrospray LC-MS.
3 Ketoconazole had no effect on the urinary recovery of sulphamethoxazole or any of its metabolites. In contrast, fluconazole significantly ( P <0.001) inhibited the formation of sulphamethoxazole hydroxylamine by 50.0±15.1%. Fluconazole also inhibited the oxidation of sulphamethoxazole to the 5-methylhydroxy and 5-methylhydroxy acetate metabolites by 69.9±15.8% and 64.0±12.0%, respectively, but had no effect on the amount of sulphamethoxazole, N4-acetyl sulphamethoxazole, or sulphamethoxazole N1-glucuronide excreted in urine.
4 The potential clinical benefit of using fluconazole to prevent hypersensitivity to co-trimoxazole in patients with AIDS needs to be assessed in a prospective study using both metabolite formation and the clinical occurrence of adverse reactions as end-points.  相似文献   
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BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer.  相似文献   
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OBJECTIVE: Behavioral disturbances in dementia are extremely prominent and distressful, and often result in serious physical, social, and economic consequences. The authors compared the efficacy and tolerability of risperidone and haloperidol in the treatment of behavioral and psychological symptoms of dementia (BPSD) in institutionalized elderly Korean patients with Alzheimer disease, vascular dementia, or mixed dementia. METHODS: This was an 18-week double-blind, crossover study involving 120 patients who were randomly assigned to receive flexible doses (0.5-1.5 mg/day) of risperidone or haloperidol. BPSD were assessed using the Korean version of the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD-K), the Korean version of the Cohen-Mansfield Agitation Inventory (CMAI-K), and the Clinical Global Impression of Change scale (CGI-C). Safety and tolerability assessments included the Extrapyramidal Symptom Rating Scale and the incidence of adverse events. RESULTS: Both risperidone and haloperidol were efficacious in alleviating BPSD. However, when receiving risperidone, patients showed significantly greater improvement than when receiving haloperidol in the total and subscale scores of the BEHAVE-AD-K, the total and subscale scores of the CMAI-K, and the scores on the CGI-C scale. Also, risperidone had an additional benefit on aggressiveness and anxieties/phobias. The risk of antipsychotic-induced parkinsonism throughout this study was significantly lower with risperidone than with haloperidol. CONCLUSION: Risperidone had a favorable efficacy and tolerability profile compared with haloperidol in the treatment of BPSD in this patient population.  相似文献   
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PHARMACOKINETICS OF MORPHINE FOLLOWING ADMINISTRATION BY THE BUCCAL ROUTE   总被引:1,自引:0,他引:1  
The pharmacokinetics of morphine administered via the buccalroute as a controlled release formulation were assessed afterthe administration of three different doses and found to belinear in the dose range 10–30 µg. The plasma concentrationsof morphine-3-glucuronide and morphine-6-glucuronide demonstratedconsiderable inter-subject variation and conclusions could notbe drawn regarding their pharmacokinetics. These large differencesmay reflect not only variability in buccal absorption, but mayhave resulted from the preparation dissolving in saliva, followedby absorption from the gastrointestinal tract. * Present addresses: Sir Humphry Davy Department of Anaesthetics,Bristol Royal Infirmary Bristol Present addresses: Shackleton Department of Anaesthetics, SouthamptonGeneral Hospital Southampton  相似文献   
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Background Eosinophils are known to be main effector cells in allergic inflammation and IgA antibody has been shown to be a potent stimulus for eosinophil degranulation in in vitro conditions. Objective To evaluate the possible role of IgA antibodies on eosinophil degranulation in lower respiratory mucosa of asthmatics, we tried to find a correlation between total IgA and eosinophil cationic protein (ECP) levels in induced sputum from asthmatics. Methods We measured total IgA and albumin levels by nephelometry, and eosinophil cationic protein levels by Pharmacia CAP system in induced sputum from 23 atopic asthmatics and 12 healthy controls. Results IgA and albumin levels in induced sputum from asthmatics with sputum eosinophilia (sputum eosinophil count 5% of 200 counted non-squamous cells) were significantly higher (P < 0.05) than those from controls. However, IgA and albumin levels in induced sputum from asthmatics without sputum eosinophilia were not significantly different with those from controls (P > 0.05). In induced sputum from asthmatics, ECP levels were significantly correlated with albumin (r= 0.44, P= 0.04) and IgA levels (r= 0.67, P= 0.002). ECP/albumin ratio was also significantly correlated with IgA/albumin ratio (r= 0.61, P= 0.004). Conclusion Our results support the hypothesis that IgA antibodies in tracheobronchial secretion may be involved in eosinophil degranulation in asthma, and further study is needed to prove this hypothesis.  相似文献   
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Immune hypersensitivity to house dust mite antigen (HDM) isa frequent cause of respiratory allergy. The objective of thisstudy was to determine whether exposure to NO2, a common indoorair pollutant, modulates immune responses to HDM and influencesimmune-mediated lung disease. Brown Norway rats were immunizedip with 100 µg semipurified antigen and Bordetella pertussisadjuvant and challenged 2 weeks later with an intratrachealinjection of 50 µg of a crude antigen preparation. Exposureto 5 ppm NO2 for 3 hr after both immunization and challengeprocedures resulted in significantly higher levels of antigen-specificserum IgE, local IgA, IgG, and IgE antibody than air controls,and increased numbers of inflammatory cells in the lungs. Lymphocyteresponsiveness to antigen in the spleen and MLN was also significantlyhigher in NO2-exposed animals. These data show that exposureto a common air pollutant can upregulate specific immune responsesand subsequent immune-mediated pulmonary inflammation.  相似文献   
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To identify the factors that may predict the progression or persistence of untreated mild dysplasia of the uterine cervix, we performed a retrospective review of 118 patients with histologically verified mild dysplasia who underwent colposcopic biopsies between January 1999 and December 2003. Regression to normal occurred in 70.3%, progression to moderate dysplasia or worse occurred in 11.0%, and persistence of mild dysplasia occurred in 18.7%. In regression/progression analysis, progression of untreated mild dysplasia was 34.5% (10/29) in patients with high viral loads (> or =100 relative light units/positive control [RLU/PC]) and 4.5% (3/67) in those with low viral loads (1 to <100 RLU/PC) and negative human papillomavirus (HPV) tests (P < 0.001). Women with high viral loads had a 13-fold greater chance of progression of untreated mild dysplasia than those with low viral loads and negative HPV tests (CI: 2.494-95.297; P = 0.0022). Those associated with both positive smear and positive HPV test (12/45 = 26.7%) were at a greater risk of progression of untreated mild dysplasia as compared with those with positive smear and negative HPV (0/17 = 0.0%) or those with negative smear and positive HPV test (1/18 = 5.6%). Those with high viral loads and both with positive smear and positive HPV test should be followed closely because of their increased risk of progression of untreated mild dysplasia.  相似文献   
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