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71.
Despite an increased understanding of the potential dangers of benzodiazepines among doctors and patients, and a decline in anxiolytic prescribing, motivating and supporting current benzodiazepine users through withdrawal can be difficult and time consuming for medical services. Self-help organisations offer another approach. This is a study of one such organisation, TRANX (UK), which examined the characteristics of its members and their outcome. The results suggest that this organisation did provide effective counselling and support for its members, and implies that self-help is a realistic alternative or adjunct to orthodox health care for those wishing to withdraw from benzodiazepines.  相似文献   
72.
The characteristics of cell death were investigated after exposure of CCRF-CEM.f2 cells to five drugs over a broad concentration range; these were the glucocorticoid dexamethasone (DXM), the mitotic inhibitor vincristine (VIN) and three antimetabolites, methotrexate (MTX), 5''-fluoro-2''-deoxyuridine (FUdR) and 5''-fluorouracil (5-FU). Drug-treated cells were monitored for cell death mechanisms at different times by examining the pattern of DNA degradation, cell morphology and flow cytometric profile, together with effects on cell growth over 72 h. At growth-inhibitory drug concentrations, the first changes were cell cycle perturbations detectable after 4-6 h of drug exposure. The appearance of features characteristic of apoptotic cell death was noted after all drug treatments in the CCRF-CEM.f2 cell line, but the pattern and kinetics varied considerably. VIN induced apoptotic changes by 12 h, while DXM treatment caused apoptosis only after 48 h. Both MTX and FUdR induced morphological changes characteristic of apoptosis at least 24 h before internucleosomal DNA cleavage, which was detectable only after 48 h. In contrast, 5-FU did not cause internucleosomal DNA cleavage by 48 h at any concentration, despite the presence of morphologically apoptotic cells 24 h earlier. These data suggest that disruption of the cell cycle caused by drug treatment may be the common trigger initiating the drug-specific apoptotic sequence of dying cells.  相似文献   
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The proportion of proliferating tumour cells in a tumour ('growth fraction') was estimated in 30 patients with primary ovarian carcinoma, using monoclonal antibody Ki-67 which reacts with a nuclear antigen present only in proliferating cells. A positive correlation between the 'growth fraction' and both the clinical stage and histological grade of the tumours was observed. A high 'growth fraction' was observed in advanced, metastatic and poorly differentiated tumours and a low 'growth fraction' with early stage, well-differentiated tumours. This information which has not been available previously to clinicians may be of practical value for determining the prognosis, and influencing treatment recommendation.  相似文献   
75.
Forty two patients with inoperable non-small cell lung cancer were entered into a phase II study of the combination chemotherapy regimen PVB (cisplatin 60 mg/m2 by intravenous infusion over two hours on day 1, vinblastine 4 mg/m2 by intravenous bolus on days 1 and 2, and bleomycin 15 mg intramuscularly on days 1, 8, and 15), repeated at three weekly intervals. Twelve of 40 evaluable patients (30%) achieved partial responses; there were no complete responses. The median duration of response was 16 weeks (range greater than 8-73 weeks). The median survival of responding patients calculated from entry to the study until death (40 weeks) was superior to that of patients failing to respond (15 weeks). Treatment was accompanied by signs of moderate toxicity, particularly myelosuppression, nausea and vomiting, alopecia, and neuropathy. One patient died from a neutropenic infection. PVB is a moderately toxic regimen for non-small cell lung cancer and appears similar in efficacy and toxicity to high dose cisplatin and vindesine.  相似文献   
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Patients with maturity onset diabetes that is poorly controlled on maximal doses of oral hypoglycaemic agents are difficult to treat. A prospective randomised crossover study was performed in 58 predominantly non-obese patients on maximal doses of glibenclamide or metformin, or both, to find out if insulin would improve control or well being. The patients were given daily injections of up to 48 units of highly purified porcine lente insulin. Glycaemic control was improved by 15% or more in only 18 patients; 14 others felt better but their diabetes was no better controlled. Those whose control was improved by insulin could not be distinguished by age, duration of diabetes, body mass index, or their own treatment preference. C peptide concentrations, however, did help predict the response to insulin, the fasting C peptide to glucose ratio being considerably lower in those patients whose control was better on insulin. These findings suggest that a simple insulin regimen does not necessarily lead to better glycaemic control in maturity onset diabetes. Nevertheless, a trial of insulin is often justified since it poses few practical difficulties and makes some patients feel better even if their control is not improved. A more complex regimen might improve control in more cases, but it might also be less acceptable to older patients.  相似文献   
78.
The metabolic consequences of deoxyuridine treatment in four cultured human lymphoblast lines (CCRF-CEM, RPMI-8402, JM, and BALM) were studied by cell growth experiments, flow cytometry, and measurement of 2'-deoxyribonucleoside triphosphate (dNTP) levels. DNA perturbations occurred in all lymphoblast lines, but there was no significant impairment of RNA synthesis. The DNA perturbations in CCRF-CEM, RPMI-8402, and BALM cells reflected inhibition of DNA synthesis, and the associated dNTP changes were consistent with ribonucleotide reductase inhibition or, specifically in BALM cells, with DNA alpha-polymerase inhibition. JM cells treated with an intermediate concentration of deoxyuridine developed a block at the G1/S boundary which was deoxyuridine concentration-dependent, but not specific for deoxyuridine (it was also seen with thymidine treatment) and not related to DNA synthesis inhibition. There were no idiosyncratic dNTP effects accompanying the G1/S boundary block, and the responsible metabolic mechanism remains to be determined.  相似文献   
79.
Dietary non-compliance is an important cause of poor metabolic control in insulin dependent diabetes. Patients are often blamed, but teaching methods may be at fault, so a prospective study was set up to compare the effect of three different teaching methods. After a three month run in, 40 adults with longstanding poorly controlled insulin dependent diabetes (mean haemoglobin A1 13.0%) were allocated at random to three teaching methods: conventional diet sheet instruction (group 1); practical lunchtime demonstrations (group 2); videotape education (group 3). Knowledge was assessed by questionnaires, compliance by seven day food records, and glycaemic control by serial glycosylated haemoglobin measurements. During six months of follow up there was no improvement in knowledge, compliance, or HbA1 in group 1, but in groups 2 and 3 both knowledge and compliance improved. In group 2 HbA1 fell to 10.6 (SD 2.1)% and in group 3 to 9.6 (2.3)%. The change in HbA1 showed an appreciable correlation with dietary compliance as judged by day to day consistency in carbohydrate intake. These findings show that new and interesting educational methods can have a major influence on knowledge, compliance, and metabolic control in insulin dependent diabetes.  相似文献   
80.
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