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51.
There is increasing interest in the therapeutic potential of cannabis-based medicinal extracts in multiple sclerosis. Cognitive deficits that have been attributed to long-term heavy recreational use of cannabis are not necessarily extended to controlled pharmaceutical use of cannabis-based medicinal extracts. Available data indicate that after relatively short-term administration of cannabis-based medicinal extracts no significant cognitive decline occurs. Due to the absence of large scale long-term systematic clinical trials of cannabis-based medicinal extracts in multiple sclerosis therapeutics, however, many issues remain unresolved, including the possible adverse effects of cannabis-based medicinal extracts on cognition. This article critically reviews the current literature and considers the potential for cognitive adverse effects of long-term cannabinoid use in multiple sclerosis therapeutics.  相似文献   
52.
To determine the maximum tolerated doses (MTDs) and dose-limiting toxicities (DLTs) of pegylated liposomal doxorubicin (PLD), paclitaxel (PCX) and gemcitabine (GEM) combination administered biweekly in patients with advanced solid tumours. Twenty-two patients with advanced-stage solid tumours were treated with escalated doses of PLD on day 1 and PCX plus GEM on day 2 (starting doses: 10, 100 and 800 mg m(-2), respectively) every 2 weeks. DLTs and pharmacokinetic (PK) parameters of all drugs were determined during the first cycle of treatment. All but six (73%) patients had previously received at least one chemotherapy regimen. The DLT dose level was reached at PLD 12 mg m(-2), PCX 110 mg m(-2) and GEM 1000 mg m(-2) with neutropaenia being the dose-limiting event. Of the 86 chemotherapy cycles delivered, grade 3 and 4 neutropaenia occurred in 20% with no cases of febrile neutropaenia. Non-haematological toxicities were mild. The recommended MTDs are PLD 12 mg m(-2), PCX 100 mg m(-2) and GEM 1000 mg m(-2) administered every 2 weeks. The PK data revealed no obvious drug interactions. Biweekly administration of PLD, PCX and GEM is a well-tolerated chemotherapy regimen, which merits further evaluation in various types of solid tumours.  相似文献   
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54.
The purpose of the study was to evaluate the use of metabolic phenotype, described by high-resolution magic angle spinning magnetic resonance spectroscopy (HR MAS MRS), as a tool for prediction of histological grade, hormone status, and axillary lymphatic spread in breast cancer patients. Biopsies from breast cancer (n = 91) and adjacent non-involved tissue (n = 48) were excised from patients (n = 77) during surgery. HR MAS MR spectra of intact samples were acquired. Multivariate models relating spectral data to histological grade, lymphatic spread, and hormone status were designed. The multivariate methods applied were variable reduction by principal component analysis (PCA) or partial least-squares regression-uninformative variable elimination (PLS-UVE), and modelling by PLS, probabilistic neural network (PNN), or cascade correlation neural network. In the end, model verification by prediction of blind samples (n = 12) was performed. Validation of PNN training resulted in sensitivity and specificity ranging from 83 to 100% for all predictions. Verification of models by blind sample testing showed that hormone status was well predicted by both PNN and PLS (11 of 12 correct), lymphatic spread was best predicted by PLS (8 of 12), whereas PLS-UVE PNN was the best approach for predicting grade (9 of 12 correct). MR-determined metabolic phenotype may have a future role as a supplement for clinical decision-making-concerning adjuvant treatment and the adaptation to more individualised treatment protocols.  相似文献   
55.
56.

Background  

This paper describes the development of a new quality of life instrument in advanced cancer patients receiving palliative care.  相似文献   
57.
To describe the post-transfusion survival of an entire, geographically defined population, we observed all residents of a US county who underwent perioperative transfusion before and after the introduction of a large autologous transfusion programme. We enrolled 444 and 1540 county residents, transfused in 1981 and in 1986–88, respectively. Complete follow-up (until death or for 5 years) was available on 1960 patients (98.8%). Of patients transfused in 1986–88, 67.6% were alive at 5 years, having survived for a mean (± SE) period of 46.15 (±0.575) months. The survival statistics were 66.2% and 46.09 (±1.047) months, respectively, for patients transfused in 1981 ( P  =0.8424). Transfusion in 1986–88 vs. 1981 (with 615 [40%] vs. six [1.3%] patients receiving some autologous blood) did not have an effect on survival ( P  =0.3892), following adjustment for age, gender, transfusion dose, receipt of a single-unit transfusion and transfusing surgical service. We conclude that the survival of an entire, geographically defined transfused population is substantially longer than that reported previously for patients referred to tertiary-care medical centres. The aggregate 5-year survival of patients transfused in 1981 and in 1986–88 does not differ, despite differences in patient case-mix and in perioperative transfusion practice, particularly as it relates to autologous blood usage.  相似文献   
58.
59.
Over the last 20 years, the Canadian Blood Services' (CBS) Donor Health Assessment Questionnaire (DHAQ), used to screen prospective blood donors to determine their eligibility, has grown in complexity and length. Its growth is inextricably linked to the evolution of the environment within which CBS operates from unregulated collection and distribution of labile blood products to a fully regulated environment and to the need to satisfy both Health Canada and US Food and Drug Administration (FDA) requirements. Within this context, the development of the CBS DHAQ has been characterized by addition of questions and items without any periodic reevaluation of the need for retaining existing questions and/or items. In this review, we apply principles from cognitive science relating to how people think when answering questionnaires to the situation of blood donors completing the DHAQ. We show that some items that were added at different times in separate questions, for reasons that were historically relevant, could be now asked more simply with a single question. The historical development of the DHAQ, resulting in the condensing of many items into lists, the use of complex wording, and the sheer number of items included in the questionnaire make accurate retrieval of information from the donor's memory difficult. Thus, we believe that redesigning the DHAQ will improve the quality and accuracy of the donors' answers to screening questions.  相似文献   
60.

Objective

Identify the psychosocial variables that predict smokers’ compliance with smoke-free policies at work, and non-smokers’ assertiveness for smoke-free rights in Greek and Bulgarian workplaces.

Methods

Data were collected from employees in Greece and Bulgaria. The main outcome measures were smokers’ compliance with smoke-free policies, and non-smokers’ assertiveness intentions. Demographic variables, tobacco use and dependence, as well as beliefs about second-hand smoke (SHS) exposure and smoking at work were also assessed.

Results

Regression analyses showed that smokers’ compliance with smoke-free policies was predicted by age, perceived health risks of smoking, and beliefs related to the benefits of smoking at work. Non-smokers’ assertiveness was predicted by annoyance from exposure to SHS at work, and assertiveness-related social cognitions (e.g., attitudes, social norms, and self-efficacy).

Conclusions

Interventions to promote support for tobacco control policies at work in Greece and Bulgaria may benefit from targeting smokers’ beliefs about the actual effects of tobacco use on health and job performance. Accordingly, efforts to promote non-smokers assertiveness should build stronger assertiveness-related attitudes, convey anti-smoking normative messages, and strengthen self-efficacy skills.  相似文献   
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