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991.
BACKGROUND: The aim of this study was to provide evidence about the individual intention to quit smoking and accompanying characteristics in a country with a low amount of tobacco control (TC) provisions. METHODS: This study used a random sample of the population aged 18-64 in a German area to make a quantitative estimation of the stages of change to quit smoking among current smokers who had at least one quit attempt (n = 1075). RESULTS: The rate of those who did not intend to stop smoking (precontemplators) was 76.4%, that of those who intended to quit during the next 6 months (contemplators) was 17.0%, and that of those who intended to quit during the next 4 weeks was 6.6%. The three groups did not differ according to gender or age. Of those who had at least 16 years of education, more were contemplators than were those with fewer years of education. Among those who had somatic complaints or nausea from smoking, who had their first cigarette within 1 h or less after awakening, and who had more quit attempts, more were in the contemplation or preparation stage. CONCLUSIONS: Nicotine dependence may add to contemplating about quitting. The precontemplation rate was substantially higher than in samples from nations or states which show a large amount of TC provisions.  相似文献   
992.
In addition to tobacco and alcohol consumption, pollutants found in certain industries and in the environment play an important role in carcinogenesis in the upper aerodigestive tract. The aim of the present study was to investigate whether vanadium pentoxide may have a genotoxic effect on human mucosal cells and lymphocytes. The single cell microgel electrophoresis assay (Comet assay) was used to detect DNA damage induced by vanadium pentoxide in human nasal epithelia (n = 11) and in lymphocytes (n = 11). Mucosa was harvested from inferior nasal turbinates, while lymphocytes were obtained via venous puncture. Vanadium pentoxide was applied at concentrations of 0.06 mM, 0.12 mM, 0.24 mM, and 0.47 mM. Aqua bidestillata served as solvent and negative control and N-methyl-N'-nitro-N-nitrosoguanidine at 0.07 mM (MNNG) was used as positive control. The trypan blue exclusion test was applied to assess cytotoxicity. Whereas vanadium pentoxide induced dose-dependent DNA migration in lymphocytes, mucosal cells did not show comparable genotoxic effects. Cytotoxic effects allowed for viabilities exceeding 80%. The results indicate that vanadium pentoxide is capable of inducing single-strand-breaks and/or alkali-labile damage in the DNA of human lymphocytes. By contrast, mucosal cells proved not to be sensitive in this setting. Thus, a possible role of vanadium in the tumorigenesis of head and neck cancer appears unrelated to direct genotoxic effects.  相似文献   
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Scimitar syndrome has a variable presentation depending on the age at which the diagnosis is made. We report a case of a young woman (age 18 years) with suspected right pulmonary hypoplasia in whom a scimitar syndrome was diagnosed. Using MRI morphological findings and hemodynamic significance of the syndrome were assessed. Left-to-right shunt was calculated from blood flow measurements performed in the ascending aorta, the main pulmonary artery, and the aberrant scimitar vein.  相似文献   
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BACKGROUND: Previous data indicate that a transfer of specific humoral and cellular immunity by way of allogeneic hematopoietic cell transplantation (HCT) should, in principle, be possible. METHODS: In the HCT setting with a follow-up of up to 55 months, we studied the transfer of hepatitis B virus (HBV) specific immunity from electively immunized donors into HLA compatible recipients suffering from chronic myeloid leukemia (CML). After excluding preexisting HBV specific immunity in donor-recipient pairs, 27 prospective donors were vaccinated against HBV. In addition, on an average of 22 months postHCT, 8 of the 19 recipients were immunized once for HBV. RESULTS: Donor vaccination resulted in detectable hepatitis B surface (HBs) antibodies in 85% of donors and specific cellular in vitro responses in 77%. Two weeks postHCT, 86 and 67% of the recipients displayed positive humoral and cellular HBV reactions, respectively, which then decreased. Afterwards, HBV immunity reappeared in 83% of the recipients without revaccination. Following a single vaccination in recipients, seven of eight displayed a typical memory response. An HBV specific response was already detectable 1 week after vaccination, approximately 1,300-fold (humoral) and 60-fold (cellular) higher than observed in the corresponding donors after a single immunization. CONCLUSIONS: The "spontaneous" recurrence of HBV immunity and the memory response in recipients give evidence for an elective immune transfer (e.g., for viral antigens) by way of allogeneic HCT.  相似文献   
999.
Expression profiling of RNAs or proteins has become a promising means to investigate the heterogeneity of histopathologically defined classes of cancer. Peptides, representing degradation as well as processing products of proteins offer an even closer insight into cell physiology. Peptides are related to the turnover of cellular proteins and are capable to reflect disease-related changes in homoeostasis of the human body. Furthermore, peptides derived from tumor cells are potentially useful markers in the early detection of cancer.In this study, we introduced a method called differential peptide display (DPD) for separating, detecting, and identifying native peptides derived from whole cell extracts. This method is a highly standardized procedure, combining the power of reversed-phase chromatography with mass spectrometry. This technology is suitable to analyze cell lines, various tissue types and human body fluids. Peptide-based profiling of normal human mammary epithelial cells (HMEC) and the breast cancer cell line MCF-7 revealed complex peptide patterns comprising of up to 2300 peptides. Most of these peptides were common to both cell lines whereas about 8% differed in their abundance. Several of the differentially expressed peptides were identified as fragments of known proteins such as intermediate filament proteins, thymosins or Cathepsin D. Comparing cell lines with native tumors, overlapping peptide patterns were found between HMEC and a phylloides tumor (CP) on the one hand and MCF-7 cells and tissue from a invasive ductal carcinoma (DC) on the other hand.  相似文献   
1000.
PURPOSE: We evaluated the toxicity and feasibility of adding paclitaxel to a standard platinum/etoposide regimen in the first-line treatment of patients with small cell lung cancer (SCLC). PATIENTS AND METHODS: Eighty-nine patients with limited disease (LD) or extensive disease without distant metastases (ED I) were treated in this multi-centered phase II trial between April 1996 and June 1997. Paclitaxel administration (175 mg/m(2) by a 1 h intravenous infusion) was immediately followed by a 30 min infusion of carboplatin at an area under the concentration time curve (AUC) of 5 on day 1 and etoposide 50 mg orally twice daily (bid) was given on days 2-8. Courses were repeated every 21 days. Patients who had an objective response continued treatment for a maximum of 6 courses. RESULTS: Eighty-four patients were assessable for response. Overall response rate (RR) was 82.1% with 17.8% complete remissions and 64.3% partial remissions. Median survival for LD patients was 20.5 months with a 1 year survival rate of 71.4% and a 3 year survival rate of 21.4%. Median survival of ED I patients was 11 months with a 1 year survival rate of 31.3% and a 3 year survival rate of 3.1%. Overall median survival was 18.1 months with a 1 year survival rate of 56.8% and a 3 year survival rate of 14.8%. Median progression-free intervals were 12.3 months for patients with LD stage of the disease and 8 months with ED I stage. Grade 3/4 toxicity was primarily hematologic. Grade 3/4 leucopenia occurred in 16.0% of courses and febrile episodes were detected in 0.3% of courses. Non-hematologic toxicities were uncommon. Grade 3 GI-tract toxicities or peripheral neuropathy appeared in less than 1% of the courses. Toxicities were detected according to WHO toxicity criteria. CONCLUSION: Paclitaxel can be added at full dose (175 mg/m(2)) to a carboplatin/etoposide combination while maintaining a tolerable toxicity profile. Efficacy data, RR, progression-free interval and survival in both, extensive and limited stage patients compare favorably with other reported data. This new regimen will be further evaluated in comparison to standard regimens in a phase III trial.  相似文献   
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