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931.
PURPOSE: We assess the feasibility of a urinary test for prostate cancer detection in a high-risk patient cohort based on methylation-specific PCR analysis of the pi class glutathione S-transferase (GSTP1) gene promoter. EXPERIMENTAL DESIGN: A total of 45 men underwent transrectal ultrasound-guided biopsy of the prostate for suspected malignancy. Clean-catch voided urine specimens were prospectively collected from each patient immediately after biopsy. Genomic DNA was isolated from urine specimens and subjected to sodium bisulfite modification. Methylation of the GSTP1 promoter was examined in a blinded manner by methylation-specific PCR analysis and correlated with pathology results, and clinical information was obtained from the patient record. RESULTS: Methylation of GSTP1 in the urine was detected in a total of 18 of 36 (50%) informative cases. A total of 7 of 18 (39%) patients with prostate adenocarcinoma identified on their initial biopsy had detectable urinary GSTP1 methylation (58% sensitivity among informative cases). Abnormal urinary GSTP1 methylation was also detected in 7 of 21 (33%) patients without evidence of cancer on biopsy and in 4 of 6 (67%) patients diagnosed with atypia or high-grade prostatic intraepithelial neoplasia. CONCLUSIONS: We have demonstrated the feasibility of a novel, noninvasive molecular approach for the detection of epigenetic changes associated with prostate cancer. A screening test based on GSTP1 methylation in the urine specimens of patients with suspected prostate malignancy may be a useful adjunct to serum screening tests and digital rectal examination findings for identification of men at increased risk of harboring cancer despite a negative biopsy. This molecular assay has potential application for stratification of patients into low- and high-risk groups for surveillance versus repeat biopsy.  相似文献   
932.
PURPOSE: Cyclophosphamide, epirubicin, and fluorouracil (CEF), compared with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy. has lead to an improvement in relapse-free and overall survival in premenopausal women with node-positive breast cancer. We undertook this analysis to more accurately define the estimate of risk of secondary acute leukemia (sAL) following epirubicin-containing chemotherapy regimens. PATIENTS AND METHODS: We assessed the conditional probability of sAL among 1,545 women who received adjuvant (n = 1,477) or neoadjuvant (n = 68) chemotherapy in four National Cancer Institute of Canada Clinical Trials Group trials from 1990 to 1999. The risks associated with epirubicin-containing regimens (CEF or epirubicin and cyclophosphamide [EC]) and other regimens (doxorubicin and cyclophosphamide [AC] or CMF) were determined. RESULTS: A total of 10 cases of sAL were observed (eight acute myelogeneous leukemia, two acute lymphoblastic leukemia): seven among women treated with CEF, two who had received AC, and one following CMF. Using competing risk statistics, the conditional probability of sAL was 1.7% (95% confidence interval [CI], 0.5 to 3.6) among 539 women treated with CEF chemotherapy at a follow-up of 8 years, 0.4% (95% CI, 0% to 1.3%) among the 678 who received CMF, and 1.3% (95% CI, 0% to 4.7%) among the 231 treated with AC. The conditional probability of death from breast cancer at 8 years for the entire group of women treated with epirubicin-containing regimens in all four trials was approximately 34.9%. CONCLUSION: CEF chemotherapy for breast cancer carries a small increased risk of sAL compared with CMF. These estimates of acute leukemia risk are important in discussing treatment with women, especially patients with a lower risk of death from breast cancer, such as those with node-negative breast cancer.  相似文献   
933.
934.
Drug resistance remains a major clinical challenge for cancer treatment. Early studies suggested that overexpression of P-glycoprotein was a major contributor to the chemotherapy resistance of myeloma cells and other tumor cells. Attempts in several clinical studies to reverse multidrug resistance protein (MDR) by using MDR modulators have not yet generated promising results. Recently, the emerging knowledge about the importance of overcoming antiapoptosis and drug resistance in treating a variety of malignancies, including multiple myeloma (MM), raises new hope of improving the treatment outcome for patients with cancer. The therapeutic value of targeting therapies that aim to reverse the antiapoptotic process in MM cells has been explored in a number of experimental systems, and the results have been promising. The proteasome inhibitor PS-341 is a new specifically targeted proapoptotic therapy that has been tested in clinical studies. The results indicate that PS-341 alone is an effective therapy for patients with MM who experience disease relapse. Recent in vitro data also demonstrate that PS-341 can markedly sensitize chemotherapy-resistant MM cells to various chemotherapeutic agents. On the basis of these encouraging results, clinical studies are underway to test the efficacy of PS-341 and chemotherapeutic agents as combination therapy in treating patients with refractory and relapsed MM.  相似文献   
935.
936.
PURPOSE: The purpose of this study was to determine the frequency and overall contribution of specific gene amplification events in the formation of Barrett's adenocarcinomas. The relationship of gene amplification to clinical-pathological variables and its potential usefulness as a marker for early cancer detection were also examined. EXPERIMENTAL DESIGN: We used quantitative PCR and Southern blot analysis to screen 87 cases of Barrett's adenocarcinoma for the presence or absence of 13 distinct gene amplification events. Gene amplification was then examined for correlation with other amplification events and clinical variables (survival, stage, nodal involvement, tumor invasion, smoking history, and gender). Additionally, 22 specimens of Barrett's with high-grade dysplasia (HGD) were examined for the presence of gene amplification. RESULTS: One or more amplification events were present in 50 of 87 (57%) adenocarcinomas. The ERBB2 gene was amplified in 19 of 87 (21.8%), CCNE1 in 11 of 87 (12.6%), GATA4 in 9 of 87 (10.3%), KRAS in 9 of 87 (10.3%), EGFR in 7 of 87 (8.0%), CCND1 in 6 of 87 (6.8%), HNF3alpha in 5 of 87 (5.7%), PIK3CA in 5 of 87 (5.7%), C-MYC in 4 of 87 (4.6%), DYRK2 in 2 of 87 (2.3%), and AIB1, AKT1, and IGF1R were amplified in 0 of 87 (0%) of the tumors. CCND1 amplification was found to correlate negatively with survival (P < 0.05). In addition, the ERBB2 amplicon positively correlated (P < 0.05) with GATA4 amplification. Increased copy number of the ERBB2 (1 of 22), GATA4 (1 of 22), KRAS (2 of 22), C-MYC (1 of 22), CCNE1 (2 of 22), and CCND1 (2 of 22) genes was also observed in one or more Barrett's adenocarcinomas with HGD. CONCLUSIONS: The high frequency of gene amplification in esophageal adenocarcinomas and HGD indicates the important role of these events in esophageal adenocarcinoma development. Additionally, these results underscore the possible usefulness of early detection approaches and chemotherapeutic strategies (ErbB2 and cyclin D1) targeted against amplified gene products.  相似文献   
937.
Despite the unexpected results from the beta-Carotene and Retinol Efficacy Trial (CARET) and similar supplementation trials showing that supplementation with beta-carotene increased, rather than decreased, lung cancer incidence, considerable interest remains in investigating how other compounds in fruits and vegetables may affect lung cancer risk. We used data from 14,120 CARET participants who completed food frequency questionnaires to examine associations of diet with lung cancer risk. After 12 years of follow-up (1989-2001), 742 participants developed lung cancer. We used Cox proportional hazards models to estimate multivariate relative risks (RRs) and 95% confidence intervals (CIs). Analyses were controlled for smoking, asbestos exposure, and other covariates. Analyses of specific botanical groups were also controlled for total fruit and vegetable intake. All models were stratified by CARET treatment arm, and all statistical tests were two-sided. Statistically significant associations of fruit and vegetable intake with lower lung cancer risk were restricted to the CARET placebo arm. The RR for highest versus lowest quintile of total fruit consumption in the placebo arm was 0.56 (95% CI, 0.39-0.81) with a two-sided P for trend = 0.003. Two specific botanical groups were associated with reduced risk of lung cancer. Compared with the lowest quintile of rosaceae fruit consumption, placebo participants in the top quintile had a RR of 0.63 (95% CI, 0.42-0.94; P for trend = 0.02); for cruciferae vegetables, the RR was 0.68 (95% CI, 0.45-1.04; P for trend = 0.01). We did not observe any statistically significant associations of fruit and vegetable intake with lung cancer risk among participants randomized to receive the CARET supplements (30 mg of beta-carotene and 25,000 IU of retinyl palmitate). This report provides evidence that plant foods have an important preventive influence in a population at high risk for lung cancer. However, persons who use beta-carotene supplements do not benefit from the protective compounds in plant foods.  相似文献   
938.
Periventricular leukomalacia (PVL) is a common finding during neurosonography of preterm infants. Secondary thinning of the corpus callosum is seen following PVL, typically from loss of hemispheric white matter tracts. We report a case of direct involvement of the corpus callosum with PVL, its pathogenesis, and its potential as a cause of corpus callosal thinning. Received: 20 September 1996 Accepted: 4 January 1997  相似文献   
939.
Vascular compression of the airway is a significant cause of respiratory compromise in children. While the indications for surgical repair are sometimes life threatening, they can also be subtle. This retrospective study examines 45 surgical cases of tracheobronchial compromise secondary to vascular compression at a large children's hospital between July 1983 and February 1996. A total of 34 were diagnosed with innominate artery compression, ten with a double aortic arch and one with an anomalous right subclavian artery. The 45 patients, 25 male and 20 female, ranged in age from 12 days to 11 years at surgery (average 13 months). A total of 21 (47%) presented with proven or suspected episodes of cyanosis or apnea. All 45 patients had evidence of vascular compression during microlaryngoscopy and bronchoscopy. The diagnosis was confirmed by magnetic resonance imaging (MRI) in 23/45 (51%), barium swallow in 22/45 (49%) and aortogram in 3/45 (7%). There was one death. One patient had a tracheotomy before surgery and continues to require it after surgery. Complete resolution of symptoms was achieved in 39/45 (87%) with five requiring more than one operation before their symptoms resolved completely. A total of four patients experienced a recurrence of symptoms within a variable length of time after surgery. Surgical indications and treatment alternatives will be discussed.  相似文献   
940.
This study reports the preliminary results of an outcomes approach to analysis of the effectiveness of endolymphatic sac decompression (ELSD). Using the medical outcomes survey's 36-item, shortform health survey (SF-36), we assessed the quality of life in 33 patients with disabling Meniere's disease undergoing ELSD for medically intractable vertigo. Results indicate that patients with 1995 American Academy of Otolaryngology-Head and Neck Surgery(AAO/HNS) class A or B outcomes showed no significant difference from population norms on the SF-36, whereas patients with AAO/HNS classes C to E outcomes scored significantly below norms. Six patients who were given the SF-36 preoperatively scored consistently below population norms. Postoperatively, they showed a statistically significant improvement and were statistically equal to norms. These findings suggest that the SF-36 is a good measure of the quality of life impairment in patients with disabling Meniere's disease. In addition, SF-36 scores correlated well with the 1995 AAO/HNS classification.  相似文献   
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