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971.
Immunohistochemical detection of proliferating cell nuclear antigen (PCNA), densitometric analysis of nuclear DNA content and fluorescence in situ hybridization with centromere-specific DNA probes to chromosomes 11 and 17 were carried out on histological sections from 55 colorectal adenomas, in order to identify those adenomas that are more likely to progress to cancer. A considerable variability of PCNA positivity (range: 23-28.2%; mean value: 12.8%), a DNA indexfrom 1 to 2.3 and numerical alterations of chromosome 11 were observed. In particular, 14 out of 55 adenomas (25%), independent of histological type, degree of dysplasia, location and size, showed a DNA-aneuploid content, trisomies and tetrasomies of chromosome 11 and high PCNA index. It was concluded that the combination of some biomarkers (additional chromosomes 11, high PCNA and DNA indices) may allow identification of more aggressive colorectal adenomas with increased ability to undergo malignant transformation.  相似文献   
972.
BACKGROUND: Colorectal carcinoma (CRC) is one of the most common malignancies. In the current work, the role of arginase as a diagnostic marker in patients with recurrent CRC and colorectal liver metastases (CRCLM) was studied. METHODS: Arginase activity was monitored in serum from 40 patients with primary CRC and from 100 patients with CRCLM. Blood was taken before and after patients underwent tumor resection. Studies were conducted for 3 years. RESULTS: Preoperative arginase activity in serum from patients with CRC and CRCLM was much greater compared with the arginase activity in serum from healthy control blood donors. One and two cut-off levels of increased arginase activity were observed in patients with CRC and CRCLM, respectively. After patients underwent tumor resection, the arginase activity decreased to normal values in both patients with CRC and patients with CRCLM. Activity levels remained low in patients who did not develop recurrent CRC or CRCLM (first or second). In patients who developed subsequent recurrences or metastases that appeared after surgery, during 3 years of surveillance, a significant rise in serum arginase activity was observed. The clinical prognosis for patients was worst when the postoperative serum arginase activity was very high, because those patients more often developed second liver metastases or died. CONCLUSIONS: The authors conclude that the determination of serum arginase activity may be a complementary test to confirm the occurrence of CRC and may be useful for the early diagnosis of patients who develop recurrent CRC and/or CRCLM.  相似文献   
973.
BACKGROUND: PINCH is an LIM (double zinc finger domain) protein that functions as an adapter at a key convergence point for integrin and growth factor signal transduction. Because no information is available regarding its expression in vivo in human tissues, this study evaluated the distribution and abundance of PINCH in patients with breast, prostate, lung, colon, and skin carcinomas. METHODS: A polyclonal antibody was raised to a purified 6-histidine PINCH fusion protein and used to evaluate 74 cases comprising 33 breast carcinomas (21 ductal carcinomas, 6 lobular carcinomas, 4 ductal carcinomas in situ, 2 lobular carcinomas in situ), 22 prostate carcinomas, 5 colon carcinomas, 6 lung carcinomas (3 adenocarcinomas and 3 squamous carcinomas), and 8 skin carcinomas (4 basal cell carcinomas and 4 squamous cell carcinomas) by immunoperoxidase histochemistry of formalin-fixed, paraffin-embedded tissues. Lysates of frozen tissue from the epithelium of two normal breasts and six breast carcinomas were evaluated by immunoblotting. RESULTS: Immunostaining for PINCH was increased in the cytoplasm of fibroblastoid cells in areas of the tumor-associated stroma in all carcinomatous tissues evaluated. The most intense stromal immunostaining for PINCH was noted at invasive edges, particularly in breast carcinomatous tissue. Immunoblotting of lysates from normal breast and breast carcinomatous tissue confirmed that PINCH protein expression was markedly increased in breast carcinomatous tissues. CONCLUSIONS: PINCH is up-regulated in tumor-associated stromal cells, particularly at invasive edges, and may be a marker for stroma manifesting the ability to facilitate invasion. Because of this and because PINCH functions as a "molecular switch" in signal transduction, PINCH may be a new target for drug discovery aimed at the tumor-associated stroma.  相似文献   
974.
Although malignant mesothelioma is not a classically immunogenic cancer, there is abundant evidence for immune recognition. The relative ease of obtaining tumor tissue makes mesothelioma ideal for studying surrogate biomarkers such as lymphocytic infiltration or expression of transduced genes. There is evidence that malignant mesothelioma patients as well as asbestos-exposed persons without mesothelioma have impaired immune responsiveness. Substantial progress has been made in animal models using several biological and immunological techniques, but clinical application has been problematic. Systems studied have included lysis by interleukin-2 (IL-2)-activated lymphokine-activated killer (LAK) cells, tumor necrosis factor-alpha (TNF-alpha), a p16-expressing adenovirus vector, suicide gene therapy using the herpes simplex virus-tyrosine kinase (HSV-tk) followed by ganciclovir, and immunomodulatory gene therapy with IL-2, IL-4, interferon-gamma (IFN-gamma), IFN-alpha, TNF-alpha, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6, and IL-1beta transfected into tumors. Vaccinia virus has been studied as a vector for cytokine gene transfer. Suicide gene therapy has been combined with a tumor vaccine. The University of Western Australia is initiating a pilot study of autologous vaccination in malignant mesothelioma. Novel agents under study include the angiogenesis inhibitors SU5416, bevacizumab, and thalidomide. ZD1839, an orally administered, highly selective inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, is being tested in a phase II trial. Since platelet-derived growth factor (PDGF) is thought to be an autocrine growth factor for mesothelioma STI-571 (Gleevec; Novartis, Basel, Switzerland), a highly selective inhibitor of the PDGF receptor tyrosine kinase, is being tested in a phase II trial. The development of more active cytotoxic combinations in this disease should facilitate further studies of chemoimmunotherapy. It seems likely that no single treatment modality will be effective by itself.  相似文献   
975.
To overcome the limitations of standard hollow-fiber module in ensuring efficient cell perfusion and long-term expression of highly differentiated hepatocyte functions, we developed a novel bioreactor in which a three-dimensional hepatocyte culture system was perfused in radial-flow geometry. Isolated porcine hepatocytes were cultured for 2 weeks in recirculating serum-free tissue culture medium, in which NH4Cl and lidocaine were repeatedly added, and ammonia removal, urea synthesis, monoethylglycinexylide (MEGX) production, albumin secretion, Po2, Pco2, O2 consumption, and pH were measured thereafter. During the whole duration of the study, ammonia removal was paralleled by urea production, while MEGX concentration was constantly increased. Our results indicated that hepatocytes remained differentiated and metabolically active throughout the duration of the study. The radial-flow bioreactor allowed physiological contact between recirculating fluid and cells by equalizing the concentration of the perfusing components, including O2, throughout the module, suggesting a potential use of this configuration for extracorporeal liver support.  相似文献   
976.
Aim of the paper is to evaluate 43 extrapleural pneumonectomy performed from 1988 to May 2000. Criteria for extrapleural pneumonectomy were pleural biopsy by thoracoscopy, potentially completely resectable unilateral disease by computed tomography and predicted postresection forced expiratory volume >1,3 L/sec. The resections regarded 33 pleural mesothelioma, 9 pleural lung-carcinosis and 1 pleural melanoma effusion. The perioperative mortality rate was 2,2% (1 death) and morbidity 21,4%.  相似文献   
977.
PURPOSE: We evaluate voiding cystourethrography as a method for identifying bladder instability in infants. MATERIALS AND METHODS: Cystometry was combined with voiding cystourethrography in 79 male and 64 female infants with first time urinary tract infection. Bladder wall irregularity, elongation of bladder shape, and filling of the posterior urethra were transient radiological signs occurring during bladder filling and were considered to reflect bladder instability. A pediatric radiologist looked for these signs on all 480 films exposed during bladder filling. The results were correlated to simultaneous detrusor pressure recordings. The analysis was repeated independently by a urologist to evaluate the reliability of the radiological signs used. RESULTS: The sensitivity and specificity were both 90% in the evaluation of radiological signs of bladder instability. Filling of the posterior urethra was the least frequently reported radiological sign, which was seen at 53% of unstable contractions. However, when this sign was reported, instability was usually correctly detected (85%). Evaluation accuracy had improved with increasing numbers of noted signs per film. This accuracy had included 29%, 67% and 91% of unstable contractions that were correctly diagnosed when 1, 2 or 3 signs were noted, respectively. The number of noted signs was positively related to the strength of the unstable detrusor contraction. Urologist evaluations had similar results to the radiologist, although the sensitivity was somewhat lower (79% and 90%, respectively). CONCLUSIONS: Unstable detrusor contractions could be identified in infants by evaluation of radiological signs on voiding cystourethrography. Findings of bladder wall irregularity, elongation of bladder shape and filling of the posterior urethra indicated unstable detrusor contraction. The more such findings are observed, the stronger the indication.  相似文献   
978.
Context  Herpes simplex virus type 2 (HSV-2) is one of the most common sexually transmitted infections in the United States. No prospective study has shown the ability of condoms to reduce transmission of HSV-2. Objective  To evaluate risk factors for HSV-2 acquisition and efficacy of condoms in prevention of HSV-2 transmission. Design  Analysis of data from a randomized, double-blind, placebo-controlled trial conducted December 13, 1993, to June 28, 1996, of an ineffective candidate HSV-2 vaccine with 18 months of follow-up. Setting  Eighteen clinical trial centers in the United States. Participants  A total of 528 monogamous couples discordant for HSV-2 infection, including an HSV-2–susceptible population of 261 men and 267 women. Main Outcome Measure  Acquisition of HSV-2 infection by susceptible partners, compared with those remaining free of HSV-2 with regard to demographic characteristics, sexual activity, and condom use. Results  Twenty-six women (9.7%) vs 5 men (1.9%) acquired HSV-2, for a rate per 10 000 sex acts (episodes of sexual intercourse) of 8.9 vs 1.5, respectively (P<.001). In multivariable analysis, younger age (adjusted hazard ratio [HR] per 5 years, 1.57; 95% confidence interval [CI], 1.22-2.04), seropositivity for HSV-1 and HSV-2 vs HSV-2 alone in the source partner (adjusted HR, 2.34; 95% CI, 1.14-4.82), and more frequent sexual activity (adjusted HR per additional sex act per week, 1.10; 95% CI, 1.01-1.19) were associated with higher risk of HSV-2 acquisition. Condom use during more than 25% of sex acts was associated with protection against HSV-2 acquisition for women (adjusted HR, 0.085; 95% CI, 0.01-0.67) but not for men (adjusted HR, 2.02; 95% CI, 0.32-12.50). Risk of HSV-2 transmission declined from 8.5 per 100 person-years in the initial 150-day interval to 0.9 per 100 person-years in the final 150-day interval (P = .002 for trend), concurrent with a decrease in sexual activity and proportion of sex acts occurring when the source partner had genital lesions. Conclusions  Condom use offers significant protection against HSV-2 infection in susceptible women. Changes in sexual behavior, correlated with counseling about avoiding sex when a partner has lesions, were associated with reduction in HSV-2 acquisition over time. These data suggest that identification of discordant couples can reduce transmission of HSV-2, especially for heterosexual couples in which the male partner has HSV-2 infection.   相似文献   
979.
OBJECTIVE: To determine the relationship between p53 overexpression and vascular endothelial growth factor (VEGF) upregulation in liver and abdominal metastases from colon cancer. The analysis in the two metastatic sites was carried out to evaluate the potential role of microenvironment in the molecular regulation of VEGF. METHODS: Bioptic specimens of liver and abdominal metastases from colon carcinomas were examined by immunohistochemistry for p53 and VEGF expressions. Consecutive cases with assessable tumor tissue were selected. RESULTS: The study population consisted of 24 cases having liver metastases and 34 cases having abdominal metastases. Abdominal metastases showed a higher number of VEGF-positive cases and a higher intensity of VEGF immunoreactivity than liver metastases did (p = 0.01). The combined analysis of p53 and VEGF showed a strong association between the two markers in the 24 liver metastases; 9 cases were VEGF positive/p53 positive and 15 cases were VEGF negative/p53 negative. This relationship was not found in the 34 abdominal metastases, which showed concordance between the two markers in 9 VEGF-positive/p53-positive cases only. CONCLUSIONS: Microenvironment factors like hypoxia may have a predominant role in inducing VEGF expression and they can override the molecular control of p53 on VEGF.  相似文献   
980.
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