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61.
PURPOSE: Our goal was to examine a panel of 11 biochemical variables, measured in cytosolic extracts of ovarian tissues (normal, benign, and malignant) by quantitative ELISAs for their ability to diagnose, prognose, and predict response to chemotherapy of ovarian cancer patients. EXPERIMENTAL DESIGN: Eleven proteins were measured (9 kallikreins, B7-H4, and CA125) in cytosolic extracts of 259 ovarian tumor tissues, 50 tissues from benign conditions, 35 normal tissues, and 44 tissues from nonovarian tumors that metastasized to the ovary. Odds ratios and hazard ratios and their 95% confidence interval were calculated. Time-dependent receiver operating characteristic curves for censored survival data were used to evaluate the performance of the biomarkers. Resampling was used to validate the performance. RESULTS: Most biomarkers effectively separated cancer from noncancer groups. A composite marker provided an area under the curve of 0.97 (95% confidence interval, 0.95-0.99) for discriminating normal and cancer groups. Univariately, hK5 and hK6 were positively associated with progression. After adjusting for clinical variables in multivariate analysis, both hK10 and hK11 significantly predicted time to progression. Increasing levels of hK13 were associated with chemotherapy response, and the predictive power of hK13 to chemotherapy response was improved by a panel of five biomarkers. CONCLUSIONS: The evidence shows that a group of kallikreins and multiparametric combinations with other biomarkers and clinical variables can significantly assist with ovarian cancer classification, prognosis, and response to platinum-based chemotherapy. In particular, we developed a multiparametric strategy for predicting ovarian cancer response to chemotherapy, comprising several biomarkers and clinical features.  相似文献   
62.
A 45-year-old man presented with clinical manifestations of foveomacular retinitis, including visual symptoms and foveal lesions characteristic of solar retinopathy, but repeated questions failed to elicit a history of sun gazing. Cross-sectional retinal images produced by optical coherence tomography revealed localized loss of retinal pigment epithelium cells in both eyes. A different pattern of reflectivity at the level of the photoreceptor layer was observed between the right and left eye, reflecting asymmetry in tissue damage. This case is described to provide additional evidence that solar retinopathy and foveomacular retinitis are the same entity and may also have common optical coherence tomography findings.  相似文献   
63.
Prostate specific antigen (PSA) is a tumor marker used widely for the diagnosis and monitoring of prostatic adenocarcinoma. Recently, we provided evidence that PSA may also be produced by breast tumors. In this report we examined quantitatively the PSA levels in 199 breast tumors, 48 tissues with benign breast disease (BBD, 34 fibroadenomas), and 36 normal breast tissues. Significant amounts of PSA (≥ 0.030 ng of PSA per mg of total protein) were found in 28% of breast tumors, 65% of BBD tissues, and 33% of normal breast tissues. PSA positivity in breast tumors was highest in stage I disease (34%) and decreased with disease stage (24% in stage II and 18% in stage III–IV). Using polymerase chain reaction amplification we have shown PSA mRNA presence in patients with PSA protein-positive tissues (benign and malignant) but not in patients with PSA protein-negative tissues. Our data suggest that PSA is expressed frequently by normal breast tissue, by tissue of benign breast diseases, and by breast cancer tissue. Highest expression is seen in benign breast disease and lowest expression in advanced stage cancerous tissue. As PSA production is mediated by steroid hormones and their receptors, we propose that PSA may be a new marker of steroid hormone action in the normal or diseased female breast. The role of this enzyme in the development of breast diseases including breast cancer is currently unknown.  相似文献   
64.
65.
Biologically and clinically meaningful tumor classification schemes have long been sought. Some malignant epithelial neoplasms, such as those in the thyroid and endometrium, exhibit more than one pattern of differentiation, each associated with distinctive clinical features and treatments. In other tissues, all carcinomas, regardless of morphological type, are treated as though they represent a single disease. To better understand the biological and clinical features seen in the four major histological types of ovarian carcinoma (OvCa), we analyzed gene expression in 113 ovarian epithelial tumors using oligonucleotide microarrays. Global views of the variation in gene expression were obtained using PCA. These analyses show that mucinous and clear cell OvCas can be readily distinguished from serous OvCas based on their gene expression profiles, regardless of tumor stage and grade. In contrast, endometrioid adenocarcinomas show significant overlap with other histological types. Although high-stage/grade tumors are generally separable from low-stage/grade tumors, clear cell OvCa has a molecular signature that distinguishes it from other poor-prognosis OvCas. Indeed, 73 genes, expressed 2- to 29-fold higher in clear cell OvCas compared with each of the other OvCa types, were identified. Collectively, the data indicate that gene expression patterns in ovarian adenocarcinomas reflect both morphological features and biological behavior. Moreover, these studies provide a foundation for the development of new type-specific diagnostic strategies and treatments for ovarian cancer.  相似文献   
66.
67.
PURPOSE: Current serum testing for the detection of prostate cancer (PCa) lacks specificity. On diagnosis, the optimal therapeutic pathway is not clear and tools for adequate risk assessment of localized PCa progression are not available. This leads to a significant number of men having unnecessary diagnostic biopsies and surgery. A search for novel tumor markers identified macrophage inhibitory cytokine 1 (MIC-1) as a potentially useful marker. Follow-up studies revealed MIC-1 overexpression in local and metastatic PCa whereas peritumoral interstitial staining for MIC-1 identified lower-grade tumors destined for recurrence. Consequently, we sought to assess serum MIC-1 measurement as a diagnostic tool. EXPERIMENTAL DESIGN: Using immunoassay determination of serum MIC-1 concentration in 1,000 men, 538 of whom had PCa, we defined the relationship of MIC-1 to disease variables. A diagnostic algorithm (MIC-PSA score) based on serum levels of MIC-1, total serum prostate-specific antigen, and percentage of free prostate-specific antigen was developed. RESULTS: Serum MIC-1 was found to be an independent predictor of the presence of PCa and tumors with a Gleason sum > or =7. We validated the MIC-PSA score in a separate population and showed an improved specificity for diagnostic blood testing for PCa over percentage of free prostate-specific antigen, potentially reducing unnecessary biopsies by 27%. CONCLUSIONS: Serum MIC-1 is an independent marker of the presence of PCa and tumors with a Gleason sum of > or =7. The use of serum MIC-1 significantly increases diagnostic specificity and may be a future tool in the management of PCa.  相似文献   
68.
OBJECTIVE: To conduct an evidence-based technology assessment to determine whether the routine use of anastrozole or any of the aromatase inhibitors in the adjuvant breast cancer setting is appropriate for broad-based conventional use in clinical practice. POTENTIAL INTERVENTIONS: Anastrozole, letrozole, and exemestane. OUTCOMES: Outcomes of interest include breast cancer incidence, breast cancer-specific survival, overall survival, and net health benefit. EVIDENCE: A comprehensive, formal literature review was conducted for relevant topics and is detailed in the text. Testimony was collected from invited experts and interested parties. The American Society of Clinical Oncology (ASCO)-prescribed technology assessment procedure was followed. BENEFITS/HARMS: The ASCO panel recognizes that a woman and her physician's decision regarding adjuvant hormonal therapy is complex and will depend on the importance and weight attributed to information regarding both cancer and non-cancer-related risks and benefits. CONCLUSION: The panel was influenced by the compelling, extensive, and long-term data available on tamoxifen. Overall, the panel considers the results of the Arimidex (anastrozole) or Tamoxifen Alone or in Combination (ATAC) trial and the extensive supporting data to be very promising but insufficient to change the standard practice at this time (May 2002). A 5-year course of adjuvant tamoxifen remains the standard therapy for women with hormone receptor-positive breast cancer. The panel recommends that physicians discuss the available information with patients, and, in making a decision, acknowledge that treatment approaches can change over time. Individual health care providers and their patients will need to come to their own conclusions, with careful consideration of all of the available data. (Specific questions addressed by the panel are summarized in Appendix 3.) VALIDATION: The conclusions of the panel were endorsed by the ASCO Health Services Research Committee and the ASCO Board of Directors.  相似文献   
69.
Although prostate-specific antigen (PSA) is the most valuable tumor marker for the diagnosis and management of prostate carcinoma, it is widely accepted that PSA is not prostate specific. Numerous studies have shown that PSA is present in some female hormonally regulated tissues, principally the breast and its secretions. In this review, we summarize the findings of PSA in the breast, and focus on its potential for clinical applications in breast disease. PSA is produced by the majority of breast tumors and is a favorable indicator of prognosis in breast cancer. Low levels of PSA are released into the female circulation, and while the level of serum PSA is elevated in both benign and malignant breast disease, the molecular form of circulating PSA differs between women with and without breast cancer. These findings indicate that PSA may have potential diagnostic utility in breast cancer. PSA may also have a clinical application in benign breast disease, as both the level and molecular form of PSA differ between Type I and II breast cysts. High levels of PSA have been reported in nipple aspirate fluid (NAF) and recent studies have shown that the concentration of PSA in NAF is inversely related to breast cancer risk, indicating that NAF PSA may represent a clinical tool for breast cancer risk assessment. Thus, PSA represents a marker with numerous potential clinical applications as a diagnostic and/or prognostic tool in breast disease.  相似文献   
70.
Steroid hormone activity of flavonoids and related compounds   总被引:12,自引:0,他引:12  
Soy isoflavones have been studied extensively for estrogenic and antiestrogenic properties. Other flavonoids, found in fruits, vegetables, tea and wine, have been much less tested for steroid hormone activity. We therefore assessed the estrogenic, androgenic and progestational activities of 72 flavonoids and structurally-related compounds. These compounds were tested on BT-474 human breast cancer cells at concentrations of 108–10–5M, with estradiol (estrogen), norgestrel (progestin) and dihydrotestosterone (androgen) used as positive controls, and ethanol (solvent) as a negative control. pS2, an estrogen-regulated protein, and prostate-specific antigen (PSA), regulated by androgens and progestins, were quantified in tissue culture supernatants using ELISA-type immunofluorometric assays developed in-house. Of the 72 compounds tested, 18 showed estrogenic activity at 10–5M. Of this subset, seven also showed progestational activity at this concentration. The soy isoflavones, biochanin A and genistein, showed the most potent estrogenic activity, with a dose-response effect up to 10–7 M. Of all other flavonoids, luteolin and naringenin displayed the strongest estrogenicity, while apigenin had a relatively strong progestational activity. Based on our data, we have formulated a set of structure/function relationships between the tested compounds. Flavonoids, therefore, exhibit significant steroid hormone activity, and may have an effect in the modification of cancer risk by diet, or in cancer therapeutics and prevention.  相似文献   
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