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201.
Non-Hodgkin's lymphoma of the central nervous system (NHL-CNS) is thought to account for about 1 % of primary brain tumours. Radiation therapy has mainly been applied to treat cerebral lymphoma, but the low cure rate and the lack of enduring response have stimulated the search for alternatives. With the aim of postponing radiotherapy as long as possible, we tested the efficacy of a M-BACOD schedule administered immediately after histological diagnosis in 14 patients. After two M-BACOD courses 10 (71%) patients displayed an objective response (i.e. were apparently tumour-free when examined by CT). In 6 (60%) M-BACOD-responsive patients, radiotherapy was delayed for 5 months (without recurrences after a follow-up ranging from 9 to 18 months). Moreover, in 3 M-BACOD-responsive patients, no recurrence took place (even without radiotherapy) after a follow-up of 6–12 months. We conclude that radiation can be postponed after chemotherapy or delayed until tumor recurrence.This paper was presented at the 3rd Meeting of the European Neurological Society, Lausanne, 27 June–1 July, 1992  相似文献   
202.
A new method for intraperitoneal tumour targetting in ovarian cancer using biotinylated monoclonal antibodies (MoAb) and radioactive streptavidin is described. Fifteen patients with histologically documented ovarian carcinoma were injected intraperitoneally with 2 mg of biotinylated MoAb MOv18, followed 3–5 days later by 100–150 g of indium-111 streptavidin, at the specific activity of 280–370 MBq/mg in 500 ml of normal saline. No toxicity was observed. Tumours were imaged from 2 to 48 h after radioactivity injection by recording both planar and single photon emission tomography (SPET) data. All patients underwent surgery 1–8 days later (mean 3 days) after scanning. The resected tumour and normal tissue radioactivity were measured. On the day of surgery, the tumour to normal tissue ratio was 9:1 (range 3:1–30:1) and 45:1 (range 12:1–120:1) for intra- and extraperitoneal samples, respectively. The mean tumor to blood ratio was 14:1 (range 4:1–30:1). The injected dose (i.d.) per gram of tumour was 0.112 (range 0.01–0.3) for recurrences and 0.05 for primary tumour (range 0.005–0.2). Over 24–48 h 14% i.d. (range 8–18% i.d.) was found in the urine, 14% i.d. (range 629% i.d.) in the blood and 63% i.d. (range 56–70% i.d.) was still in the peritoneal cavity. These preliminary clinical data suggest that this two-step strategy may be superior to the conventional approach (radiolabelled antibodies) for intraperitoneal radioimmunolocalization and radioimmunotherapy of ovarian cancer. Offprint requests to: G. Paganelli  相似文献   
203.
Summary Ipriflavone, a synthetic isoflavone-derived flavonoid, was shown to have inhibitory effect on bone resorption. In order to study its mechanism of action directly on bone, 46 female Wistar rats were divided into six groups and medicated orally for 25 days as follows: groups 1 and 2 were given 1% carboxymethylcellulose solution (vehicle), groups 3, 4, 5, and 6 were administered ipriflavone at doses of 0.178, 0.356, 0.712, and 1.424 mmol/kg/day (suspended in vehicle), respectively. On the 22nd day, parathyroid glands, taken from donor rats, were transplanted in contact with the outer surface of the periosteum of both the right and the left parietal bones of rats from groups 2, 3, 4, 5, and 6. The group 1 rats underwent sham operation. Bone histomorphometry, performed on the ectocranial periosteum of parietal bones, showed that absolute erosion boundary, absolute eroded area, absolute erosion depth, number of tartrate-resistant acid phosphatase (TRAP)-positive polinucleated osteoclasts, and number of TRAP-positive mononucleated cells decreased in ipriflavone-treated rats compared with group 2 rats. The reduction was roughly proportional to the increase of drug dosage and reached statistical significance in rats of groups 5 and 6. The same parameters were extremely low in group 1 rats. Mineral apposition rate did not differ in any of the groups. Significant increase of serum calcium and significant decrease of serum phosphate were found in group 2 rats compared with group 1 rats, whereas no differences from controls were detected in ipriflavone-treated animals.The results demonstrate that ipriflavone has a direct inhibitory effect upon bone resorption, probably by reducing recruitment or differentiation of osteoclasts, rather than by inhibiting the resorption activity of differentiated osteoclasts. Ipriflavone also seems to exert a protective action against parathyroid hormone (PTH) diffusion from the site of parathyroid gland transplantation.  相似文献   
204.
Over a 2-year period 192 patients with acute myocardial infarction (AMI) were transported by helicopter and treated with recombinant tissue-plasminogen activator (tPA). All patients were entered into the Thrombolysis in Myocardial Infarction-Phase II (TIMI II) trial. Eighty-two of these patients were treated with tPA after aeromedical transport to a tertiary care center. One hundred ten patients had tPA treatment initiated by the flight crew prior to transport. The flight crews initiated therapy 28 +/- 11 minutes after arrival at the sending hospital. The post-flight treated patients received the tPA bolus 82 +/- 20 minutes after arrival at the sending hospital (P less than .0001), and 41 +/- 18 minutes after arrival at the receiving hospital (P less than .0001). Based on enzyme and electrocardiographic changes, all patients in the study had a confirmed diagnosis of AMI before discharge. Patients with inferior myocardial infarction (MI) treated with tPA in-flight were more likely to suffer from bradycardia and hypotension requiring atropine injection during transport than the post-flight treated patients or in-flight treated patients with anterior MI. There was no in-flight mortality in either group. Our experience indicates that patients with AMI can be transported safely during tPA therapy. Also, a trained team whose sole responsibility is the early evaluation and initiation of therapy in a patient with AMI can function as accurately and significantly more rapidly than tertiary care emergency department and ICU personnel following identical protocols.  相似文献   
205.
206.
Controversy still exists about the optimal lymph node (LN) dissection for potentially curable gastric cancer. For rational LN dissection it is important to know the incidence of metastasis at each LN station. For this purpose a computer program was developed using data from 4302 primary gastric cancers treated at the National Cancer Center Hospital in Tokyo between 1969 and 1989. To evaluate the accuracy of the computer program, the differences between the individual reports generated by the computer and the stored data were investigated in 282 Italian patients submitted to curative gastrectomy and D2 or more extended LN dissections for gastric cancer. Receiver operating characteristic (ROC) analysis was used to assess the sensitivity and specificity of the program for predicting LN metastases in each of the 16 regional LN stations. The computer program showed good predictive ability for LN metastases in most of the 16 LN stations, as the areas under the curve ranged from 0.741 (station 15) to 0.944 (station 8), with a mean of 0.856. A critical cutoff point of 18% of the program's expected percentage was the value maximizing the validity of the prediction. Using an “absolute” cutoff point of 0%, the overall rate of false-negative (FN) predictions in 176 N+ patients was 11.9%; of these, 11 (6.2%) were absolute FNs, in which the program totally failed to estimate LN metastases; the remaining 10 cases (5.7%) were relative FNs because the specific prediction was positive for a different depth of stomach invasion. The low number of D3/D4 lymphadenectomies in the historical database may affect the low estimate of metastases to N3/N4 nodes generated by the program. Based on these data, the program predicts with good accuracy the extent of LN metastases from gastric cancer, but it is not recommended for directing the surgeon to perform more extensive lymphadenectomy.  相似文献   
207.
Here, we summarize recent data pertaining to the effects of GABAA receptor modulators on the receptor gene expression in order to elucidate the molecular mechanisms behind tolerance and dependence induced by these drugs. Drug selectivity and intrinsic activity seems to be important to evidence at the molecular level the GABAA receptor tolerance. On the contrary, we suggested that all drug tested are equally potentially prone to induce dependence. Our results demonstrate that long-lasting exposure of GABAA receptors to endogenous steroids, benzodiazepines and ethanol, as well as their withdrawal, induce marked effects on receptor structure and function. These results suggest the possible synergic action between endogenous steroids and these drugs in modulating the functional activity of specific neuronal populations. We report here that endogenous steroids may play a crucial role in the action of ethanol on dopaminergic neurons.  相似文献   
208.
Soluble CD40 ligand plasma levels in lung cancer.   总被引:7,自引:0,他引:7  
PURPOSE: Tumor-induced platelet activation may cause the release of various cytokines, including CD40 ligand (CD40L). Activation of the CD40/CD40L pathway in human tumors may result in thrombin generation, which is known to be involved in angiogenesis. Thus, we investigated whether soluble (s)CD40L levels are increased in patients with lung cancer as a result of platelet and/or coagulation activation. EXPERIMENTAL DESIGN: Citrated plasma samples were obtained from 120 patients with different stages and histotypes of lung cancer and 60 age- and sex-matched control subjects. sCD40L, sP-selectin (marker of platelet activation), prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels (both markers of coagulative activation) were measured in all samples. RESULTS: Patients with lung cancer had median sCD40L levels higher than in control subjects (0.46 versus 0.13 ng/ml; P < 0.0001), although correlation with the stage of disease was not evident. Nonetheless, sCD40L levels were significantly higher in squamous cancer compared with adenocarcinoma (0.75 versus 0.27 ng/ml; P < 0.05). Moreover, median sCD40L levels were higher in stage IV compared with nonmetastatic squamous lung cancer (1.02 versus 0.61 ng/ml; P < 0.05). sCD40L levels significantly correlated with sP-selectin (P < 0.001), prothrombin fragment 1 + 2 (P < 0.001), or thrombin-antithrombin III complex (P < 0.05) in squamous lung cancer, but only sP-selectin (P = 0.011) was independently related to sCD40L. CONCLUSIONS: These findings indicate that elevated sCD40L levels can be preferentially found in patients with advanced squamous cancer and provide evidence that increased levels of this cytokine are associated to the occurrence of in vivo platelet activation.  相似文献   
209.
PURPOSE: The aim of the study was to evaluate the activity of epidoxorubicin (EPI) and gemcitabine (GEM) and to define the most effective schedule in human bladder cancer cells. EXPERIMENTAL DESIGN: The study was performed on HT1376 and MCR cell lines. Cells were exposed for 1 and 24 h to drugs used in different schemes. Cytotoxic activity was evaluated by the sulforhodamine B assay, potential clinical activity was estimated by relative antitumor activity, and the type of drug interaction was assessed using the method of Chou and Talalay. Cell cycle perturbations and apoptosis were assessed by flow cytometry; BAX, BCL-2, and P53 expression was evaluated by Western blot; and DNA damage was assessed using the alkaline Comet assay. RESULTS: EPI and GEM produced a cytotoxic effect in both cell lines, with 50% inhibitory concentration and relative antitumor activity values suggestive of a high clinical activity. Simultaneous treatment with EPI and GEM and the sequence GEM-->EPI caused an antagonistic interaction (combination index > 1) after both 1- and 24-h treatments. Conversely, the inverse sequence, EPI-->GEM, produced a synergistic interaction that was more pronounced in MCR cells than in HT1376 cells. The increase in DNA-damaged cells from 10% to 20% after single-drug exposure to 40-60% at the end of EPI-->GEM treatment may explain the synergistic interaction produced by the anthracycline-antimetabolite sequence. CONCLUSIONS: Our findings show that the efficacy of the EPI and GEM combination is highly schedule dependent and indicate that the most active scheme is EPI followed by GEM, which is currently being validated in an ongoing intravesical Phase I-II clinical protocol.  相似文献   
210.
PURPOSE: Recent studies sought to refine lung cancer classification using gene expression microarrays. We evaluate the extent to which these studies agree and whether results can be integrated. EXPERIMENTAL DESIGN: We developed a practical analysis plan for cross-study comparison, validation, and integration of cancer molecular classification studies using public data. We evaluated genes for cross-platform consistency of expression patterns, using integrative correlations, which quantify cross-study reproducibility without relying on direct assimilation of expression measurements across platforms. We then compared associations of gene expression levels to differential diagnosis of squamous cell carcinoma versus adenocarcinoma via reproducibility of the gene-specific t statistics and to survival via reproducibility of Cox coefficients. RESULTS: Integrative correlation analysis revealed a large proportion of genes in which the patterns agreed across studies more than would be expected by chance. Correlation of t statistics for diagnosis of squamous cell carcinoma versus adenocarcinoma is high (0.85) and increases (0.925) when using only the most consistent genes identified by integrative correlation. Correlations of Cox coefficients ranged from 0.13 to 0.31 (0.33-0.49 with genes selected for consistency). Although we find genes that are significant in multiple studies but show discordant effects, their number is approximately that expected by chance. We report genes that are reproducible by integrative analysis, significant in all studies, and concordant in effect. CONCLUSIONS: Cross-study comparison revealed significant, albeit incomplete, agreement of gene expression patterns related to lung cancer biology and identified genes that reproducibly predict outcomes. This analysis approach is broadly applicable to cross-study comparisons of gene expression profiling projects.  相似文献   
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