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981.
OBJECTIVES: We examined the association between attributes of primary care providers and care for depression, from a patients' perspective, among a sample of predominantly low-income African American women. METHODS: Computer-assisted telephone interviews were conducted among a population-based sample of 1202 women residing in Washington, DC. RESULTS: Respondents whose primary care physicians provided more comprehensive medical services were more likely to be asked about and treated for depressive symptoms than women whose providers were less medically comprehensive. Women who rated their providers as having more respect for them also were more likely to be asked about and treated for depression. CONCLUSIONS: More comprehensive primary care delivery and a physician-patient relationship focused on mutual respect are associated with greater rates of physician inquiry about and treatment for depression among vulnerable women.  相似文献   
982.
On the basis of our previous clinical experience, we hypothesized in this study that the duration and/or quality of labor analgesia produced by intrathecal sufentanil was less in cocaine-abusing parturients compared with nonabusing parturients. Ten micro g of sufentanil was given intrathecally as part of a combined spinal-epidural (CSE) technique to two groups of laboring parturients: 1). those whose urine tested positive for cocaine (cocaine group), and 2). those whose urine tested negative for cocaine (control group). The epidural catheter was not injected with local anesthetic until the patient requested additional pain relief. The time from injection of intrathecal sufentanil until patient request for additional pain relief was defined as duration of analgesia. Baseline visual analog pain score (VAPS) and cervical dilation were measured before the CSE was performed. After injection of intrathecal sufentanil, VAPS was recorded at specific intervals. Cervical dilation was again documented when the patient requested additional analgesia. We found that both groups reported high baseline VAPS and a marked decrease in VAPS after injection of sufentanil that did not differ between groups. Geometric mean duration of pain relief with adjustment for cervical dilation was 87 min in the cocaine group compared with 139 min in the control group (P = 0.019). All patients experienced itching. We conclude that intrathecal sufentanil produces a similar quality but shorter duration of analgesia in cocaine-abusing parturients compared with nonabusing parturients. IMPLICATIONS: Intrathecal sufentanil administered as part of a combined spinal-epidural technique produces similar quality but reduced duration of labor analgesia in cocaine-abusing parturients compared with nonabusing parturients.  相似文献   
983.
Posttraumatic stress disorder (PTSD) commonly occurs in conjunction with other psychiatric disorders. The present article reviews PTSD and its comorbidities such as anxiety disorders, substance abuse, mood disorders, suicide attempts, dissociative disorder and somatoform disorder.  相似文献   
984.
The aim of this prospective study was to evaluate anatomical-functional image fusion using the new technology of combined transmission and emission tomography (SPET/CT) in patients with neuroendocrine tumours (NET). Fifty-four patients with known or suspected NET prospectively underwent both tumour scintigraphy with (111)In-octreotide (n=43) or (123)I-MIBG (n=11) and contrast-enhanced high-end spiral CT. Scintigraphy was performed using a gamma camera (Millennium VG & Hawkeye, GE) with an integrated X-ray tube for combined transmission and emission tomography. SPET and high-end CT were interpreted blinded with regard to localisation and classification of lesions. Analysis of fused images (SPET/CT) was done on a lesion-by-lesion basis, followed by re-evaluation of SPET and high-end CT by consensus. The standard of reference for confirming the presence or absence of malignancy was either histopathology or clinical and imaging follow-up data. A total of 120 lesions were identified by CT and/or scintigraphy. This group included four patients with negative SPET but eight liver lesions on CT that were proven to be metastases. We excluded from the analysis two patients with no evidence of tumour on either modality, two lesions that lacked comparison with the standard of reference and two patients, each with two lesions, who were lost to follow-up. In 56 of the 114 evaluated lesions (49%), the results of SPET and CT were concordant; all lesions were interpreted as malignant. In 58 of 114 lesions (51%), consensus reading of fused images changed the image interpretation of 39 CT scans and 19 SPET studies: 31 lesions previously interpreted as equivocal (n=10) or benign (n=21) were re-classified as malignant and 27 lesions previously interpreted as equivocal (n=19) or malignant (n=8) were re-evaluated as benign. The highest accuracy (99%) in classifying NET lesions was achieved by combined analysis of SPET/CT ("hawkeye") and high-end CT. The specificity of SPET/CT was significantly higher than that of CT alone (P=0.0026) and slightly higher than that of SPET alone, but the accuracy of SPET/CT was inferior to that of side-by-side analysis of SPET and high-end CT (P=0.013) or visual correlation of SPET/CT and high-end CT (P<0.0001). Therapy was changed in 14 of 50 patients (28%) owing to the results of image fusion: in five patients tumour could be excluded, three patients were spared unnecessary surgery because of additional lesions indicating systemic tumour spread, in four patients the surgical approach was changed owing to precise tumour localisation and minimising of the surgical field, and in two patients medical and radiopeptide therapy was changed. Anatomical-functional image fusion allows for improved localisation and characterisation of NET with resultant alteration of the treatment approach in a substantial proportion of patients.  相似文献   
985.
Exchange of catenins in cadherin-catenin complex   总被引:2,自引:0,他引:2  
beta-Catenin is an intracellular multifunctional protein. In complex with the transmembrane adhesive receptor E-cadherin, it becomes plasma membrane-associated and mediates intercellular adhesion. A cytosolic pool of beta-catenin interacts with DNA-binding proteins and participates in signal transduction. To reveal the possible cross-talk between these two pools, we studied whether beta-catenin is exchanged between its free and cadherin-bound states. We found that pulse-labeled beta-catenin replaces the beta-catenin bound to the cell surface prebiotinylated E-cadherin immediately after synthesis. Approximately 25% of all pulse-labeled beta-catenin destined for E-cadherin associates with this protein via this mechanism. The rest of the newly synthesized beta-catenin arrives at the plasma membrane in a complex with the E-cadherin precursor. Immediately after arrival, this beta-catenin pool is transferred to the prebiotinylated E-cadherin. beta-Catenin released from E-cadherin may participate in new exchange cycles. This beta-catenin exchange is strongly affected in cells that contain mutations in the tumor suppressor gene APC. This process may contribute significantly to both cell-cell adhesion and beta-catenin-dependent signaling.  相似文献   
986.
Dendritic cell (DC)-based vaccines have exhibited minimal effectiveness in treating established tumors, likely because of factors present in the tumor microenvironment. One such factor is transforming growth factor beta (TGF-beta), a cytokine that is produced by numerous tumor types and has been demonstrated to impair DC functions in vitro. We have evaluated the effect of TGF-beta on the immunostimulatory activities of DCs. We demonstrate that TGF-beta exposure inhibits the ability of DCs to present antigen, stimulate tumor-sensitized T lymphocytes, and migrate to draining lymph nodes. Neutralization of TGF-beta using the TGF-beta-neutralizing monoclonal antibody 2G7 enhanced the ability of DC vaccines to inhibit the growth of established 4T1 murine mammary tumors. Treatment of 4T1 tumors transduced with the antisense TGF-beta transgene (4T1-asT) with the combination of DC and 2G7 monoclonal antibody inhibited tumor growth and resulted in complete regression of tumors in 40% of the mice. These results demonstrate that neutralization of TGF-beta in tumor-bearing mice enhances the efficacy of DC-based vaccines.  相似文献   
987.
Contributions of ATM mutations to familial breast and ovarian cancer   总被引:11,自引:0,他引:11  
This study addresses the prevalence of ATM mutations and the association with breast cancer in Austrian families selected for a history of breast or ovarian cancer or both [hereditary breast and ovarian cancer (HBOC)]. In 270 HBOC families previously screened for BRCA1 and BRCA2 mutations, 137 different sequence alterations of ATM were identified. Seven of these were mutations presumed to cause ataxia telangiectasia based on their effect on the ATM protein, including five that caused a protein truncation and two missense mutations in the catalytic kinase domain of the highly conserved COOH terminus of the protein. The seven mutations were found in 10 families (3.7%). In addition, one missense variant, L1420F, was observed in 13 HBOC families (4.8%) but was not observed in any of the 122 healthy volunteers with no history of breast cancer. In addition, the variant segregated with breast cancer in some of the families, suggesting that it may be pathogenic for breast cancer. Sixty-two additional variants of potential significance were observed in 65 HBOC families, but not in healthy controls. These variants included 24 sequence alterations with possible effects on splicing or protein-protein interactions. This study indicates that there is a significant prevalence of ATM mutations in breast and ovarian cancer families and adds to a growing body of evidence that ATM mutations confer increased susceptibility to breast cancer.  相似文献   
988.
Prophylactic oophorectomy: a morphologic and immunohistochemical study   总被引:2,自引:0,他引:2  
BACKGROUND: The tumorigenesis of ovarian carcinoma is poorly understood. The authors studied morphologic features and immunohistochemical expression patterns of neoplasia-associated markers in prophylactically removed ovaries, normal ovaries, and papillary serous ovarian carcinomas to identify possible preneoplastic changes in ovarian surface epithelium. METHODS: Morphologic features and immunohistochemical expression patterns of CA-125, Ki-67, p53, E-cadherin, and Bcl-2 were evaluated in 21 normal ovaries, 31 ovaries that were removed prophylactically for increased carcinoma risk, and 7 ovarian papillary serous carcinomas. Representative slides from formalin-fixed, paraffin-embedded tissue blocks were submitted to immunohistochemical staining and were evaluated independently by three gynecologic pathologists. For statistical analyses, Fisher exact tests, multivariate analyses, Spearman rank correlation coefficients, Wald statistics, Kruskal-Wallis tests, and Mann-Whitney tests were used. Immunohistochemical staining results were correlated with morphologic findings. RESULTS: The authors found progressive increases in reactivity with the lowest expression in normal ovarian epithelium, stronger expression in epithelium from prophylactically removed ovaries, and the highest expression in carcinomas for Ki-67 and p53. A similar trend was observed for CA-125. Positivity for Ki-67 and p53 was seen predominantly in the epithelium of inclusion cysts and deep invaginations, including those areas that had been identified as hyperplastic or dysplastic on routine hematoxylin and eosin-stained sections. CONCLUSIONS: The current results suggest biologic/molecular evidence for the existence of preneoplastic changes in ovarian surface epithelium and support the previously proposed concept of ovarian dysplasia. Subtle morphologic alterations of the ovarian epithelium may be biologically significant.  相似文献   
989.
990.
During a period of about three years the faeces of five species of amphibians (35 individuals) and of 23 species of reptiles (103 individuals) living in one vivarium with terrariums imitating different types of ecosystems were examined for salmonellae. From 54 out of 376 faecal samples Salmonella spp. was isolated (= 14%). Twenty-one different Salmonella strains were found. Salmonellae could be isolated about twice as often from animals kept under arid or mesic conditions than from animals living in humid or aquatic environments although this was not statistically significant. Statistically significant for the rate of Salmonella excretion was the animals' diet and the class the animals are belonging to. Animals feeding on mice (p = 0.04) and reptiles in general (p = 0.04) were more commonly excreting Salmonella. Duration of stay was also a significant factor (p = 0.0005), whereby the relative risk for Salmonella excretion increased with the factor 2.91 per year during the investigation period. Salmonella strains were not necessarily transferred among animals living in the same terrarium or among the inhabitants of different terrariums. The pattern of Salmonella excretion was generally fragmentary. The outsides as well as the insides of the walls of the terrariums were also tested for salmonellae several times, but salmonellae have never been isolated.  相似文献   
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