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151.
152.
Background: It has been widely accepted that control of serum cholesterol levels is effective for prevention of cardiovascular events. Recent data have suggested that this is also the case in the elderly. Methods: A research group (chaired by T. Kita) was organized as part of the Comprehensive Research on Aging and Health conducted by the Japanese Ministry for Health, Labour, and Welfare in 1999–2002 to determine the best strategy for control of cholesterol levels in elderly Japanese with hypercholesterolemia. In order to do this a review of the literature was conducted. Conclusion: The research group concluded: (i) Japanese patients aged 65–74 years with hypercholesterolemia should be treated by following the Guideline for Diagnosis and Treatment of Atherosclerotic Cardiovascular Diseases by the Japan Atherosclerosis Society (2002), as cholesterol‐lowering therapy would bring a similar, or even larger, preventive effect to the elderly, whose absolute risk of cardiovascular events is higher than that in the younger population; (ii) target cholesterol levels in elderly Japanese aged ≥ 75 years with hypercholesterolemia should be determined individually according to their physical activities. It is noted that the elderly are more susceptible to drug‐related adverse effects than the younger since renal and liver functions, required for metabolizing drugs, in the elderly are relatively weaker.  相似文献   
153.
Botrocetin, a protein isolated from the venom of the snake Bothrops jararaca, induces platelet aggregation/agglutination by von Willebrand factor (vWF) binding to the membrane glycoprotein (GP) Ib, an action resembling that of ristocetin. However, some differences in the interaction between vWF and platelet GPIb induced by these two substances have been reported. We have recently shown that the GPIb binding domain on the vWF molecule, in both instances, resides in the tryptic 52/48 kDa fragment extending from amino acid residue 449 to 728 of the constituent subunit. In the present report, we demonstrate that botrocetin does not induce agglutination of formalin-fixed platelets from a patient with Bernard-Soulier syndrome congenitally lacking GPIb and GPIX as well as GPV, a finding similar to that shown with ristocetin. A monoclonal antibody against GPIb (AP-1) inhibits either ristocetin- or botrocetin-dependent vWF binding to formalin-fixed platelets from normal individuals. Therefore, botrocetin-induced vWF binding to formalin-fixed platelets may reflect the interaction between vWF and platelet GPIb. To strengthen this concept, we have now found that heightened botrocetin-induced type IIB vWF binding to platelet GPIb causes hyperagglutination of normal platelets.  相似文献   
154.
It is widely reported that cultured vascular smooth muscle cells (CVSMCs) from spontaneously hypertensive rats (SHR) show enhanced proliferation compared with cells from Wistar-Kyoto rats (WKY). The present studies were designed to find out whether this exaggerated proliferation in SHR is determined genetically and, if so, to evaluate the mechanism on the cell cycle. (1) Incorporation of [3H]thymidine into DNA was enhanced in CVSMCs from 3- and 12-week-old SHR compared with WKY but not in CVSMCs from DOCA-salt hypertensive rats compared with the cells from sham-operated rats. (2) DNA synthesis in SHR cells was enhanced further by addition of insulin (which is considered to be a progression factor) but not by arginine-vasopressin (AVP; considered to be a competence factor) or by angiotensin II (AII). On the other hand, insulin, AVP and AII significantly augmented DNA synthesis in WKY cells. (3) Intracellular free calcium concentration was slightly, but significantly, higher in SHR cells. (4) An increase in the population of DNA-synthesizing S-phase cells and decrease in (G2 + M)-phase cells in SHR were observed by flowcytometry. These data suggest (1) that enhanced DNA synthesis in CVSMCs from SHR is determined genetically, (2) that enhanced DNA synthesis in CVSMCs from SHR is largely dependent on an increased proportion of S-phase cells and (3) that this increase in S-phase cells in CVSMCs from SHR could be due to enhanced competence gene expression in SHR cells. (4) The increased intracellular free calcium concentration is compatible with an activation of the inositol-trisphosphate pathway.  相似文献   
155.
Diffuse intrahepatic recurrence after resection of hepatocellular carcinoma   总被引:4,自引:0,他引:4  
BACKGROUND/AIMS: An early diffuse type in the pattern of the postoperative intrahepatic recurrence of hepatocellular carcinoma has been recognized. The purpose of this study was to elucidate risk factors for diffuse recurrence of hepatocellular carcinoma. METHODOLOGY: The subjects involved in the present study were 114 patients with hepatocellular carcinomas resected in Tenri Hospital during the past 12 years. Univariate analysis was used for retrospective determination of the factors related to diffuse recurrences after surgery in 10 cases among 114 patients. RESULTS: The risk factors linked to diffuse recurrence were microscopical portal infiltration (P < 0.01), elevated alpha-fetoprotein (more than 1000 ng/mL) (P < 0.05), the absence of preoperative transcatheter arterial embolization (P < 0.01), and two or more segmentectomies of the liver (P < 0.01). Six of 10 patients with microscopical portal infiltration and elevated alpha-fetoprotein (more than 1000 ng/mL) had diffuse recurrence (P < 0.01). Six of 8 patients with two or more segmentectomies without preoperative TAE had diffuse recurrence (P < 0.01). CONCLUSIONS: When patients with the diagnosis of operable hepatocellular carcinoma have portal infiltration and elevated alpha-fetoprotein (more than 1000 ng/mL), two or more segmentectomies of the liver without preoperative transcatheter arterial embolization should be avoided.  相似文献   
156.
Journal of Natural Medicines - Two new steroidal saponins, scrobiculosides A and B, were isolated from the deep-sea sponge Pachastrella scrobiculosa, collected at a depth of 200&nbsp;m off...  相似文献   
157.
Predicting the response to immunosuppressive therapy could provide useful information to help the clinician define treatment strategies for patients with aplastic anemia. In our current study, we evaluated the relationship between telomere length of lymphocytes at diagnosis and the response to immunosuppressive therapy in 64 children with aplastic anemia, using flow fluorescence in situ hybridization. Median age of patients was ten years (range 1.5–16.2 years). Severity of the disease was classified as very severe in 23, severe in 21, and moderate in 20 patients. All patients were enrolled in multicenter studies using antithymocyte globulin and cyclosporine. The response rate to immunosuppressive therapy at six months was 52% (33 of 64). The probability of 5-year failure-free survival and overall survival were 56% (95% confidence interval (CI): 41–69%) and 97% (95%CI: 87–99%), respectively. Median telomere length in responders was −0.4 standard deviation (SD) (−2.7 to +3.0 SD) and −1.5 SD (−4.0 to +1.6 (SD)) in non-responders (P<0.001). Multivariate analysis showed that telomere length shorter than −1.0 SD (hazard ratio (HR): 22.0; 95%CI: 4.19–115; P<0.001), platelet count at diagnosis less than 25×109/L (HR: 13.9; 95%CI: 2.00–96.1; P=0.008), and interval from diagnosis to immunosuppressive therapy longer than 25 days (HR: 4.81; 95%CI: 1.15–20.1; P=0.031) were the significant variables for poor response to immunosuppressive therapy. Conversely to what has been found in adult patients, measurement of the telomere length of lymphocytes at diagnosis is a promising assay in predicting the response to immunosuppressive therapy in children with aplastic anemia.  相似文献   
158.
159.
To develop and evaluate a radiomics approach for classifying histological subtypes and epidermal growth factor receptor (EGFR) mutation status in lung cancer on PET/CT images. PET/CT images of lung cancer patients were obtained from public databases and used to establish two datasets, respectively to classify histological subtypes (156 adenocarcinomas and 32 squamous cell carcinomas) and EGFR mutation status (38 mutant and 100 wild-type samples). Seven types of imaging features were obtained from PET/CT images of lung cancer. Two types of machine learning algorithms were used to predict histological subtypes and EGFR mutation status: random forest (RF) and gradient tree boosting (XGB). The classifiers used either a single type or multiple types of imaging features. In the latter case, the optimal combination of the seven types of imaging features was selected by Bayesian optimization. Receiver operating characteristic analysis, area under the curve (AUC), and tenfold cross validation were used to assess the performance of the approach. In the classification of histological subtypes, the AUC values of the various classifiers were as follows: RF, single type: 0.759; XGB, single type: 0.760; RF, multiple types: 0.720; XGB, multiple types: 0.843. In the classification of EGFR mutation status, the AUC values were: RF, single type: 0.625; XGB, single type: 0.617; RF, multiple types: 0.577; XGB, multiple types: 0.659. The radiomics approach to PET/CT images, together with XGB and Bayesian optimization, is useful for classifying histological subtypes and EGFR mutation status in lung cancer.  相似文献   
160.

Background

Dendritic cells (DCs) may play an important role in forms of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis. DCs are generally recognized as initiators of acquired immunity and also serve as regulators of both innate and acquired immunity. We used the animal model of colitis induced by dextran sodium sulfate (DSS), and examined whether DCs prepared from the colon show immunoregulatory roles in the termination of DSS-induced colitis.

Methods

C57BL/6 mice exposed to DSS for 5 days developed acute colitis. DCs were isolated from the large intestinal lamina propria, and then analyzed for phenotypical, functional, and genetic data.

Results

Only PIR-A/Blow conventional DCs (cDCs) were detected in the steady state. However, after the treatment of DSS, PIR-A/Bhigh cDCs appeared and gradually increased from day 5 to day 7, at which time the DSS-induced colitis was terminated. Then, allogeneic mixed leukocyte reaction (MLR) was performed. The stimulatory activity of PIR-A/Bhigh cDCs obtained on day 7 was very low, and the addition of PIR-A/Bhigh cDCs suppressed the T cell proliferation in MLR, indicating the immunoregulatory role of PIR-A/Bhigh cDCs. The immunoregulatory role of PIR-A/Bhigh cDCs was confirmed by the in vivo transfer experiment, showing their therapeutic effect on DSS-induced colitis. The message level of TGFβi was significantly higher in PIR-A/Bhigh cDCs, while that of IFN-γ was highly upregulated in PIR-A/Blow cDCs, being well in accordance with the fact that PIR-A/Bhigh cDCs showed a suppressive function against activated T cells.

Conclusion

PIR-A/Bhigh cDCs showed a suppressive function against activated T cells by producing inhibitory cytokines.  相似文献   
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