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991.
The purpose of this study was to analyze long-term follow-up information from patients treated with stenting for unprotected left main coronary artery (LMCA) stenosis. Stenting of unprotected LMCA stenosis is often performed in selected patients, but the long-term safety of this therapy is not yet established. Between January 1995 and September 2000, 270 consecutive patients with unprotected LMCA stenosis and normal left ventricular function who underwent treatment at 4 clinical centers were included in this study. Data were forwarded to the coordinating center using a standard case report form. The procedural success rate was 98.9%. There were no deaths, 3 stent thromboses, and 3 Q-wave myocardial infarctions during the hospitalization. Angiographic follow-up was performed in 237 patients (follow-up rate 87.8%), and the restenosis rate was 21.1%. The reference size was an independent predictor of binary restenosis (odds ratio 0.543, 95% confidence interval 0.308 to 0.957, p = 0.03). During the follow-up period (32.3 +/- 18.5 months), there were 20 deaths (8 cardiac, 12 noncardiac) and 5 nonfatal myocardial infarctions. Target and new lesion revascularizations were required in 45 (16.7%) and 31 (11.5%) patients, respectively. The cumulative probabilities free from major adverse cardiac events were 81.9 +/- 2.4%, 78.4 +/- 2.6%, and 77.7 +/- 2.7%, respectively, at 1, 2, and 3 years. Combined coronary artery disease and postprocedural minimal luminal diameter were the significant predictors of major adverse cardiac events. Thus, the long-term prognosis of patients after stenting of unprotected LMCA stenosis was favorable in selected patients with normal left ventricular function.  相似文献   
992.
Ceramide has been confirmed to be a signal mediator of apoptosis that is induced by tumor necrosis factor-alpha (TNF-alpha). It has also been reported that ceramide may induce insulin resistance as well as TNF-alpha. We investigated the effect of ceramide on insulin signaling pathways, such as insulin receptor (IR) beta-subunit, insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and protein kinase Czeta (PKCzeta) in rat adipocytes. We examined insulin-stimulated [(3)H]2-deoxyglucose (2-DOG) uptake in rat adipocytes pretreated with N-hexanoylsphingosine (C(6)-ceramide, 10 to 30 micromol/L). Insulin-induced 2-DOG uptake was significantly reduced by C(6)-ceramide pretreatment. We also examined the effect of various concentrations of C(6)-ceramide pretreatment on insulin-induced autophosphorylation of the IR beta-subunit, tyrosine phosphorylation of IRS-1, enzyme activity of PI3K, and membrane-associated PKCzeta immunoreactivity. Pretreatment with C(6)-ceramide significantly reduced autophosphorylation of the IR beta-subunit, tyrosine phosphorylation of IRS-1, and enzyme activity of PI3K. Moreover, membrane-associated PKCzeta immunoreactivity and immunoprecipitable PKCzeta enzyme activity, downstream of PI3K, were significantly suppressed by C(6)-ceramide pretreatment. These results suggest that ceramide may induce insulin resistance via the suppression of IRS-1-PI3K signaling, and subsequent activation of PKCzeta.  相似文献   
993.
BACKGROUND AND AIMS: The genetic contribution to inflammatory bowel disease (IBD) is under investigation. Recent evidence indicates a significant linkage between a locus on chromosome 19p13 and IBD. We investigated the association between an intercellular adhesion molecule 1 gene (ICAM-1) polymorphism located on chromosome 19p13 and IBD in a Japanese population. METHODS: We compared 207 Japanese patients who had IBD (79 with Crohn's disease (CD); 128 with ulcerative colitis (UC)) with 103 unrelated Japanese controls. We determined R241G and K469E polymorphisms of the ICAM-1 gene using polymerase chain reaction (PCR) techniques. RESULTS: Both frequency and carriage rate of the K469 allele were significantly higher in IBD patients than in controls (allelic frequency, p(c)=0.0026; carriage rate, p(c)=0.0034; odds ratio 2.59; 95% confidence interval 1.42-4.68). Furthermore, the frequency of the K469 allele was significantly increased in both CD and UC. Subgroup analysis demonstrated that both K469 allelic frequency and K469 carriage rate were significantly higher in patients with the small bowel and colon type of CD and entire colitis compared with healthy controls. CONCLUSIONS: We identified an overall association between IBD and ICAM-1 K469 in a Japanese population. Further studies of this chromosome region are required to elucidate the gene responsible for IBD.  相似文献   
994.
Encapsulating peritoneal sclerosis (EPS) remains one of the major causes of dropout in continuous ambulatory peritoneal dialysis by reducing ultrafiltration capacity. To demonstrate whether ascites from patients with EPS (EPS ascites) has fibroblast proliferation activity, we used NIH/3T3 fibroblasts to examine the effects of EPS ascites on fibroblast proliferation activity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Encapsulating peritoneal sclerosis ascites dose-dependently augmented NIH/3T3 fibroblast proliferation. The protein kinase C inhibitors and the tyrosine kinase inhibitors partially inhibited the stimulatory effects of EPS ascites on fibroblast proliferation activity. In EPS ascites, levels of interleukin (IL)-1beta, IL-6, IL-8, transforming growth factor (TGF)-beta1, hepatocyte growth factor (HGF), and platelet-derived growth factor (PDGF)-AB were elevated. The treatment with IL-1beta, HGF, TGF-beta1, and PDGF-AB alone or in combination at similar concentrations to those in EPS ascites exhibited small but significant fibroblast proliferation activities. We conclude that EPS ascites stimulate NIH/3T3 fibroblast proliferation via protein kinase C and tyrosine kinase. The elevated cytokine and growth factors partly contribute to the EPS ascites-induced fibroblast proliferation.  相似文献   
995.
Since acoustic properties of the myocardium are sensitive to the myocardial structure and the contractile conditions of myocyte, the authors evaluated cardiac dysfunction based on the integrated ultrasonic backscatter in 18 hemodialysis (HD) patients (duration: 102 +/- 84 months, mean age: 57.6 +/- 9.7 years) and 11 age-matched normals. The cyclic variation of integrated backscatter (CV-IB) at interventricular septum (IVS) and left ventricular posterior wall (PW) was measured and compared with percent fractional shortening (%FS) and percent wall thickening (%Th). The CV-IB of HD patients was smaller than that of control subjects (IVS: 6.2 +/- 1.1 dB vs 8.2 +/- 1.1 dB, p = 0.0003 and PW: 8.4 +/- 2.2 vs 10.3 +/- 1.3, p= 0.025). No significant difference was observed in %FS and %Th between HD patients and control subjects. In HD, the ratio of velocities of early diastolic inflow (E) to late atrial inflow was decreased (0.7 +/- 0.2 vs 1.1 +/- 0.7, p = 0.049) and deceleration time of E was prolonged significantly (200 +/- 28 msec vs 159 +/- 30 msec, p = 0.0082). In the absence of overt cardiac systolic dysfunction, myocardial damage indicated as a decrease in CV-IB and diastolic dysfunction identified on transmitral velocity waveform were detected, which may reflect from the myocardial fibrosis. As a mechanism, pressure overload, hyperparathyroidism, and anemia were neglected, and the other humoral factors may contribute to the myocardial damage in chronic renal failure.  相似文献   
996.
Proteome analysis of rat hepatic stellate cells   总被引:27,自引:0,他引:27  
Proteome analysis was performed on cellular and secreted proteins of normal (quiescent) and activated rat hepatic stellate cells. The stellate cells were activated either in vitro by cultivating quiescent stellate cells for 9 days or in vivo by injecting rats with carbon tetrachloride for 8 weeks. A total of 43 proteins/polypeptides were identified, which altered their expression levels when the cells were activated in vivo and/or in vitro. Twenty-seven of them showed similar changes in vivo and in vitro, including up-regulated proteins such as calcyclin, calgizzarin, and galectin-1 as well as down-regulated proteins such as liver carboxylesterase 10 and serine protease inhibitor 3. Sixteen of them showed different expression levels between in vivo and in vitro activated stellate cells. These results were reproducibly obtained in 3 independent experiments. The up-regulation of calcyclin, calgizzarin, and galectin-1, as well as the down-regulation of liver carboxylesterase 10 were directly confirmed in fibrotic liver tissues. Northern blots confirmed up-regulation of the messenger RNAs (mRNAs) of calcyclin, calgizzarin, and galectin-1 in activated stellate cells, indicating that these changes were controlled at the mRNA level. In addition a list compiling over 150 stellate cell proteins is presented. The data presented here thus provide a significant new protein-level insight into the activation of hepatic stellate cells, a key event in liver fibrogenesis.  相似文献   
997.
BACKGROUND AND AIM: The attenuated antisecretory activity observed during continuous administration of ranitidine has been described as tolerance. However, it remains unclear whether a similar phenomenon occurs with other histamine H2 receptor antagonists (H2RA). We investigated whether tolerance to famotidine, a stronger H2RA than ranitidine, occurs during long-term administration. METHODS: Seven healthy male Japanese subjects without Helicobacter pylori infection participated in a randomized cross-over study in which ranitidine and famotidine were administered for 14 days with a 4-week wash-out period. We performed 24-h intragastric pH monitoring on the first and 14th days of administration of each drug, and measured serum gastrin and plasma drug concentrations on the first, seventh and 14th days. RESULTS: The acid-inhibiting activity of ranitidine and famotidine declined during continuous administration. In particular, the potent nocturnal pH-increasing effect of the H2RA, which was observed on day 1, declined on day 14. Serum gastrin concentrations on day 14 were significantly lower than those on day 7, although plasma drug concentrations remained unchanged. CONCLUSION: Tolerance to famotidine occurs during continuous administration for 14 days, as previously shown in ranitidine studies.  相似文献   
998.
A 71-year-old man was admitted to our hospital because of systemic edema and exertional dyspnea. Chest radiographs revealed infiltrative shadows in both lung fields, pleural effusion, and pericardial effusion. Seven years before, he had undergone gastric surgery for a gastric ulcer with lymphoid hyperplasia. In the pathologic diagnosis based on the percutaneous lung biopsy, hyalinizing granuloma was suspected. For a more thorough diagnosis, the patient was subjected to an open lung biopsy, and the final diagnosis was low-grade B-cell lymphoma of the MALT (mucosa-associated lymphoid tissue) type. Gallium scintigraphy showed accentuated accumulation in the left neck and hypothyroidism was present. Histologic re-examination of the resected stomach revealed infiltration of centrocyte-like cells and lymphoepithelial lesions, compatible with the pathologic features of MALT lymphoma. We considered that the gastric neoplasm and the pulmonary, pleural, and thyroid tumors of MALT lymphoma had occurred seven years apart in this case. Thyroid hormone replacement and CHOP therapy improved the symptoms and decreased the lung tumor size by 73%. MALT lymphomas tend to remain localized for a long period. The multiorgan involvement seen in this case is rather rare.  相似文献   
999.
Vaccine-preventable viral infections in health care workers (HCWs) have been on the rise for the past 10 years in Japan. To reduce the viral infections and the burden of exposure follow-up surveys at a tertiary care hospital in Osaka, Japan, a seroprevalence survey was conducted, and free vaccinations for measles, rubella, varicella, and mumps were offered to newly hired HCWs (199 physicians and 72 nurses and nursing assistants) who had negative serologic results for antibodies against these viruses. Negative antibody titers were obtained from 7.4% of the newly hired HCWs for measles, 12.5% for rubella, 4.1% for varicella, and 15.9% for mumps. The vaccination program for HCWs improved the vaccine-preventable infection rates and resulted in fewer exposure follow-up surveys, fewer lost work days, and fewer HCWs requiring hospitalization for these viral infections compared with those counted for the previous year. These data indicate that all HCWs should be strongly recommended to be vaccinated against (or have documented immunity to) these viruses in Japan, as is the case in the United States.  相似文献   
1000.
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