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31.
Insomnia, depression, and anxiety disorder are common problems for people with neuropathic pain. In this study, mild noxious heat stimuli increased the duration and number of spontaneous pain‐like behaviors in sciatic nerve‐ligated mice. We used functional magnetic resonance imaging to visualize the increased blood oxygenation level‐dependent signal intensity in the anterior cingulate cortex (ACC) of mice with sciatic nerve ligation under mild noxious stimuli. Such stimuli significantly increased the release of glutamate in the ACC of nerve‐ligated mice. In addition, sciatic nerve ligation and mild noxious stimuli changed the morphology of astrocytes in the ACC. Treatment of cortical astrocytes with glutamate caused astrocytic activation, as detected by a stellate morphology. Furthermore, glutamate induced the translocation of GAT‐3 to astrocyte cell membranes using primary cultured glial cells from the mouse cortex. Moreover, the GABA level at the synaptic cleft in the ACC of nerve‐ligated mice was significantly decreased exposure to mild noxious stimuli. Finally, we investigated whether astrocytic activation in the ACC could directly mediate sleep disorder. With the optogenetic tool channel rhodopsin‐2 (ChR2), we demonstrated that selective photostimulation of these astrocytes in vivo triggered sleep disturbance. Taken together, these results suggest that neuropathic pain‐like stimuli activated astrocytes in the ACC and decreased the extracellular concentration of GABA via an increase in the release of glutamate. Furthermore, these findings provide novel evidence that astrocytic activation in the ACC can mimic sleep disturbance in mice. Synapse 68:235–247, 2014 . © 2014 Wiley Periodicals, Inc.  相似文献   
32.
A short sleep duration is expected to elevate blood pressure the next morning, but no report has evaluated this in detail using home blood pressure measurement. In this study, the relation between sleep duration and morning and evening home blood pressure and heart rate during seven consecutive days was evaluated. From 630 volunteers not receiving antihypertensive agents, we selected 478 subjects (318 male, 160 female; mean age: 39.0 years) whose 2-7 days of data consisted of 7-8 hours sleep duration (proper sleep period phase; mean sleep duration: 7.3 +/- 0.3 hours) and less than 7 hours (short sleep period phase; 5.7 +/- 4.9 hours). In the morning, systolic blood pressure and heart rate in the short sleep period phase (117.7 +/- 14.9 mmHg, 67.3 +/- 9.6/min) were significantly (p < 0.01) higher than those in the proper sleep period phase (116.9 +/- 14.9 mmHg, 66.5 +/- 9.1/min). However, there was no difference in morning diastolic blood pressure. Although the difference in morning systolic blood pressure had disappeared by the time of measurement before going to bed, the difference in heart rate was maintained (proper sleep period phase: 70.4 +/- 10.2/min, short sleep period phase: 71.7 +/- 10.7/min, p < 0.01). In conclusion, days with sleep duration of less than 7 hours showed higher morning systolic blood pressure and heart rate compared with days with sleep duration between 7 and 8 hours, but no difference was found in diastolic blood pressure. Moreover, although the difference in morning systolic blood pressure had disappeared at night, the difference in heart rate was still maintained.  相似文献   
33.
BACKGROUND: Abnormalities in the vascular function of insulin are observed in insulin resistance, and hyperglycaemia is one of the important factors inducing insulin resistance. OBJECTIVE: To investigate the role of glucose in the interaction of insulin and beta-adrenergic signalling systems in vascular smooth muscle cells (VSMC). METHODS: After cells were treated with D-glucose (525 mmol/l) and insulin (100 nmol/l), adenylyl cyclase activity was measured in the presence of isoproterenol, forskolin, and cholera toxin. Assays for insulin-induced activities of insulin receptor substrate (IRS)-1, phosphoinositide 3-kinase (PI3-K) and mitogen-activated protein kinase (MAPK) were performed. RESULTS: In the presence of low glucose concentrations (5 mmol/l), insulin enhanced isoproterenol-, forskolin- and cholera toxin-stimulated adenylyl cyclase activities. This stimulatory effect was abolished by PI3-K inhibitors, wortmannin, or LY294002. In contrast, in the presence of high glucose concentrations (25 mmol/l), insulin attenuated isoproterenol-stimulated activity but not cholera toxin- or forskolin-stimulated activity. Insulin-stimulated activities of IRS-1 and PI3-K, but not MAPK activity, were also attenuated in the presence of high concentrations of glucose. The MAPK kinase inhibitor, PD98059, abolished the inhibitory effect of insulin on the beta-adrenergic signalling system. Troglitazone and pioglitazone prevented this inhibitory effect of insulin by restoring IRS-1 and PI3-K activities. CONCLUSIONS: In the presence of low glucose concentrations, insulin stimulates the beta-adrenergic signalling system through the IRS-1/PI3-K pathway. However, in the presence of high glucose concentrations, the effect of insulin is switched to an inhibitory one, through the MAPK pathway. Our finding suggests that high glucose concentrations modify the cross-talk between insulin and the beta-adrenergic signalling systems in VSMC.  相似文献   
34.
We have studied the effects of recombinant human granulocyte colony-stimulating factor (rG-CSF) on granulopoiesis and neutrophil functions in aged rats and aged mice. We subcutaneously injected rG-CSF or control vehicle into aged rats (22 months old and 25 months old) for 7 consecutive days, counted the peripheral neutrophils and evaluated the functions of neutrophils isolated from venous blood. The peripheral neutrophil count in aged rats tended to be increased as compared with that in young rats (11 weeks old). However, the neutrophils in aged rats exhibited a decline of superoxide anion (O2-) release and phagocytic activity as compared with young rats. The peripheral neutrophil count in aged rats was significantly increased 5-6-fold as many as the control value by rG-CSF treatment, which was accompanied by a significant enhancement of O2- release and of phagocytic activity being restored to normal levels or better. In another series of experiments, we subcutaneously injected rG-CSF or control vehicle into aged mice (24-28 months old) or young mice (8 weeks old) for 7 consecutive days, and evaluated the functions of neutrophils isolated from peritoneal cavity. The peritoneal exudate neutrophils from the aged mice exhibited a decline of phagocytic and chemotactic activity as compared with the young mice. These functions in both young and aged mice were significantly enhanced by rG-CSF-treatment, and these functions in rG-CSF-treated aged mice were restored to a level higher than the level in control young mice. These findings demonstrate that rG-CSF is capable of enhancing granulopoiesis and restoring the age-related decline of neutrophil functions.  相似文献   
35.
AIMS: Endoscopic variceal ligation (EVL) is a recently developed alternative to endoscopic injection sclerotherapy (EIS) for the treatment of oesophageal varices. Endoscopic variceal ligation and EIS were compared in an attempt to clarify the efficacy and safety of EVL for patients with cirrhosis due to hepatitis C. METHODS: Endoscopic variceal ligation was performed in 60 patients and EIS in 30. Varices were eradicated in all patients by EVL and 87% (26 out of 30) by EIS. RESULTS: There was no significant difference between EVL and EIS in relation to the incidence of bleeding and the 5 year survival rate after treatment. There were no severe complications except mild substernal pain after EVL, while pulmonary embolism occurred in one patient receiving EIS. CONCLUSIONS: Endoscopic variceal ligation is a safe and effective technique for eradicating oesophageal varices in patients with hepatitis C cirrhosis.  相似文献   
36.
AIMS: A novel blood purification material that we previously reported as a superantigen- and cytokine-adsorbing device (SCAD) was evaluated for its ability to adsorb unbound, unconjugated bilirubin (UUBil) in vitro and in vivo. METHODS: In albumin-containing buffer, UUBil was dissolved and circulated through the SCAD column. Also, bilirubin was infused into low-body weight newborn piglets and hemoperfused for 3 h over SCAD columns. RESULTS: In albumin-containing buffer, concentration of bilirubin decreased from 34 to 0.6 mg/dL within 5 h and the SCAD fiber turned brown, indicating that bilirubin was adsorbed onto the surface of the adsorbent and was not degraded during the circulation. Using the hyperbilirubinemia swine, clearances of total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IdBil) were significantly higher (P<0.01) in the SCAD group compared with the control group. The clearances of TBil, DBil, and IdBil at 3 h after the initiation of the bilirubin infusion were 0.47, 0.53, and 0.45 mL/min, respectively, at a blood flow rate of 2.5 mL/min, and this result indicates that almost 20% of bilirubins were adsorbed to the SCAD column in a single passage. CONCLUSION: These results provide initial evidence that SCAD treatment is effective in the removal of UUBil and can be performed safely in newborn animals.  相似文献   
37.
Recently, it was reported that remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome could be complicated with solid tumors. In a retrospective, multicenter study between October, 2003 and September, 2010, we investigated the characteristics of patients with paraneoplastic RS3PE syndrome who fulfilled following criteria: (1) bilateral pitting edema of hands or feet or both, (2) sudden onset of polyarthritis, and (3) age >50?years, (4) seronegativity for rheumatoid factor (RF). A total of 33 cases fulfilled the above criteria. Eight patients (seven men and one woman) developed cancer within 2?years of RS3PE syndrome onset. There was no significant difference between the neoplastic and nonneoplastic groups in the proportions of patients with fever, symmetrical polyarthritis, pitting edema, and good response to corticosteroids. Serum matrix metalloproteinase 3 (MMP-3) level (median 437.3?ng/ml) in the paraneoplastic RS3PE patients was significantly higher than that in patients without neoplasia (median 114.7?ng/ml) (p?相似文献   
38.
39.
BACKGROUND AND AIMS: Helicobacter pylori infection and gastric atrophy are both risk factors for gastric cancer. We aimed to elucidate the natural history of gastric cancer development according to H pylori infection and gastric atrophy status.Subjects and METHODS: A total of 9293 participants in a mass health appraisal programme were candidates for inclusion in the present prospective cohort study: 6983 subjects revisited the follow up programme. Subjects were classified into four groups according to serological status at initial endoscopy. Group A (n = 3324) had "normal" pepsinogen and were negative for H pylori antibody; group B (n = 2134) had "normal" pepsinogen and were positive for H pylori antibody; group C (n = 1082) had "atrophic" pepsinogen and were positive for H pylori antibody; and group D (n = 443) had "atrophic" pepsinogen and were negative for H pylori antibody. Incidence of gastric cancer was determined by annual endoscopic examination. RESULTS: Mean duration of follow up was 4.7 years and the average number of endoscopic examinations was 5.1. The annual incidence of gastric cancer was 0.04% (95% confidence interval (CI) 0.02-0.09), 0.06% (0.03-0.13), 0.35% (0.23-0.57), and 0.60% (0.34-1.05) in groups A, B, C, and D, respectively. Hazard ratios compared with group A were 1.1 (95% CI 0.4-3.4), 6.0 (2.4-14.5), and 8.2 (3.2-21.5) in groups B, C, and D, respectively. Age, sex, and "group" significantly served as independent valuables by multivariate analysis. CONCLUSIONS: The combination of serum pepsinogen and anti-H pylori antibody provides a good predictive marker for the development of gastric cancer.  相似文献   
40.
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