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The aim of this study was to evaluate the effect of 940 nm laser diode on class II composite cavities prior to bonding and restoration process on the postoperative sensitivity (POS). Thirty patients with two bilateral premolars with mesio or disto-occlusal carious lesions were evaluated. In each patient, the teeth were randomly divided into the control and laser groups. After cavity preparation and isolation and before the bonding process, the laser group was subjected to 940 nm irradiation (Epic 10, Biolase, USA) by 400 μ tip continuously at 100 mW with 398 J/cm2 energy density of tip, which was applied for 5 s at a distance of 2 mm on the axial wall of the cavity. In the control group, irradiation was performed by using the aiming beam. Access cavity was then restored with a composite resin. Cold sensitivity was measured using a cold spray application on the middle third of teeth buccal surface at baseline (before the intervention), 1, 14, and 30 days after the restoration by visual analog scale (VAS) criteria. The mean Friedman and Wilcoxon signed-rank tests were used for data analysis. It was shown that in both laser and control groups, the VAS was significantly decreased at all times compared to the baseline (p ≤ 0.05). There was no statistically significant difference between the mean VAS of two groups at baseline and first day (p ≤ 0.05), but at 14 and 30 days after the intervention, it was significantly lower in the laser group (p ≤ 0.05). The results of this study demonstrated that the cavity pretreatment with laser diode (940 nm) effectively reduces the postoperative sensitivity in class II composite restorations.

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Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.  相似文献   
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Purpose Traumatic hemorrhagic shock is a life-threatening event worldwide.Severe brain trauma accompanying femoral fractures can trigger inflammatory responses in the body and increase pre-inflammatory cytokines such as TNF-α,IL-1.The primary treatment in these cases is hydration with crystalloids,which has both benefits and complications.The purpose of this study was to investigate the effects of fluid therapy on the hemodynamics,coagulation profiles,and blood gases in such patients.Methods In this cross-sectional study,patients were divided into two groups:femoral fracture group and non-femoral group.The hemodynamic status,coagulation profile,and blood gases of patients in both groups were evaluated upon arrival at the hospital and again 2 h later.Data were analyzed by t-test and ANOVA with repeated data and paired samples t-test.Results A total of 681 trauma patients(605 men and 76 women)participated in this study,including 69(86.3%)men and 11(13.8%)women in femoral fracture group and 536 men(89.2%)and 65 women(10.8%)in non-femoral group.The laboratory parameters were evaluated in response to the equal amount of crystalloid fluid given upon arrival and 2 h later.Blood gases decreased in the fracture group despite fluid therapy(p<0.003),and the coagulation profile worsened although the change was not statistically significant.Conclusion The treatment of multiple-trauma patients with femoral bone fractures should be more concerned with the need for the infusion of vasopressors such as norepinephrine.If there is evidence of clinical shock,excessive crystalloid infusion(limited to 1 L)should be avoided,and blood and blood products should be started as soon as possible.  相似文献   
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OBJECTIVE: The purpose of this study was to describe outcomes for patients with trauma who had vena caval filters placed in the absence of venous thromboembolic disease (group P) and compare them with outcomes for patients with trauma who had filters placed after either deep venous thrombosis or pulmonary embolism (group T). DESIGN: The study is a case series of consecutive patients who received vena caval filters after traumatic injury. Data were collected prospectively at the time of filter placement from reports of diagnostic studies obtained for clinical indications and during the annual follow-up examinations. Event rate findings are based on objective tests. Data were obtained from the Michigan Vena Cava Filter Registry. RESULTS: Filters were placed in 385 patients with trauma; 249 of these filters were prophylactic (group P). Event rates were similar in the two groups. New pulmonary embolism was diagnosed in 1.5% of the patients in group P and 2% of the patients in group T. Caval occlusion rates were 3.5% for group P and 2.3% for group T. In all, 15.6% of the patients in group P had deep venous thrombosis or pulmonary embolism after placement. The frequencies of lower extremity swelling and use of support hose were higher in group T than in group P (43% vs 25% and 25% vs 3.5%, respectively; P <.005). Outcomes were comparable in the two groups with respect to mechanical stability of the filter. CONCLUSIONS: The prophylactic indication for vena caval filter placement in patients with trauma is associated with a low incidence of adverse outcomes while providing protection from fatal pulmonary embolism. The current challenge is to limit the number of unnecessary placements through improved methods of risk stratification.  相似文献   
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Efficacy of the laparoscopic approach for anterior lumbar spinal fusion   总被引:2,自引:0,他引:2  
BACKGROUND: This study compares the immediate postoperative outcomes in patients who undergo laparoscopic and open anterior lumbar spinal fusion and describes the learning curve associated with the performance of this procedure. METHODS: The charts of patients who underwent anterior lumbar spinal fusion between January 1995 and July 1999 were reviewed. Data pertaining to the operation and postoperative course were analyzed and compared. RESULTS: Eighty-nine patients underwent anterior lumbar spinal fusion. Fourteen patients were excluded; a full analysis was performed on the records of the remaining 75 patients. Fifty-five patients underwent an attempted laparoscopic procedure, and 20 patients underwent an open procedure. The conversion rate was 38% (21/55 patients) in the group who underwent the laparoscopic procedure. In the 34 patients whose laparoscopic procedure was completed, there was significantly less blood loss and shorter postoperative ileus, but the operative time was longer, when compared with patients who underwent the open procedure. The laparoscopic procedures performed in 1999 resulted in fewer conversions, less blood loss, and a shorter operating room time, when compared with the laparoscopic procedures in 1998. CONCLUSIONS: Laparoscopic anterior lumbar spinal fusion improves immediate postoperative results when compared with open anterior lumbar spinal fusion.  相似文献   
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目的:研究开角型青光眼患者非穿透性深层巩膜切除术后高阶像差的变化。

方法:研究包括20例患者20眼, 其中10例为原发性开角型青光眼, 10例为继发性开角型青光眼。患者术前接受非穿透性深层巩膜切除术,并辅以Tenon囊下注射(0.02% of MMC)。术前及术后1、3mo用i-Trace分析仪测定角膜总高阶像差。每次随访时评估眼压(IOP)、最佳矫正视力(BCVA)和眼泡形态。手术的成功率分为完全成功、相对成功和失败。

结果:术前IOP为24.05±3.07 mmHg,平均用药2.85±0.67次,随访3mo后,IOP为12.30±3.32 mmHg,平均用药0.70±0.98次。随访期间IOP均明显下降(P<0.001)。术后随访1mo,总高阶像差(HOT)均方根(RMS)和总球型像差值明显升高,3mo后下降。术后各时间段三叶肌和全眼昏迷样像差变化无统计学意义。术后1mo HOT RMS及球形角膜均明显增加,3mo随访后明显减少。术后角膜三叶肌变化与术前相比无统计学意义。患者年龄和IOP对HOT和角膜HOT的变化无显著影响。

结论:深度巩膜切除术后1mo内角膜和眼部高阶像差增加,3mo后下降,与术前相比无统计学意义。在3mo随访时,患者的BCVA和等效球镜(SE)与术前相比无统计学差异。  相似文献   

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Background: Tobacco use is a significant predisposing factor to many diseases. Protection motivation theory is a well-suited theory, since fear can motivate individuals to change their unhealthy behaviors. Objective: This study was conducted to examine the associations between the constructs of this theory with intention and tobacco use behavior. Method: The present cross-sectional study was conducted in Noshahr, Iran. The participants were 440 high school boys selected using a stratified random sampling in 2016. A questionnaire about tobacco use based on protection motivation theory was developed and its validity and reliability were assessed. The questionnaire included the demographic information, the constructs of theory, and tobacco use behavior. Structural equation modeling was used to test the associations between the constructs with intention and tobacco use. Results: The variables of perceived vulnerability (β = 0/137, P < 0.001), fear (β = 0/149, P < 0.001), self-efficacy (β = 0/249, P < 0.001), perceived intrinsic reward (β = ?0.285, P < 0.001), threat appraisal (β = ?0.25, P < 0.001), and coping appraisal (β = 0.358, P < 0.001) had direct effect and are significant with intention. Moreover, perceived vulnerability (β = ?0.158, P < 0.001), fear (β = ?0.172, P < 0.001), self-efficacy (β = ?0.288, P < 0.001), perceived intrinsic reward (β = 0.329, P < 0.001), threat appraisal (β = 0.265, P < 0.001), and coping appraisal (β = ?0.379, P < 0.001) affected tobacco use indirectly through intention and were significantly associated with behavior. Also, intention had direct effect and is significant with tobacco use (β = ?1.156, P < 0.001). Conclusions: The protection motivation theory provides a useful framework for investigating factors of tobacco use among male students. Future tobacco prevention interventions should focus on increasing the vulnerability and fear, decreasing intrinsic reward, and improving self-efficacy to reduce tobacco use.  相似文献   
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