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11.

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   

12.
In the current study, the creep properties of magnesium alloy reinforced with SiC particles were investigated. For this purpose, ZK60/SiCp composite was produced by the stir casting method following the KoBo extrusion and precipitation hardening processes. The creep tests were performed at 150 °C under 10–110 MPa. The results showed that the stress exponent (n) and the average true activation energy (Q) was changed at high stresses, was found with increasing stress, the creep mechanism changing from grain boundary sliding to dislocation climb. The results of microstructure characterization after the creep test showed that at low stresses, the dynamic recrystallization resulting from twinning induced the GBS mechanism. However, at high stresses, with increasing diffusion rates, conditions are provided for dynamic precipitation and the dislocation climb of the dominant creep mechanism. Examination of the fracture surfaces and the surrounding areas showed that the cavity nucleation in the ternary boundary and surrounding precipitation was the main cause of damage. The evaluation of the samples texture after creep showed that the unreinforced alloy showed a moderately strong fiber texture along the angle of ϕ1 = 0–90°, which was tilted about Φ = 10°. A new strong texture component was observed at (90°, 5°, 0°) for the composite sample, which crept due to minor splitting of the basal pole by ~5° toward RD.  相似文献   
13.
The purpose of the present article is to study the bending strength of glulam prepared by plane tree (Platanus Orientalis-L) wood layers adhered by UF resin with different formaldehyde to urea molar ratios containing the modified starch adhesive with different NaOCl concentrations. Artificial neural network (ANN) as a modern tool was used to predict this response, too. The multilayer perceptron (MLP) models were used to predict the modulus of rapture (MOR) and the statistics, including the determination coefficient (R2), root mean square error (RMSE), and mean absolute percentage error (MAPE) were used to validate the prediction. Combining the ANN and the genetic algorithm by using the multiple objective and nonlinear constraint functions, the optimum point was determined based on the experimental and estimated data, respectively. The characterization analysis, performed by FTIR and XRD, was used to describe the effect of the inputs on the output. The results indicated that the statistics obtained show excellent MOR predictions by the feed-forward neural network using Levenberg–Marquardt algorithms. The comparison of the optimal output of the actual values obtained by the genetic algorithm resulting from the multi-objective function and the optimal output of the values estimated by the nonlinear constraint function indicates a minimum difference between both functions.  相似文献   
14.
Background:Despite newer therapeutic approaches against glioblastoma multiforme (GBM), the severely poor prognosis and treatment resistance are still disadvantages that slow down the patient’s recovery process. Consistent with the need to develop more effective and optimized therapies to control GBM cell growth, the effects of a new series of tetrahydrobenzo(g)imidazo[α-1,2]quinolone derivatives on GBM cell growth and the underlying mechanism is investigated in the current study. Methods:U-87MG cell line, glioblastoma multiforme and normal skin fibroblast cell line, AGO1522 were used to study the anticancer effects of 5 derivatives of tetrahydrobenzo(g)imidazo[α-1,2]quinolone and paclitaxel as a standard drug. The cytotoxic effect on cell growth was assessed using the MTT assay. Annexin V FITC staining and PI staining were applied to detect apoptosis and cell cycle distribution using flow cytometry. The extent of reactive oxygen species (ROS) formation was assessed using the fluorescent probe 7-dichlorofluorescin diacetate and caspase-3 activity using the colorimetric assay kit. Results:Among the 5 derivatives of tetrahydrobenzo(g)imidazo[α-1,2]quinolone, the 5c derivative (5-(6-bromo-2-chloroquinolin-3-yl)-9a-hydroxy-8,8-dimethyl-4-Nitro-2,3,5,5a,7,8,9,9a-octahydroimidazo[α-1,2]quinoline-6(1H)) showed the strongest cytotoxic effect on U-87MG cells in a time and Dose-dependent manner compared to the other derivatives and paclitaxel. The IC50 (11.91 M) of the 5c derivative induced apoptosis accompanied by a significant increase in sub-G1 and super-G2 phases of U-87MG cells. The increased level of cellular ROS and caspase 3 activity after treatment of U-87MG cells with 5c derivative was significant compared to untreated cells. Conclusion:Our data provide insights into the potent anticancer effects of the 5c-derivative of tetrahydrobenzo(g)imidazo[α-1,2]quinolone on GBM cells via the caspase-dependent apoptotic pathway, which may merit further attention.Key Words: Glioblastoma multiforme, imidazoquinoline, apoptosis, ROS, reactive oxygen species  相似文献   
15.
Both human and animal studies indicate that the dentate gyrus (DG) of the hippocampus is highly exploited by drug and alcohol abuse. Yet, it is poorly understood how DG dysfunction affects addiction-related behaviors. Here, we used an animal model of alcohol use disorder (AUD) in automated IntelliCages and performed local genetic manipulation to investigate how synaptic transmission in the dorsal DG (dDG) affects alcohol-related behaviors. We show that a cue light induces potentiation-like plasticity of dDG synapses in alcohol-naive mice. This process is impaired in mice trained to drink alcohol. Acamprosate (ACA), a drug that reduces alcohol relapse, rescues the impairment of dDG synaptic transmission in alcohol mice. A molecular manipulation that reduces dDG synaptic AMPAR and NMDAR levels increases impulsive alcohol seeking during cue relapse (CR) in alcohol mice but does not affect alcohol reward, motivation or craving. These findings suggest that hindered dDG synaptic transmission specifically underlies impulsive alcohol seeking induced by alcohol cues, a core symptom of AUD.Subject terms: Addiction, Cellular neuroscience  相似文献   
16.
BackgroundNowadays, neonatal screening has become an essential part of routine newborn care in the world. This is a non‐invasive evaluation that evaluated inborn errors of metabolisms (IEMs) using tandem mass spectrometry (LC‐MS/MS) for the evaluation of the baby''s risk of certain metabolic disorders.MethodsThis retrospective study was conducted on 39987 Iranian newborns who were referred to Nilou Medical Laboratory, Tehran, Iran, for newborn screening programs of IEMs. We incorporated second‐tier tests and secondary biomarkers to improve positive predictive value (PPV).ResultsStatistical data were recorded via call interviewing in 6–8 months after their screening tests. The overall prevalence of IEM was 1:975. The mean age of all participants was 3.9 ± 1.1 days; 5.1% of participants were over 13 days and 7.7% were preterm or underweight. A total of 11384 (29.4%) of the cases were born in a consanguineous family. The type of delivery was the cesarean section in 8332 (51.3%) valid cases. The neonatal screening results had an overall negative predictive value (NPV) of 100% and the overall PPV of 40.2%. The false‐positive rate was 0.15%.ConclusionThis study showed a high incidence of metabolic disease due to a high rate of consanguineous marriages in Iran and indicated that incorporation of second‐tier tests and secondary biomarkers improves PPV of neonatal screening programs.  相似文献   
17.
A primigravida 26‐year‐old woman who had developed pre‐eclampsia with malignant hypertension at 30 weeks of gestation suffered acute myocardial infarction two days postpartum. Electrocardiogram demonstrated diffuse ST‐segment depression suggestive of subendocardial ischemia. Echocardiography demonstrated focal asymmetric left ventricular hypertrophy, with a characteristic “basal septal bulge”, and a left ventricular mid‐cavitary gradient of 51 mmHg. Coronary angiography revealed normal coronary arteries and vascular flow. Peripartum acute myocardial infarction is rare and portends a high mortality. However, to date, only one case of acute myocardial infarction associated with asymmetric left ventricular hypertrophy and pre‐eclampsia has been described in the literature.  相似文献   
18.
Objective. To evaluate the effect of six weeks of high intensity interval training (HIIT) and L-Arginine supplementation on interleukin-6 (IL-6) levels and body composition in Iranian adult trained males. Methods. This experimental study was performed as an intervention with a pretest-posttest design in three experimental groups and one control group. Forty-eight young males from Qazvin province (Iran) were selected voluntarily based on convenience sampling. Participants were randomly divided into four groups (12 participants in each group): “HIIT”; “L-Arginine supplementation”; “HIIT + L-Arginine supplementation”, and “HIIT + placebo”. At 7 a.m., when the level of inflammation was at its lowest, a blood sample was taken from the participants, and body mass index (BMI), body fat percentage (BFP), and lean body mass (LBM) were determined. IL-6 analysis was performed using STATE FAX device and ELISA method. Training sessions were conducted for six consecutive weeks, three sessions a week. Analysis of covariance and Bonferroni post hoc test were used to analyze the data. Results. i) There were no significant differences between groups in BMI, BFP, or LBM. ii) There was a significant difference in IL-6 levels between the groups (p < 0.05), so that the inflammatory levels in the “HIIT + L-Arginine supplementation” and “HIIT + placebo” groups were lesser than the “HIIT” (0.002 and <0.001, respectively) and “L-Arginine supplementation” (<0.001and <0.001, respectively) groups. HIIT “seems” to reduce the level of inflammation. Conclusion. HIIT had no significant effect on body composition indices. Plasma IL-6 levels decreased after six weeks of HIIT and L-Arginine supplementation. The level of IL-6 in the “HIIT + L-Arginine supplementation” and “HIIT + placebo” groups were lower than the control group (i.e.; “HIIT”) and supplement control group (i.e.; “L-Arginine supplementation”).  相似文献   
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