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11.
《Clinical neurophysiology》2019,130(8):1280-1288
ObjectiveMotor Unit Number Estimation (MUNE) methods, such as the recently developed MScanFit MUNE (MScan), may be valuable in tracking motor unit loss in ALS. Muscle Velocity Recovery Cycles (MVRCs) provide information about muscle membrane properties and can reveal disease-related changes.This study was undertaken to test the applicability of MScan to the anterior tibial muscle (TA) and to test whether the MVRCs could improve understanding of ALS pathophysiology.MethodsTwenty-six ALS patients and 25 healthy controls were evaluated by quantitative electromyography, nerve conduction study and the two novel methods: MScan and MVRC; all in the TA and peroneal nerve.ResultsThe estimated number of motor units for ALS patients (Median: 45, interquartile range: 28.5–76.5) was significantly lower than for the controls (117, 96.0–121.0) (P = 2.19 × 10−7). Unit size was increased only when amplitudes were expressed as percentage of CMAP. Of MVRC measurements, only relative refractory period was significantly abnormal in patients.ConclusionMScanFit MUNE gives a sensitive and quantitative measure of loss of TA motor units in ALS. Muscle fiber membrane properties are mostly unaffected, despite substantial denervation, presumably due to collateral reinnervation.SignificanceMScan is suitable for detecting motor unit loss in TA. MVRCs do not provide new insights in ALS.  相似文献   
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目的探究超声测量颈内静脉内径呼吸变异度和血流速度在椎管内麻醉后血容量判断中的价值。方法选择我院2017年2月至2019年2月择期手术的椎管内麻醉患者120例,男64例,女56例,年龄为34~66岁,ASAⅠ或Ⅱ级。记录麻醉前、麻醉后5、15、25 min左侧颈内静脉最大直径(Dmax)、最小直径(Dmin)、内径呼吸变异度(RVI)、中心静脉压(CVP)、血流速度最大值(BVmax)、血流速度最小值(BVmin)和血流速度变异度(BVI),取CVP=6 mmHg作为预测值,并通过绘制ROC曲线来评估Dmax、Dmin、RVI、BVmax、BVmin和BVI的预测效能。结果与麻醉前比较,麻醉后5 min时Dmax、Dmin和BVI明显降低(P0.05),RVI明显升高(P0.05);与麻醉后5和15 min比较,麻醉后25 min,Dmax、Dmin和BVI明显升高(P0.05),RVI明显降低(P0.05)。麻醉前BVmin的AUC值最大为0.958,临界值6.86,敏感性82.6%,特异性95.2%;麻醉后5 min,Dmin的AUC值最大为0.944,临界值0.74,敏感性98.4%,特异性84.3%;麻醉后15 min,Dmin和BVmax的AUC值最大分别为0.949和0.945,临界值分别为0.72和7.99,敏感性分别为96.5%和89.8%,特异性分别为82.4%和82.1%;麻醉后25 min,BVmax的AUC值最大为0.981,临界值8.98,敏感性92.0%,特异性90.5%。结论超声测量患者颈内静脉的内径变异度和血流速度可作为预测椎管内麻醉后血容量的方式。  相似文献   
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目的:探讨冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证的疗效。方法:选择冠心病合并2型糖尿病患者98例,按随机数字表法分为对照组47例和观察组51例。对照组给予西医常规治疗措施; 观察组在对照组治疗基础上加用冠心康方加减治疗,1剂/次,2 次/d。连续治疗6个月后,比较两组血糖血脂水平、中医证候评分、脉搏波传导速度(PWV)以及临床疗效。结果:治疗后,观察组的空腹血糖(6.71±1.04)mmol/L、餐后2 h血糖为(10.63±1.94)mmol/L、HbA1c(7.13±0.97)%、TG(2.50±0.40)mmol/L,TC(3.94±0.55)mmol/L均低于对照组[(6.89±1.13)mmol/L、(10.93±2.03)mmol/L、(7.22±1.25)%、(2.53±0.36)mmol/L、(4.01±0.53)mmol/L],两组间比较差异有统计学意义(P<0.05)。治疗后观察组HDL-C(1.23±0.22)mmol/L 与对照组(1.19±0.21)mmol/L比较上升,而观察组LDL-C(2.61±0.34)mmol/L比对照组(2.67±0.37)mmol/L下降,组间比较差异无统计学意义(P>0.05)。治疗后,观察组患者中医证候评分(1.76±0.27)分及BS-PWV(5.90±0.64)m/s、ES-PWV(7.59±0.94)m/s均明显低于对照组的[(2.13±0.31)分、(6.41±0.77)m/s、(8.43±1.31)m/s](P<0.05)。观察组和对照组的总有效率分别为70.59%和59.57%,两组比较差异有统计学意义(P<0.05)。结论:冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证可有效改善患者的血糖、血脂、中医证候以及动脉硬化,提高临床疗效。  相似文献   
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Acrylamide (ACM) is a high-volume industrial chemical with diverse uses in manufacturing, construction and laboratory research. ACM is a well-established neurotoxic agent causing peripheral neuropathy with impairment in the arms and legs of exposed workers, most thoroughly studied in Swedish tunnel workers exposed to ACM grouting. A quantitative risk assessment was performed to assess ACM risk to workers. Using data from a published paper investigating peripheral neuropathies in Chinese chemical workers, estimates of exposure response for vibration perception threshold and nerve conduction velocities were calculated, based on hemoglobin adducts and air concentrations as exposure metrics. The benchmark dose procedure was applied in order to calculate excess risks of impairment, defined as adverse performance exceeding the 95th percentile in unexposed populations, at various concentrations of airborne ACM exposure. Under the assumptions in this risk assessment, after three years of inhalation exposure at 0.3 mg/m3, the excess attributable impairment manifest in vibration perception and nerve conduction velocity is estimated to occur in 1-2% of workers. For 10 years at 0.3 mg/m3 ACM inhalation (equivalent to 3 years at 1.0 mg/m3) the excess prevalence of impairment would be 2-14% of workers, assuming the effect continues to accrue linearly in time. Using published data, the risks of impairment from peripheral neuropathy attributable to exclusively airborne ACM exposure can be predicted for exposure periods less than 10 years. The risks associated with dermal and airborne ACM exposures can be estimated by characterizing working process environments using ACM Hb-adduct levels and possibly monitored with urinary biomarkers.  相似文献   
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Background and aimsConsuming pulses (dry beans, dry peas, chickpeas, lentils) over several weeks can improve vascular function and decrease cardiovascular disease risk; however, it is unknown whether pulses can modulate postprandial vascular responses. The objective of this study was to compare different bean varieties (black, navy, pinto, red kidney) and white rice for their acute postprandial effects on vascular and metabolic responses in healthy individuals.Methods and resultsThe study was designed as a single-blinded, randomized crossover trial with a minimum 6 days between consumption of the food articles. Vascular tone (primary endpoint), haemodynamics and serum biochemistry (secondary endpoints) were measured in 8 healthy adults before and at 1, 2, and 6 h after eating ¾ cup of beans or rice. Blood pressure and pulse wave velocity (PWV) were lower at 2 h following red kidney bean and pinto bean consumption compared to rice and navy bean, respectively (p < 0.05). There was greater vasorelaxation 6 h following consumption of darker-coloured beans, as shown by decreased vascular tone: PWV was lower after consuming black bean compared to pinto bean, augmentation pressure was lower after consuming black bean compared to rice and pinto bean, and wave reflection magnitude was lower after consuming red kidney bean and black bean compared to rice, navy bean, and pinto bean (p < 0.05). LDL-cholesterol concentrations were lower 6 h after black bean consumption compared to rice (p < 0.05).ConclusionOverall, red kidney and black beans, the darker-coloured beans, elicited a positive effect on the tensile properties of blood vessels, and this acute response may provide insight for how pulses modify vascular function.  相似文献   
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ObjectivesThis study sought to identify the factors associated with incident atrial fibrillation (AF) in a well-characterized heart failure with preserved ejection fraction (HFpEF) population, with special focus on left atrial (LA) strain.BackgroundAF is associated with HFpEF, with adverse consequences. Effective risk evaluation might allow the initiation of protective strategies.MethodsClinical evaluation and echocardiography, including measurements of peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and LA volume index (LAVI), were obtained in 170 patients with symptomatic HFpEF (mean age, 65 ± 8 years), free of baseline AF. AF was identified by standard 12-lead electrocardiogram, review of relevant medical records (including Holter documentation), and surveillance with a portable single-lead electrocardiogram device over 2 weeks. Results were validated in the 103 patients with HFpEF from the Karolinska-Rennes (KaRen) study.ResultsOver a median follow-up of 49 months, incident AF was identified in 39 patients (23%). Patients who developed AF were older; had higher clinical risk scores, brain natriuretic peptide, creatinine, LAVI, and LV mass; lower LA strain and exercise capacity; and more impaired LV diastolic function. PACS, PALS, and LAVI were the most predictive parameters for AF (area under receiver-operating characteristic curve: 0.76 for PACS, 0.71 for PALS, and 0.72 for LAVI). Nested Cox regression models showed that the predictive value of PACS and PALS was independent from and incremental to clinical data, LAVI, and E/e’ ratio. Classification and regression trees analysis identified PACS ≤12.7%, PALS ≤29.4%, and LAVI >34.3 ml/m2 as discriminatory nodes for AF, with a 33-fold greater hazard of AF (p < 0.001) in patients categorized as high risk. The classification and regression trees algorithm discriminated high and low AF risk in the validation cohort.ConclusionsPACS and PALS provide incremental predictive information about incident AF in HFpEF. The inclusion of these LA strain components to the diagnostic algorithm may help guide screening and further monitoring for AF risk in this population.  相似文献   
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《Clinical neurophysiology》2021,132(4):1000-1007
ObjectiveTo investigate early pre-treatment nerve fiber loss as a predictor of long-term clinical outcome in chronic inflammatory demyelinating polyneuropathy (CIDP).MethodsIn 14 patients, motor and sensory conduction studies of the median, fibular, and sural nerves were performed at pre-treatment and follow-up 11–28 years later. Z-scores of amplitudes were combined as biomarkers of axonal loss and Z-scores of conduction properties as demyelination scores. The axonal loss was further examined by electromyography (EMG) and motor unit number estimation. Axonal and demyelination scores were compared to clinical outcomes in the Inflammatory Rasch-built Overall Disability Scale, the Neuropathy Impairment Score, and dynamometry.ResultsAt follow-up 12 patients walked independently, one needed support and one could not walk. The initial and follow-up axonal and demyelination scores were markedly abnormal. The initial axonal loss but not demyelination was strongly associated with both the follow-up axonal loss and the clinical measures. Moreover, delay of treatment initiation negatively influenced the axonal scores and clinical outcomes.ConclusionIn this hypothesis generating limited study, we found that axonal loss at early CIDP was highly predictive for long-term nerve fiber loss and disability.SignificanceThe study indicates that prompt initiation of treatment to prevent nerve fiber loss is necessary for outcome in CIDP.  相似文献   
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建立华细辛和北细辛HPLC特征图谱并结合聚类分析研究2种来源细辛的识别方法;应用网络药理学方法预测细辛潜在抗炎靶点并寻找潜在抗炎成分。对89批细辛药材(12批华细辛和77批北细辛)的数据进行分析确定了11个特征峰,用对照品、紫外光谱和LC-MS指认了11个特征成分。特征峰面积聚类分析显示华细辛和北细辛被分为2类,且利用特征峰面积比值可实现两者区分,当特征峰9(细辛素)/参照峰S(卡枯醇)峰面积比值大于5时为华细辛,小于2时为北细辛。对119种细辛成分进行网络药理学分析的结果表明细辛抗炎作用可能与COX-2,COX-1,iNOS,MAPK14,LAT4H,NR3C1,PPARG和TNF等8个靶点相关,其中COX-2最为关键,与5种特征成分细辛脂素、芝麻脂素、细辛素、甲基丁香酚和黄樟醚均存在相互作用。此外,细辛脂素、芝麻脂素与iNOS,MAPK14也存在相互作用关系,黄樟醚和细辛素可作用于iNOS,COX-1,LAT4H,甲基丁香酚可作用于COX-1,LAT4H。细辛脂素与芝麻脂素均可作用在COX-2,iNOS和MAPK143个靶点上,提示它们是细辛发挥抗炎作用的活性成分;COX-2分子对接结果和COX-2活性实验结果验证了细辛脂素、芝麻脂素可抑制COX-2活性,为细辛抗炎作用活性成分。基于HPLC特征图谱的华细辛和北细辛识别方法简便易行;预测到的细辛抗炎靶点和抗炎成分为完善细辛质量评价体系奠定了基础。  相似文献   
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