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81.
Purpose: To determine if adequate anaesthesia and akinesia could be obtained using an inferonasal quadrant sub-Tenons anaesthesia for cataract surgery.
Methods: The sub-Tenons method of local anaesthesia was used in 50 patients undergoing extracapsular cataract extraction and lens implantation. The technique followed was that described by JD Stevens in his study of 50 patients. Posterior sub-Tenons space was approached through a conjunctival incision in the inferonasal quadrant and the anaesthetic solution delivered by an irrigating cannula. The patients were assessed for residual ocular movements just before surgery. Effectiveness of anaesthesia was assessed during surgery using a verbal pain rating score. Scoring was based on the concept of a visual analogue pain score chart.
Results: Total akinesia was obtained in 20% patients and total anaesthesia in 24% patients. The remainder of the patients had adequate akinesia and anaesthesia to proceed with and complete the surgery.
Conclusion: This method provides satisfactory anaesthesia for cataract surgery.  相似文献   
82.
Summary A specific radioimmunoassay for the quantitative measurement of ACTH 4-10 and a procedure for its extraction from plasma have been developed.Its pharmacokinetics was studied in eight healthy male volunteers given ACTH 4-10 125 µg/kg body weight as a bolus i.v. injection, by infusion and intranasally. Following the i.v. bolus, plasma levels rapidly declined biexponentially, with half-lives of 0.39±0.05 min for the -phase and 3.84 ± 1.5 min for the -phase (mean±SD). The constant rate i.v. infusion yielded steady-state levels between 0.74 and 5.06 ng/ml plasma. Administered as intranasal spray, absorption of intact ACTH 4-10 was low and variable (maximal bioavailability 7.6%).The results are discussed in relation to the dose-dependent effects of ACTH 4-10 on the auditory evoked potential.  相似文献   
83.
A high-performance liquid chromatographic (HPLC) method is described for the assay of the active metabolite [1-(2-pyrimidinyl)piperazinel of buspirone, an anxiolytic agent, in rat plasma.

The method is based on the use of ion-pair HPLC coupled to a liquid—solid extraction scheme. Samples of rat plasma (2 ml) with internal standard (1-phenylpiperazine), adjusted to pH 10.5 with borate buffer, were loaded on to a preactivated C-18 cartridge. The metabolite and the internal standard were eluted with 5 ml of methanol and injected on to a reversed-phase 10-μm Spherisorb ODS-2 column. The column was eluted with a mobile phase of 0.005 M sodium lauryl sulphate in citrate buffer (pH 3.6)-acetonitrile (65:35, v/v) at 2 ml min−1. Detection was carried out at 248 nm. The recovery of the metabolite was 55%. The method was applied to the determination of the metabolite in rat plasma after oral dosing (25 mg kg−1) of the parent compound.  相似文献   

84.
85.
目的 探究SMILE术后眼压的预测并校正。方法 回顾性研究+前瞻性验证。纳入2019-12/2021-12于中部战区总医院行SMILE的患者90例(180眼),随机抽取30眼为验证集,余150眼为训练集。前瞻性录入2022-01/2022-09SMILE的51例(102眼)为测试集。首先分析训练集手术前3d、术后1wk、1mo、3mo及6mo的眼压情况,确定眼压稳定期及于术前的眼压变化量(ΔIOP);再选取球柱镜代数和(SC)、球镜度(DS)、柱镜度(DC)及眼压(IOP)、中央角膜厚度(CCT)、角膜平均曲率(Km)、前房深度(ACD),眼压稳定时的变化量(ΔCCT、ΔKm、ΔK1、ΔK2、ΔACD)及个体因素,纳入与ΔIOP相关的因素拟合回归模型;最后建立适合临床SMILE术后眼压预测及校正的公式并作效能验证。结果 除术后1wk、3mo及6moIOP三者间无明显差异外,余时段IOP间差异均有统计学意义(P<0.05);各因素与ΔIOP拟合最佳回归方程:ΔIOP=0.459IOP术前-0.183SC-0.041Age+1.292ΔACD-1.270(调节R2=0.533,P<0.001)。仅纳入术前IOP和SC,拟合简化方程:ΔIOP=0.496IOP术前-0.194SC-2.952(调节R2=0.498,P<0.001);预测和校正公式:IOP术后预测=0.5IOP术前+0.2SC+3,IOP术后校正=IOP术后+0.5IOP术前–0.2SC–3。简化公式的效能验证显示良好。结论 SMILE术后3月IOP趋于稳定,且ΔIOP与屈光度相关。SMILE术后IOP可通过简化公式作快速临床预测和校正。  相似文献   
86.
Antibacterial reagents, especially quinolones, are widely used in animals and humans, and have caused serious problems to human health because of their residual contaminants in food. In order to screen for different kinds of newquinolones at the same time, a sensitive and specific enzyme-linked immunoassay (ELISA) has been developed. The anti-enrofloxacin monoclonal antibody was selected because of its ability to react with structurally related newquinolones in organic solvent. The antibody has 100% cross-reactivity with norfloxacin, ciprofloxacin and other newquinolones at 50% inhibition of control values IC50, but not with nitroflazone, sulphadimethoxine. The lowest detection limit of this ELISA was 0.7 ng/ml (ppb) when enrofloxacin was used as the calibrator. Eel extracts were spiked with enrofloxacin and the average recoveries at 10, 50, 100 ng/ml were 98, 102 and 91%, respectively. The proposed ELISA is a useful method for the practical microquantitation of various newquinolones in biological and environmental specimens.  相似文献   
87.
以生理信号分析为主,表情行为观察和情绪主观感受评价为辅,对多名被试的情绪进行识别.60名大学女生接受恐惧-快乐-轻松的情绪诱发,有效数据55名,对应每个情绪片段,根据信号标记以及GSR微分,截取1min的生理信号进行处理和分析,应用SPSS对各生理参数进行情绪的单因素方差分析,然后采用逐步多类判别法,提取特征参数以识别情绪.结果表明HR、HRV、R波、T波各生理参数对情绪较敏感;提取出HFP,HR max,PNN50,LF/HF,Ratio,LFP,Mean NN 7个特征参数,构建情绪判别函数Fuction1,Fuction2和Z1、Z2,Z3;轻松的判别正确率为88.0%,快乐的为92.0%,恐惧的为80.0%,总体判别正确率为86.7%.以生理信号分析为主,辅助表情行为观察和情绪主观感受报告,是一种有效的情绪识别方法,所得数据客观、准确,提高了情绪识别率.  相似文献   
88.
根据呼气相胸片中肺部区域灰度较高的特点,通过边缘提取和边缘跟踪确定胸部区域,运用最大类间方差方法确定图像分割的阈值.再提取出肺部区域,然后求出肺部的灰度均值。但这样的结果并不理想。于是在此基础上提出修正方案,即以肺部灰度均值和骨骼灰度均值的比值作为特征值.即比例法。此方法可以较客观的识别呼气相胸片。最后用类间距离对这两种方法进行了量化比较。  相似文献   
89.
多发性硬化症(MS)是一种严重威胁中枢神经功能的疾病,利用磁共振成像技术能够无损伤地检出其病灶。为了自动地对多发性硬化症病灶进行分割,提出了基于模糊连接度的分割算法,实现了种子点的自动选取。作为多发性硬化症分割的预处理,针对脑部MR FLAIR图像的特征,基于区域增长方法,还提出了脑部组织提取算法。通过对临床患者MR图像的分割实验,表明该分割算法能够比较准确地分割多发性硬化症病灶,其分割效果明显好于模糊C-均值聚类算法和基于马尔可夫场模型的分割算法。该算法还具有无监督、运算速度快、稳健性好等优点,能够应用于多发性硬化症的临床辅助诊断。  相似文献   
90.
BACKGROUND: This study was carried out to evaluate whether bilateral orchidopexy represents a poor or good prognostic factor in azoospermic men undergoing testicular sperm extraction (TESE). METHODS: One hundred and seven presumed non-obstructive azoospermia (NOA) patients, according to conventional clinical parameters (volume of testis, FSH, clinical history) were submitted to testicular biopsy with TESE. Thirty men (28%) had a history of bilateral orchidopexy for cryptorchidism. RESULTS: Normal spermatogenesis or mild hypospermatogenesis was diagnosed in 12/30 ex-cryptorchid patients and in 7/77 presumed NOA patients (P = 0.0004). Conversely, pure Sertoli cell-only syndrome or complete maturation arrest was found in 10/30 ex-cryptorchid patients and in 48/77 presumed NOA patients (P = 0.0094). In 53/107 patients (49.5%), TESE allowed a positive sperm retrieval. At least one spermatozoon was observed in 22/30 ( approximately 73%) ex-cryptorchid patients and in 31/77 ( approximately 40%) presumed NOA patients (P = 0.0026). A large number of spermatozoa (equivalent to an obstructive pathology) were retrieved in 13/30 ex-cryptorchid and in 10/77 presumed NOA patients (P = 0.001). A history of bilateral orchidopexy in presumed NOA patients correlates positively for the chance of retrieving testicular spermatozoa (odds ratio 3.8; 95% confidence interval 1.41-10.21; P = 0.008). CONCLUSIONS: Although bilateral cryptorchidism is usually considered a testicular secretive dysfunction, TESE permits retrieval of a large number of spermatozoa in almost 40% of cases. Our data suggest the existence of congenital or acquired obstructive anomalies of the seminal ducts in azoospermic orchidopexed men.  相似文献   
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