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41.
目的 了解变形链球菌表面蛋白和葡糖基转移酶基因疫苗单独及联合免疫对定菌鼠唾液变链菌和牙面菌斑的影响。方法  2 8d龄 Wistar大鼠 3 6只 ,随机分为 pc DNA3 - pac组、pc DNA3 - gtf B组、pc DNA3 - pac联合pc DNA 3 - gtf B组、变形链球菌灭活全菌组、pc DNA3空载体组和 PBS液组 ,进行三次双侧颌下腺腺周注射免疫 ,建立定菌鼠模型 ,作诱龋实验 3个月。唾液变链菌计数和菌斑计分。结果 唾液变链菌菌落计数和牙面菌斑计分在 pc D-NA3与 PBS组最高 ,其次为单基因疫苗免疫组 ,联合基因疫苗和灭活全菌细胞免疫组最低 ,各组间有显著性差异 ( P<0 .0 5 )。结论  pc DNA3 - gtf B和 pc DNA3 - pac具有明显的免疫抑菌作用 ,联合基因疫苗免疫优于单基因疫苗  相似文献   
42.
眶骨的改变在眶部疾病HR-MRI诊断中的作用   总被引:6,自引:0,他引:6  
目的:探讨眶骨的影像学所见及其在眶部疾病诊断中的作用。方法:回顾性分析诊断明确的眶部疾病80例的HR-MRI影像表现。80例中良性囊肿18例,外伤6例,炎性疾病6例,蝶骨嵴脑膜瘤9例,其他肿瘤41例。磁共振扫描采用1.5T GE Signa及Siemens Magnetom Sp63磁共振扫描机,用眶部表面线圈,SE系列常规轴位、冠状位及矢状位扫描,部分病例行脂肪抑制及增强扫描。结果:正常眶骨的HR-MRI表现为结构完整,边缘光整,皮质骨在T1WI及。T2WI上均为无信号区。15例眶骨受压迫性改变全见于良性囊肿的病例,骨质增生改变主要见于蝶骨脑膜瘤,2例骨折见于外伤病例,21例骨质破坏大多见于不同的恶性肿瘤病变中。结论:不同的眶部病变对眶骨的影响有差异,良性囊肿主要表现为眶骨受压迫性改变,蝶骨脑膜瘤多表现为骨质增生,外伤病例伴有眶骨骨折,恶性肿瘤病例常伴有眶骨的破坏。眶骨的改变对眶部疾病HR-MRI的诊断和鉴别诊断有重要作用。  相似文献   
43.
Post-polio syndrome (PPS) is characterized by new muscle weakness, atrophy, fatigue and pain developing several years after the acute polio. Some studies suggest an ongoing inflammation in the spinal cord in these patients. From this perspective, intravenous immunoglobulin (IvIg) could be a therapeutic option. We performed a double-blinded randomized controlled pilot study with 20 patients to investigate the possible clinical effects of IvIg in PPS. Twenty patients were randomized to either IvIg 2 g/kg body weight or placebo. Primary endpoints were changes in pain, fatigue and muscle strength 3 months after treatment. Surrogate endpoints were changes in cerebrospinal fluid (CSF) cytokine levels. Secondary endpoints were pain, fatigue and isometric muscle strength after 6 months. Patients receiving IvIg reported a significant improvement in pain during the first 3 months, but no change was noted for subjective fatigue and muscle strength. CSF levels of tumour necrosis factor- α (TNF- α ) were increased compared with patients with non-inflammatory neurological disorders. In conclusion, in this small pilot study no effect was seen with IvIg treatment on muscle strength and fatigue, however IvIg treated PPS patients reported significantly less pain 3 months after treatment. TNF- α was increased in the CSF from PPS patients. The results are promising, but not conclusive because of the low number of patients studied.  相似文献   
44.
Signals generated from muscles other than the muscle(s) of interest (cross talk) can confound the interpretation of surface electromyograms (EMGs). In this study, the amount of cross talk in surface EMGs of human hamstring muscles was estimated using a protocol in which the quadriceps femoris was electrically stimulated via the femoral nerve. EMGs were recorded from the vastus lateralis and the medial and lateral hamstring muscle groups. The amplitude of the EMG response of the vastus lateralis to electrical stimulation was adjusted to match that of its maximum voluntary effort (MVE) under isometric conditions. Subsequent power density spectrum analysis showed that the median frequencies of the signals generated by electrical stimulation and MVE were not significantly different. In conventional bipolar recordings, cross talk in lateral hamstring EMGs averaged 17.1% MVE and in medial hamstring EMGs 11.3% MVE (average-rectified values). The double differential technique significantly reduced cross talk to 7.6% MVE for the lateral hamstrings, and to 4.2% MVE for the medial hamstrings. The double differential technique appears to be more selective than the bipolar technique when recording EMGs from muscles with highly active neighbors and thus should be used in such situations. Software simulations of the double differential technique also appear to be more selective than the bipolar technique and may be used when the number of amplifiers available is limited.  相似文献   
45.
Functional imaging is ideally suited to monitoring the effect of specific therapy on disease processes. In this pilot study five patients with AIDS and Pneumocystis carinii pneumonia (PCP) were imaged with Indium-111 labelled pooled human immunoglobulin (111In-HIG) during infection and after therapy for PCP. The lung activity of t t tln-HIG, measured as a lung/heart ratio, was calculated in a study performed during infection with PCP and after therapy. In all five patients the lung/heart ratio of t t 1ln-HIG was reduced after treatment. The mean reduction in heart/lung ratio was 27% (range 12%-53%). If these results are confirmed by a larger study, 11In-HIG will be useful in monitoring the response of PCP to therapy in patients with AIDS.  相似文献   
46.
For investigating the effect of acupuncture on ischemic arrhythmia and its mech-anism, adult albino rats with ligated anterior descending branch of coronary artery as experimentalmodel were treated with or without acupuncture, and others with imitative operation but without bothcoronary artery ligation and acupuncture treatment were used as control. It was found in acupuncturegroup that the fibrillation-liability of ischemic myocardium was efficiently decreased, the affinity ofAch-M receptors on membranes of ischemic myocardium was markedly increased, and the tolerance ofischemic myocardium to atropine was elevated in the experiment of atropine inducing fibrillation.These results indicate that acupuncture may play a therapeutic role on ischemic arrhythmia throughactivating the activity of muscarine-like receptors of cholinergic nervous system.  相似文献   
47.
We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n  = 34), intermittent early onset (before 18  months of age, n  = 495), intermittent late onset (18–42 months of age, n  = 273) and unaffected ( n  = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1–14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%.  相似文献   
48.
目的用缺氧方法制备的肺源性心脏病(肺心病)大鼠为对象,研究肺心病中M2和β1受体抗体的含量及其与疾病的关系。方法选取健康雄性Wistar大鼠36只,随机分为3组:单纯缺氧组,缺氧加注射FeCl3组,健康对照组。SA-酶联免疫吸附测定(ELISA)法检测血清M2和β1受体抗体变化。最后处死大鼠观察心脏指标,并分析它与抗体滴度的相关性。结果血清中M2和β1受体抗体随缺氧时间延长而升高,滴度分别到第3周达高峰M2受体抗体为1∶80(单纯缺氧组)和1∶53(缺氧加注射FeCl3组),β1受体抗体为1∶60(单纯缺氧组)和1∶45(缺氧加注射FeCl3组),并且P/N值从第2周开始有阳性意义,到第3周同样达高峰M2和β1受体抗体分别为2.88(单纯缺氧组)、2.76(缺氧加注射FeCl3组)和3.25(单纯缺氧组)、3.99(缺氧加注射FeCl3组)。而肺心病大鼠心脏指标最终改变为R/(L+S)0.333±0.027(单纯缺氧组),0.348±0.033(缺氧加注射FeCl3组),R/BW×10-30.58±0.13(单纯缺氧组),0.60±0.15(缺氧加注射FeCl3组),(L+S)/BW×10-32.000±0.024(单纯缺氧组),2.081±0.037(缺氧加注射FeCl3组),并且抗体滴度与心脏改变呈正相关。结论M2和β1受体抗体阳性率及抗体滴度在大鼠肺心病模型中明显增高,表明肺心病的发生发展与M2和β1受体的自身抗体密切相关。  相似文献   
49.
目的:观察大剂量静脉滴注免疫球蛋白(HD-IVIG)治疗重型格林-巴利综合征(GBS)的疗效.方法:选择确诊为重型GBS的病例13例,于首次发病后2周内给予HD-IVIG治疗,剂量为0.4g*kg-1*d-1,连续5天为一疗程.治疗前后采用神经功能缺损评分法进行疗效评价.结果:13例GBS患者治疗前后神经功能缺损评分分别为4.23±0.44与2.54±1.45,治疗后比治疗前降低1.69±1.18,差异有显著性(P<0.01),同时治疗前后有很高的相关性(P<0.01).结论:HD-IVIG 治疗重型GBS疗效出现早,人工辅助通气时间短,可作为治疗重型GBS的首选方法.  相似文献   
50.
目的 探讨军人花粉症治疗的有效方法。方法 采用提高起始浓度和快速递增浓度 ,上臂外侧皮下注射的方法对 10 6位军人花粉症患者行快速免疫治疗 ,并对每一位患者治疗前后检测血清中总IgE和嗜酸细胞阳离子蛋白 (ECP)。 结果 治疗前后患者总IgE和ECP值有显著性差异。 10 6例患者经 1~ 3年随访复查 ,78例 2个以上发病季节未发作 ,或仅有轻微鼻痒、眼痒 ,18例症状减轻 ,发病时间缩短半月 ,10例症状无明显改善。显效 82例 ,有效 14例 ,无效 10例 ,总有效率为 90 .5 7%。结论 快速免疫治疗能使患者血清总IgE和ECP下降 ,对军人花粉症疗效好。  相似文献   
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