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91.
Ectopic cervical or cervico-mediastinal thymomas are very rare and most of them are asymptomatic, except for the presence of a cervical mass. We present the case of a 71-year-old man with an ectopic cervico-mediastinal thymoma threatening superior vena cava syndrome. He had a slight headache and presented with venous dilatation on the chest wall. A computed tomographic scan and magnetic resonance, imaging of the chest demonstrated a mass extending from the right neck to the hilum, that indented the trachea and compressed and displaced the brachiocephalic veins anteriorly. Under a right hemicollar incision and median sternotomy, the mass was resected en bloc together with the thymus. The resected specimen was an encapsulated mass measuring 11×7×4 cm. The pathological diagnosis was type AB, non-invasive thymoma, confirmed by 3-color flow, cytometry of tumor-derived lymphocytes. Flow cytometry using biopsy material may contribute to the preoperative diagnosis of ectopic thymoma.  相似文献   
92.
The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time.  相似文献   
93.
目的 应用彩色多普勒超声仪检测冠状动脉血流储备 (coronaryflowreserve ,CFR) ,初步观察老年糖尿病患者中CFR的变化。方法  2 5例老年糖尿病患者及 2 5例健康志愿者作对照组 ,比较两组的空腹血糖 (FBG)、早餐后 2h血糖 (P2hBG)、糖化血红蛋白A1c (HbA1c)、总胆固醇 (TC)、低密度脂蛋白胆固醇 (LDL C)及甘油三酯(TG)、内皮素 1(ET 1)、静息状态时患者冠状动脉的基础血流速度 (bFV)、潘生丁注射后的最大冠脉血流速度(mFV)及CFR。结果 糖尿病组的FBG、P2hBG、TG及ET 1水平显著高于对照组 [分别为 :(9 1± 3 3)mmol/L与 (5 3± 0 7)mmol/L ;(15 8± 5 0 )mmol/L与 (8 5± 2 4 )mmol/L ;(2 96± 0 5 6 )与 (1 6 9± 0 82 )mmol/L及(15 3 80± 13 5 0 )ng/L与 (76 2 3± 10 78)ng/L ,均P <0 0 1],糖尿病组静息时的基础冠脉血流速度 (bFV)及TC、LDL C水平与对照组比较 ,差异均无显著性意义 (均P >0 0 5 ) ,而潘生丁注射后mFV及CFR (CFR =mFV/bFV)较对照组明显下降 [分别为 (5 8 1± 7 9)cm/s与 (73 5± 9 8)cm/s及 2 31± 0 4 9与 3 5 8± 0 4 6 ,P均 <0 0 1]。结论 老年糖尿病患者冠状动脉血流储备明显下降。  相似文献   
94.
95.
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only.  相似文献   
96.
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging. All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients. The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion, we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter, white matter, and basal ganglia.  相似文献   
97.
98.
The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length.  相似文献   
99.
R啨sum啨   Objectif D啨tecterparcytom啨triedefluxler啨sidumorbideminimal(RMM)chezlesenfantsatteintsdeB LLAet啨valuersasignificationclinique . M啨thodes  5 8enfantsatte  相似文献   
100.
目的:探讨二维及彩色多普勒超声对甲状腺良、恶性结节的诊断及鉴别诊断价值。方法:120例甲状腺结节经二维超声了解其声像图表现,然后用彩色多普勒检查,观察结节内部及周边血流分布情况,并将其分为4级。结果:120例302个甲状腺结节中,良性结节264个,恶性结节38个。二维超声显示:恶性结节以实性低回声为主,内可见砂粒样钙化,边界不清,无声晕及包膜;良性结节以等、高回声及囊性、囊实性结节为主,形态规则,边界清,多有声晕及包膜。彩色多普勒超声显示:恶性结节的血流显示率明显高于良性结节,收缩期最高血流速度及阻力指数总体上高于良性结节,且以Ⅱ、Ⅲ级血流为主。结论:二维及彩色多普勒超声诊断甲状腺良、恶性结节准确率高。具有较大的临床应用价值。  相似文献   
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