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991.
目的探讨LigaSure在腹腔镜胃癌根治术中的应用价值。方法2001年7月~2007年7月,应用LigaSure行腹腔镜胃癌根治性切除术71例,按TNM分期,Ⅰ期15例,Ⅱ期33例,Ⅲa期23例。行根治性全胃切除术27例,根治性远侧胃大部切除术39例,根治性近侧胃大部切除术5例。采用腹腔镜辅助手术方法:以脐孔,左、右锁骨中线肋缘下,脐与剑突连线上、中1/3交界点为手术操作孔,术中扩大剑突下操作孔3~5cm为辅助切口。术中均采用LigaSure分离、处理血管,直接凝固切断包含直径达7mm血管的网膜及胃周血管;胃癌淋巴结清扫时,联合应用超声刀裸化血管,再用LigaSure钳夹凝固后,于闭合带远端剪断血管,完成腹腔镜下D2胃癌根治手术。结果71例均手术成功,无中转开腹,术中出血少,无术中、术后严重并发症发生,术后近期肺部感染3例、应激性溃疡出血1例、十二指肠残端漏1例(保守治愈)。LigaSure闭合胃周血管良好,未使用钛夹或腔镜专用切割吻合器(Endo—GIA)。71例随访4~72个月,平均38.6月,死亡11例(其中9例因肿瘤转移),远处转移10例,复发14例,2例术后远期吻合口狭窄。结论LigaSure行腹腔镜胃癌根治术安全、可靠,是腹腔镜手术理想的切割止血工具。  相似文献   
992.

Background  

Within cluster randomized trials no algorithms exist to generate a full enumeration of a block randomization, balancing for covariates across treatment arms. Furthermore, often for practical reasons multiple blocks are required to fully randomize a study, which may not have been well balanced within blocks.  相似文献   
993.
Safety evaluation of surgical materials by cytotoxicity testing   总被引:2,自引:1,他引:1  
The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo use of biomaterials on surrounding cells, tissues, and organs.  相似文献   
994.
INTRODUCTION: Spinal cord compression due to meningeal thickening is a rare occurrence in shunted patients. Because of the long delay to clinical onset, this complication has not been identified as yet. AIMS: We report on nine cases of shunt-related progressive myelopathy due to meningeal thickening (SPMMT). MATERIALS AND METHODS: We reviewed our database of shunted children, for cases having developed progressive tetraparesis due to cervical meningeal thickening. RESULTS: We identified nine observations of SPMMT, eight of these with hydrocephalus due to neonatal meningitis; the last case had Dandy-Walker malformation shunted at birth and suffered postoperative meningitis. The age of clinical onset of myelopathy was between 6 and 20 years (median 12.8). All patients presented with slowly progressive walking difficulties with falls and no spinal pain. Magnetic resonance imaging (MRI) showed typically a thickened dura mater with collapse of the arachnoid space, compensatory expansion of the epidural fat, and T2 hyperintensity in the spinal cord. We operated on seven patients for surgical decompression and arachnoidolysis: One died postoperatively because of shunt malfunction, and two others died later of complications of tetraplegia. Three patients were aggravated after surgery, three experienced partial improvement, but one of these subsequently deteriorated again. CONCLUSION: SPMMT appears to be a novel and well-defined clinical and pathological entity; its pathological and radiological features are stereotyped; however, the diagnosis is delayed because of the slow pace of the disease. Although surgical decompression may be the only option, its results were poor in our experience; earlier surgery might improve this grim prognosis.  相似文献   
995.
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography (HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility, and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology.  相似文献   
996.
Laparoscopic Nissen fundoplication (LNF) has become the most commonly performed antireflux procedure since its introduction in 1991. There are few studies with greater than 5-year outcomes. Herein we report a series of 312 consecutive patients who underwent primary LNF before 1996. Follow-up of more than 6 years was available in 166 patients, and the mean follow-up was 11 years (median 11.1 years, range 6.1–13.3 years). Prospective data collection included preoperative and current symptom scores (scale 0 = none to 3 = severe), as well as the level of patient satisfaction and use of antireflux medications. Total symptom score for each patient was summed from seven symptoms for a maximum value of 21. Heartburn and regurgitation were the most improved symptoms; however, all symptoms were significantly improved (P < 0.01). The total symptom score at follow-up was 2.6 down from 7.5 at baseline, with a mean difference of −4.9 (range −12 to 3). The percentage of patients stating they would have the procedure again was 93.3%, and 70% were off daily antireflux medications. Outcomes at a mean of 11 years after LNF are excellent, and the majority of patients had their symptoms resolved or significantly improved and are satisfied with their results. Presented at the 47th Annual Meeting of the Society for Surgery of the Alimentary Tract, May 22, 2006, Los Angeles, CA  相似文献   
997.
Background In the era of Helicobacter pylori treatment, the role of vagotomy in bleeding duodenal ulcers is debatable. National outcomes were evaluated to determine the current surgical treatment and use of vagotomy for bleeding duodenal ulcers. Methods Data from the Nationwide Inpatient Sample (NIS) were used from years 1999 to 2003. Patients were selected using diagnostic codes for acute duodenal ulcer bleed and procedure codes for simple oversew of a bleeding ulcer and vagotomy. Data were analyzed using multiple linear and logistic regression. Results Between 1999 and 2003, 100,931 patients with an acute bleeding duodenal ulcer were identified. Over time, there was a decrease in the number of acute bleeding ulcers (p = 0.027) and a decrease in the number of vagotomies (p = 0.027). A high co-morbidity index [odds ratio (OR), 0.60, p = 0.017], operation in the Midwest (OR 0.50, p < 0.001) and operation in the West (OR 0.68, p = 0.034) were predictive of no vagotomy during surgery for a bleeding duodenal ulcer. Conclusions A vagotomy is not commonly performed during surgical treatment of an acute bleeding duodenal ulcer. This variation in practice was not fully explained by patient characteristics. We must seek new evidence to determine the safety of combined medical and surgical management of this clinical problem. Presented at DDW/SSAT May 20–24, Los Angeles, California.  相似文献   
998.

Background  

The optimal management of chronic ruptures of the Achilles tendon is surgical reconstruction. Reconstruction of the Achilles tendon using peroneus brevis has been widely reported. Classically, these procedures involve relatively long surgical wounds in a relatively hypovascular area which is susceptible to wound breakdown.  相似文献   
999.
目的 研究慢性"炎症性"肺动脉高压大鼠在肺动脉高压形成过程中肺动脉蛋白激酶C(PKC)亚型的表达.方法 建立野百合碱诱导的慢性"炎症性"肺动脉高压大鼠模型,应用Western blot技术检测肺动脉高压形成过程中大鼠肺动脉四种PKC亚型(PKCα、PKCβⅡ、PKCδ和PKCε)的表达变化.结果 PKCα、PKCβⅡ和PKCδ亚型在正常和肺动脉高压大鼠肺动脉中均有表达,而PKCε亚型未检测到.在肺动脉高压形成过程中,大鼠肺动脉胞浆和胞膜组分表达的PKCα均逐渐上升,到第14天达到高峰后略有下降,且胞膜表达量的升高远比胞浆明显.胞浆PKCβⅡ和PKCδ表达量均在第8天达最高,而胞膜中二者均表现出持续升高的趋势.结论 PKCα、PKCβⅡ和PKCδ亚型可能参与了慢性"炎症性"肺动脉高压的形成,其表达变化可能与其转位有关.  相似文献   
1000.
We describe an arthroscopic approach of tarsometatarsal arthrodesis for post-traumatic arthritis. Five tarsometatarsal portals (medial, P1–2, P2–3, P3–4, P4–5) are identified at the junctional points between the metatarsals by means of image intensifier. The first metatarsocuneiform joint is approached through the medial and P1–2 portal. Articular cartilage is denuded and micro-fracture of subchondral bone is performed with an arthroscopic awl. The second metatarsocuneiform joint is approached through the P1–2 and P2–3 portals and the third metatarsocuneiform joint is approached through the P2–3 and P3–4 portals. The articular surfaces are prepared for arthrodesis. The articulations are kept in desired position and transfixed with 4.0 mm cannulated screws. The fourth and fifth metatarsocuboid articulations are rarely included in the procedure. Arthroscopic arthrodesis or tendon arthroplasty of the lateral column can be performed through the P3–4 and P4–5 portals.  相似文献   
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