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41.
Dental implants for orthodontic anchorage   总被引:7,自引:0,他引:7  
The purpose of this article is to review and update current concepts involving the use of dental implants for orthodontic anchorage. Topics to be discussed include indications, implant requirements (eg, materials, size, designs of dental implants), surgery and healing time, biomechanics and forces, loading time, implant maintenance, posttreatment considerations, and disadvantages.  相似文献   
42.
目的 介绍自行研制的带控制阀种植牙手术骨粉收集器,并观察其临床应用效果.方法 选取2008年5月至2009年10月38例牙种植患者,应用自制的骨粉收集器收集种植窝制备时产生的骨碎屑,并将其用于修复种植体周围骨缺损,其中开窗式骨缺损29处,唇颊(舌)侧种植体颈部角形缺损23处.结果 所有病例术后均无创口感染及裂开,原缺损处局部形态饱满,牙龈无明显退缩,X线片示种植体与周围牙槽骨形成良好的骨结合.结论 应用自制骨粉收集器收集的骨粉修复种植体周围小型骨缺损效果良好,使用方便,具有良好的应用前景.
Abstract:
Objective To introduce a self-developed bone collector designed by the authors and evaluate its effect in clinical application. Methods A self-developed bone collector was used in 38 patients who underwent the dental implant operation from May 2008 to October 2009. During the operation the bone particles were harvested, which was used for the reconstruction of the bone defects around the implant simultaneously. The defects were fenestrate in 29 regions and triangle in 23 regions on buccal or lingual side of the dental implants. Results All cases had no surgical wound infection and dehiscence 7-10 days after operation. Three to six months after implantation, the X-ray showed that all the dental implants had perfect osseointergration and the alveolar bone were successfully augmented. Conclusions Bone debris harvested by self-developed bone collector could repair small peri-implant bone defects, which is simple to use in clinic.  相似文献   
43.
Over a 10-year period (1982–1991), a total of 150 patients divided into two groups with varying degrees of oral submucous fibrosis (OSF) were treated by either medical or surgical therapies. Medical treatment involved (a) conservative oral administration of vitamin B-complex, buflomedial hydrochloride and topical triamcinolone acetonide 0.1%, or (b) conventional submucosal injections of a combination of dexamethasone and hyaluronidase, or (c) a combination of both (a) and (b). The surgical group was treated by the excision of fibrotic tissues and covering the defect with split-thickness skin, fresh human amnion, or buccal fat pad (BFP) grafts. Treatment was chosen according to the stage of clinical progression to gain maximal interincisal distance (ID). The cases were followed up by monthly examinations for at least two years, or when possible even longer. A combination of (a) and (b) medical treatment was satisfactory in cases of mild impairment (ID > 20 mm) but in the long term it led to symptomatic relief only. Surgical therapy, on the other hand, when accepted by the patients, led to a significant improvement of trismus in cases of severe limitation (ID < 20 mm). Following this strategy, an additional ID increase was observed in all patients. BFP grafting was particularly successful in diminishing scarring after two years as compared with the other two grafts. Together with a cessation of the betel quid chewing habit before and after therapy, these treatment regimens combined with daily mouth opening exercises were found to be necessary to manage OSF cases in early and advanced stages of progression.  相似文献   
44.
The diagnosis of squamous cell carcinoma (SCC) of the tongue metastasising to the lingual lymph nodes is rare. Until now lingual lymph nodes have not been mentioned in any system of lymph node classification. We report a case of SCC of the tongue with metastases to the lymph nodes in the superficial floor of the mouth, and to levels I and II lymph nodes. We provide evidence of the existence of lingual lymph nodes, and validate the practice of removing the lymph node-bearing-tissue of the floor of the mouth during neck dissection in cancers of the oral cavity.  相似文献   
45.
A custom mandibular distraction device for the rat   总被引:1,自引:0,他引:1  
In the last several years, the rat model has been used as a reliable means of studying distraction osteogenesis (DO). This model has several benefits, including lower cost, the availability of molecular reagents for the rat, and the ability to perform a large number of operations in a short time. We have recently developed an external device that is custom-made for the rat mandible and secured at the mandibular ramus. The device consists of a Leone (Florence, Italy) jackscrew distraction assembly (0.2 mm per one-quarter turn), 2 Luhr L-shaped 0.8-mm five-hole microplates, and four 0.8-mm x 3-mm microscrews (Stryker-Leibinger Corp., Kalamazoo, MI) for fixation. Additionally, there is a methylmethacrylate block that is placed on the lingual surface of the angle of the mandible to support the posterior screws. Sterile surgical technique was used, and the same two surgeons performed all operations. To date, we have operated on 153 Sprague-Dawley rats. The procedure has been well tolerated by the animals. We had 17 postoperative deaths (11% mortality), largely as a result of anesthetic complications. There were no wound infections or dehiscence. A mandible fracture was noted in 6 rats (4%), which occurred at the time of device placement. There were no device dislodgments. Postmortem examination showed the device to be well positioned in all rats, with good callous formation at the distraction site. The rats surpassed their preoperative weight after an average of 9.2 days. These results compare favorably with those of other models currently in use. We have developed a device that is currently being used in the study of DO in the rat mandible. Our device is small in size, does not require wide undermining for its placement, and has had a low incidence of device dislodgment or infection. This model has shown great reproducibility and thus should be effective in its application for the histologic and biochemical investigation of DO in the rat.  相似文献   
46.
计算机网络(computer network)作为计算机技术和通信技术相结合的产物,它通过通信设备和线路将不同地理位置上的具有独立功能的计算机互连起来,在功能完备的网络软件支持下,实现资源共享和信息交换。1972年以太网的开发实现了真正意义上的计算机网络,从此各种局域网、广域网相继出现,迅速发展。  相似文献   
47.
外周血VEGF表达水平与舌癌颈淋巴结转移关系的临床研究   总被引:3,自引:0,他引:3  
目的 :探讨外周血VEGF表达水平与舌癌转移之间的关系以及临床意义。方法 :对舌癌患者外周血VEGF的表达水平进行ELISA检测 ,并对患者术后所有颈部淋巴结进行HE染色。结果 :转移组患者血清VEGF浓度为 ( 5 0 8.2 8± 14 .193 3 ) pg/ml ,无转移组患者血清VEGF浓度为 ( 13 0 .49± 6.2 5 41) pg/ml ,二者存在显著差异 (P <0 .0 1)。转移组患者术后血清VEGF浓度显著下降 ,为 ( 14 1.79± 5 .2 2 41) pg/ml,与术前存在显著差异 (P <0 .0 1)。结论 :舌癌患者血清VEGF浓度与颈淋巴结转移的发生有显著相关性 ,可以作为颈淋巴结转移的预测指标之一  相似文献   
48.
The purpose of this study was to investigate the variation in corrosion resistance of commercial stainless steel (SS) brackets with different brands and types for the same application, using the electrochemical technique. The linear polarization test was used to evaluate the corrosion resistance, in terms of polarization resistance (Rp), of as-received commercial SS brackets in acidic artificial saliva. A two-way analysis of variance was used to analyze the Rp with the factors of brand and type. A scanning electron microscope and an atomic force microscope were used to analyze the surface morphology and roughness, respectively. The X-ray photoelectron spectroscopy was used to identify the chemical composition of the passive film on SS brackets. Results showed that different brands of SS brackets had a statistically significant difference in Rp (P < .0001), whereas there was no statistical difference between the bracket types ("Roth" and standard) (P = .27). Different surface topography, including surface roughness and defect, was present among the tested SS brackets. The same passive film structure, containing Cr2O3/Fe2O3 with small amounts of NiO, was observed on all SS brackets. The surface topography of the commercial SS brackets with identical surface passive film structure did not correspond with the difference in corrosion resistance.  相似文献   
49.
Some patients who have heterotrophic ossification (HO) in a postburn scar are occasionally seen in the clinic. The occurrence of HO following hip and abdominal surgery is common in males, whereas females are frequently affected following burns. The HO of skin grafts in burn scars of the superior body parts is uncommon, especially on the face. We report a recent case of a male patient in whom HO arose on skin grafts on his chin. The patient presented with a history of a painless chin mass for 48 years. Computed tomography scan suggested that the mass was located within subcutaneous tissue away from the lower jaw. The density of the mass was almost the same as the cortical bone of the lower jaw. The mass was completely resected under general anesthesia. It was a rectangular mass of 3× 0.5× 0.3 cm. Histological examination gave the diagnosis of HO, which was also confirmed by immunohistochemical stainings for vimentin. Recurrence was not found in this case by clinical and radiologic follow-up at 1 year after surgery.  相似文献   
50.
目的:探讨白细胞介素1受体拮抗剂(interleukin-1 receptor antagonist,IL-1ra)基因型与2型糖尿患者群中牙周炎(periodontitis of diabetes mellitus,DMP)易感性的关系。方法:收集2型糖尿病患者186例,分为糖尿病伴牙周炎组108名和糖尿病不伴牙周炎组78名,取血提取DNA,采用序列特异引物多聚酶链反应(sequence specific primers polymerase chain reaction,SSP-PCR)法测定IL-1RN内含子2/VNTR位点的基因型,比较各基因型检出率的差别。结果:IL-1RN内含子2/VNTR等位基因A2在2型糖尿病伴牙周炎组的检出率显著高于2型糖尿病不伴牙周炎组,分布差异有显著性(χ2=3.579,P=0.040)。结论:在2型糖尿病患者中,IL-1RN内含子2/VNTR等位基因A2可能与牙周炎的遗传易感性相关。  相似文献   
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