全文获取类型
收费全文 | 21402篇 |
免费 | 1324篇 |
国内免费 | 1454篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 222篇 |
妇产科学 | 66篇 |
基础医学 | 2676篇 |
口腔科学 | 60篇 |
临床医学 | 2750篇 |
内科学 | 610篇 |
皮肤病学 | 26篇 |
神经病学 | 6888篇 |
特种医学 | 803篇 |
外国民族医学 | 1篇 |
外科学 | 4811篇 |
综合类 | 3032篇 |
现状与发展 | 3篇 |
预防医学 | 327篇 |
眼科学 | 18篇 |
药学 | 1119篇 |
10篇 | |
中国医学 | 365篇 |
肿瘤学 | 369篇 |
出版年
2024年 | 50篇 |
2023年 | 301篇 |
2022年 | 437篇 |
2021年 | 640篇 |
2020年 | 639篇 |
2019年 | 555篇 |
2018年 | 560篇 |
2017年 | 628篇 |
2016年 | 625篇 |
2015年 | 660篇 |
2014年 | 1117篇 |
2013年 | 1423篇 |
2012年 | 993篇 |
2011年 | 1078篇 |
2010年 | 1027篇 |
2009年 | 974篇 |
2008年 | 1019篇 |
2007年 | 1123篇 |
2006年 | 1046篇 |
2005年 | 858篇 |
2004年 | 764篇 |
2003年 | 791篇 |
2002年 | 668篇 |
2001年 | 539篇 |
2000年 | 433篇 |
1999年 | 406篇 |
1998年 | 458篇 |
1997年 | 412篇 |
1996年 | 357篇 |
1995年 | 297篇 |
1994年 | 281篇 |
1993年 | 242篇 |
1992年 | 243篇 |
1991年 | 214篇 |
1990年 | 205篇 |
1989年 | 207篇 |
1988年 | 159篇 |
1987年 | 138篇 |
1986年 | 199篇 |
1985年 | 303篇 |
1984年 | 264篇 |
1983年 | 216篇 |
1982年 | 164篇 |
1981年 | 147篇 |
1980年 | 151篇 |
1979年 | 40篇 |
1978年 | 44篇 |
1977年 | 30篇 |
1976年 | 19篇 |
1973年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
61.
SK&F 86466, 6-chloro-3-methyl-2,3,4,5-tetrahydro-1-H-3-benzazepine, is a potent and selective antagonist of the α2-adrenoceptor in vitro. This compound produced a small pressor response accompanied by a marked bradycardia when administered i.v. to the pithed normotensive rat. The pressor response was not affected by reserpine treatment, pretreatment with α- or β-adrenoceptor antagonists, atropine, or hexamethonium. The bradycardia was markedly reduced by bilateral vagotomy and pretreatment with atropine and attenuated by hexamethonium. The negative chronotropic action of SK&F 86466 was abolished by a combination of vagotomy and atropine. Mediation of the bradycardia by a baroreceptor reflex was ruled out by the observations that a lack of change in heart rate was associated with the vasopressor response to phenylephrine in the pithed rat pretreated with propranolol. It is concluded that the negative chronotropic action of SK&F 86466 in the pithed rat is mediated indirectly by activation of the cholinergic innervation of the heart. 相似文献
62.
63.
Sofia I. Andrikoula Haris S. Vasiliadis Anastasios V. Tokis Paraskevi Kosta Anna Batistatou Anastasios D. Georgoulis 《Arthroscopy》2007
Intra-articular ganglia are rare and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. We present 4 cases of intra-articular ganglion cysts associated with the anterior cruciate ligament (ACL) in 3 patients. The most commonly occurring symptoms were pain aggravated after stressing activities and limited knee range of motion. In 1 patient, ganglion cysts appeared in both knees with a time difference of 1 year. An MRI revealed typical signs of ganglion cysts in the substance of the ACL. Arthroscopy was performed for further evaluation and treatment. Histologic examination of the tissue removed revealed the presence of features consistent with ganglion cysts. Therefore, in the case of chronic knee discomfort with nonspecific clinical signs and symptoms and without a clear cause, an intra-articular ganglion cyst should be considered as causing pathology. An MRI is the most sensitive and specific method for diagnosis. However, the relatively slow progression of symptoms may delay the patient’s decision to seek medical attention. Delayed diagnosis makes arthroscopic total resection of the ganglion technically demanding or not possible at all, and extensive debridement of the ACL may be required. 相似文献
64.
目的总结多发性硬化(MS)患者的临床特点(精神情感障碍)以及脑脊液、诱发电位、影像学改变进行分析。方法回顾分析65例MS患者的有关临床和实验室资料。结果65例中,男17例,女48例;年龄16~68岁,平均(36.5±14.1)岁,男女比为1∶2.8。MS首发及常见症状为感觉异常、肢体无力、视力减退及括约肌功能障碍,病变部位以脊髓受累最多见,部分患者存在精神情感障碍。结论出现感觉异常有助于MS早期诊断,诱发电位及MRI有助于发现亚临床病变;括约肌功能异常多见,可能与脊髓受累较多有关;MS患者的精神情感应受人们关注。 相似文献
65.
Jocelyn M. Cottrell BS Marjolein C. H. van der Meulen PhD Joseph M. Lane MD Elizabeth R. Myers PhD 《HSS journal》2006,2(1):12-18
The clinical goal of spinal fusion is to reduce motion and the associated pain. Therefore, measuring motion under loading
is critical. The purpose of this study was to validate four-point bending as a means to mechanically evaluate simulated fusions
in dog and rabbit spines. We hypothesized that this method would be more sensitive than manual palpation and would be able
to distinguish unilateral vs bilateral fusion. Spines from four mixed breed dogs and four New Zealand white rabbits were used
to simulate posterolateral fusion with polymethyl methacrylate as the fusion mass. We performed manual palpation and nondestructive
mechanical testing in four-point bending in four planes of motion: flexion, extension, and right and left bending. This testing
protocol was used for each specimen in three fusion modes: intact, unilateral, and bilateral fusion. Under manual palpation,
all intact spines were rated as not fused, and all unilateral and bilateral simulated fusions were rated as fused. In four-point
bending, dog spines were significantly stiffer after unilateral fusion compared with intact in all directions. Additionally,
rabbit spines were stiffer in flexion and left bending after unilateral fusion. All specimens exhibited significant differences
between intact and bilateral fusion except the rabbit in extension. For unilateral vs bilateral fusion, significant differences
were present for right bending in the dog model and for flexion in the rabbit. Unilateral fusion can provide enough stability
to constitute a fused grade by manual palpation but may not provide structural stiffness comparable to bilateral fusion. 相似文献
66.
颈椎病伴椎管狭窄患者再手术问题探讨 总被引:1,自引:0,他引:1
目的:探讨颈椎病伴椎管狭窄患者再手术的原因、手术方式及其相关问题。方法:我院2002年7月~2003年12月对40例颈椎病伴椎管狭窄术后疗效不佳或症状复发的患者进行了后路多节段(5个或以上)减压手术。根据其手术治疗方式及影像学资料分析再手术原因,并进行术后疗效评价。结果:经前路手术者再手术的主要原因为:(1)伴有多节段颈椎管狭窄因素时,只选择部分压迫重的节段行减压融合15例;(2)经前路多节段(≥3个节段)减压融合后,相邻节段继续退变,出现新的脊髓压迫表现及椎间不稳定9例;(3)伴有OPLL时,行部分节段前路减压融合后,病变呈进展表现,产生或加重对脊髓的压迫8例。经后路手术者再手术的原因为:(1)后路减压节段不够5例(包括1例前后路联合手术者);(2)后路减压不充分3例。再手术后随访1.3~2.7年,平均2.1年,所有患者脊髓功能获得一定的提高,JOA评分改善率为51.3%。结论:颈椎病伴椎管狭窄病例再手术的主要原因为椎管狭窄因素仍然存在,经后路多节段(5个或以上)减压手术治疗可彻底去除颈椎管狭窄因素,有效解除脊髓前、后方所受的压迫,可获得较满意的临床疗效。 相似文献
67.
胸腰椎骨折术后内固定松动、断裂的原因及预防 总被引:14,自引:3,他引:11
目的 探讨椎弓根螺钉系统用于胸腰椎骨折术后出现松动、断裂的原因,并提出相应的预防对策。方法 12例胸腰椎骨折术后内固定失效病例,采用RF系统3例,AF系统9例。均未行植骨融合,AF系统中未按要求安装横连结3例,术后伤椎前缘高度平均恢复至正常的85.2%。结果 术后8—21个月出现棒断裂4例,螺钉断裂3例,钉帽松动5例。结论 内固定物的自身问题、术者的经验欠缺及操作不规范是胸腰椎骨折术后椎弓根螺钉系统松动、断裂的原因,但伤椎骨结构未能得到良好重建及术后椎间盘退变可能是其更重要的因素。因此重视内固定物的选择、加强规范操作,强调对损伤椎体及椎间盘的全面处理是预防内固定失效的有效措施。 相似文献
68.
脊髓血管母细胞瘤的显微手术治疗(附11例分析) 总被引:2,自引:0,他引:2
目的探讨脊髓血管母细胞瘤的临床特点和外科治疗技巧。方法回顾性分析11例脊髓髓内血管母细胞瘤的诊治经验。本组临床表现主要为感觉和运动障碍、肌肉萎缩及大小便失禁。均经后正中入路切除肿瘤,术中及术后常规使用甲基强的松龙。结果肿瘤均获全切除。术后短时间内症状改善8例,无变化2例,加重1例,无手术死亡。结论本病根据术前典型的影像资料均可确诊。术中尽可能避免活检或分块切除肿瘤,以免引起难以控制的出血和盲目止血引起的脊髓损害。大剂量甲基强的松龙可减轻脊髓水肿。 相似文献
69.
目的 比较大脑皮质向脊髓与红核发出投射的区域并探讨是否有分支投射存在。方法 将。TB及NY分别注入大白鼠的脊髓与红核内,在大脑皮质观察比较标记细胞出现的部位。结果 FB标记细胞出现在24,10,8,6,4,3,1,2,23,29b,29c,18,7,13,39区。NY标记细胞出现于6,4,3,1区,10区的尾侧部及7,18区的颅饲部亦有少量存在。无发现双标记细胞。结论 大脑皮质向脊髓发出投射的区域非常广泛,向红核发出投射的区域全部重叠于皮质脊髓神经元分布的区域内,皮质脊髓神经元无分支投射到红核。 相似文献
70.
Objective. Neurally augmented sexual function (NASF) is the production of pleasurable genital stimulation and subsequent orgasm through the application of electrical energy to provide stimulation of the spinal cord or peripheral nerves. The purpose of this paper is to demonstrate the reproducibility of this phenomenon. Materials and Methods. Eleven otherwise healthy women, ages 32–60 years, were selected for this study. Through standard techniques, quadripolar (octopolar in the final patient) leads were placed in the epidural space percutaneuously. The lead was maneuvered initially to an L1–L2 position and then repositioned based on feedback from the patient. The patients were allowed to utilize the device ad libitum for up to 9 days. Results. Successful stimulation was achieved in 91% (10/11) of patients. These women described a greater frequency in sexual activity, increased lubrication, and overall satisfaction. A smaller subset had substantial improvement in sexual function as measured by orgasmic capacity. This subset consisted of women with secondary anorgasmia. A return of orgasmic capacity was found in 80% (4/5) of patients having secondary anorgasmia with an average intensity of ≥ 3/5 while using the device. Once the device was removed, the patients returned to their previous anorgasmic status. Conclusions. Pleasurable genital stimulation of the spinal cord is a consistently reproducible phenomenon. In a subset of the population studied, improvement in orgasmic function was noted. This was noted in the group with secondary orgasmic dysfunction. 相似文献