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排序方式: 共有726条查询结果,搜索用时 0 毫秒
1.
梅毒螺旋体外膜蛋白Gpd的基因型分析及其重组蛋白的免疫原性鉴定 总被引:2,自引:0,他引:2
目的 构建梅毒螺旋体 (Treponemapallidum ,Tp)外膜蛋白Gpd基因的原核表达载体 ,检测其表达产物的免疫原性 ,并比较梅毒螺旋体各菌株Gpd基因序列的同源度。方法 从TpNichols株基因组模板中PCR扩增Gpd基因 ,与GenBank登录的序列做blast比较 ,定向克隆构建原核表达重组体pET2 8b( + ) -Gpd ,转入大肠杆菌ril表达菌 ,SDS -PAGE分析重组蛋白的表达 ,Western -blot检测重组蛋白的免疫原性。结果 载体上所连目的基因片段序列与GenBank登录的Nichols株Gpd基因序列完全一致 ,同其他病原性密螺旋体菌株登陆序列比较同源度为 98%~ 1 0 0 %。SDS -PAGE检测诱导产物显示有一Mr约为 41kDa的特异蛋白带 ,免疫印迹技术检测其能与梅毒阳性标准血清反应。结论 Tp原核表达重组体pET2 8b( + ) -Gpd成功构建 ,且能够在ril表达菌中融合表达 ,为进一步研究该蛋白的生物学功能奠定了一定的实验基础。 相似文献
2.
Post-operative progress of dystonia patients following globus pallidus internus deep brain stimulation 总被引:1,自引:0,他引:1
J. Yianni P. G. Bain R. P. Gregory D. Nandi C. Joint R. B. Scott J. F. Stein T. Z. Aziz 《European journal of neurology》2003,10(3):239-247
In the current era of functional surgery for movement disorders, deep brain stimulation (DBS) of the globus pallidus internus (GPi) is emerging as the favoured intervention for patients with dystonia. Here we report our results in 20 patients with medically intractable dystonia treated with GPi stimulation. The series comprised 14 patients with generalized dystonia and six with spasmodic torticollis. Although comparisons were limited by differences in their respective neurological rating scales, chronic DBS clearly benefited both patient groups. Data conveying the rate of change in neurological function following intervention are also presented, demonstrating the gradual but progressive and sustained nature of improvement following stimulation of the GPi in dystonic patients. 相似文献
3.
Specific and sensitive diagnosis of syphilis using a real-time PCR for Treponema pallidum 总被引:1,自引:0,他引:1
A. G. Koek S. M. Bruisten M. Dierdorp A. P. van Dam K. Templeton 《Clinical microbiology and infection》2006,12(12):1233-1236
A real-time PCR assay with a Taqman probe was developed that targeted the polA gene of Treponema pallidum. The test was validated using an analytical panel (n = 140) and a clinical panel of genital samples (n = 112) from patients attending a sexually transmitted infections clinic. High sensitivities and specificities of 94-100% were achieved using two real-time PCR platforms, the Rotor-Gene and the iCycler. The assay can be completed within 2 h, enabling reporting in <8 h. This fast and robust assay is suitable for implementation in routine laboratories for diagnosing primary syphilis. 相似文献
4.
The nucleus accumbens and ventral pallidum receive dopamine (DA) projections from the mesencephalon. Although DA inputs to the nucleus accumbens are implicated in both locomotion and reward processes, little is known of the behavioural significance of DA in the ventral pallidum. These studies examined the effects of
-amphetamine injected into the nucleus accumbens or ventral pallidum on locomotor activity and responding for a conditioned reward (CR). In the nucleus accumbens
-amphetamine dose dependently (1, 3 and 10 μg) increased locomotion within 5–10 min of injection. Intra-ventral pallidum microinjections of
-amphetamine also increased activity in this dose range, but the effect occurred with a longer latency (5–20 min). The magnitude of the response evoked by ventral pallidum injections was lower than that evoked by nucleus accumbens injections. The GABAA antagonist picrotoxin (0.1 μg) stimulated activity when injected into the ventral pallidum but not the nucleus accumbens, providing a pharmacological dissociation between the two injection sites. In the CR studies,
-amphetamine injected into both sites potentiated responding for a CR previously paired with food delivery, without altering responding on an inactive lever. Picrotoxin injected into the ventral pallidum reduced responding and abolished the selectivity of responding for CR. The results show that DA release in the ventral pallidum enhances locomotion and responding for a CR, providing evidence that DA in the ventral pallidum plays a significant role in the mediation of the effects of
-amphetamine. The failure of picrotoxin to elevate responding for CR despite increasing locomotor activity indicates that pharmacologically-induced blockade of GABAA receptors in the ventral pallidum disrupts goal-directed responding. 相似文献
5.
6.
Kretschmer BD 《Brain research》2000,859(1):64-156
The ventral pallidum is the output structure of the nucleus accumbens in the ventral corticostriato-thalamocortical loop. Information processing in this loop is critically involved in motor behavior and reinforcement. The ventral pallidum receives a direct dopaminergic input from the ventral tegmental area, but also glutamatergic input from cortical and limbic areas. It has been assumed that dopamine release in the VP is indeed modulated by glutamate. The present study investigated the effects of NMDA receptor blockade on motor behavior and dopamine release in the ventral pallidum. In a first experiment, rats were implanted with microdialysis probes in the ventral pallidum and were systemically injected or locally perfused via the microdialysis probe with dizocilpine (0.32 mg/kg, 10 and 100 microM, respectively). Effects on dopamine and on locomotion were simultaneously monitored. In a second experiment, ventral pallidum was lesioned by quinolinic acid and the effects of systemic dizocilpine (0.08 and 0.16 mg/kg) on locomotion and stereotyped sniffing behavior were determined. It was found that systemic and local dizocilpine administration increased dopamine release in the ventral pallidum to a similar extent whereas only systemic treatment was accompanied by locomotor stimulation. Lesion of the ventral pallidum did not affect locomotion and stereotyped sniffing behavior induced by systemic dizocilpine treatment. Thus, DA release in the ventral pallidum that is elevated by blockade of NMDA receptors is not relevant for activation of motor behavior. 相似文献
7.
梅毒是由梅毒螺旋体进入循环系统进行血行播散导致的多系统损害,但目前其全身播散的具体机制尚未完全明确.基于国内外的研究进展,本文从梅毒螺旋体黏附与细胞外基质降解、细胞间连接和细胞骨架系统破坏、血管生成、炎症细胞浸润等多方面探讨梅毒螺旋体血行播散的机制,为进一步研究提供理论基础. 相似文献
8.
目的 分别从梅毒螺旋体(Treponema pallidum,Tp)临床菌株和尖锐湿疣(cA)组织中扩增人乳头瘤病毒(HPV)6b型L1和TpN15基因,构建HPV6b L1-TpN15嵌合基因及其原核表达系统.方法 采用PCR分别从CA组织及Tp临床菌株中扩增HPV6b L1和TpN15基因片段,构建HPV6b L1-TpN15嵌合基因,将其克隆入原核表达载体pET32a(+)构建重组质粒pET32a(+)/HPV6b L1-TpN15,经测序鉴定后转化大肠杆菌BL21 (DE3),经异丙基硫代-β-D-半乳糖苷(IPTG)诱导后表达的融合蛋白用十二烷基磺酸钠(SDS)-聚丙烯酰胺凝胶电泳(PAGE)、蛋白质印迹法分析鉴定.结果 HPV6b L1-TpN15融合蛋白在原核表达系统中得到了较高表达.结论 原核表达的HPV6bL1-TpN15融合蛋白具较强的抗原性. 相似文献
9.
为探讨海藻多糖抗氧化活性及抗衰老作用,体外测定昆布多糖,羊栖菜多糖,海蒿子多糖对羟基自由基,超氧自由基及其DPPH自由基的清除作用;采用秀丽隐杆线虫为研究模型,在培养基中添加不同浓度的海藻多糖,每日定时观察并记录线虫存活数,计算平均存活率。结果表明海藻多糖具有抗氧化能力,其中1.2mg/mL的昆布多糖羟基自由基清除能力最强,达到92.10%;海蒿子多糖DPPH自由基的清除能力最强,当浓度达到1.2mg/mL时,清除率为59.55%;1mg/mL海蒿子多糖超氧自由基的清除率达15.66%。秀丽隐杆线虫寿命实验表明,不同的海藻多糖均能延长线虫的寿命,且在实验浓度下,多糖浓度越高寿命延长越明显。研究结果表明所选海藻多糖具有显著的体外抗氧化活性,动物实验表明海藻多糖具有抗衰老作用,能显著延长线虫寿命。该结果为海藻多糖应用于医药、保健品领域的开发提供了一定的实验基础。 相似文献
10.
Paolo Turchetti Fernanda Pacella Elena Pacella Concetta Mirisola Ilaria Uccella 《European journal of medical research》2012,17(1):3
Unilateral papillitis caused by Treponema pallidum was found in an immunocompetent homosexual patient with severe vision loss who had received previous antibiotics treatment. Syphilis-related ocular manifestation is more common in the early stages of the disease and it can be associated with a central nervous system localization. In this patient, neurosyphilis was diagnosed on the basis of clinical and laboratory findings. Optical examination revealed unilateral papillitis in the left eye and no relative afferent pupillary defects. The patient underwent visual field examinations with conventional perimetry using the 30-2 program of the Humphrey Visual Field Analyzer, which indicated a blind spot enlargement in the left eye. Optical coherence tomography, visual evoked potentials (VEP), and fluorescein angiograms revealed inflammation of the optic nerve head with edematous and blurred margins. A reactive T. pallidum hemagglutination assay with low rapid plasma reagin (RPR) serum titer was performed; an HIV antibody test and MRI of the orbits and head with contrast gave negative results. Resolution of the ocular inflammation after intravenous penicillin treatment was obtained. The reported case illustrates the importance of early recognition of this treatable disease. The rise of syphilis, especially in urban areas, necessitates a high level of suspicion when dealing with patients with intraocular inflammation of unknown origin. Lues serology should be incorporated into routine laboratory diagnostics to aid in the detection of such cases. Considering the re-emergence of syphilis, screening of migrants from countries with high syphilis seroprevalences should be recommended. 相似文献