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1.
Herpes zoster ophthalmicus (HZO) commonly causes isolated ophthalmoplegic syndromes. Visual loss caused by optic neuritis secondary to HZO can be reversible or irreversible. HZO rarely presents as an orbital apex syndrome, when an association with meningo-encephalitis has been reported. We report a case of orbital apex syndrome secondary to HZO treated with systemic steroids and acyclovir. Our patient suffered no systemic complications and displayed a rapid resolution of optic neuropathy. We discuss this case in the light of previous reports and explore the possible pathogenic mechanisms involved.  相似文献   
2.
定量组织速度成像对右室起搏患者左室收缩运动的研究   总被引:1,自引:0,他引:1  
目的 应用定量组织速度成像 (QTVI)评价右室心尖起搏 (RVAP)VVI型对左心收缩功能的影响。方法 应用GEVivid 7彩色多普勒超声显像仪对 2 0例RVAP患者和 2 0例正常人的心尖四腔切面的室间隔和左室外侧壁速度和位移曲线进行观察 ,测量心电图Q波分别至室间隔和左室外侧壁收缩期峰速度的时间 ,并除以R R间期进行校正。结果 QTVI显示右室起搏器置入者的室间隔与左室外侧壁速度曲线的收缩期S波非同步出现。Q波至室间隔收缩期峰速度的时间短于Q波至左室外侧壁收缩期峰速度的时间 ,两者分别为 ( 0 .12± 0 .0 2 )s和 ( 0 .14± 0 .0 2 )s,P <0 .0 5。结论 右室起搏后早期的左室整体收缩功能虽未见明显下降 ,但QTVI可以发现室间隔与左室壁收缩明显的不协调 ,可作为早期分析左室收缩运动的定量方法。  相似文献   
3.
目的 :探讨右室心内膜永久性起搏电极植入术中 ,心尖部起搏与流入道起搏二者在术中起搏参数比较 ,以及流入道起搏电极植入方法。方法 :选择本院行永久性心脏起搏器安置术的 67例患者为研究对象 ,在右室心尖部起搏电极不易固定或测试起搏参数不理想时 ,改为右室流入道起搏 (12例 )。结果 :①右室心尖部及流入道两种位置起搏阈值、R波振幅、心肌阻抗比较无显著性差异 ;②术后随访 2~ 14个月两组病例均未发生电极脱位、感知异常、膈肌收缩。结论 :①右室流入道起搏与心尖部起搏一样是电极植入的有效部位 ;②右室流入道起搏与心尖部起搏一样心室电极植入技术简单易行  相似文献   
4.
Infracture Technique for the zygomatic body and arch reduction   总被引:2,自引:0,他引:2  
In the Orient, prominent malar regions are considered unaesthetic and the majority of women with a prominent malar want to reduce the zygoma. Various operative procedures such as shaving or chiseling the zygomatic body or the zygomatic arch have been used for reducing malar eminence, but the zygomatic arch cannot be reduced sufficiently by these methods. By combining intraoral shaving of the zygomatic body and a new effect arch infracture technique through a temporopreauricular incision, we have obtained very satisfactory results in 19 cases and notable minimal complications over the last three years.  相似文献   
5.
Summary The effect of the hemicholium-3 analog, DMAE, on endplate currents (EPC) was investigated in the transected cutaneous pectoris muscle of the frog using a conventional two-microelectrode voltage clamp. At a low concentration (5 M), DMAE produced a long-lasting decrease in the rate constant of decay () and an increase in the peak current amplitude (Ip). At higher concentrations (10–100 M), DMAE produced biphasic changes characterized by a transient, marked decrease of and increase of Ip followed by a long-lasting marked increase of and decrease of Ip. When DMAE was removed from the bath recovery from block was asymmetrical in that recovered more quickly than did Ip. Pretreatment with neostigmine or collagenase partially antagonized the initial effects without affecting the steady state effects of DMAE, indicating that the initial effects of DMAE may be, at least in part, due to inhibition of the enzyme acetylcholinesterase. The drug reverses the normal voltage dependence of without altering the single exponential nature of decay of the EPC. The inward EPC was more markedly blocked than outward EPC, resulting in a highly non-linear current-voltage relation with Ip decreasing with increasing hyperpolarization. This effect may indicate that DMAE causes a voltage-dependent block of closed acetylcholine-activated ion channels.  相似文献   
6.
Objective Cholesteatoma of the petrous bone extending into the intracranial region is an unusual occurrence. Most cases have been attributed to secondary extension of a primary epidermal blastomatous malformation of the temporal bone into the middle or posterior fossae. Within the past two and a half decades, intracranial extension of acquired aural cholesteatoma has been recognized as a likely alternative to this mechanism. Recent literature has rejoined this observation by considering both primary and secondary cholesteatoma of the petrous bone as a single group, petrosal cholesteatoma. The present study is presented to analyze the clinical presentation, imaging findings, and surgical treatment of six patients with acquired aural cholesteatoma extending into the intracranial region. Findings in this study are compared with the extant literature on congenital and acquired cholesteatoma of the petrous bone. This study proposes that petrosal cholesteatoma is a valid anatomical construct; however, the pathogenesis of petrosal cholesteatoma is still important in understanding the clinical presentation and management of cholesteatoma that extends beyond the usual confines of the middle ear and mastoid. Study Design Retrospective case review conducted at a tertiary referral center. Methods From 1985 to 1999, 477 patients were surgically treated for acquired aural cholesteatoma. Patients with intracranial extension of cholesteatoma were studied. Clinical presentation, imaging studies, operative findings, surgical treatment, and postoperative results were evaluated. Results Six cases in a series of 477 patients with acquired aural cholesteatoma had intracranial extension of disease. In this series, the most frequent pathway for intracranial extension was supralabyrinthine through the supratubal recess into the middle cranial fossa. A less frequent pathway was via the retrofacial air cells into the posterior cranial fossa. Surgical access for removal of intracranial cholesteatoma was accomplished through several approaches including translabyrinthine, transcochlear, retrolabyrinthine, and middle cranial fossa. In two patients who had reoperation for possible residual disease, one was free of residual disease and one was found to have residual cholesteatoma in the region of the horizontal facial nerve. Conclusion Acquired aural cholesteatoma can extend into either the middle or posterior cranial fossae. In this study, cholesteatoma extended into the middle fossa through the supratubal recess along the labyrinthine facial nerve and into or above the internal auditory canal. A less frequent path is through the retrofacial air cells into the posterior fossa. Intracranial acquired cholesteatoma is generally small and presents with complaints related to underlying otitis media rather than the neurological deficits that are often associated with primary petrous bone cholesteatoma. While computed tomography and magnetic resonance imaging are both required to differentiate congenital petrous cholesteatoma from other lesions of the petrous bone, computed tomography of the temporal bone is usually sufficient to diagnosis and define intracranial extension of acquired aural cholesteatoma. These lesions can be completely excised rather than exteriorized.  相似文献   
7.
目的探讨鞍旁硬膜间腔岩尖入路显微手术治疗三叉神经鞘瘤的疗效。方法利用鞍旁硬膜间腔岩尖入路对中颅窝型、中后颅窝哑铃型三叉神经鞘瘤12例进行了显微手术治疗,对术中解剖、手术技巧及疗效进行分析。结果鞍旁硬膜间腔岩尖入路能充分暴露肿瘤,肿瘤全切除9例,次全切除3例;经病理学检查均为神经鞘瘤。术后颅神经功能障碍较术前改善。结论鞍旁硬膜间腔岩尖入路能安全切除肿瘤,提高手术切除率,减少术后并发症。  相似文献   
8.
两种电子根尖定位仪测量准确性的实验研究   总被引:10,自引:4,他引:6  
目的:研究Raypex(5、Root SW两种电子根尖定位仪(electronic apexlocators,EAL)测量准确性。方法:采用琼脂凝胶和单根管离体牙构建EAL体外评价模型,使用两种EAL在同一种电介质中进行根管长度测量,记录测量值(measured length,ML)及测量值和实际值(actual length,AL)之间的差值(IF值)。结果采用Friedman分析。结果:IF值在±0.5mm范围内,Raypex(5为92.5%,Root SW为61.325%;IF值在±1.0mm范围内,Raypex(5为100%,Root SW为87.5%。在本实验中Raypex(5和Root SW测量准确性有显著性差异(P<0.001)。结论:电子根尖定位仪Raypex(5在本实验条件下可以较为准确测量实验牙根管长度。  相似文献   
9.
随着生化节奏的不断加快,各种压力突如其来,失眠成为临床常见疾病。运用针刺、耳穴配合耳尖放血治疗失眠取得良好地疗效。  相似文献   
10.
右心室不同部位起搏的血流动力学比较   总被引:1,自引:0,他引:1  
目的:探讨右室高位室间隔起搏与右室心尖部起搏的血流动力学不同。方法:60例缓慢心律失常患者,具有起搏器植入指征。随机分组,分别行右室高位室间隔起搏(A组)及右室心尖部起搏(B组)治疗。分别于术前、术后行心电图,超声心动图检查。观察QRS波时限,左心室射血分数(LVEF),左室舒张末期内径,每搏量(Sv),E峰值,E/A值,二尖瓣返流量。结果:右室高位室间隔起搏,与右室心尖部起搏比较,QRS波时限增宽程度小,LVEF以及Sv降低程度小。结论:右室高位室间隔起搏比右室心尖部起搏更接近生理性起搏,对血流动力学的不利影响较小,可能是一个更佳的起搏部位。  相似文献   
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