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脊柱裂动物模型制作与胚胎发生机制探讨   总被引:6,自引:4,他引:2  
目的 建立大鼠隐性脊柱裂和显性脊柱裂畸形动物模型,观察丙戊酸钠和维甲酸诱导大鼠脊柱裂畸形的特点,初步探讨脊柱裂畸形的发生机制。方法 雌性Wistar孕鼠随机分成组:对照组,实验组分成丙戊酸钠三个不同剂量组和维甲酸组。对照组孕鼠不予任何处置,20d胎鼠脊柱染色标本采集图像经计算机软件显微图像分析,测量出每个椎体椎弓两个软骨端距离,目的确定软骨端距离参考值。雌性Wistar大鼠,在确定怀孕的第9d9:00、16:00,按体重计算剂量后于后肢皮下注射20%丙戊酸钠溶液。妊娠第20d剖宫,检查胚胎外观,判定是否有外观可见畸形,然后取脊柱进行骨和软骨双重染色,染色后标本采集图像测量出每个椎体椎弓两个软骨端距离。参照正常胎鼠确定的参考值判定隐性脊柱裂。Wistar大鼠确定怀孕的第10d9:00,胃管灌入维甲酸矿物油混悬液135mg/kg(40mg/m1),妊娠第20d剖宫,检查胚胎外观判定显性脊柱裂畸形发生情况并记录。结果 丙戊酸钠诱导隐性脊柱裂畸形随药物剂量加大,畸形发生率升高,丙戊酸钠剂量400mg/kg、450mg/kg、500rng/kg~导畸形发生率分别是80%、93%、100%,腰椎对丙戊酸钠的致畸作用最敏感;丙戊酸钠还可以导致头端神经管畸形,未观察到显性脊柱裂的发生。维甲酸135rng/kg诱导胎鼠显性脊柱裂的发生率52.3%,畸形都发生在腰骶段,其他畸形的总发生率高达90.7%。结论 丙戊酸钠抑制软骨细胞增生,影响椎体的软骨发生使椎弓不能闭合导致胎鼠隐性脊柱裂的发生。腰椎对丙戊酸钠的致畸作用最敏感,隐性脊柱裂多发生在腰骶段。过量的维甲酸直接影响神经上皮细胞、神经嵴细胞、原基器官间质细胞的生化过程和尾端未分阶段的中胚层,导致胚胎尾端发育不良综合症复杂畸形出现。丙戊酸钠和维甲酸通过不同机制导致畸形的发生。  相似文献   
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隐性脊柱裂排尿功能异常的临床特征   总被引:5,自引:0,他引:5  
目的:研究伴有排尿功能障碍的隐性脊柱裂患者临床特征。方法:总结41例有明显排尿功能障碍的隐性脊柱裂患者临床资料。以18岁为界,将患者分为儿童组和成人组,所有患者均接受X线检查,除4例儿童外,均接受普通尿流动力学检查。结果:儿童组发病高峰年龄在1~2岁,主要临床表现为持续性原发性遗尿,部分伴有尿频、尿急及轻度急迫性尿失禁现象;成人组发病高峰年龄在18~26岁,主要临床表现为尿频、尿急、排尿前踌躇、排尿困难、遗尿等。结论:隐性脊柱裂患者常有排尿功能异常表现,出现症状的高峰时间为出生后及青春发育期后。X线、CT、MRI和尿流动力学等检查在隐性脊柱裂排尿功能障碍的诊断和治疗方案制定中有重要地位。  相似文献   
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Background Cystic dysraphic lesions of the cervical and upper thoracic region are rare and only a few series have been published about the topic. These malformations can be divided into categories that include both myelocystoceles and the so-called cervical meningoceles or myelomeningoceles.Methods A retrospective study of 18 patients was conducted.Results In 17 patients a squamous or a cicatricial epithelium of variable thickness covered the dome of the lesions, while the base was covered with full-thickness skin. In one case the skin was entirely normal. Four patients displayed associated CNS malformations and three more had systemic congenital anomalies. All patients underwent surgical exploration and the length of time between birth and surgery ranged from 6 h to 9 months. The most frequent surgical finding, seen in 14 patients, was a stalk connecting the dorsal surface of the spinal cord to the cyst. In three patients the findings were consistent with myelocystocele. Only in one case was a true meningocele found. Hydrocephalus and Chiari II malformation were not as consistently associated as in myelomeningoceles. Neurological signs and symptoms were not so marked as in myelomeningoceles and were found in the follow-up of four patients. In two of them there was a non-progressive deficit, probably expressing an imperceptible involvement of the nervous system in the first year of life. The histopathological findings were of three types: neuroglial stalks, fibrovascular stalks and myelocystoceles.Conclusions Cystic dysraphisms of the cervical and upper thoracic region differ clinically and structurally from meningomyelocele and have a more favorable outcome. We believe that these malformations have not been properly labeled and propose a classification based on the structures found inside the cyst.  相似文献   
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Summary The primary tethered cord syndrome has been documented mainly in children and adolescents but also in adults, and patients may present with backache, neuromuscular skeletal changes such as club-foot, scoliosis, muscular atrophy, disturbances of gait, or dysfunction of bladder and rectum, or a combination of these conditions. The cadaveric case presented describes plain film radiographic and anatomical findings of spina bifida occulta at the first and second sacral levels, and an enlarged spinous process of the fifth lumbar vertebra, in a 78 year old male cadaver with a tethered spinal cord terminating at the first sacral level. During life, this man had not undergone surgery for tethered spinal cord.
Revue du syndrome de moelle attachée: étude radiologique et anatomique à propos d'un cas
Résumé Le syndrome de moelle attachée primaire a souvent été décrit chez l'enfant et l'adolescent mais aussi chez l'adulte, les patients pouvant se présenter avec des douleurs du dos, des modifications neuro-musculaires et squelettiques comme un pied bot, une scoliose, une atrophie musculaire, des anomalies de la marche, des dysfonctionnements de la vessie et/ou du rectum, ou une combinaison de ces différents symptômes. L'observation rapportée ici est l'étude anatomique et radiologique d'un spina bifida oculta des première et deuxième vertèbres sacrées associé à l'élargissement du processus épineux de la cinquième vertèbre lombaire chez un cadavre mâle de 78 ans ayant une moelle épinière attachée au niveau de la première vertèbre sacrée. Durant sa vie ce patient n'avait pas subi de chirurgie pour cette moelle attachée.
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Congenital intraspinal lipomas are frequently responsible for progressive neurological deficits caused by distortion or compression of the nervous system. Since fat metabolism in these lesions has not been previously studied, the aim of this study was to determine whether intraspinal lipoma cells behave like lipomas or like normal adipocytes. In 11 patients, intraspinal lipoma cells were compared with normal adipocytes isolated from adjacent subcutaneous adipose tissue for the following parameters: lipoprotein lipase (LPL), lipogenesis from U14C glucose, ß-receptor number, adenylate cyclase activity, cyclic AMP production, and lipolysis in response to ß- and 2-adrenergic agonists. No significant difference between these two cell populations was found, suggesting that intraspinal lipomas are not lipomatous tumors, but hamartomatous lesions capable of growth and regression along with the changes in the rest of the fatty pool. This emphasizes the danger of an abnormal weight gain, as well as the possible usefulness of an hypocaloric diet in patients who worsen in spite of previous surgery.Research supported by INSERM (CRL 824005 and CRE 854010) and the D.G.R.  相似文献   
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BackgroundSelf-management is critical to optimizing the health of individuals with a chronic condition or disability and is, therefore, a central concept in individual and family-centered healthcare delivery. The purpose of this review is to report the state of the science of self-management for individuals with spina bifida (SB) from a lifespan perspective.ObjectiveThis review will summarize the (a) development and use of self-management skills and behaviors across the life span, (b) factors related to self-management behaviors, (c) development of generic or condition-specific measures of self-management used with a spina bifida population, and (d) development and/or outcomes of interventions to improve self-management in SB.MethodsThe search strategy was limited to primary research articles published between 2003 and 2019 and followed PRISMA guidelines. The databases searched included: PubMed, CINAHL, PsycINFO, Web of Science, Cochrane, and Google Scholar. Studies that addressed self-management concepts in individuals throughout the life span and published in English were included.ResultsThe search yielded 108 citations and 56 articles met inclusion/exclusion criteria. A systematic narrative synthesis was reported. The level of evidence identified was primarily Level III articles of good quality. Multiple demographic, environmental, condition and process factors were related to self-management behaviors. SB self-management instruments and intervention development and testing studies were identified.ConclusionsThis review provides a synthesis of the state of the science of self-management including factors related to self-management behaviors, preliminary evidence of instruments for use in SB, factors important to consider in the development and testing of future interventions, and gaps in the literature.  相似文献   
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