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121.
黄花远志根化学成分的分离和结构鉴定   总被引:16,自引:0,他引:16  
从黄花远志(Polygala arilata Buch-Ham.)根中分离得到7个化合物,根据光谱(UV,IR,MS,1HNMR,DIFNOE和13CNMR)解析和理化性质,分别鉴定为1-甲氧基-2,3-亚甲二氧基口山酮(I)、1,7-二羟基-2,3-亚甲二氧基口山酮(II)、1,6,7-三羟基-2,3-二甲氧基口山酮(II)、对羟基苯甲酸(IV)、远志醇(V)、豆甾醇(VI)、豆甾醇β-D-吡喃葡萄糖甙(VII)。其中,I和II为新化合物,VI和VI为首次从该植物中分得。化合物I~II有抑制醛糖酶的作用。  相似文献   
122.
犬冠状动脉定量狭窄造成急性心肌缺血,观察巴曲酶(batroxobin)对冠脉循环及血流动力学的影响。结果显示,batroxobin可剂量依赖性地增加缺血心脏冠脉血流量,2BU·kg-1(0.1BU·kg-1·min-1)iv后40min,缺血犬冠脉流量比盐水对照组增加12%,此时小冠脉阻力由4.1±0.5降至3.2±0.5mmHg·min·ml-1,而大冠脉阻力无明显变化;给药后120min,上述作用仍然持续,且冠脉总阻力降低13%,左室压上升及下降最大速率与盐水对照组相比分别增大14%和16%。结果表明,batroXobin在冠脉低灌流状态下仍可降低小冠脉阻力,增加冠脉流量,这可能是其改善缺血犬冠状循环及心脏功能的机理之一。  相似文献   
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The authors prospectively evaluated 82 neonates, ranging in gestational age from 29 to 44 weeks postconception, with magnetic resonance (MR) imaging at 0.6 T. Twenty-two cases of hemorrhage in 15 infants were identified. Ultrasound (US) and computed tomography (CT) were superior to MR in the first few days after parenchymal hemorrhage, since at this time lesions were apparent on only T2-weighted images. After the first 3 days, MR was the single best modality because (a) hemorrhage on CT became imperceptible in the 2d week, whereas the high signal of hemorrhage on MR persisted for 2-11 weeks; (b) MR permitted rough dating of hemorrhage according to changes in signal intensity; and (c) MR was superior in identifying subdural or epidural hemorrhage. Because of the nonspecificity and restricted field of view of US and the inability of CT to depict hemorrhage after 7-10 days, the authors conclude that MR significantly improves the detection of intracranial hemorrhage in neonates.  相似文献   
125.
Uteroglobin基因G38A多态性与IgA肾病相关关系   总被引:2,自引:0,他引:2  
[目的]研究Uteroglobin基因G38A多态性与我国IgA肾病的相关关系.[方法]用PCR-RFLP法和PCR产物直接测序法鉴定基因型,采用以家庭为基础的传递不平衡检验(transmission disequilibrium test,TDT)、单倍体相对风险(haplotype-based haplotype relative risk,HRR)分析,以及病例-对照研究分析Uteroglobin基因G38A多态性与我国IgA肾病的相关关系.[结果]①GG基因型在IgA肾病伴高血压组与肾功能进展组中的分布频率显著高于AA GA(P=0.042,x2=4.117;P=0.039,x2=4.240)(病例组362例、正常对照组201例);②135个满足TDT分析的核心家庭中,杂合子父母传递给患病子代的等位基因频率不比预期值高(x2=0.457,P=0.499);③HRR分析显示此多态性不使患者具有更高的发病风险(x2=0.520,P=0.471,HRR=0.878).[结论]Uteroglobin GG基因型可能和IgA肾病的进展及高血压相关,但和IgA肾病的易感性不相关.  相似文献   
126.
Eighty-five infants, 82 of whom were 29-44 weeks postconceptional age, were imaged with a 0.6-T magnet. Eight infants had cerebral infarction. In premature neonates with very water, low-intensity white matter on T1-weighted images, ultrasound was better than both computed tomography and magnetic resonance (MR) imaging in depicting parenchymal changes of infarction or edema. However, after 37 weeks gestation, MR imaging was superior. Cerebral atrophy, present in seven infants, was consistent with subarachnoid space widths of 7 mm or more, or subarachnoid space widths of 5-6 mm with ventricular/brain ratios of 0.36 or greater. Delayed myelination was seen in a total of 18 infants with histories of hypoxic-ischemic insult. MR imaging shows promise in the neonatal period. It facilitates recognition of infarcts in full-term infants and may be used to predict abnormal neurologic outcome in infants who have initial delayed myelination.  相似文献   
127.
目的:探讨退化性脊椎病变前方入路手术的适应证,方法:回顾性分析142例接受过前方手术的病例,根据不同病情,划分出不同组别,。分别讨论其预后,结果:总体疗效评价优等者占82%,一般者占15%,不好者占3%,结论:总结出4项适应证;(1)椎间盘突出症,尤其是中央型突出者以及椎间盘伴有过渡型腰骶变形者。(2)脊椎骨关节病变为主的病灶。(3)I度脊前倾滑脱症者,或其合并有椎间盘病变者。(4)曾接受椎间盘手术,因残余的软骨压迫导致严重的临床症状者。  相似文献   
128.
CK King  R Glass  JS Bresee  C Duggan   《MMWR Recomm Rep》2003,52(RR-16):1-16
Acute gastroenteritis remains a common illness among infants and children throughout the world. Among children in the United States, acute diarrhea accounts for >1.5 million outpatient visits, 200,000 hospitalizations, and approximately 300 deaths/year. In developing countries, diarrhea is a common cause of mortality among children aged <5 years, with an estimated 2 million deaths annually. Oral rehydration therapy (ORT) includes rehydration and maintenance fluids with oral rehydration solutions (ORS), combined with continued age-appropriate nutrition. Although ORT has been instrumental in improving health outcomes among children in developing countries, its use has lagged behind in the United States. This report provides a review of the historical background and physiologic basis for using ORT and provides recommendations for assessing and managing children with acute diarrhea, including those who have become dehydrated. Recent developments in the science of gastroenteritis management have substantially altered case management. Physicians now recognize that zinc supplementation can reduce the incidence and severity of diarrheal disease, and an ORS of reduced osmolarity (i.e., proportionally reduced concentrations of sodium and glucose) has been developed for global use. The combination of oral rehydration and early nutritional support has proven effective throughout the world in treating acute diarrhea. In 1992, CDC prepared the first national guidelines for managing childhood diarrhea (CDC. The management of acute diarrhea in children: oral rehydration, maintenance, and nutritional therapy. MMWR 1992;41[No. RR-16]), and this report updates those recommendations. This report reviews the historical background and scientific basis of ORT and provides a framework for assessing and treating infants and children who have acute diarrhea. The discussion focuses on common clinical scenarios and traditional practices, especially regarding continued feeding. Limitations of ORT, ongoing research in the areas of micronutrient supplements, and functional foods are reviewed as well. These updated recommendations were developed by specialists in managing gastroenteritis, in consultation with CDC and external consultants. Relevant literature was identified through an extensive MEDLINE search by using related terms. Articles were then reviewed for their relevance to pediatric practice, with emphasis on U.S. populations. Unpublished references were sought from the external consultants and other researchers. In the United States, adoption of these updated recommendations could substantially reduce medical costs and childhood hospitalizations and deaths caused by diarrhea.  相似文献   
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Radiographic skeletal examinations were performed in eight adult patients who had received the aromatic retinoid etretinate for various disorders of keratinization over periods ranging from 1 to 7 years. Age- and sex-matched controls were also examined. In all patients, alterations of ossification were found to a varying degree, including calcification of the anterior spinal ligament, vertebral hyperostoses at the anterosuperior and anteroinferior margins of the vertebral bodies, unilateral bridging of vertebral bodies, hyperostoses of the calcanei at the insertion of the plantar ligament and bone accretion at the anterolateral lips of the acetabula. All the bone changes were asymptomatic. Serum calcium, inorganic phosphate, alkaline phosphatase, calcitonin and parathormone were within normal physiological ranges. In general, the bone changes observed after long-term etretinate treatment closely resembled the effects of isotretinoin on the skeleton.  相似文献   
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