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351.
Wolfram syndrome is a rare neurodegenerative disorder characterized by diabetes insipidus, diabetes mellitus, optic atrophy and deafness (DIDMOAD). A wide spectrum of abnormalities of the central nervous system, urinary tract and endocrine glands is also observed. We report cranial MRI findings in a 32-year-old female patient with Wolfram syndrome. In addition to the classical features, including absence of the normal high signal of the neurohypophysis, atrophy of visual pathways, the brainstem, cerebellum and cerebral cortex, we observed bilateral hyperintensity on proton density- and T2- weighted images related to the optic radiations in the periventricular white matter of the temporal and parieto-occipital lobes, which may reflect gliosis pathologically.  相似文献   
352.
Standard treatment for the majority of malignant brain tumours consists of surgery and radiotherapy. This treatment has late morbidity which is accentuated in the very young child. As part of a strategy to improve quality of life and overall survival of young children with brain tumours, members of the United Kingdom Children's Cancer Study Group (UKCCSG) have piloted an intensive chemotherapy regimen which aims to avoid or delay radiotherapy following surgery. Twenty eight children with a variety of malignant brain tumours have received the regimen, which contains carboplatin, vincristine, cyclophosphamide, methotrexate, and cisplatin. The treatment is toxic, resulting in one death from infection. The bulk of the toxicity was associated with the administration of carboplatin. All but three children eventually required adjuvant radiotherapy and this was given between 1.5 and 27 months from diagnosis (median delay to radiotherapy, 12 months). Using this treatment regimen, overall survival at four years is 35% (confidence intervals 10% to 60%). While there is no evidence from this study that radiotherapy can be abandoned in the management of malignant brain tumours, its introduction may be delayed using suitable chemotherapy, thus allowing time for further CNS development. This treatment strategy has been taken forward as an international clinical trial run through the International Society for Paediatric Oncology, but using a smaller dose of carboplatin to reduce toxicity.  相似文献   
353.
In order to study the influence of sociodemographic factors, postneonatal mortality of all live births surviving the neonatal period registered in the Norwegian Medical Birth Registry in 1978–1982 were examined (n = 209 030). Postneonatal deaths (n = 634) were divided into two categories; deaths due to the sudden infant death syndrom (SIDS) (n = 359) and deaths due to other causes (non-SIDS) (n = 275). SIDS and non-SIDS deaths showed different relationships to sociodemographic factors, and the associations appeared to be different for first-born and later born children. SIDS mortality was highest for first-born offspring when the mother was young (adjusted relative risks (RR) 2.3) and had a low educational level (adjusted RR 4.9). For later-born offspring no association between maternal educational level and SIDS was found, while young maternal age (adjusted RR 4.4) and unmarried status (adjusted RR 2.3) were closely associated with SIDS. In the multivariate model, however, there were no statistically significant associations between non-SIDS and sociodemographic factors for firstborn or later-born children. Thus it appears that the increased postneonatal mortality in lower social groups can be explained by an association with SIDS.  相似文献   
354.
Six preterm infants who developed disproportionate enlargement of the 4th ventricle during the neonatal period, associated with post-haemorrhagic ventricular dilatation (PHVD), before shunt placement are reported. Five of the six preterm infants developed cyanotic spells and/or bradycardias at the time of rapid enlargement of the 4th ventricle, suggestive of raised posterior fossa pressure, which resolved following insertion of and drainage from a subcutaneous reservoir. In one of the three survivors an isolated 4th ventricle was subsequently diagnosed later in infancy, requiring drainage. These data suggest that a combination of an enlarged 4th ventricle on ultrasound and cyanotic spells and/or bradycardias should lead to rapid release of raised pressure in the posterior fossa. Long-term follow-up of these children is necessary, as isolation of the 4th ventricle can subsequently develop. Hydrocephalus, intraventricular haemorrhage, isolated 4th ventricle, preterm infant  相似文献   
355.
Barriers to sustain breastfeeding could be time and place specific. Here, we summarise new and old challenges to breastfeeding during COVID-19 pandemic in Hong Kong, some of which were obtained from qualitative in-depth interviews with health-care professionals. We document how unnecessary massive mother–baby separations in hospitals and doubts in COVID-19 vaccine safety seriously harm breastfeeding. We also discuss how the trends and increase in acceptance of receiving post-natal care from family doctors, online-antenatal class, work-from-home policy and telemedicine implicate new strategies to protect, promote and support breastfeeding during and after the pandemic. The challenges from the COVID-19 pandemic on breastfeeding have revealed new opportunities to support breastfeeding in Hong Kong and similar settings where exclusive breastfeeding for 6 months is still not the norm.  相似文献   
356.
OBJECTIVE: Oral hairy leukoplakia (OHL) is characterised by the presence of a replicative Epstein-Barr virus (EBV) in the superficial layers of the epithelium. There is some doubt, however, whether this reflects activation of a latent infection of the basal epithelial cells. EBV latency is associated with the expression of the viral gene product EBNA-I and the aim of this study was to investigate EBNA-I expression in OHL. METHODS: 22 biopsies of clinically suspicious OHL and three cases of normal mucosa were available as fresh frozen or paraffin embedded material. EBNA-I was detected immunocytochemically using a rat monoclonal antibody (IH4-I) following microwave irradiation. Lytic EBV infection was confirmed by the identification of the BZLF-I protein. RESULTS: 16 of the 22 cases displayed focal replicative EBV meeting the criteria for OHL, and in 13 of these, EBNA-I expression was restricted to the nuclei of epithelial cells in the upper layers of the epithelium. EBNA-I expression was absent from the basal cells in all cases and in the nine BZLF-I negative mucosal biopsies. CONCLUSION: These findings suggest that lytic EBV infection in OHL is not the result of activation of a latent infection of basal cells and suggests a role for EBNA-I, not only in latent EBV infection, but also in virus replication.  相似文献   
357.
358.
Tobacco dependence is a chronic relapsing medical illness. Unfortunately more than 1.1 billion people worldwide smoke tobacco. Tobacco consumption rate is very high in India. Providing three minutes counseling by physicians doubles the cessation rate as compared to no intervention. Nicotine replacement products (gums, transdermal patch, nasal spray, inhaler and lozenge), bupropion and varenicline used with counseling by physicians double the cessation rates at one year. There are drugs like buspirone, naltrexone, mecamylamine and silver acetate; some of which either alone or in combination with any of the above drugs may be routinely used in near future for smoking cessation in at least some specific groups of population. The most difficult problem for patients in smoking cessation is withdrawal symptoms. Counseling with continuous support from physician, family members, friends and overall from the society will help in achieving a higher rate of smoking cessation, with the final aim of making ours a tobacco smoke-free world for future generations.Key Words: Smoking cessation, Nicotine replacement therapy, Bupropion, Varenicline  相似文献   
359.
OBJECTIVE: To study the contralateral ear of patients with chronic otitis media (COM). DESIGN: Transversal. SETTING: Tertiary referral center. PATIENTS: A total of 500 consecutive patients who had been diagnosed as having COM with or without cholesteatoma. INTERVENTIONS: Digital otoendoscopy was performed on both ears. MAIN OUTCOME MEASURE: Pathologic alterations in the contralateral ear. RESULTS: In 75.2% of the patients, the contralateral ear was found to have some structural abnormalities; 60.4% of the patients presented with COM without cholesteatoma, and in this group, 69.9% had an abnormal contralateral ear. In those with cholesteatoma, the contralateral ear was found to be abnormal in 83.3%. The most frequent finding in both groups was retraction of the tympanic membrane. CONCLUSIONS: Patients with COM in 1 ear have a high chance of presenting with some degree of disease in the contralateral side. We believe that our findings suggest that COM should be ideally approached not as a static pathological incident affecting 1 ear but rather as an on-going process that may affect both ears.  相似文献   
360.
背景:不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。设计、时间及地点:调查分析,于1997—01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11418人进行调查统计分析;男3666人,女7752人:年龄20岁~90岁;分别来自北京(2385人)、广州(1178人)、上海(1404人)、南京(2938人)、成都(1425人)、嘉兴(2088人),受试者来源于社区调查、健康体检和健康志愿者。方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11418人L2-L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098g/cm^2和0.027g/cm^2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01g/cm^2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化0.01g/cm^2,则骨质疏松症检出率变化4%(呈负相关)。结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。  相似文献   
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