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71.
Summary The effect of recurrent periods of ischemia on the myocardium was investigated in 15 open-chest dogs. Ischemia was produced by 3 minutes of proximal occlusion of the left anterior descending coronary artery. Each occlusion was followed by reperfusion of 3 minutes duration. Forty occlusions with a total of 120 minutes of ischemia were performed, and regional function (sonomicrometry) as well as high energy phosphates (needle biopsies) were determined at the end of the 5th, 20th, and 40th period of ischemia and reperfusion. The first periods of ischemia had a cumulative effect both on regional postischemic function (44% and 59% respectively of preischemic control after 20 occlusions) and on the ATP content, but with increasing number of occlusions the additive effects became smaller (ATP reduction/mol/gww/per occlusion). The ATP breakdown per occlusion was diminished with increasing number of periods of ischemia, and no significant adenosine was measured in the ischemic myocardium. Higher than normal postischemic creatine phosphate levels (9.1 mol/g w w at the 40th reperfusion vs. 6.7 mol/gw w control) indicated a functioning oxidative phosphorylation in the presence of an ATP utilization problem at the sarcomere level, because indicators of the cellular energy level (energy charge, free energy change of ATP hydrolysis) quickly normalized during reperfusion. Stunned myocardium is therefore not a problem of energy supply but rather of energy utilization. Reduced ATP utilization and regional dysfunction are the expressions of the same cellular defect which resides either in the ATP-splitting contractile apparatus or in the electromechanical coupling. Contractile dysfunction during reperfusion protects the heart against subsequent periods of ischemia because ATP turnover is reduced.Parts of the results were presented at the 57th Sessions of the American Heart Association, Miami, Florida/U.S.A. 1984 相似文献
72.
Summary This is a review of 1,000 consecutive cases of severe head injury admitted to our Neurosurgical Department between January 1973 and August 1976, before the advent of CT scanning. All patients were comatose following head injury (GCS8) and were treated homogeneously by the same neurosurgical team by a protocol that included immediate resuscitation on arrival, diagnosis of intracranial lesions by angiography, early surgery when needed, mechanical ventilation, steroids, and mannitol. Extracranial lesions, even if preponderant, were treated by various specialists in the Neurosurgical Department, which for all practical purposes operated as an Emergency Department. Admission criteria were very broad with no preadmission selection. The overall mortality for this series was 45%. A little less than half the patients made good recoveries or remained moderately disabled (47%); 6% were severely disabled, and 2% survived in a persistent vegetative state. More than two-thirds of the patients were brought to our Neurosurgical Department after a short stay at a general hospital; 72% were admitted within 6 hours of injury; 71% were traffic accident victims; and 34% had significant associated extracranial injuries. Carotid angiography was performed in 78% of the patients and indicated the presence of an intracranial haematoma requiring surgery in 36% of the whole series. Mortality was significantly higher in operated than in unoperated patients (56% versus 39%); those treated surgically, however, were older, in worse clinical condition, and showed a higher incidence of acute subdural haematomas associated with brain contusion. Carotid angiography proved very effective in revealing the presence of an expansive lesion but failed to reflect the severity of brain damage, since the group with negative angiograms showed a high mortality (52%). Patients with a lucid interval had a higher percentage of surgical lesions than those with immediate coma (58% versus 26%); but fully 42% of them did not require surgery, and 25% had negative angiograms. From the prognostic point of view the clinical data elicited after initial resuscitation were highly predictive of the outcome: some individual neurological signs, such as mydriasis, posturing and eye movements, were not inferior to the GCS score in that respect. Age also proved a strong predictor, since elderly patients are more likely to have severe subdural and parenchymal lesions and their clinical severity is accordingly greater.Our series amounts to a data bank of cases both contemporary to and in good agreement with that collected by Jennett and his associates in their 1977 multinational study; and it affords a useful reference in the assessment of epidemiological variations and alternative management in relation to outcome. 相似文献
73.
《Value in health》2022,25(5):677-684
ObjectivesHealthcare policy makers should ensure optimal patient access to medical nutrition (MN) as part of the management of nutrition-related disorders and conditions. Questions remain whether current healthcare policies reflect the clinical and economic benefits of MN. The objective of this article is to characterize coverage and reimbursement of MN, defined as food for special medical purposes/medical food for a diverse set of countries, including Australia, Belgium, Brazil, Canada, China, France, Germany, Hong Kong, Italy, Japan, The Netherlands, Singapore, Spain, United Kingdom, and United States.MethodsData sources included published literature and online sources. ISPOR’s Nutrition Economics Special Interest Group developed a data collection form to guide data extraction that included reimbursement coverage, years that reimbursement policies were established, and presence of a formal health technology assessment (HTA) for MN technologies.ResultsReimbursement coverage of MN technologies varied across the countries that were reviewed. All but 3 countries limited coverage to specific formulations of products, regardless of demonstrated clinical benefit. The year that reimbursement policies were established varied across countries (ranging from 1984 to 2017), and only 4 countries regularly update policies. France and Brazil are the only countries with a formal HTA process for MN technologies.ConclusionsMost countries have limited MN reimbursement, have not updated reimbursement policies, and lack HTA for MN technologies. These limitations may lead to suboptimal access to MN technologies where they are indicated to manage nutrition-related disorders and conditions, with the potential of negatively affecting patient and healthcare system outcomes. 相似文献
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75.
Shujuan Li Yacong Bo Hongyan Ren Chen Zhou Xiangqian Lao Liyun Zhao Dongmei Yu 《Nutrients》2021,13(4)
Infantile anaemia has been a severe public health problem in China for decades. However, it is unclear whether there are regional differences in the prevalence of anaemia. In this study, we used data from the China Nutrition and Health Surveillance (CNHS) to assess the prevalence of anaemia and the risk factors associated with its prevalence in different regions. We included 9596 infants aged 0–23 months from the CNHS 2013 database. An infant was diagnosed with anaemia if he/she had a haemoglobin concentration of <110 g/L. We used multivariate logistic regression to investigate the potential risk factors associated with the development of anaemia. We found that anaemia was present in 2126 (22.15%) of the infants assessed. Approximately 95% of these cases were classified as mild anaemia. Based on the guidelines laid out by the World Health Organization, 5.5% and 43.6% of the surveillance sites were categorized as having severe and moderate epidemic levels of anaemia, respectively. The prevalence of infantile anaemia in Eastern, Central and Western China was 16.67%, 22.25% and 27.44%, respectively. Premature birth, low birth weight, breastfeeding and residence in Western China were significantly associated with higher odds of developing anaemia. Female sex and having mothers with high levels of education and maternal birth age >25 years were associated with lower odds of developing anaemia. In conclusion, we observed significant regional disparities in the prevalence of infantile anaemia in China. Western China had the highest prevalence of infantile anaemia, and rural regions showed a higher prevalence of anaemia than urban regions. 相似文献
76.
77.
78.
目的:探讨内皮素(ET)-1和一氧化氮(NO)在蛛网膜下腔出血(SAH)后脑血管痉挛(CVS)及脑缺血性损害中的作用。方法:采用非开颅法大鼠SAH模型,检测24h内血及脑组织中NO和ET-1含量,并测定脑微区血流(rCBF)和基底动脉管径。结果:大鼠SAH后30min基底动脉管径缩小,rCBF持续下降;血NO减少,ET-1增多;脑组织NO和ET-1均增加。结论:血NO减少,ET增多系SAH后CVS发生的原因之一;脑组织NO和ET增多则加重脑损伤。 相似文献
79.
Velocity data from tissue Doppler imaging (TDI)can provide valuable information on regional leftventricular wallmotion. Validation of TDImyocardialvelocity measurements has been carried out indirectlyfrom gray- scale M- mode images,and discrepancieshave been reported.Mc Dicken[1] and Miyatake etal[2 ]have reported the accuracy and validity of the TDIsystem using a rotating sponge model.However theoverall motion of the heart should be considered.Inthe present study,we described a new TDI… 相似文献
80.
与鼻内镜手术相关的鼻泪管解剖测量 总被引:2,自引:0,他引:2
刘玉欣 《青岛大学医学院学报》2001,37(3):217-218
①目的 熟悉鼻泪管的局部解剖关系 ,为鼻内镜下鼻泪管的手术提供依据。②方法 对 5 6侧正中矢状位切开尸头的鼻泪管进行解剖学测量。③结果 鼻泪管开口位于下鼻道前 1/ 3段顶或侧壁 (30侧 ,2 6侧 )。鼻泪管长度为 (15 .99± 2 .5 2 )mm ,鼻泪管上口径平均 2 .97mm ,鼻泪管中段管径 4.2 0mm ,鼻泪管上口内侧壁厚平均 0 .73mm ,中段内侧壁厚平均 0 .5 5mm ,鼻泪管下口前缘至前鼻棘距离平均 2 1.97mm ,下口前缘至下鼻甲前缘附着处的距离平均为 10 .5 4mm ,上颌窦开口前缘到鼻泪管后壁的距离平均 3.82mm ,鼻泪管长轴与眉间至前鼻棘连线的夹角为 8.74°± 1.39° ,以上各指标左右侧比较差异无显著性 (t =- 0 .983~ 1.481,P >0 .0 5 )。④结论 鼻泪管上口位于鼻丘隆突下缘 ,下口位于下鼻道前端顶或侧壁 ,是鼻内镜鼻腔泪囊造口术的重要标志。 相似文献