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1.
Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students. 相似文献
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Murtaugh LC Stanger BZ Kwan KM Melton DA 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(25):14920-14925
Multiple cell types of the pancreas appear asynchronously during embryogenesis, which requires that pancreatic progenitor cell potential changes over time. Loss-of-function studies have shown that Notch signaling modulates the differentiation of these progenitors, but it remains unclear how and when the Notch pathway acts. We established a modular transgenic system to heritably activate mouse Notch1 in multiple types of progenitors and differentiated cells. We find that misexpression of activated Notch in Pdx1-expressing progenitor cells prevents differentiation of both exocrine and endocrine lineages. Progenitors remain trapped in an undifferentiated state even if Notch activation occurs long after the pancreas has been specified. Furthermore, endocrine differentiation is associated with escape from this activity, because Ngn3-expressing endocrine precursors are susceptible to Notch inhibition, whereas fully differentiated endocrine cells are resistant. 相似文献
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Lactitol and lactulose for the treatment of subclinical hepatic encephalopathy in cirrhotic patients. A randomised, cross-over study 总被引:2,自引:0,他引:2
Fourteen patients with cirrhosis and subclinical hepatic encephalopathy were randomised to treatment with lactitol or lactulose for a 2-month period during which they were monitored clinically, by electroencephalography and by manually administered and computer-based psychometric testing. Following a washout period of 4-6 weeks patients were crossed-over to treatment with the alternative sugar for a similar period of monitoring. None of the patients showed evidence of overt hepatic encephalopathy and only one showed slowing of the electroencephalogram mean cycle frequency at the onset of the trial. However, significant impairment was observed in the group as a whole in the performance of all three manually administered psychometric tests and in four of the ten computer-based test variables. No changes were observed in clinical status or in electroencephalogram mean cycle frequency during treatment with either lactitol or lactulose. However, psychometric performance improved consistently, and to the same degree, during treatment with both sugars. Patients required a mean of 26 g (range 8-36) of lactitol and 25 ml (10-60) of lactulose to achieve two semi-soft stools per day. The majority of patients complained of flatulence during treatment with both sugars but this tended to resolve with continued treatment. Diarrhoea developed in a small number of patients during both treatment periods but this was invariably dose-related. Patients were equally divided in their preference for the two sugars. Patients with subclinical hepatic encephalopathy benefit from treatment with lactitol and lactulose in terms of their psychometric performance. The feasibility and benefits of long-term treatment for this condition need to be elucidated. 相似文献
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Jennifer Stanger Kelley Zwicker Susan Albersheim James J. Murphy III 《Journal of pediatric surgery》2014
Background
Human milk fortifier (HMF) is used in neonatal units throughout North America to facilitate growth of preterm infants. Little data is available on the gastrointestinal side effects and potential adverse events. The purpose of this paper was to present a series of infants presenting with bowel obstruction associated with HMF.Methods
Cases of HMF obstruction were collected between January 2010 and December 2012. Charts were reviewed and relevant data was collected.Results
During the study period, 7 premature infants presented with bowel obstruction secondary to intestinal concretions of HMF. All babies were premature with gestational ages from 25 to 27 weeks. Birth weight was less than 1000 grams in all patients. Patients presented with feeding intolerance, bilious aspirates, abdominal distension, and obstipation. Four of the patients presented with acute deterioration and required urgent surgical intervention.Conclusions
HMF is an important source of nutritional support in infants, which is felt to be safe. We present a series of infants where its use has resulted in significant complications. HMF should be used with caution in infants, especially those with a history of necrotizing enterocolitis. Further research should examine the calcium, protein, and fatty acid concentration tolerable in the gastrointestinal tract of infants. 相似文献9.
Nicholas Stanger Lisa Whitaker Susan H. Backhouse 《Scandinavian journal of medicine & science in sports》2020,30(8):1529-1543
Although research investigating doping in sport is burgeoning, there is still a lack of proxy measures of doping behavior that have undergone extensive psychometric testing. To address this issue, we modified a previously used measure of doping willingness in sport and tested aspects of validity and reliability across four studies. In Study 1, we provided support for the face and content validity of the items, and then found support for the factor structure of the scale in a sample of athletes (N = 205) using confirmatory factor analysis. In Study 2, we collected data from an independent sample of athletes (N = 236) to provide further evidence for the factor structure of the scale using confirmatory factor analysis as well as provided evidence for concurrent and discriminant validity. In Study 3, a further independent sample of athletes (N = 144) completed the scale and provided support for discriminant and predictive validity of the scale. In Study 4, we collected data from a further independent sample (N = 74) to provide support for the test-retest reliability, and stability of items. Lastly, a confirmatory factor analysis was conducted on the samples across Studies 3 and 4, and the composite sample across all four studies which provided further support for the factor structure of the final 8-item scale. Taken together, these findings provide psychometric support for the scale to be used to measure the willingness of athletes to use banned substances to help facilitate future research investigating doping in sport. 相似文献
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目的:在成功分离人皮肤角质形成细胞的基础上,观察表皮生长因子受体在人皮肤角质形成细胞中的表达情况。方法:实验于2006-3/10在北京大学深圳医院中心实验室进行。采用dispase Ⅱ-trypsin两步消化法获取表皮基底层细胞,用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液进行培养。小鼠皮肤成纤维母细胞的预处理:向对数生长期的小鼠皮肤成纤维母细胞培养液中加入丝裂霉素C至终浓度为4mg/L,37℃下培养4h,弃去培养液,用D-Hank’s液洗3次,加入浓度为0.25g/L的胰蛋白酶消化,分离出细胞,离心(200g,5min),用黄素腺嘌呤二核苷酸培养液悬浮细胞,计数,以5.0×104/cm2的密度种于培养皿内,37℃、体积分数0.05的CO2培养箱下培养。角质形成细胞的培养:将分离的角质形成细胞悬浮在黄素腺嘌呤二核苷酸培养液中,以2.0×104/cm2的密度接种在前1天经丝裂霉素C处理的小鼠皮肤成纤维母细胞滋养层上,37℃、体积分数0.05的CO2培养箱下培养。24h换液,以后每3d换1次液。采用免疫细胞化学的方法检测表皮生长因子受体的表达,采用复合逆转录聚合酶链反应检测角质形成细胞中表皮生长因子受体mRNA的表达。结果:采用dispaseⅡ消化法分离了真皮和表皮,获得较多的角质形成细胞,可以避免真皮成纤维细胞的污染。人皮肤角质形成细胞在黄素腺嘌呤二核苷酸培养液中培养5d可见明显的集落,约10d可长满单层。免疫细胞化学显示表皮生长因子受体在细胞表面有明显的表达,复合逆转录聚合酶链反应显示表皮生长因子受体mRNA有明显的表达。结论:用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液可以较好地培养原代人皮肤角质形成细胞,表皮生长因子受体在细胞表面有明显的表达,这些结果为与表皮生长因子受体相关的皮肤病(如银屑病)的研究奠定了基础。 相似文献