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151.
The radiation is considered as a double edged sword, as its beneficial and detrimental effects have been demonstrated. The potential benefits are being exploited to its maximum by adopting safe handling of radionuclide stipulated by the regulatory agencies. While the occupational workers are monitored by personnel monitoring devices, for general publics, it is not a regular practice. However, it can be achieved by using biomarkers with a potential for the radiation triage and medical management. An ideal biomarker to adopt in those situations should be rapid, specific, sensitive, reproducible, and able to categorize the nature of exposure and could provide a reliable dose estimation irrespective of the time of the exposures. Since cytogenetic markers shown to have many advantages relatively than other markers, the origins of various chromosomal abnormalities induced by ionizing radiations along with dose-response curves generated in the laboratory are presented. Current status of the gold standard dicentric chromosome assay, micronucleus assay, translocation measurement by fluorescence in-situ hybridization and an emerging protein marker the γ-H2AX assay are discussed with our laboratory data. With the wide choice of methods, an appropriate assay can be employed based on the net.  相似文献   
152.
To standardize femur measurement for the identification of fetuses at risk for Down syndrome, sonographers of varying professional experience and background measured the femurs of 20 Down syndrome fetuses and 709 normal control fetuses. A regression analysis performed to compare biparietal diameter to femur length on the 709 control fetuses yielded the following formula: expected femur length = -9.3105 + 0.9028.biparietal diameter. A ratio of measured-to-expected femur length of 0.91 or lower indicated Down syndrome with a sensitivity of 40%, a specificity of 95%, and a positive predictive value of 3.1%. Eight of the 20 fetuses with Down syndrome (40%) also had a thickened nuchal fold (6 mm or larger). If the nuchal fold findings had been considered with the femur length findings, two more of the fetuses with Down syndrome would have been identified, yielding a sensitivity of 45% and a positive predictive value of 4.3%. Because these measurements were made by eight sonographers rather than a single experienced sonologist, these results could be achieved in most ultrasound laboratories where measurements are done primarily by sonographers.  相似文献   
153.
竹叶椒化学成分的研究   总被引:1,自引:0,他引:1  
自芸香科花椒属植物竹叶椒Zanthoxylum planispinum Sieb. et Zucc根的石油醚提取物中分离得到三种结晶。经物理常数测定,光谱(IR.NMR和MS)及X-射线单晶衍射分析,确定了化合物Ⅲ的绝对构型为(1R,2R,5R,6S)-2-(3′,4′-二甲氧基苯基)-6-(3″,4″-亚甲二氧苯基)双骈四氢呋喃,是一个新化合物,命名为竹叶椒脂素(L-planinin)。化合物Ⅰ为β-香木脂醇(β-amyrin),化合物Ⅱ为L-细辛脂素(L-asarinin),这三种化合物均系首次从本植物中分离得到。  相似文献   
154.
Background The prevalence of hepatitis C (HCV) infection among injection drug users is high and addiction-related care is increasingly being provided by GPs in Ireland. Aims To determine the prevalence and associated factors of HCV infection among injecting drug users attending general practice. Methods The records of 571 patients attending 42 general practices in the Eastern Regional Health Authority (ERHA) area for methadone maintenance treatment were reviewed. Results The HCV status was recorded in 380 cases (67%). Of these, 193 had a test performed by their GP, 74 had been tested by another service and 113 had no evidence of being tested, but HCV status was recorded based on information provided by the patient himself. A total of 276 cases were identified as being HCV positive (prevalence 73%), with no difference in prevalence between the three sources of information (p=0.12). A history of injecting drug use was the major determinant of testing for HCV. Conclusions While a large proportion of drug users attending GPs for methadone maintenance treatment are known to be HCV positive, a considerable number have not been tested. Barriers to testing need to be explored to facilitate comprehensive screening.  相似文献   
155.
以1,4-环己二酮为原料经与哌啶缩合、还原、乙酸汞环合、碱催化分子内缩合等11步反应完成了一叶萩碱的全合成。合成品的熔点及光谱数据与天然一叶萩碱的熔点及光谱数据一致。  相似文献   
156.
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158.
BackgroundThe Oxford–Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) and Public Health England (PHE) are commencing their 54th season of collaboration at a time when SARS-CoV-2 infections are likely to be cocirculating with the usual winter infections.ObjectiveThe aim of this study is to conduct surveillance of influenza and other monitored respiratory conditions and to report on vaccine uptake and effectiveness using nationally representative surveillance data extracted from primary care computerized medical records systems. We also aim to have general practices collect virology and serology specimens and to participate in trials and other interventional research.MethodsThe RCGP RSC network comprises over 1700 general practices in England and Wales. We will extract pseudonymized data twice weekly and are migrating to a system of daily extracts. First, we will collect pseudonymized, routine, coded clinical data for the surveillance of monitored and unexpected conditions; data on vaccine exposure and adverse events of interest; and data on approved research study outcomes. Second, we will provide dashboards to give general practices feedback about levels of care and data quality, as compared to other network practices. We will focus on collecting data on influenza-like illness, upper and lower respiratory tract infections, and suspected COVID-19. Third, approximately 300 practices will participate in the 2020-2021 virology and serology surveillance; this will include responsive surveillance and long-term follow-up of previous SARS-CoV-2 infections. Fourth, member practices will be able to recruit volunteer patients to trials, including early interventions to improve COVID-19 outcomes and point-of-care testing. Lastly, the legal basis for our surveillance with PHE is Regulation 3 of the Health Service (Control of Patient Information) Regulations 2002; other studies require appropriate ethical approval.ResultsThe RCGP RSC network has tripled in size; there were previously 100 virology practices and 500 practices overall in the network and we now have 322 and 1724, respectively. The Oxford–RCGP Clinical Informatics Digital Hub (ORCHID) secure networks enable the daily analysis of the extended network; currently, 1076 practices are uploaded. We are implementing a central swab distribution system for patients self-swabbing at home in addition to in-practice sampling. We have converted all our primary care coding to Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) coding. Throughout spring and summer 2020, the network has continued to collect specimens in preparation for the winter or for any second wave of COVID-19 cases. We have collected 5404 swabs and detected 623 cases of COVID-19 through extended virological sampling, and 19,341 samples have been collected for serology. This shows our preparedness for the winter season.ConclusionsThe COVID-19 pandemic has been associated with a groundswell of general practices joining our network. It has also created a permissive environment in which we have developed the capacity and capability of the national primary care surveillance systems and our unique public health institute, the RCGP and University of Oxford collaboration.  相似文献   
159.
The objective of this study was to investigate the incidence, and the factors influencing the development, of complex regional pain syndrome-I in the upper extremity in hemiplegic patients within the first 28 weeks following a stroke. We followed up 82 stroke patients. All patients were evaluated at weeks 2, 6, 14 and 28 after suffering a stroke. Outcomes were assessed using passive range of motion of shoulder, presence of subluxation, Ashworth score, Motricity index arm score, Brunnstrom stages and depression score. The incidence of complex regional pain syndrome-I was 48.8% in the first 28 weeks. Significant correlation was found between complex regional pain syndrome-I and the presence of subluxation, Ashworth score, Motricity index arm score, Brunnstrom stage and depression score (r=0.259, P=0.019; r=0.271, P=0.014; r=-0.393, P<0.001; r=-0.385, P<0.001; r=0.293, P=0.008, respectively). In this study, there was a relationship between complex regional pain syndrome-I and subluxation, loss of range of motion, spasticity of shoulder muscles and muscle strength. In order to prevent the development of complex regional pain syndrome-I, exercises directed at increasing the range of motion for the glenohumeral joint, strengthening shoulder muscles and reduction of spasticity will establish the integrity of the shoulder joint.  相似文献   
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