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排序方式: 共有980条查询结果,搜索用时 0 毫秒
1.
Michael C. Cheung Eduardo A. Perez Manuel A. Molina Xiaoling Jin Juan C. Gutierrez Dido Franceschi Alan S. Livingstone Leonidas G. Koniaris 《Journal of gastrointestinal surgery》2008,12(4):731-738
Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM).
Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried.
Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000.
Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum
(22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis
demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival.
MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest
median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence
of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced
tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors
of poorer outcome.
Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality
that significantly improves survival. 相似文献
2.
3.
Buckner C Gines LG Saunders CJ Vojtech L Srivastava I Gettie A Bohm R Blanchard J Barnett SW Safrit JT Stamatatos L 《Virology》2004,320(1):167-180
The potential of vaccine-elicited anti-HIV envelope antibodies to control HIV-infection was evaluated by immunizing macaques with the HIV envelope protein and transiently depleting them of their CD8+ cells before intravenous challenge with the pathogenic CCR5-tropic SIV/HIV chimeric virus, SHIV(SF162P4). Although sterilizing immunity was not achieved, all vaccinated animals effectively controlled infection and remained free of disease for the duration of observation (over 3 years). In contrast, during the same period, the control animals progressed to disease. Both the vaccinees and the controls developed robust cell-mediated antiviral and neutralizing antibody responses following infection. A comparative analysis of these responses suggests that the more effective long-term control of infection by the vaccinated animals is due to the more rapid development of anti-HIV envelope antibodies. These studies suggest that priming by vaccination of B cell anti-HIV envelope responses maybe crucial for the long-term control of HIV infection. 相似文献
4.
The currently accepted premise that the diagnosis of hypertrophic pyloric stenosis (HPS) should be made on clinical grounds, with ultrasound (US) and upper gastrointestinal series (UGIS) reserved for those with a negative clinical examination, was tested. Variable clinical skills of initial examiners, including pediatric surgeons, made abdominal palpation no more sensitive or specific than US or UGIS. For those with a negative clinical examination, proceeding directly to a UGIS will result in monetary savings, especially if good clinical performance decreases the probability of HPS among those without palpable pyloric "tumors." The benefits of a "US first" approach (no radiation, better patient and parent acceptance, no contrast medium) are less apparent but no less important and increase as clinical experience declines and performance of US improves. Criteria for the clinical or sonographic diagnosis of HPS should be kept strict to avoid false-positive results; false-negatives and other causes of vomiting should be identified by UGIS. 相似文献
5.
Robert R. Ozsvath Mehdi Poustchi-Amin John C. Leonidas Sheryl S. Elkowitz 《Pediatric radiology》1997,27(2):175-177
Objective. The objective of this study was to determine whether the size of the pyloric mass is one of the factors in the surgeon's
ability to palpate the pyloric “olive”. Materials and methods. The ultrasonographic images and medical records of 60 infants with surgically confirmed hypertrophic pyloric stenosis (HPS)
were reviewed. The pyloric diameter (PD) and pyloric length (PL) were measured and the pyloric volume (PV) was calculated
using the equation PV = 1/4π× (PD)2× PL. Based on the pediatric surgeon's physical examination the infants were divided into two groups: those with and those
without palpable pyloric masses. Results. Infants with a palpable pyloric mass had an average pyloric volume of 3.33 ± 1.76 mm3, which was statistically larger than those whose hypertrophied pylorus could not be palpated (average volume 2.59 ± 2.07
mm3, P < 0.01). There was no statistically significant age difference between the two groups. Conclusion. Clinical skill of the examiner and other clinical aspects (patient cooperation, etc.) determine palpability of the pylorus
in HPS. The size of the hypertrophied pylorus is also an important factor affecting the clinican's ability to palpate the
pyloric mass.
Received: 29 December 1995 Accepted: 7 June 1996 相似文献
6.
Objective. To assess the value of head ultrasound (HUS) in neurologically normal infants with macrocephaly and to develop a rational
approach to radiological investigation of macrocephalic infants. Materials and methods. A retrospective analysis of infants with macrocephaly (seen by one pediatric neurologist at this institution) was conducted.
Infants with normal neurological examinations, no evidence of raised intracranial pressure and who had undergone a HUS were
included. Results. Twenty-seven infants were included in the analysis. Mean age at first assessment was 4.8 months. In 12 of 27 (44 %), HUS
was reported as normal. The remaining 15 had clinically insignificant abnormalities on HUS; 7 had prominent ventricles and
7 had increased subarachnoid fluid, with 1 infant having both. Seven infants had CT or MRI in addition to HUS. No clinically
significant abnormalities were seen on CT or MRI scans that were not evident on HUS. Four infants had mild developmental abnormalities
on initial evaluation. Mean duration of follow-up was 13.1 months. No infant developed neurological abnormalities during the
follow-up period. Conclusion. In infants with macrocephaly with a normal neurological examination and no signs of raised intracranial pressure, HUS in
conjunction with close neurological follow-up is reliable for the detection or exclusion of relevant intracranial pathology.
Received: 22 May 1997 Accepted: 24 October 1997 相似文献
7.
Maxwel Mono Tobias Wretborn Ulrika Rova Leonidas Matsakas Paul Christakopoulos 《RSC advances》2022,12(44):28599
Halophytes are a potential source of lignocellulosic material for biorefinery, as they can be grown in areas unsuitable for the cultivation of crops aimed at food production. To enable the viable use of halophytes in biorefineries, the present study investigated how different organosolv process parameters affected the fractionation of green pressed fibers of Salicornia dolichostachya. We produced pretreated solids characterized by up to 51.3% ± 1.7% cellulose, a significant increase from 25.6% ± 1.3% in untreated fibers. A delignification yield of as high as 60.7%, and hemicellulose removal of as high as 86.1% were also achieved in the current study. The obtained cellulose could be completely converted to glucose via enzymatic hydrolysis within 24 h. The lignin fractions obtained were of high purity, with sugar contamination of only 1.22% w/w and ashes below 1% w/w in most samples. Finally, up to 29.1% ± 0.4% hemicellulose was recovered as a separate product, whose proportion of oligomers to total sugars was 69.9% ± 3.0%. To the best of our knowledge, this is the first report in which Salicornia fibers are shown to be a suitable feedstock for organosolv biomass fractionation. These results expand the portfolio of biomass sources for biorefinery applications.An organosolv method was developed for the fractionation of fibers of a halophyte plant in a biorefinery approach. Salicornia dolichostachya was used as raw material allowing the production of cellulose, hemicellulose, and lignin fractions. 相似文献
8.
9.
Despoina Giannopoulou Maria G. Grammatikopoulou Dimitrios Poulimeneas Maria Maraki Leonidas Dimitrakopoulos Maria Tsigga 《Journal of immigrant and minority health / Center for Minority Public Health》2017,19(2):333-340
Previous studies have shown that the diets of migrant populations are of poor quality; however, studies on populations remaining in one geographical region as a minority after an acute population movement are scarce. Therefore, the aim of the present study was to assess dietary intake and growth of Greek minority adolescents in Turkey. Anthropometric measurements and dietary assessment were performed in 103 Greek Orthodox students (aged 10–19 years old) of three minority schools in Istanbul. Prevalence of overweight and obesity according to the WHO growth charts was 39.8 %. Accordingly, 40 % of the sample exhibited excess body fat. Dietary intakes of protein, carbohydrate, fiber, vitamins E and D, folic acid and calcium were inadequate, while energy, total fat and iron intakes were considered adequate. Our results indicate that Greek minority adolescents living in Turkey have similar weight status compared to their counterparts in Greece, but greater body fat than Turkish coevals, while being at risk of several nutrient inadequacies. 相似文献
10.