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31.
Contact allergy in relation to hand eczema and atopic diseases in north Norwegian schoolchildren 总被引:3,自引:0,他引:3
Dotterud LK, Falk ES. Contact allergy in relation to hand eczema and atopic diseases in north Norwegian schoolchildren. Acta Psediatr 1995;84:402–6. Stockholm. ISSN 0803–5253
Patch testing was carried out in 424 schoolchildren (223M, 201F), aged 7–12 years, in northern Norway. In 99 (23.3%) of these children, one or more allergic patch test reactions were demonstrated; 30 children reacted to two and 6 to three or more substances; 53 irritant reactions were recorded in 33 (7.8%) of those tested. From a total of 144 positive tests, the most common allergen was nickel (14.9%), followed by cobalt (5.7%), kathon CG (5.2%), lanolin (1.7%) and neomycin (1.4%). Both allergic and irritant reactions were found twice as frequently in girls as in boys. Positive patch tests were significantly more frequent in atopic (28.8%) than in non–atopic (17.9%) children, being most pronounced in atopic girls (37.4%). Hand eczema was reported to have occurred or to be present in 6.5% of cases. Twenty–nine of 36 children reporting hand eczema participated in the clinical examination. Altogether 15 (3.5%) children had hand eczema at the time of the clinical examination but 12 of these children had no previous history of hand eczema. In 14 of these 15 subjects, the eczema was localized to the back of the hands, with 13 having atopic dermatitis. In 4 of these 15 children, an allergic patch test reaction was found; however, in only 2 of these 4 was the test considered to be clinically relevant for the diagnosis allergic hand eczema. In conclusion, irritant hand eczema may occur in early childhood and is most prevalent in children with atopic dermatitis 相似文献
Patch testing was carried out in 424 schoolchildren (223M, 201F), aged 7–12 years, in northern Norway. In 99 (23.3%) of these children, one or more allergic patch test reactions were demonstrated; 30 children reacted to two and 6 to three or more substances; 53 irritant reactions were recorded in 33 (7.8%) of those tested. From a total of 144 positive tests, the most common allergen was nickel (14.9%), followed by cobalt (5.7%), kathon CG (5.2%), lanolin (1.7%) and neomycin (1.4%). Both allergic and irritant reactions were found twice as frequently in girls as in boys. Positive patch tests were significantly more frequent in atopic (28.8%) than in non–atopic (17.9%) children, being most pronounced in atopic girls (37.4%). Hand eczema was reported to have occurred or to be present in 6.5% of cases. Twenty–nine of 36 children reporting hand eczema participated in the clinical examination. Altogether 15 (3.5%) children had hand eczema at the time of the clinical examination but 12 of these children had no previous history of hand eczema. In 14 of these 15 subjects, the eczema was localized to the back of the hands, with 13 having atopic dermatitis. In 4 of these 15 children, an allergic patch test reaction was found; however, in only 2 of these 4 was the test considered to be clinically relevant for the diagnosis allergic hand eczema. In conclusion, irritant hand eczema may occur in early childhood and is most prevalent in children with atopic dermatitis 相似文献
32.
Evidence against stabilization of the transition state oxyanion by a pKa-perturbed RNA base in the peptidyl transferase center
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Parnell KM Seila AC Strobel SA 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(18):11658-11663
The crystal structure of the ribosomal 50S subunit from Haloarcula marismortui in complex with the transition state analog CCdA-phosphate-puromycin (CCdApPmn) led to a mechanistic proposal wherein the universally conversed A2451 in the ribosomal active site acts as an "oxyanion hole" to promote the peptidyl transferase reaction [Nissen, P., Hansen, J., Ban, N., Moore, P.B., and Steitz, T.A. (2000) Science 289, 920-929]. In the model, close proximity (3 A) between the A2451 N3 and the nonbridging phosphoramidate oxygen of CCdApPmn suggested that the carbonyl oxyanion formed during the tetrahedral transition state is stabilized by hydrogen bonding to the protonated A2451 N3, the pKa of which must be perturbed substantially. We characterize the contribution of the putative hydrogen bond between the N3 of A2451 and the nonbridging phosphoramidate oxygen by using chemical protection and peptidyl transfer inhibition assays. If this putative hydrogen bond makes a significant thermodynamic contribution, then CCdApPmn-binding affinity to the 50S ribosomal subunit should be strongly pH-dependent, with affinity increasing as the pH is lowered. We report that CCdApPmn binds 50S ribosomes with essentially equal affinity at all pH values between 5.0 and 8.5. These data argue against a mechanism for peptidyl transfer in which a residue with near neutral pKa stabilizes the transition-state oxyanion, at least to the extent that CCdApPmn accurately mimics the transition state. 相似文献
33.
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35.
Changing use of hospital beds by the elderly 总被引:1,自引:0,他引:1
36.
W B Mill L A Palmer-Hanes J A Purdy T W Tillack E H Reinhard V Loeb D N Parnell M A Penkoske K O Franssila 《Cancer》1977,40(6):2896-2904
A retrospective analysis of 116 primary cases of stage I, II and III-A Hodgkin's disease demonstrated 27 failures, fourteen confirmed by biopsy. Twenty of the 27 (74%) were in lymph node areas only and seven had extranodal extensions. The most frequent site of failure was the hilar nodes and contiguous lung. The majority of failures (78%) occurred within 30 months of treatment and the cause of failure determined in 23 (85%), sixteen of which were due to technical errors of irradiation. Analysis of the dosimetry in the mediastinal, hilar nodes and contiguous lung failures revealed three factors which may have contributed to a low dose. These factors are: 1) the equivalent square, 2) off-axis beam diminution, and 3) the anteroposterior dose profile. Combined radiation therapy and chemotherapy was more effective than either modality alone in the treatment of these failures. 相似文献
37.
Madhok AB Chandrasekran A Parnell V Gandhi M Chowdhury D Pahwa S 《Clinical and diagnostic laboratory immunology》2005,12(5):563-565
The human thymus is required for establishment of a T-cell pool in fetal life, but postnatal thymectomy is not known to cause immunodeficiency. T-cell emigration from thymus (thymic recent emigrants [TRECs]) is a continuous thymic-dependent process. We studied TREC levels pre- and post-partial thymectomy in children undergoing cardiac surgery. TRECs were quantitated by real-time PCR in peripheral blood lymphocytes of 24 children (0 to 12 years). TREC values were 47916 +/- 9271 pre-partial thymectomy and 33157 +/- 8479 post-partial thymectomy in 11 paired patients (P = 0.014). Interval between pre- and post-partial thymectomy was 8.8 days +/- 5.8 days. Another group of 8 children had 30384 +/- 9748 TRECs 16 days to 6 years post-partial thymectomy. There was a significant drop in TREC values post-partial thymectomy in the immediate postoperative period compared to prethymectomy TREC levels. While decreased thymic output may persist, the long-term implications were not evaluated in this patient population. 相似文献
38.
Levy JI Welker-Hood LK Clougherty JE Dodson RE Steinbach S Hynes HP 《Environmental health : a global access science source》2004,3(1):13
Background
Children in urban public housing are at high risk for asthma, given elevated environmental and social exposures and suboptimal medical care. For a multifactorial disease like asthma, design of intervention studies can be influenced by the relative prevalence of key risk factors. To better understand risk factors for asthma morbidity in the context of an environmental intervention study, we conducted a detailed baseline evaluation of 78 children (aged 4–17 years) from three public housing developments in Boston. 相似文献39.
AIMS: To examine the adequacy of calcium intake in relation to current recommendations, demographic differences in calcium intake and dietary sources in the New Zealand population. METHODS: 24-hour diet recall and qualitative food frequency data from the 1997 New Zealand National Nutrition Survey (NNS97) were used. RESULTS: No age-gender subgroups had median intakes meeting the latest (1998) US recommendations. Women's median intakes failed to meet even the considerably lower 1990 Australian recommendations. 20% of New Zealanders and one in four women had intakes below the UK Estimated Average Requirements for calcium. Intakes below the UK Lower Reference Nutrient Intake (the level at which the risk of deficiency is virtually 100%) were common (15-20%) among women aged 15-18 years, those living in the most deprived areas or Maori. Milk and milk products were the major sources of the nation's calcium intake. CONCLUSION: Although other factors such as genetics, hormonal status, vitamin D status and exercise influence skeletal health, adequate calcium intakes are important in minimizing bone loss. A reduction in the proportion of New Zealanders with inadequate calcium intakes will most readily be achieved if more people meet the milk products Dietary Guideline (minimum of two servings daily). Health professionals can play an important role in raising perceptions of the benefits of adequate calcium intakes, promoting the milk products Dietary Guideline, and emphasising that lower fat diets can include adequate calcium through use of reduced fat milk products. 相似文献
40.
AIMS: To describe the development and use of the methodologies in the 1997 New Zealand National Nutrition Survey (NNS97). METHODS: NNS97 was a voluntary cross-sectional population survey conducted over a twelve month period on 4,636 non-institutionalized urban and rural New Zealand residents aged fifteen years and older. Survey data were collected in the participants' home and included: a self-administered qualitative food frequency questionnaire, including questions on food preparation habits; a three-pass 24-hour diet recall; interviewer-administered questions on diet supplement use, barriers to dietary change and participant perception of household food security; physical measurements including weight, height, three circumferences, two skinfolds and elbow breadth; blood pressure; and a blood sample to determine cholesterol and iron status. RESULTS: New methodologies developed for NNS97 included a computer based interview system, probability analyses for estimating prevalence of inadequate intake of selected nutrients, determination of iron status by both dietary and biochemical assessment, assessments of dietary supplement use and food security. A full range of quality control procedures at each stage of the data collection were also initiated. CONCLUSION: NNS97 has improved on previous New Zealand national nutrition survey methodologies, particularly with direct data capture and rigorous quality control procedures used in the collection of survey data. 相似文献