全文获取类型
收费全文 | 941篇 |
免费 | 65篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 43篇 |
妇产科学 | 50篇 |
基础医学 | 224篇 |
口腔科学 | 10篇 |
临床医学 | 89篇 |
内科学 | 250篇 |
皮肤病学 | 19篇 |
神经病学 | 29篇 |
特种医学 | 17篇 |
外科学 | 53篇 |
综合类 | 11篇 |
预防医学 | 93篇 |
眼科学 | 7篇 |
药学 | 66篇 |
肿瘤学 | 40篇 |
出版年
2022年 | 6篇 |
2021年 | 16篇 |
2020年 | 11篇 |
2019年 | 21篇 |
2018年 | 22篇 |
2017年 | 14篇 |
2016年 | 22篇 |
2015年 | 14篇 |
2014年 | 21篇 |
2013年 | 38篇 |
2012年 | 50篇 |
2011年 | 38篇 |
2010年 | 30篇 |
2009年 | 22篇 |
2008年 | 39篇 |
2007年 | 43篇 |
2006年 | 48篇 |
2005年 | 48篇 |
2004年 | 47篇 |
2003年 | 28篇 |
2002年 | 27篇 |
2001年 | 31篇 |
2000年 | 27篇 |
1999年 | 21篇 |
1998年 | 5篇 |
1997年 | 9篇 |
1996年 | 12篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 13篇 |
1991年 | 25篇 |
1990年 | 15篇 |
1989年 | 12篇 |
1988年 | 16篇 |
1987年 | 15篇 |
1986年 | 16篇 |
1985年 | 13篇 |
1984年 | 11篇 |
1983年 | 8篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1975年 | 6篇 |
1974年 | 8篇 |
1973年 | 16篇 |
1972年 | 5篇 |
1970年 | 8篇 |
1968年 | 6篇 |
1966年 | 5篇 |
排序方式: 共有1008条查询结果,搜索用时 0 毫秒
101.
F Colizzo M J Krantz J E Fish A T Hastie 《Journal of toxicology and environmental health》1992,35(4):221-234
The investigation sought to identify alterations of specific ciliated epithelial surface components after exposure to formaldehyde (HCHO) levels that decrease respiratory ciliary function. Bovine tracheae were reacted with an analog of N-hydroxysuccinimidobiotin to label epithelial surface-accessible components before exposure to HCHO. The tracheae were then exposed to 0, 16, 33, and 66 micrograms HCHO/cm2 epithelial surface for 30 min. Cilia were isolated from the epithelium, separated into membrane and internal axonemal portions, analyzed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and either stained to detect proteins or transblotted to detect biotin-labeled components. Densitometric analysis of axoneme proteins showed a decrease in the total amount extracted with increased HCHO concentration, including axoneme-specific proteins, dynein, and tubulin. However, biotinylated proteins in the axoneme fractions proportionately increased. Membrane fractions showed little change in protein with increasing HCHO concentration. The majority of these is not biotin-labeled and thus not surface-accessible components. Biotinylated material in the membrane fractions showed a significant decrease with increased HCHO concentration, particularly of bands at 92, 98, and 105 kD. These data suggest that increasing HCHO exposure reduces both extractable ciliary axonemes and detergent-soluble surface components, possibly by stabilizing respiratory epithelial membranes. This process apparently strengthens association of certain surface components with the internal axoneme, thereby reducing subsequent solubilization in detergent. 相似文献
102.
Li Y Steinberg AG Bain L Yaeger D Bieler A Ewing R Kaimal G Krantz I 《American journal of medical genetics. Part A》2007,(14):1546-1553
We report on the development of a Genetic Attitude Assessment Tool (GAAT) to measure parental attitudes in contemplating genetic testing for childhood hearing loss, and to examine the differences in assessments made before and after genetic counseling. The GAAT tool was administered to a convenient sample of 119 parents of children with bilateral sensorineural hearing loss. The respondents completed the survey either before (n = 77) or after (n = 42) genetic counseling. Exploratory Factor Analysis was applied to identify and quantify the underlying psychosocial structure. Our results showed the validated 54-item GAAT instrument contains six subscales: (1) "test intention," (2) "beliefs in non-genetic causes of hearing loss," (3) "deferral of decision to undergo genetic testing," (4) "appropriate use of genetic testing results," (5) "beliefs in the benefits," and (6) "concerns about stigma." The respondents who answered the survey after genetic counseling had higher "test intention" (P = 0.017) and endorsed to a greater extent "beliefs in the benefits" (P < 0.001). They believed to a lesser extent that childhood hearing loss was due to "non-genetic causes" (P < 0.001) and were less inclined to prefer "decision deferral" (P = 0.031). Respondents who themselves had a hearing loss expressed a significantly weaker belief in "non-genetic causes" of hearing loss (P < 0.0001). In conclusion the validated GAAT instrument is responsive to changes in parental attitudes after genetic counseling. The GAAT may be used to monitor parental attitudes serially, to further understand how parental attitudes change from pre genetic counseling, post genetic counseling, to post test result disclosure. 相似文献
103.
Human bocavirus, a respiratory and enteric virus 总被引:3,自引:0,他引:3
Vicente D Cilla G Montes M Pérez-Yarza EG Pérez-Trallero E 《Emerging infectious diseases》2007,13(4):636-637
In Spain, human bocavirus (HBoV) was detected in 48 (9.1%) of 527 children with gastroenteritis at similar frequency as for children with respiratory illness (40/520, 7.7%). Fecal excretion adds new concern about the transmission of HBoV. To our knowledge, this report is the first to document HBoV in human feces. 相似文献
104.
Milena Ferro Gabriella Macchia Alessia Re Milly Buwenge Marica Ferro Mariangela Boccardi Vincenzo Picardi Anna Ianiro Eleonora Arena Alice Zamagni Eleonora Farina Savino Cilla Vincenzo Valentini Alessio Giuseppe Morganti Francesco Deodato 《Journal of Geriatric Oncology》2021,12(3):441-445
ObjectivesTo assess the feasibility and safety of a repeated SHort course Accelerated RadiatiON therapy (SHARON) regimen in the palliative setting of Head and Neck (H&N) cancer in older adults.Material and MethodsPatients with histological confirmed H&N cancers, age ≥ 80 years, expected survival >3 months, and Eastern Cooperative Oncology Group (ECOG) performance status of ≤3 were enrolled. Patients were treated in cohorts of six patients: a total dose of 20 Gy was delivered in 2 consecutive days with a twice-daily fractionation (5 Gy per fraction) and at least 8-h interval. If no Grade 3 toxicity was registered, a second enrollment started with another cohort of six patients to whom were administered two cycles (total dose of 40 Gy). The primary endpoint was to evaluate the feasibility of the two cycles of treatment. Secondary endpoints were evaluation of symptoms control rate, symptoms-free survival (SFS), and Quality of Life (QoL) scores.ResultsSeventeen consecutive patients (median age: 85 years) were treated. Nine patients were treated with one cycle and 8 patients with two cycles. No G3 toxicity was reported in either cohort. With a median follow-up time of 4 months, 3-month SFS in the first and second cohorts was 83.3%, and 87.5%, respectively. The overall palliative response rate was 88%. Among 13 patients reporting pain, 8 (61.5%) showed an improvement or resolution of their pain.ConclusionRepeated short course accelerated radiotherapy in a palliative setting of H&N cancers is safe and well-tolerated in older adults. 相似文献
105.
Cognitive hypotheses about depression derived from the reformulated learned helplessness theory were tested in students' attributional analyses of the causes of their own recent stressful life events. Results supported the hypothesis that depression as measured by the Beck Depression Inventory is associated with certain causal cognitions, and these cognitions were predictive of the intensity, chronicity, and generality of depression 2 months after the initial testing. Cognitions especially related to depression emphasized perceived low control over causes of events and globality of the causes. Attribution theory-based predictions that internal locus of causality and stability would be related to naturally occurring depression were not supported. In addition, there were no sex differences in attributions. While the results support the possible role of cognitive mediators between life events and depressive reactions, they also suggest that depression-related causal analyses may vary across situations and populations.This article was based on information presented at the 12th Annual Meeting of the Association for the Advancement of Behavior Therapy, Chicago, November 1978. The authors wish to thank J. Arthur Woodward for his statistical assistance. 相似文献
106.
Eva Hellström-Lindberg Robert Negrin Richard Stein Sanford Krantz Greger Lindberg James Vardiman Åke Öst & Peter Greenberg 《British journal of haematology》1997,99(2):344-351
Previous studies have shown that approximately 40% of patients with myelodysplastic syndrome (MDS) and anaemia respond to treatment with human recombinant granulocyte-CSF (G-CSF) plus erythropoietin (epo). The present study was designed to investigate pre-treatment variables for their ability to predict erythroid responses to this treatment. 98 patients with MDS (30 RA, 31 RARS, 32 RAEB, five RAEB-t) were treated with a combination of G-CSF (0.3–3.0 μg/kg/d, s.c.) and epo (60–300 U/kg/d, s.c.) for at least 10 weeks. Minimum criteria for erythroid response was a 100% reduction of red blood cell (RBC) transfusion need or an increase in haemoglobin level of 1.5 g/dl. 35 patients (36%) showed responses to treatment. Medium duration of response was 11–24 months. In multivariate analysis, serum erythropoietin levels and initial RBC-transfusion need retained high statistical significance ( P < 0.01). Using pre-treatment serum epo levels as a ternary variable (< 100, 100–500 or > 500 U/l) and RBC transfusion need as a binary variable (< 2 or 2 units per month), the analysis provided a predictive score for erythroid response. This score divided patients into three groups: one group with a high probability of erythroid responses (74%), one intermediate group (23%) and one group with poor responses to treatment (7%). This predictive scoring system could be used in decisions regarding use of these cytokines for treating the anaemia of MDS, both for defining patients who should not be given the treatment and for selecting patients for inclusion in prospective trials. 相似文献
107.
108.
109.
110.