全文获取类型
收费全文 | 505篇 |
免费 | 32篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 32篇 |
妇产科学 | 11篇 |
基础医学 | 52篇 |
口腔科学 | 9篇 |
临床医学 | 31篇 |
内科学 | 78篇 |
皮肤病学 | 19篇 |
神经病学 | 17篇 |
特种医学 | 138篇 |
外科学 | 66篇 |
综合类 | 20篇 |
预防医学 | 21篇 |
眼科学 | 6篇 |
药学 | 22篇 |
肿瘤学 | 27篇 |
出版年
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 14篇 |
2014年 | 9篇 |
2013年 | 12篇 |
2012年 | 6篇 |
2011年 | 15篇 |
2010年 | 24篇 |
2009年 | 30篇 |
2008年 | 16篇 |
2007年 | 29篇 |
2006年 | 24篇 |
2005年 | 24篇 |
2004年 | 21篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 17篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 20篇 |
1997年 | 37篇 |
1996年 | 21篇 |
1995年 | 22篇 |
1994年 | 16篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 8篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 15篇 |
1986年 | 9篇 |
1985年 | 10篇 |
1984年 | 5篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 7篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1974年 | 1篇 |
排序方式: 共有550条查询结果,搜索用时 15 毫秒
51.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6
Background
To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.Methods
36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.Results
There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)Conclusion
Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone. 相似文献52.
Background In this study two different quality of life items are compared, and correlation of patient satisfaction with preoperative
and postoperative symptoms after laparoscopic Nissen fundoplication (LNF) for chronic gastroesophageal reflux disease is evaluated.
Materials and Methods Between December 2002 and December 2004, 60 patients with a diagnosis of chronic gastroesophageal reflux disease scheduled
for laparoscopic Nissen fundoplication were recruited prospectively and volunteered to participate in this study. Patients
underwent endoscopy, and their disease-specific symptoms were scored on a scale. Quality of life was measured preoperatively
and in the first and sixth postoperative months with two questionnaires: Short Form-36 (SF 36) (preoperatively) and the Gastroesophageal
Reflux Disease—Health-Related Quality of Life (GERD-HRQL) (postoperatively).
Results In more than 90% of the patients, typical symptoms (regurgitation and pyrozis) were controlled postoperatively (p < 0.001). In the first postoperative month, however, dysphagia (early dysphagia) was seen in 46 (76%) patients, whereas in
the sixth postoperative month (late dysphagia) its incidence decreased to only 2 (3.3%) patients. Similarly, in the first
postoperative month 42 (70%) patients had gas bloating, but the incidence of this symptom decreased to 26 (43.3%) patients
by the sixth month (p = 0.01). The quality-of-life measurements obtained from both SF 36 and GERD-HRQL showed that quality of life of the patients
improved significantly in the related domain of each item after surgery (p < 0.001).
Conclusions Laparoscopic Nissen fundoplication is an effective operation that controls the typical symptoms and improves the quality of
life of patients, but new-onset symptoms affect postoperative well-being. For closer evaluation of the benefits of the operation,
we need new questionnaires that comprehensively evaluate the symptom spectrum of GERD both preoperatively and postoperatively. 相似文献
53.
54.
Paulo CJL Santos Renata AG Soares Diogo BG Santos Raimundo M Nascimento George LLM Coelho José C Nicolau José G Mill José E Krieger Alexandre C Pereira 《BMC medical genetics》2011,12(1):13
Background
Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population. 相似文献55.
Prof. Dr. rer. nat. E. Spörl N. Terai M. Haustein AG. Böhm F. Raiskup-Wolf L.E. Pillunat 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2009,106(6):512-520
Aim
Several methods permit the measurement of geometric parameters of the cornea, but until now biomechanical conditions of the cornea have been ignored (e.g. in refractive corneal surgery). Besides the geometric condition, biomechanical properties of the cornea have been shown to influence applanation measurement of intra-ocular pressure (IOP) and epidemiological studies have identified corneal thickness as an independent risk factor for the development and progression of glaucoma. The aim of this investigation was to characterize the biomechanical properties of the cornea using the ocular response analyzer (ORA).Methods
The ocular response analyzer (ORA) is a new method available for non-contact measurement of the biomechanical properties of the cornea. We evaluated the reproducibility of measurements, the difference between static and dynamic factors and the impact of independent factors (e.g. IOP, age, CCT, swelling of the cornea) on 2,500 measurements of corneal hysteresis (CH) and corneal resistance factor (CRF).Results
In a large sample size we observed changes in CH and CRF after refractive surgery procedures (LASIK, UV-A cross-linking, keratoplasty) and in other corneal disorders (keratoconus, corneal dystrophies).Conclusions
CRF and CH changes may reflect structural changes of the cornea. Thus, the ORA provides valuable information for a better understanding and characterization of the biomechanical condition of the cornea, especially with regard to diseases such as keratoconus and glaucoma. 相似文献56.
Background Bacterial overgrowth may cause cobalamin deficiency through competition for dietary cobalamin in the small intestine. The objective of this study was to prospectively determine the prevalence of small bowel bacterial overgrowth in patients with documented cobalamin deficiency in a tertiary referral centre.
Methods Patients identified with cobalamin deficiency underwent diagnostic investigations including: Endoscopy (with gastric antrum, gastric body and duodenal biopsies and duodenal aspirate),14 C-D-Xylose breath test, intrinsic factor antibody, anti-endomysial antibody and red cell folate level. 'Definite' small bowel bacterial overgrowth was defined as either a positive 14 C-D-Xylose breath test or > 100 000 CFU/mL of culture of duodenal aspirate. 'Suspected' small bowel bacterial overgrowth was defined as an elevated red cell folate in the absence of supplemental folate therapy.
Results Over a 2-year period, 62 patients with cobalamin deficiency were identified, of whom, 26 (42%) had 'definite' small bowel bacterial overgrowth, whilst a further nine (15%) had 'suspected' small bowel bacterial overgrowth. Nineteen (31%) had pernicious anaemia, and no cause for cobalamin deficiency could be found in eight (13%) patients. The diagnosis found in the remaining patients included coeliac disease (4), Crohn's Disease (1), gastric resection (2), vegan (2), homozygotes of the MTHFR gene (C677T) mutation (2), and one had enteropathy associated with common variable immunodeficiency (CVID). 'Definite' small bowel bacterial overgrowth was found to coexist with nine of the 19 cases of pernicious anaemia, two coeliac subjects, one CVID enteropathy and one patient with the MTHFR gene mutation.
Conclusion Small bowel bacterial overgrowth is commonly associated with cobalamin deficiency. 相似文献
Methods Patients identified with cobalamin deficiency underwent diagnostic investigations including: Endoscopy (with gastric antrum, gastric body and duodenal biopsies and duodenal aspirate),
Results Over a 2-year period, 62 patients with cobalamin deficiency were identified, of whom, 26 (42%) had 'definite' small bowel bacterial overgrowth, whilst a further nine (15%) had 'suspected' small bowel bacterial overgrowth. Nineteen (31%) had pernicious anaemia, and no cause for cobalamin deficiency could be found in eight (13%) patients. The diagnosis found in the remaining patients included coeliac disease (4), Crohn's Disease (1), gastric resection (2), vegan (2), homozygotes of the MTHFR gene (C677T) mutation (2), and one had enteropathy associated with common variable immunodeficiency (CVID). 'Definite' small bowel bacterial overgrowth was found to coexist with nine of the 19 cases of pernicious anaemia, two coeliac subjects, one CVID enteropathy and one patient with the MTHFR gene mutation.
Conclusion Small bowel bacterial overgrowth is commonly associated with cobalamin deficiency. 相似文献
57.
58.
Aim
Right ventricular (RV) systolic function in patients with hypertensive heart disease (HHD) is not well characterised. The primary aim of this study was to assess the systolic function of the right ventricle in patients with HHD using tricuspid annular-plane systolic excursion (TAPSE).Methods
The study was cross-sectional in design and carried out in Kano, Nigeria. Patients were recruited if they had HHD on echocardiography and were at least 15 years of age. Patients with other cardiac pathologies such as ischaemic and valvular heart diseases were excluded. Patients were considered to have abnormal RV systolic function if they had reduced values of TAPSE (< 15 mm). A p-value of < 0.05 was considered statistically significant.Results
A total of 186 patients were serially recruited over seven months. Of these, 131 (70.4%) had normal RV systolic function (group 1) and 55 patients (29.6%) had abnormal function (group 2). Group 2 patients were older (p = 0.002) and had a higher prevalence of peripheral oedema (p = 0.002), moderate to severe dyspnoea, higher heart rate and lower left ventricular ejection fraction (p < 0.001). Atrial arrhythmias were also more prevalent among group 2 patients (p < 0.05). The best correlate to TAPSE was the septal mitral annularplane systolic excursion (r = +0.541, p < 0.001). Several variables such as age predicted the presence of reduced TAPSE.Conclusion
The study found that almost one-third of patients with HHD in Kano had RV systolic dysfunction as defined by reduced TAPSE, and these patients had a greater prevalence of factors associated with morbidity and mortality. 相似文献59.
Vorstand und AG Angeborene Herzfehler/Kinderherzchirurgie der DGTHG 《The Thoracic and cardiovascular surgeon》2006,54(2):73-77
The "Working Group for Congenital Heart Surgery and Pediatric Heart Surgery" of the German Society for Thoracic and Cardiovascular Surgery (GSTCVS) has analysed and recommended structures for congenital heart surgery departments in Germany. The document was worked out according to a similar paper approved earlier by the European Association for Cardio-thoracic Surgery (EACTS). The "Working Group" unifies the majority of cardiac surgeons involved in congenital heart surgery in Germany. Current structures of cardiac centers vary. Therefore the aim of this document is to elucidate additional structural needs for both highly specialized institutions and those for standard care. Specialized centers should allow for treatment of newborns and adult patients with congenital heart disease, include implementation of assist devices and transplantation, possess research facilities and ensure highest standards of education and training. Standard care units do not necessarily need to cater for the above mentioned spectrum. However, the evaluation of quality of care should be given priority in all centers involved in care of patients with congenital heart disease. Data acquisition and transfer must be guaranteed to both the GSTCVS and EACTS in order to ensure national and international comparison of surgical results. This may also give further guidance for improved patient care. 相似文献
60.
Oxidative stress and antioxidant status in elderly diabetes mellitus and glucose intolerance patients 总被引:5,自引:0,他引:5
Atli T Keven K Avci A Kutlay S Turkcapar N Varli M Aras S Ertug E Canbolat O 《Archives of gerontology and geriatrics》2004,39(3):269-275
Increased oxidative stress and impaired anti-oxidant defense have been suggested as contributory factors for initiation and progression of complications in diabetes mellitus. Aging itself has been shown to be along with increased oxidative stress and lower anti-oxidant defense. We aimed at investigating oxidative stress and anti-oxidant enzymes in 61 elderly subjects. Fifteen healthy individuals (group 1, mean age 72.2 +/- 5.13), 13 glucose intolerant patients (group 2, mean age 71.7 +/- 4.9), 19 patients with type 2 diabetes mellitus (T2DM) without any complication (group 3, mean age 70.0 +/- 6.0), and 14 patients with T2DM with at least one complication (group 4, mean age 69.8 +/- 4.7) were included in the study. Whilst plasma levels for malondialdehyde (MDAP) and erythrocyte malondialdehyde (MDAE) were measured as markers of oxidative stress, activity of erythrocyte superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), and catalase (CAT) were taken as markers of oxidative defense system. MDAP level was significantly elevated in group 4 (P = 0.001). MDAE was elevated in patients with T2DM, particularly in group 4, however, the difference between the groups was of borderline significance (P = 0.07). Whilst CAT was elevated in groups 3 and 4 compared to control subjects (P = 0.025 and 0.002, respectively), no difference was found for SOD between the groups. GSH-Px activity was found to be increased in groups 2, 3 and 4, it did not reach statistical significance (P = 0.106). There were significant correlations between CAT and MDAE (P < 0.0001, r = 0.056) and MDAP (P = 0.016, r = 0.306). These results suggest that there was an increased oxidative stress in elderly diabetics, however, this is not due to reduced erythrocyte antioxidant defense potential but, rather, increased free radical production possibly due to hyperglycemia. 相似文献