首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1227篇
  免费   66篇
  国内免费   5篇
耳鼻咽喉   20篇
儿科学   20篇
妇产科学   24篇
基础医学   165篇
口腔科学   37篇
临床医学   91篇
内科学   288篇
皮肤病学   10篇
神经病学   115篇
特种医学   23篇
外科学   156篇
综合类   8篇
预防医学   187篇
眼科学   8篇
药学   89篇
中国医学   4篇
肿瘤学   53篇
  2023年   13篇
  2022年   11篇
  2021年   46篇
  2020年   17篇
  2019年   29篇
  2018年   62篇
  2017年   38篇
  2016年   33篇
  2015年   37篇
  2014年   34篇
  2013年   59篇
  2012年   76篇
  2011年   112篇
  2010年   54篇
  2009年   24篇
  2008年   90篇
  2007年   79篇
  2006年   69篇
  2005年   73篇
  2004年   47篇
  2003年   38篇
  2002年   45篇
  2001年   15篇
  2000年   10篇
  1999年   8篇
  1998年   4篇
  1992年   7篇
  1991年   4篇
  1990年   7篇
  1989年   7篇
  1988年   5篇
  1987年   4篇
  1986年   13篇
  1985年   4篇
  1983年   4篇
  1979年   8篇
  1978年   4篇
  1977年   3篇
  1976年   5篇
  1975年   7篇
  1974年   4篇
  1973年   10篇
  1972年   13篇
  1971年   9篇
  1970年   5篇
  1969年   6篇
  1968年   4篇
  1967年   3篇
  1966年   7篇
  1965年   3篇
排序方式: 共有1298条查询结果,搜索用时 15 毫秒
1.
2.
B Iványi  G Mohácsi  S Sonkodi  J Ormos 《Orvosi hetilap》1992,133(38):2431-2434
IgG lambda type of monoclonal gammopathy and thin basement membrane nephropathy were established in a middle-aged man examined because of persistent haematuria, lambda light-chain proteinuria and moderately diminished renal function. A 10% level of plasmocytosis was verified by bone-marrow aspiration. The more than 6-year follow-up showed the gammopathy to be benign. The thin basement membrane nephropathy was verified by electronmicroscopic analysis of renal tissue obtained by percutaneous renal biopsy: lamina densa of the glomerular capillaries thinned to 30-100 nm. In spite of the usually good outcome of thin basement membrane nephropathy, in this case it was accompanied by glomerular sclerosis, subsequent destruction of nephrons, hypertensive vascular alterations and a clinical deterioration of the renal function after 4 years. A rebiopsy excluded the possible complications (amyloidosis, non-amyloid immunoglobulin nephropathy, cylinder nephropathy, etc) of light-chain proteinuria.  相似文献   
3.
A silver staining technique for nucleolar organizer regions (NORs) has been applied to bone marrow biopsies of various types of acute and chronic leukaemias. This method could be easily evaluated on resin-embedded bone marrow obtained from acute lymphocytic leukaemia (n = 12), acute myelogenous (n = 16), chronic lymphocytic (n = 16) and chronic granulocytic (n = 20) leukaemia. A significant difference (p < or = 0.1) was only found between the AgNOR numbers in nuclei of lymphocytes from acute and chronic leukaemia (mean of 1.23 to 1.40 and 1.58) and those of cells from acute and chronic myelogenous leukaemia (from a mean of 5.00 to 9.17 per nucleus). However, no significant difference was observed among cells of various types of acute and chronic myelogenous leukaemias, despite of their markedly higher staining intensity and proliferative activity. The greatest mean of AgNOR numbers was counted in monoblasts of acute myelomonocytic leukaemia. It is suggested, that higher AgNOR counts in nuclei of more malignant leukaemic cells are in parallel with their mitotic activity and could be related to their elevated cell turn-over.  相似文献   
4.
Merkel cell carcinoma was diagnosed in a 79-year-old Caucasian woman. The tumour was localised to the upper lip and was in stage T2. After successful cryosurgery and a 7-year tumour-free period, a new tumour developed in her palatine tonsil. Histologically and immunohistochemically, this resembled the tumour in the lip. The regional lymph nodes were devoid of metastasis. The paraffin-embedded material of the two tumours and the unaffected lymphatic tissue were analysed with DNA microarrays for comparative genomic hybridisation to assess the genetic relationship of the tumours. In both tumours, regions on 2p and 10p were commonly over-represented, while 41 regions on chromosomes 1–4, 6, 8–9, 11 and 14–22 were commonly under-represented. Chromosomes 1, 3, 4, 16–18 and X were most frequently involved in the DNA losses. In gene copy numbers in the two tumours, 31 chromosome locations were found to be differently affected. The partly similar and partly different molecular patterns indicated a genetic relationship between the tumours and excluded the possibility that the tonsillar tumour was a metastasis. The findings suggest that a genetically altered field was the reason for the development of the tonsillar cancer; thus, it can be regarded pathogenetically as a second field tumour.  相似文献   
5.
We report the results of reduced-intensity conditioning allogeneic stem cell transplantation (allo-RIC) in patients with advanced Hodgkin lymphoma (HL). Forty patients with relapsed or refractory HL were homogeneously treated with an RIC protocol (fludarabine 150 mg/m(2) intravenously plus melphalan 140 mg/m(2) intravenously) and cyclosporin A and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Twenty-one patients (53%) had received >2 lines of chemotherapy, 23 patients (58%) had received radiotherapy, and 29 patients (73%) had experienced treatment failure with a previous autologous stem cell transplantation. Twenty patients (50%) were allografted in resistant relapse, and 38 patients received hematopoietic cells from an HLA-identical sibling. Five patients (12%) died from early transplant-related mortality (before day +100 after allo-RIC). One-year transplant-related mortality was 25%. Acute GVHD developed in 18 patients (45%). Chronic GVHD developed in 17 (45%) of the 31 evaluable patients. The response rate 3 months after the allo-RIC was 67% (21 [52%] complete remissions and 6 [15%] partial remissions). Eleven patients received donor lymphocyte infusions (DLIs) for disease relapse. The response rate after DLI was 54% (3 complete remissions and 3 partial remissions). Overall survival (OS) and progression-free survival (PFS) were 48% +/- 10% and 32% +/- 10% at 2 years, respectively. Refractoriness to chemotherapy was the only adverse prognostic factor for both OS (63% +/- 12% versus 35% +/- 13%; P = .05) and PFS (55% +/- 16% versus 10% +/- 9%; P = .006). For patients with failure of a prior autologous hematopoietic stem cell transplantation, results were especially good for those who experienced late relapses (>/=12 months: 2-year OS and PFS were 75% +/- 16% and 70% +/- 18%, respectively). These data suggest that allo-RIC is feasible in heavily pretreated HL patients and has an acceptable early transplant-related mortality. Results are better in patients allografted in sensitive disease. Both responses observed after the development of GVHD and DLI may suggest a graft-versus-HL effect. Allo-RIC has to be considered an effective therapeutic approach for patients who have had treatment failure with a previous autologous hematopoietic stem cell transplantation.  相似文献   
6.
BackgroundObesity has been described as a protective factor in cardiovascular and other diseases being expressed as ‘obesity paradox’. However, the impact of obesity on clinical outcomes including mortality in COVID-19 has been poorly systematically investigated until now. We aimed to compare clinical outcomes among COVID-19 patients divided into three groups according to the body mass index (BMI).MethodsWe retrospectively collected data up to May 31st, 2020. 3635 patients were divided into three groups of BMI (<25 kg/m2; n = 1110, 25?30 kg/m2; n = 1464, and >30 kg/m2; n = 1061). Demographic, in-hospital complications, and predictors for mortality, respiratory insufficiency, and sepsis were analyzed.ResultsThe rate of respiratory insufficiency was more recorded in BMI 25?30 kg/m2 as compared to BMI < 25 kg/m2 (22.8% vs. 41.8%; p < 0.001), and in BMI > 30 kg/m2 than BMI < 25 kg/m2, respectively (22.8% vs. 35.4%; p < 0.001). Sepsis was more observed in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (25.1% vs. 42.5%; p = 0.02) and (25.1% vs. 32.5%; p = 0.006). The mortality rate was higher in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (27.2% vs. 39.2%; p = 0.31) (27.2% vs. 33.5%; p = 0.004). In the Cox multivariate analysis for mortality, BMI < 25 kg/m2 and BMI > 30 kg/m2 did not impact the mortality rate (HR 1.15, 95% CI: 0.889?1.508; p = 0.27) (HR 1.15, 95% CI: 0.893?1.479; p = 0.27). In multivariate logistic regression analyses for respiratory insufficiency and sepsis, BMI < 25 kg/m2 is determined as an independent predictor for reduction of respiratory insufficiency (OR 0.73, 95% CI: 0.538?1.004; p = 0.05).ConclusionsHOPE COVID-19-Registry revealed no evidence of obesity paradox in patients with COVID-19. However, Obesity was associated with a higher rate of respiratory insufficiency and sepsis but was not determined as an independent predictor for a high mortality.  相似文献   
7.
G Pados  J Iványi  I F?ldes  M Dudás  C Farsang 《Orvosi hetilap》1990,131(21):1139-1141
Prazosin (Minipress) monotherapy was given to 152 patients with essential hypertension for one year in a multi-center study involving 13 hospitals and university clinics. In three centers serum levels of total cholesterol, HDL-cholesterol and triglycerides were also determined in 32 patients with hypertension and hyper/dys-lipoproteinemia. As a consequence of Minipress monotherapy significant decreases were found in serum level of cholesterol (after three months and also after one year), triglycerides (after one year), while the serum concentration of HDL-cholesterol increased. Atherogenic index (a ratio of total cholesterol over HDL-cholesterol) was significantly decreased by Minipress. As new data showing a causative correlation between hypertension and hyperlipoproteinemia were published in the literature authors, on the basis of their results, suggest to determine lipid profile in every patient with hypertension. They regard Minipress as the first line drug in young patients with "familial dyslipidemic hypertension". When choosing an antihypertensive drug metabolic side effects should be taken into consideration.  相似文献   
8.
Plasma retinol and -carotene levels were measured in 502 preschool Guatemalan children from five rural hamlets. Their ages ranged from 6 to 78 months (mean: 42.9±19.2 months); 45% males and 55% females. The mean retinol value in the whole group was 0.9±0.4 µmol/1 (range: 0.1 to 8.4 µmol/1). There was no significant difference between sexes in retinol mean values nor in the incidence of retinol values less than 0.7 µmol/1 (22% in males, 18% in females). When grouped by age and community, significant low retinol mean values were found in two hamlets in the youngest age group (12 to 23 months) as compared to the other age-groups (p<0.05). In the other two hamlets, there were no significant differences among retinol means by age-group. The highest prevalence of deficient retinol values by age-group was in the 12 to 23 months group (40%), and decreased as age increased. The mean value for -carotene in the whole group was 0.13±0.18 µmol/1 (range: 0.01 to 2.23 µmol/1). There were no significant differences in -carotene means between sexes in the whole group. Stratifying the -carotene data by age-groups and community, values were significantly higher in the 48–59 months and 72–83 months groups, as compared with the other age groups in two of the communities (p<0.05). Significant differences across communities for -carotene were found only in the 12 to 23 months group.  相似文献   
9.
Data relating to stroke patients at a department of internal medicine (50 beds) in a county teaching hospital were studied in period 1990-1994. In this five-year period, 1184 patients were admitted because of some forms of stroke. The mortality due to the stroke was 16.8% (199 patients, deceased group). Autopsy was performed on 159 of these 199 patients (autopsy rate: 79.8%). Age- and sex-matched controls were selected from the survivors (n = 159). The main risk factors of stroke were analyzed in both groups: hypertension, cardiac events (decompensation, atrial fibrillation, and old myocardial infarction), previously verified diabetes, and recurrent stroke in the history. The mean hospital nursing time for the survivors was 12.3 +/- 6.3 days, while that in the deceased 7.2 +/- 7.6 days. RESULTS: 1. Hypertension was present to similar extents in both groups (survivors: 82.1%, deceased group: 77.8%) 2. Decompensation occurred in 5% vs 18.2% fibrillation in 11.3% vs 13.8%, and old myocardial infarction in 5.6% vs 18.2% 3. Diabetes was observed in 21.3% vs 36.4% and 4. Recurrent stroke in 22.6% vs 39.6%. These risk factors strongly predicted the outcome of the stroke. Other recently observed factors (haemorrhagic form, conscious state, time of hospital admission, seasonal variation, higher erythrocyte sedimentation rate, hyperglycaemia, proteinuria, early deep vein trombosis) revealed also significant differences between survivors and deceased patients. Since pulmonary thromboembolism was twice as frequent in the deceased patients as in the survivors, early heparin prevention is necessary immediately after computer tomography which excluded the haemorrhagic type of cerebrovascular diseases.  相似文献   
10.
Poly(lactic-co-glycolic acid) (PLGA) microparticles are used in various disorders for the controlled or sustained release of drugs, with the management of salivary gland pathologies possible using this technology. There is no record of the response to such microparticles in the glandular parenchyma. The purpose of this study was to assess the morphological changes in the parotid gland when injected with a single dose of PLGA microparticles. We used 12 adult female Sprague Dawley rats (Rattus norvegicus) that were injected into their right parotid gland with sterile vehicle solution (G1, n=4), 0.5 mg PLGA microparticles (G2, n=4), and 0.75 mg PLGA microparticles (G3, n=4); the microparticles were dissolved in a sterile vehicle solution. The intercalar and striated ducts lumen, the thickness of the acini and the histology aspect in terms of the parenchyma organization, cell morphology of acini and duct system, the presence of polymeric residues, and inflammatory response were determined at 14 days post-injection. The administration of the compound in a single dose modified some of the morphometric parameters of parenchyma (intercalar duct lumen and thickness of the glandular acini) but did not induce tissue inflammatory response, despite the visible presence of polymer waste. This suggests that PLGA microparticles are biocompatible with the parotid tissue, making it possible to use intraglandular controlled drug administration.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号