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   15057篇
  免费   795篇
  国内免费   99篇
耳鼻咽喉   185篇
儿科学   359篇
妇产科学   413篇
基础医学   2045篇
口腔科学   322篇
临床医学   1410篇
内科学   3112篇
皮肤病学   539篇
神经病学   919篇
特种医学   677篇
外科学   2335篇
综合类   170篇
现状与发展   1篇
一般理论   2篇
预防医学   788篇
眼科学   310篇
药学   1154篇
中国医学   154篇
肿瘤学   1056篇
  2023年   93篇
  2022年   291篇
  2021年   490篇
  2020年   234篇
  2019年   297篇
  2018年   447篇
  2017年   323篇
  2016年   374篇
  2015年   470篇
  2014年   680篇
  2013年   711篇
  2012年   1145篇
  2011年   1121篇
  2010年   655篇
  2009年   533篇
  2008年   886篇
  2007年   903篇
  2006年   859篇
  2005年   816篇
  2004年   735篇
  2003年   581篇
  2002年   570篇
  2001年   428篇
  2000年   395篇
  1999年   311篇
  1998年   128篇
  1997年   93篇
  1996年   98篇
  1995年   70篇
  1994年   63篇
  1993年   34篇
  1992年   126篇
  1991年   108篇
  1990年   101篇
  1989年   67篇
  1988年   60篇
  1987年   68篇
  1986年   54篇
  1985年   54篇
  1984年   33篇
  1983年   24篇
  1980年   26篇
  1979年   31篇
  1977年   32篇
  1976年   25篇
  1975年   25篇
  1974年   29篇
  1973年   26篇
  1972年   30篇
  1970年   23篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A 32-year-old woman sustained a minor sliding accident with moderate to severe pain about the left distal thigh and hip and the right shoulder. Radiographs showed marked osteopenia, multiple osteolytic bone lesions, and a pathologic fracture of the left distal femur. Surgical intervention was conducted for the pathologic fracture, and the pathological findings confirmed the diagnosis of primary hyperparathyroidism with osteitis fibrosa cystica. We report this rare case here because it may be mistaken for neoplastic metastatic disease on radiographs and bone scan. The pathologic fracture usually heals and the bone mineral density improves significantly within 6 months after parathyroidectomy.  相似文献   
992.
Physiological characteristics of child athletes cannot be examined independently from the changes that occur during growth and maturation. This article reviews changes occurring in aerobic and anaerobic capacities, muscle strength and endurance in parallel with growth and development, and the factors affecting these changes, in particular, training. In addition, a brief evaluation is presented concerning the effects of physical activity, participation in sports, and training on growth and maturation.  相似文献   
993.
A significant transient increase in laser Doppler flowmetry (LDF) signals is observed in response to a local and progressive cutaneous pressure application in healthy subjects. This reflex may be impaired in diabetic patients. The work presents a signal processing providing the clarification of this phenomenon. Scalogram analyses of LDF signals recorded at rest and during a local and progressive cutaneous pressure application are performed on healthy and type 1 diabetic subjects. Three frequency bands, corresponding to myogenic, neurogenic and endothelial related metabolic activities, are studied. The results show that, at rest, the scalogram energy of each frequency band is significantly lower for diabetic patients than for healthy subjects, but the scalogram relative energies do not show any statistical difference between the two groups. Moreover, the neurogenic and endothelial related metabolic activities are significantly higher during the progressive pressure than at rest, in healthy and diabetic subjects. However, the relative contribution of the endothelial related metabolic activity is significantly higher during the progressive pressure than at rest, in the interval 200-400 s following the beginning of the pressure application, but only for healthy subjects. These results may improve knowledge on cutaneous microvascular responses to injuries or local pressures initiating diabetic complications.  相似文献   
994.
8 cases of tuberculosis were presented in this paper. Two patients had changes in the larynx and pharynx and one patient had pharyngeal tuberculosis and squamous carcinoma of epiglottis. Further specialty investigations e.g. MDL, biopsy, histopathological and bacteriological examinations were done and revealed proper diagnosis tuberculosis. Etiology, pathogenesis, diagnostic were described. Changes of tuberculosis were in unusual location. All patients were treated tuberculostatic drugs.  相似文献   
995.
Chronic otitis media (COM) is an inflammatory process involving the middle ear mucosa and the tympanic membrane. The healing and epidermization is mostly impaired by immunological response of the host. Investigating the activity and the function of immunological response elements one can learn the immunological mechanisms taking place in chronic otitis media. The ultrastructural investigations of the tympanic membrane were done on its fragments obtained from 19 patients with COM during middle ear surgery, performed at ENT Department of Medical University of Gdańsk in the years 1997-1999. Immunohistochemical investigations were performed using monoclonal antibodies against tenascin, S-100 protein, Ki 67, CD 31, F VIII, HLA-DR, TGFbeta1 and EGFR. The control group was 11 healthy tympanic membranes from cadavers. The presence of tenascin was proven in all COM tympanic membranes and in 45.5% of those from control group. S-100 protein was present in 88.9% of the patients with COM and absent in control group. Ki 67 was observed in 44.4% of the patients with COM and in 27.3% of the healthy tympanic membranes. Angiogenesis factors (CD 31 and FVIII) were present in 77.8% of the investigated COM tympanic membranes, in control group in 45.5%. HLA-DR expression was observed in 90% COM patients, in control group in 72.7%. Growth factor TGFbeta1 was present in the all cases in mucous and fibrous layer and in 54.5% of healthy tympanic membranes. EGF receptor was present in 60% of COM patients, mainly in epithelial layer of tympanic membrane and in 54.5% of those from control group. The presented investigations confirm the immunological activity of tympanic membrane in chronic otitis media.  相似文献   
996.
The aim of this study was to quantitate total T lymphocytes (total CD3+ cells) and T-lymphocyte subtypes (CD4+ [T helper] and CD8+ [T suppressor] cells) in patients with chronic sinusitis who were treated with functional endoscopic sinus surgery (FESS) and to investigate the pathophysiology of persistent inflammation in chronic sinusitis. This prospective study was conducted in study and control groups. The study group consisted of 32 patients (20 male, 12 female) with chronic sinusitis who underwent FESS. The control group consisted of 8 nonsinusitis patients (5 male, 3 female) who underwent septoplasty. Specimens from the study group were excised from five regions: the uncinate process, maxillary and ethmoid sinuses, and middle and inferior turbinates. The specimens were examined with x10 magnification by light microscopy, and the slides with a severe inflammatory process were included. Punch biopsy of the control group was taken from the inferior turbinate with patients' written approval. The surgical specimens from the study and control groups were examined with an immunohistochemical staining technique with monoclonal antibodies against CD3, CD4, and CD8 surface antigens of T lymphocytes. In every specimen, the numbers of CD3+, CD4+, and CD8+ cells were calculated in 3 to 4 high magnification field on light microscopy, and the mean number of these cells in the epithelium, subepithelial layer of the lamina propria, and deep paraglandular layer of the mucosa was determined. Statistical analysis by Kruskal-Wallis analysis of variance and the Mann-Whitney U test with Bonferroni correction revealed that the CD3 epithelial layer value of the inferior turbinate (p = .030) and the CD4 deep layer value of the middle turbinate (p = .048) were significantly higher than the corresponding values of the control group. In the epithelial (p = .018) and subepithelial (p = .012) layers of the uncinate process group, in the epithelial (p = .050) and subepithelial (p = .012) layers of the ethmoid sinus group, and in the subepithelial (p = .018) and deep paraglandular (p = .012) layers of the middle turbinate group, the difference between the CD4+ and CD8+ cell counts was found to be statistically significant by the Wilcoxon signed rank test. The number of CD4+ cells was higher than the number of CD8+ cells. In conclusion, T cells play a role in the pathophysiology of chronic sinusitis. CD4+ T helper cells, in particular, are predominant at the initiation and regulation of inflammation. The uncinate process, ethmoid sinus, and middle and inferior turbinates have the main roles by T cells and subtypes in the defense system in chronic sinusitis.  相似文献   
997.
A 52-year-old female patient is described who was aperated upon for a giant osteoma involving the right side ethmoid labyrinth bulging into the orbit shifting the eyeball, passing into right of the frontal and sphenoidal sinuses. We obtained complete cure and good cosmetic result.  相似文献   
998.
Patients with familial Mediterranean fever routinely take daily multiple doses of colchicine to prevent acute attacks and to reduce the risk of amyloidosis. However, although there is no research in this regard in the literature, some clinicians believe that the use of colchicine in children as daily single dose may cause toxic side effects. The efficiency and the side effects of the administration of daily single dose versus daily multiple doses of colchicine were evaluated in the treatment of patients with familial Mediterranean fever. Thirty-nine patients being observed at Atatürk University Medical Faculty Pediatrics outpatient clinic with the diagnosis of familial Mediterranean fever were randomly divided into 2 groups. Group I consisted of 20 patients who continued taking colchicine in 2 or 3 divided doses daily as they did before the study. Group II comprised 19 patients who were given the total daily colchicine dose at 1 time. Patients were re-examined at 30-day intervals and both groups maintained this regimen for an average duration of 8 months. There was no difference between these 2 groups with respect to frequency of side effects, number of attacks, and acute phase response. Therefore, the daily colchicine dose can be given to children once daily.  相似文献   
999.
1000.
Choi D  Kim SK  Choi SH  Ko YG  Ahn CW  Jang Y  Lim SK  Lee HC  Cha BS 《Diabetes care》2004,27(11):2654-2660
OBJECTIVE: Despite the popularity of coronary stenting in coronary artery disease (CAD), restenosis remains a challenging clinical problem. This study evaluated the efficacy of rosiglitazone for preventing in-stent restenosis in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: We conducted a prospective, randomized, case-controlled trial involving 95 diabetic patients with CAD who were randomly assigned to either the control or rosiglitazone group (48 and 47 patients, respectively). Quantitative coronary angiography (QCA) was performed at study entry and again at 6-month follow-up. The primary end point was the restenosis rate, which was determined by QCA. RESULTS: Eighty-three patients (45 patients with 55 lesions in the control group and 38 patients with 51 lesions in the rosiglitazone group) completed follow-up angiography. Rosiglitazone treatment for 6 months reduced fasting insulin concentration. The high-sensitivity C-reactive protein concentration was significantly reduced in the rosiglitazone group compared with that in the control group (from 2.92 +/- 1.98 to 0.62 +/- 0.44 mg/l, P < 0.001 vs. from 2.01 +/- 1.33 to 1.79 +/- 1.22 mg/l, P = NS). However, the baseline and follow-up glucose and lipid concentrations were not different between two groups. The rate of in-stent restenosis was significantly reduced in the rosiglitazone group compared with the control group (for stent lesions: 17.6 vs. 38.2%, P = 0.030). The rosiglitazone group had a significantly lower degree of diameter stenosis (23.0 +/- 23.4% vs. 40.9 +/- 31.9%, P = 0.004) compared with the control group. CONCLUSIONS: We demonstrated that treatment with rosiglitazone significantly reduces in-stent restenosis in diabetic patients with CAD who underwent coronary stent implantation.  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