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   373篇
  免费   23篇
  国内免费   5篇
耳鼻咽喉   3篇
儿科学   11篇
妇产科学   1篇
基础医学   28篇
口腔科学   6篇
临床医学   21篇
内科学   103篇
皮肤病学   12篇
神经病学   12篇
特种医学   31篇
外科学   90篇
综合类   15篇
预防医学   10篇
眼科学   4篇
药学   15篇
肿瘤学   39篇
  2021年   4篇
  2020年   7篇
  2018年   8篇
  2017年   12篇
  2016年   15篇
  2015年   9篇
  2014年   11篇
  2013年   9篇
  2012年   14篇
  2011年   16篇
  2010年   21篇
  2009年   15篇
  2008年   17篇
  2007年   30篇
  2006年   10篇
  2005年   16篇
  2004年   10篇
  2003年   7篇
  2002年   6篇
  2001年   7篇
  2000年   10篇
  1999年   7篇
  1998年   7篇
  1997年   7篇
  1996年   7篇
  1994年   4篇
  1993年   4篇
  1992年   4篇
  1989年   9篇
  1988年   6篇
  1987年   5篇
  1986年   3篇
  1985年   3篇
  1983年   5篇
  1982年   5篇
  1980年   2篇
  1979年   5篇
  1978年   4篇
  1977年   3篇
  1976年   8篇
  1975年   3篇
  1974年   2篇
  1973年   2篇
  1972年   2篇
  1971年   3篇
  1970年   3篇
  1969年   2篇
  1968年   2篇
  1966年   3篇
  1936年   3篇
排序方式: 共有401条查询结果,搜索用时 14 毫秒
11.
Remarkable changes are seen on gross and microscopic examination of placenta of patients with sickle cell disorders, hence the present study was undertaken to find out the pathological changes seen in the placenta of sickle cell disorder patients, as compared to control and to study the effect of maternal sickling on the fetus. It includes total 73 cases, of which 10 were of control group and 63 were from patients with sickle cell disorders, which included 47 sickle cell trait (AS) and 16 sickle cell disease (SS) patients. In group II, 9 (14.28%) patients with SS pattern developed complications during pregnancy, in the form of vaso-occlusive and hemolytic crises. Pregnancy induced hypertension was seen in 4 (25%) out of 16 SS and 11 (23.40%) of the 47 AS patients. Urinary tract infection (UTI) was seen in 6 (37.5%) out of 16 SS and 8 (17.02%) out of 47 AS patients. Placentae in sickle cell disorders showed pathological changes in the form of infarction, calcification, sickled red blood cells and hemorrhage in intervillous spaces, increased syncytial knots, fibrinoid necrosis, stromal fibrosis, hyalinised villi and compensatory proliferation of trophoblastic cells.  相似文献   
12.
13.
The binding of [3H]BAY K 8644 [methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)- pyridine-5-carboxylate] to high and low affinity sites in rabbit ventricular membranes was characterized. Binding affinities were 0.66 and 138 nM at 15 degrees C and 9.1 and 72 nM at 37 degrees C, for the high and low affinity sites, respectively, and binding site densities were 0.3 and 14 pmol/mg at 15 degrees C and 0.41 and 1.4 pmol/mg at 37 degrees C, for the respective sites. The modification of high affinity [3H]BAY K 8644 binding by verapamil, diltiazem, tiapamil, Ca++ and EDTA appeared to be the same as that for nitrendipine binding, consistent with the hypothesis that the high affinity binding site for [3H]BAY K 8644 on isolated membranes is the same as the 1,4-dihydropyridine antagonist binding site. The binding of [3H]BAY K 8644 to a low affinity binding site was modified by temperature, Ca++ and diltiazem, but the lack of stereoselectivity, lack of denaturation by heat and the large number of sites indicated that most of the low affinity binding sites were not associated with Ca++ channels. It is concluded that the high affinity binding site for BAY K 8644 is associated with Ca++ channels, and is modified by at least some of the factors that modify the binding site for Ca++ channel antagonists, whereas many or all of the low affinity binding sites detected are not related to Ca++ channels.  相似文献   
14.
Lateral pancreatojejunostomy is a well-documented procedure for pain relief in chronic pancreatitis with a dilated main pancreatic duct. However, a number of patients develop recurrence of pain at variable intervals after a successful drainage procedure. A 40-year-old patient with tropical chronic pancreatitis developed recurrence of pain 13 years after a lateral pancreatojejunostomy. Investigation demonstrated a dilated main pancreatic duct. Re-exploration revealed a near complete closure of the previous lateral pancreatojejunostomy. A novel method of pancreatojejunal reconstruction was performed. Patient is pain-free after a follow-up of 18 months since surgery. The long-term status of lateral pancreatojejunostomy remains unclear. Our case documents, probably for the first time in published literature, a near total spontaneous closure of a previous lateral pancreatojejunostomy that was responsible for recurrence of pain. Our method of pancreatojejunal reconstruction adds to the armamentarium of the pancreatic surgeon.  相似文献   
15.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
16.

Background

Better appreciation of the course and factors that influence incidental gallbladder cancer is needed to develop treatment strategies aimed at improved outcomes. The purpose of this study was to determine pattern of disease recurrence and influencing factors in patients undergoing radical re-resection for incidental gallbladder cancer.

Methods

Patients undergoing radical re-resection from February 2003 to May 2010 were analyzed. Influence of variables (lymph node ratio, ASA grade, gender, adjuvant treatment, time interval between cholecystectomy and radical re-resection (in months), and TNM stage) on disease-free survival was assessed.

Results

Of 163 patients, 127 (92 female and 35 male patients; median age 50 years) underwent successful radical re-resection. Median duration between two surgeries was 2 months (range 1–10). Twenty-five percent of patients with pT1b disease had lymph node metastases. Two-year disease-free survival rate was 79.6 % (median follow-up, 16 months). On follow-up, 18 of 24 patients developed recurrences at distant sites. Lymph node metastasis was the single variable significantly influencing disease-free survival. Adjusting for disease stage when analyzing time interval between cholecystectomy and radical re-resection on a continuous scale as a prognostic factor for recurrence revealed no significant impact of increasing interval between surgeries (hazard ratio 1.12; 95 % confidence interval 0.95–1.34; p = 0.17).

Conclusions

The most important predictor of disease recurrence is lymph node metastases. In patients who undergo curative radical re-resection for incidental gallbladder cancer, recurrent disease is more likely to occur at distant sites. Patients with pT1b disease should be offered radical re-resection with a radical lymphadenectomy. It is not the delay in revision surgery but TNM stage that influences outcomes in incidental gallbladder cancer.  相似文献   
17.
This paper presents the histological appearance of the lymph nodes in cases of osteogenic sarcoma of the limb bones. The nodes were studied for the degree of sinus histiocytosis. Cases with no sinus histiocytosis showed a poor prognosis while cases with moderate to marked sinus histiocytosis showed a better rate of survival. Since the regional lymph nodes play an important part in the immunological process, preservation of regional nodes is suggested.  相似文献   
18.
19.
BACKGROUND: There is increasing evidence that immune mechanisms may be crucial in the development of alcoholic chronic pancreatitis. However, it is not known whether differences in underlying aetiology influence the inflammatory reaction in patients with chronic pancreatitis. The histological features and the pattern of inflammatory cell infiltration were studied in three aetiological forms of chronic pancreatitis: alcoholic, idiopathic and tropical pancreatitis. METHODS: Forty-three patients, ten with alcoholic, 12 with idiopathic and 21 with tropical chronic pancreatitis, were evaluated for the pattern of pancreatic inflammatory cell infiltration and histological features. Ten organ donors served as controls. Haematoxylin and eosin-stained tissue sections were used for histological evaluation. For immunohistochemical characterization of the inflammatory reaction, four antibodies-CD4, CD8, CD45 and CD68-were used. Quantitative evaluation of the various cell infiltrates was performed with computer-assisted image analysis. The inflammatory cell infiltration pattern was also evaluated. RESULTS: The degree of endophlebitis and the overall density of plasma cells were greater in tropical than in alcoholic chronic pancreatitis. The grade of intralobular fibrosis was significantly higher in tropical chronic pancreatitis compared with the idiopathic form. No significant quantitative differences in the specific cellular infiltrates (CD4, CD8, CD45, CD68) were observed in the three different groups. However, the perivascular inflammation number score was significantly higher in alcoholic compared with idiopathic pancreatitis (P = 0.037), and the perivascular inflammation area score was significantly lower in idiopathic than in alcoholic (P = 0.024) or tropical (P = 0.020) pancreatitis. CONCLUSION: Different aetiological forms of chronic pancreatitis result in similar histological features and a comparable inflammatory cell reaction, indicating that the disease, independent of the underlying aetiology, reaches a common immunological stage beyond which it appears to progress as a single distinctive entity.  相似文献   
20.
While the presence of eosinophils in the skin lesions of bullous pemphigoid is well documented, the chemotactic factors responsible for eosinophil recruitment into the tissue still remain to be defined. In this study, eotaxin and interleukin-5 (IL-5) concentrations were determined in the blister fluid and sera of patients with bullous pemphigoid (acute and remission phase, n=6) in comparison with normal healthy controls (n=6) using the enzyme-linked immunosorbent assay (ELISA) technique. Eotaxin and IL-5 levels were increased in the blister fluid compared with the acute and remission phase sera, as well as compared with the sera of normal controls. In addition, immunoreactivity for eotaxin was predominantly found in the inflammatory cell infiltrate of lesional bullous pemphigoid biopsy specimens. In conclusion, the data provide evidence that co-operation of eotaxin and IL-5 may play an essential role in activating and recruiting eosinophils, which ultimately contribute to the tissue damage in bullous pemphigoid.  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