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   143篇
  免费   6篇
耳鼻咽喉   19篇
妇产科学   17篇
基础医学   18篇
口腔科学   3篇
临床医学   5篇
内科学   27篇
皮肤病学   3篇
神经病学   2篇
特种医学   1篇
外科学   39篇
综合类   3篇
预防医学   4篇
药学   4篇
肿瘤学   4篇
  2023年   3篇
  2022年   1篇
  2021年   3篇
  2020年   3篇
  2019年   2篇
  2018年   3篇
  2017年   3篇
  2016年   1篇
  2014年   4篇
  2013年   7篇
  2012年   4篇
  2011年   8篇
  2010年   10篇
  2009年   5篇
  2008年   14篇
  2007年   10篇
  2006年   11篇
  2005年   9篇
  2004年   22篇
  2003年   10篇
  2002年   5篇
  2001年   6篇
  2000年   2篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
排序方式: 共有149条查询结果,搜索用时 609 毫秒
41.
A laryngocele is an abnormal dilatation of the laryngeal saccule. The relationship between layngoceles and laryngeal carcinoma is still debated. We present the case of a 45-year-old male patient with bilateral asymptomatic laryngocele and laryngeal squamous cell carcinoma. We discuss the possible etiopathogenetic influence of increased intralaryngeal pressure with preoperative CT and explorative findings, and the current literature is reviewed.  相似文献   
42.
Expression of inducible nitric oxide synthase in antrochoanal polyps   总被引:3,自引:0,他引:3  
OBJECTIVE: Antrochoanal polyp (ACP) is a polypoid lesion originating from the maxillary sinus, emerging from the ostium and extending to the choana. Although the etiologic causes of ACP are not known completely, it presents a fairly uniform clinical appearance. Nitric oxide (NO) has an important role in non-specific immunoreactions and inflammation in various tissues and has a main regulatory role in airway function and seems to involve in pathomechanism of several respiratory system diseases. NO is synthesized by the effect of three isoforms of nitric oxide synthase i.e. inducible NOS (iNOS). Some studies revealed that ACP has some different characteristics from the ordinary nasal polyps. In the present study, in order to compare ACP with allergic and non-allergic nasal polyps (NANP), we detected and localized the iNOS expression and also evaluate some histological parameters. METHODS: Twenty-six cases were chosen from the files and four controls were used. The cases were separated as follows: normal inferior turbinate mucosa as control (n=4) ACPs (n=8), allergic nasal polyps (ANP) (n=9), and NANP (n=9). Five-micrometer thick sections were prepared from the paraffin sections of polyps and normal nasal mucosa to quantify the iNOS expression. iNOS protein was observed in the cytoplasm of epithelial and stromal inflammatory cells. iNOS protein expression in the groups was assessed according to the intensity of staining and histomorphological parameters, oedema, lymphocytic and eosinophilic cell infiltration were detected semi quantitatively. RESULTS: iNOS expressions, either stromal or epithelial, were not different from each other among the four groups. Although it is not statistically significant, we noted that ANP and ACP frequently showed moderate and severe iNOS protein expression in epithelial and stromal parts when compared with NANPs and controls. Also, iNOS expression was significantly higher in the stroma of the ANPs than NANPs (P=0.012). CONCLUSIONS: ACPs and ANPs have frequently showed moderate and significant epithelial and stromal iNOS expression. Further studies are needed in large groups to elucidate differences between ACP and the other nasal polyps.  相似文献   
43.
BACKGROUND: The aim of this study was to investigate systolic pulmonary artery pressure (SPAP) and serum uric acid (SUA) levels in patients with hyperthyroidism and after euthyroid state was reached. METHODS: Twenty five (10 male, 15 female, mean age 49.8 +/- 11.6 years) consecutive patients with hyperthyroidism (18 due to toxic nodular goiter, seven to Graves' disease) and 25 (eight male, 17 female, mean age 48.7 +/- 8.7 years) healthy controls were included in the study. Thyroid hormones, SUA, glucose, urea, creatinine, and transthoracic echocardiography were performed in all patients. All tests were repeated after treatment of hyperthyroidism. RESULTS: Mean SPAP and SUA levels in patients with hyperthyroidism were significantly higher than in controls (30.4 +/- 8.5 vs. 22 +/- 3.7 mmHg, p <0.0001, and 5.1 +/- 1.1 vs. 4.3 +/- 0.5 mg/dL, p = 0.004, respectively). Elevated SPAP and SUA levels in patients with hyperthyroidism decreased significantly after treatment to levels comparable with controls (24.4 +/- 5.4 mmHg, p = 0.001 and 4.6 +/- 0.9 mg/dL, p = 0.002, respectively). Correlation between SPAP and SUA levels, however, was not significant in hyperthyroid population and after euthyroid stage was reached (r = 0.34, p = 0.097, and r = 0.256, p = 0.216, respectively), possibly due to relatively low number of patients (overall correlation of SPAPs and SUAs was r = 0.4, p <0.0001). CONCLUSIONS: Hyperthyroidism should be included in differential diagnosis of pulmonary arterial hypertension. However, further investigations are needed to determine the exact mechanism between hyperthyroidism and pulmonary hypertension.  相似文献   
44.
OBJECTIVE: To investigate the serum leptin levels in patients with allergic rhinitis during the symptomatic period. STUDY DESIGN AND SETTING: A randomized, prospective study was performed on 26 adult patients with allergic rhinitis and 20 control subjects with similar age, sex and body mass index in a tertiary otolaryngology center. RESULTS: Leptin levels were 28.8 +/- 14.1 ng/mL in the patients with allergic rhinitis, and 20.8 +/- 13.5 ng/mL in the control group respectively. The difference between the groups was statistically significant (p = 0.04). CONCLUSION: Serum leptin levels were found to be significantly higher in patients with allergic rhinitis in symptomatic period. SIGNIFICANCE: Apart from its primary role in the regulation of body weight and energy expenditure, leptin may have a role in the inflammatory process of the allergic rhinitis.  相似文献   
45.
Intussusception is a rare occurrence in the adult population with most of the cases seen during the childhood period. Compared with the pediatric intussusceptions, there is more often an underlying cause in adults. Lipoma as a lead point for colonic intussusception is rare. Ultrasound may be helpful in the diagnosis, but computed tomography is more reliably used for differential diagnosis. An adult patient with colo-colonic intussusception diganosed with ultrasound and confirmed with computed tomography is presented.  相似文献   
46.
Central giant cell reparative granuloma (CGCRG) is an uncommon benign, reactive osseous lesion usually located in the mandible and maxilla. Although it is histologically benign, it may be locally destructive. There is still controversy on its development and growth pattern. Surgery is the treatment traditionally recommended. In this article, we presented a 12 year-old girl CGCRG of the mandible caused by a molar tooth extraction and discussed its histopathological, clinical, radiological and therapeutic features in the light of the current literature. Also we described our additional surgical maneuver 'drilling the surgical field' after the removal of the lesion.  相似文献   
47.
Adult articular cartilage is a hypoxic tissue, with oxygen tension ranging from <10% at the cartilage surface to <1% in the deepest layers. In addition to spatial gradients, cartilage development is also associated with temporal changes in oxygen tension. However, a vast majority of cartilage tissue engineering protocols involves cultivation of chondrocytes or their progenitors under ambient oxygen concentration (21% O2), that is, significantly above physiological levels in either developing or adult cartilage. Our study was designed to test the hypothesis that transient hypoxia followed by normoxic conditions results in improved quality of engineered cartilaginous ECM. To this end, we systematically compared the effects of normoxia (21% O2 for 28 days), hypoxia (5% O2 for 28 days) and transient hypoxia—reoxygenation (5% O2 for 7 days and 21% O2 for 21 days) on the matrix composition and expression of the chondrogenic genes in cartilage constructs engineered in vitro. We demonstrated that reoxygenation had the most effect on the expression of cartilaginous genes including COL2A1, ACAN, and SOX9 and increased tissue concentrations of amounts of glycosaminoglycans and type II collagen. The equilibrium Young's moduli of tissues grown under transient hypoxia (510.01 ± 28.15 kPa) and under normoxic conditions (417.60 ± 68.46 kPa) were significantly higher than those measured under hypoxic conditions (279.61 ± 20.52 kPa). These data suggest that the cultivation protocols utilizing transient hypoxia with reoxygenation have high potential for efficient cartilage tissue engineering, but need further optimization in order to achieve higher mechanical functionality of engineered constructs. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 544–553, 2013  相似文献   
48.
Serotonin transporter gene polymorphism in irritable bowel syndrome   总被引:19,自引:0,他引:19  
OBJECTIVES: Serotonin is a key mediator of intestinal peristalsis, and after it is secreted, it is effectively cleansed from the neuronal gap by means of a high affinity substance called serotonin transporter (SERT), which depends on the Na+ and Cl- ions localized in the presynaptic neuronal membranes. The aim of this study was to investigate SERT polymorphism in patients with irritable bowel syndrome (IBS). METHODS: SERT gene polymorphism was assessed by polymerase chain reaction on DNA chains obtained from leukocytes in serum samples from 54 patients diagnosed with IBS and 91 healthy subjects. The polymorphism of two regions (variable number tandem repeats and the SERT gene-linked polymorphic region [5-HTTLPR]) of SERT was assessed. RESULTS: SERT polymorphisms were found to be similar in healthy subjects and IBS patients (p > 0.05). IBS patients were divided into three groups: diarrhea predominant (n = 18), constipation predominant (n = 26), and alternating diarrhea and constipation (n = 10). These groups were compared with respect to gene polymorphism, and it was found that the 5-HTTLPR allele S/S genotype occurred with greater frequency in the constipation predominant group than in the other two subgroups (p < 0.05), and L/S genotype frequency in the diarrhea predominant group was higher than those in the constipation and control groups. CONCLUSIONS: No relationship was found between IBS and SERT gene polymorphism. It is conceivable that the presence of the S/S genotype in IBS patients carries an increased risk of the constipation predominant type of IBS, whereas the presence of the 5-HTTLPR allele L/S genotype carries an increased risk of the diarrhea predominant type.  相似文献   
49.
50.
INTRODUCTIONSarcomatoid carcinoma (SCA) of the small bowel is an extremely rare tumor with only 21 cases reported in literature and GISTs are relatively rare gastrointestinal neoplasms.PRESENTATION OF CASEWe report a case of an 85 year-old female admitted with intestinal obstruction in June 2010. She suffered from polymyalgia rheumatica and was under surveillance for a presumed gastric GIST. A laparotomy was performed with resection of the jejunal obstruction and complete excision of the gastric mass. Histology confirmed a gastric GIST and sarcomatoid carcinoma of the small bowel. The patient was discharged 21 days after the operation and died on the 88th post-operative day.DISCUSSIONSynchronous GISTs and other malignancies have been reported over the last years with increasing frequency.Sarcomatoid carcinoma of the small bowel is an aggressive neoplasm with poor survival rates and surgery is the cornerstones of treatment. Given its unpredictable clinical behaviour and concomitant association with other malignancies, GISTs require adequate surgical resection with careful, long-term follow-up.CONCLUSIONThis is the first case of concomitant gastric GIST with Sarcomatoid carcinoma of the small bowel, and the first report of sarcomatoid small bowel carcinoma in association with polymyalgia rheumatica.  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