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61.
Merkel cell carcinoma is an uncommon and aggressive primary neuroendocrine skin malignancy which mostly affects the extremities and the head and neck region of elderly patients. Merkel cell carcinoma occurs with increased frequency in sun-exposed areas, in individuals exposed to arsenic and in immunosuppressed patients. Many patients with Merkel cell carcinoma present with other malignancies, mainly skin cancers. Characteristic features are frequent recurrences and regional and distant metastases. Mortality rates range from 20 to 65 per cent. The mainstay of treatment is surgery, with wide local excision, and adjuvant radiotherapy is usually administered. Merkel cell carcinoma of unknown primary site is rare, and the majority of the few cases described have not been from head and neck areas. We present a case of Merkel cell carcinoma of unknown primary site, with upper neck and distant metastases.  相似文献   
62.
三叶因子与胃黏膜保护的研究进展   总被引:1,自引:0,他引:1  
三叶因子家族是一群主要由胃肠道黏液细胞分泌的小分子多肽.其共同特征为均含一特殊的P结构域及三叶状结构.这种稳定的结构使三叶因子家族具有明显的抗蛋白酶水解、酸消化及耐热特性,因而能在消化道复杂的环境中保持生物活性.目前在哺乳动物体内发现的有pS2/TFF1、SP/TFF2和ITF/TFF3三种,它们具有黏膜保护与修复、肿瘤抑制、信号传导、调节细胞凋亡等功能.本文阐述了三叶因子家族发现的历史,并初步探讨了其作用.同时也对三叶因子受体这一热点的研究现状进行总结.  相似文献   
63.
HPLC分离测定格列齐特片及其有关物质   总被引:6,自引:0,他引:6  
目的:建立新的HPLC法分离测定格列齐特征及其有关物质。方法:色谱条件为:Shim-Pack VP-ODS(5um,150mm*4.6mm i.d.)色谱柱;甲醇-0.02mol/L磷酸(用三乙胺调节PH至3.5),(70:30)为流动相;检测波长为229nm。结果:在50-300ug;/ml的浓度范围内线性关系良好。r=0.9999(n=6);平均回收率为100.5%,RSD为0.17%(n=6),重复进样RSD为0.12%(n=6),格列齐特及其有关物质得到基线分离。结论:本法简便,快速,准确,适用于格列齐特及其制剂的质量控制。  相似文献   
64.
去甲乌药碱对实验性心力衰竭的治疗作用   总被引:11,自引:0,他引:11  
去甲乌药碱(DMC)是中药附子的有效成分之一。静脉滴注DMC2μg/kg/min共5min,使豚鼠正常心脏的收缩力明显加强,LVSP和LV dP/dtmax分别增加58±7和25±7%;心衰后,LVSP和LV dP/dtmax分别下降到心衰前的40±5和30.5±2.8%。DMC可使之恢复到79±14和75±9.9%,DMC也能加强离体豚鼠衰竭心脏的收缩力。DMC的强心作用与ISO相似,但前者作用较弱,作用维持时间较长,这可能与他们的作用机制不同有关。  相似文献   
65.
Antibacterial properties of human amniotic membranes.   总被引:21,自引:0,他引:21  
Amniotic membranes are widely used in a multitude of surgical applications and have been shown to reduce bacterial counts and promote healing in infected wounds. Antibacterial properties of amniotic fluid are well documented and the presence of many potentially antibacterial factors has been demonstrated. No such factors have yet been found in amniotic membranes. We have applied a direct disc-diffusion susceptibility test to try to establish the possible existence of such a factor. Amniotic membranes did not inhibit five bacterial species when tested at 3 X 10(6) and 3 X 10(8) colony forming units/ml. However, complete growth inhibition of all organisms was seen immediately under the amniotic membrane discs. These results support the hypothesis that the antimicrobial effect of amniotic membranes in vitro is due to their close adherence to the wound surface.  相似文献   
66.
Summary The element content of ossified auricles in two patients with Addison's disease was determined by X-ray microanalysis. The results showed a similar element content of the ossified auricles of the Addison's patients and control bone specimens. The calcium and phosphorus content of the petrified auricles was, however, slightly decreased compared with the iliac bone biopsies of the patients. The sulfur content of the ossified auricles was higher than that of their bones, but markedly lower than control auricular cartilage. Iron, sodium, and chloride contents were similar in the ossified auricles and in the normal auricular cartilage, whereas only trace amounts of these elements were detected in the bone. The auricles of the patients with Addison's disease possessed relatively high aluminium content compared with both control bone and cartilage. The element content of the bone biopsies from Addison patients was comparable to control bone. The presence of trace amounts of aluminium in the petrified auricles of Addison's patients is probably attributed to a long period of aluminium hydroxide consumption.  相似文献   
67.
68.
Objective: To examine the incidence of late presentation of patients with recurrent pleomorphic adenoma (RPA) of the parotid gland.

Methods: This is a retrospective analysis of patients treated in our center. We examined patients demographics, disease characteristics, treatment, and outcome and as well as the time period length from the first discovery of a recurrent mass until seeking treatment at our clinic and its effect on morbidity.

Results: A total of 30 patients were included. 26% underwent initial enucleation in other institutions. In eight patients (26%), the recurrence of the mass was second or higher. The patients average time period length until seeking treatment was 2.48 years, with 33% of patients showing a time period length of over three years. Multifocal tumor, tumor diameter larger than 2?cm and facial nerve involvement were found in 15 (50%),16 (53.3%) and seven (25%) patients respectively. Patient's delay of presentation by ≥3 years was associated with a tumor size of ≥2?cm (Relative Risk [RR]?=?2, p?=?.02). Patient's delay of presentation by ≥2 years was also associated with a trend towards a higher rate of post-operative facial nerve palsy (RR?=?3.37, p?=?.07, CI?=?0.88–12.85).

Conclusion: Most patients with RPA were presented late, thus affecting disease extent and surgical morbidity.  相似文献   
69.
王长春  李梁  堵玉萍 《医学争鸣》2000,21(10):I220-I220
0 引言 慢性阻塞性肺部疾病 (COPD)合并呼吸衰竭患者常需鼻或气管插管 (或切开 )进行机械通气治疗 .气管插管为创伤性 ,并发症多 ,病死率高 .本院用面罩式双正压机械通气治疗取得一定疗效 .1 材料和方法1.1 材料  1996 /1998年本院呼吸科住院患者 41(男 32 ,女9)例 ,平均年龄 71(6 2~ 88)岁 ,均为 COPD合并 型呼吸衰竭 ,依据广州全国慢性支气管炎临床专业会议鉴定标准诊断 .1.2 呼吸机 为美国伟康医疗产品集团公司生产的双正压机械呼吸机 (Bipap呼吸机 ) .1.3 方法 患者半卧位 ,吸气压从 6 cm H2 O,呼气压从2 cm H2 O开始 …  相似文献   
70.
Thyroid function may be reduced after treatment of cancer of the head and neck, and hypothyroidism is much more common after combination therapy. Whether hypoparathyroidism and subsequent hypocalcemia also occur after such treatment is unknown. Few related studies have been published in which changes in total serum calcium have been studied after cancer treatment with radioactive iodine or external radiation. Twenty-two disease-free head and neck cancer patients were studied, 1 to 3 years after multimodal treatment, to determine if changes in serum ionized calcium levels or thyroid function were present. Our results suggest that parathyroid function, as represented by ionized calcium levels remains normal after multimodality (surgery, radiation and/or chemotherapy) combined treatment.  相似文献   
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