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1.
对18只大鼠进行内皮素脊髓鞘内注射,观察及记录大鼠后肢功能状态,并将18只大鼠分为3个不同的时间处死,进行病理形态学观察。结果表明:3组均表现缺血缺氧病理改变。2及4h实验组病变重于30min实验组。脊髓下胸段、腰段病变重于颈段及骶尾段。同时发现,大鼠后肢的功能状态与其脊髓相应的病理形态学变化不呈正比。  相似文献   
2.
立体定向开放显微手术治疗脑内致痫小病灶   总被引:1,自引:1,他引:0  
目的脑内致癫痫小病灶术前、术中的精确定位和病灶切除,是手术治疗效果的关键。探讨立体定向开放微创手术,皮层电极监测下切除脑内致痫小病灶的手术方法。方法53例症状性癫痫病例,CT、MR I检查有脑内小病灶(直径在0.5~3.0 cm),24 h视频脑电图确认致痫灶为脑内单发病灶。ASA 601S型立体定向仪CT引导辅助全麻环钻开颅,导针穿刺放置导管引导,显微镜下手术分离、切除病灶,皮层脑电图确认将致痫灶切除。结果病灶全切率达96.2%,术后50例得到随访,随访时间5~12个月,平均6.3个月,癫痫消失45例,脑电图检查记录到癫痫波11例,临床癫痫发作5例。因肺癌死亡3例。结论CT立体定向引导,显微手术切除颅内致痫小病灶,术中皮层电极确认将致痫灶切除,是一种定位精确、微创、安全、有效的治疗方法。  相似文献   
3.
OBJECTIVES: In this study, cancer survival rates for patients diagnosed in Ontario and selected areas within the United States were compared. METHODS: Relative survival rates were computed for patients aged 15 through 84 years diagnosed with any of four forms of cancer (breast, colon, lung, and Hodgkin's disease). The cohorts represented those diagnosed over the years 1978 through 1986 in the Canadian province of Ontario and in nine regions covered by the US National Cancer Institute's Surveillance Epidemiology and End Results program. Patients were followed through the end of 1990. RESULTS: The cumulative relative survival rates were similar for American and Canadian patients. The largest difference was observed for breast cancer, where patients in the United States enjoyed a survival advantage throughout the follow-up period. CONCLUSIONS: Patients in the United States and Ontario with the diseases studied, except for breast cancer, experience very similar survival. The greater use of mammographic screening in the United States could account for that country's higher breast cancer survival rate by promoting earlier and therefore more efficacious treatment, by introducing bias, or by a combination of both treatment and bias factors.  相似文献   
4.
Delayed sternal closure following cardiac operations   总被引:2,自引:0,他引:2  
In 13 patients, sternal closure was delayed at the end of open heart procedures. Seven patients underwent coronary artery bypass surgery (CAB), 5 valve replacements, and one left ventricular aneurysmectomy and closure of post myocardial infarction VSD. In all, primary closure of the sternum was considered impossible or inadvisable. The major indications for delaying sternal closure were: cardiac dilatation with tamponade-like behaviour upon attempted sternal closure (8 patients); intractable bleeding (2); intractable arrhythmia (1); insertion of mediastinal assist devices (3) and intraoperative non-cardiogenic pulmonary edema (1). In all, only the skin was closed. Delayed sternal closure (DSC) was performed 36-120 hours later on 10 of the patients, when their condition had stabilized. Nine patients are long term survivors. None of these patients has developed mediastinitis, wound infection, osteomyelitis or instability of the sternum. The judicious use of DSC in selected situations has several advantages: hemodynamic deterioration from pressure upon the heart may be prevented; a quick access to the heart in case of tamponade or intractable arrhythmia is obtained; insertion of mediastinal assist devices is facilitated. With careful technique the risk of infection is low.  相似文献   
5.
将BNP和AT-Ⅱ、ACTH AVP单独或BNP与这3种肽分别合并在大鼠icv或iv注入后观察血Ald浓度的变化。实验结果表明:①iv给予AVP(5μg/3ml·h~(-1))、ACTH(5μg/3ml·h~(-1))和AT-Ⅱ(5 v.g/3 ml·h(-1)),1h后均能增加血Ald的浓度。iv给予BNP(5μg/3ml·h(-1))能明显抑制AVP和ACTH的刺激作用,而不影响AT-Ⅱ的刺激作用。②icv给予BNP(2 Vg/10 pl NS)能降低血Aid浓度。icv给予AVP(2μg/10μl NS)能增加血Aid浓度,但ACTH(2μg/10μl NS)和AT-Ⅱ(2μg/10μl NS)无此种作用。但如脑室同时给予BNP(2μg/10μlNS)却可明显刺激Aid分泌。③icv注入BNP对外周注入的3种多肽的刺激作用无任何影响。从上述的实验结果可看出:脑内BNP可“反常”地增加AT-Ⅱ、ACTH和AVP对Ald分泌的刺激作用,与外周抑制AVP,ACTH的刺激作用不同。而脑内BNP不影响这3种多肽的外周刺激作用。结论是脑内BNP以其独特的方式调节Ald的分泌,控制水盐代谢。  相似文献   
6.
A 7 1/2-year-old girl with an inflammatory pseudotumor of the lung is presented. The nature of the lesion was not recognized pre-or intraoperatively. The lesion was rubbery, yellowish, and well-defined but not encapsulated. Histologically, a spindle-cell lesion with a storiform pattern and chronic inflammatory-cell infiltrate was seen. The immunological and ultrastructural studies supported an inflammatory origin. The lesion corresponds to the fibrous histiocytoma variant of inflammatory pseudotumor of the lung, as defined recently by Matsubara et al. [17]. This must be distinguished from rare benign neoplasms of the lung such as benign fibrous histiocytoma, leiomyoma, Schwannoma, and histiocytosis.  相似文献   
7.
Calcineurin (CaN) is a Ca2+- and calmodulin-dependent protein phosphatase (PP2B) that, in yeast, is an integral intermediate of a salt-stress signal transduction pathway that effects NaCl tolerance through the regulation of Na+ influx and efflux. A truncated form of the catalytic subunit and the regulatory subunit of yeast CaN were coexpressed in transgenic tobacco plants to reconstitute a constitutively activated phosphatase in vivo. Several different transgenic lines that expressed activated CaN also exhibited substantial NaCl tolerance, and this trait was linked to the genetic inheritance of the CaN transgenes. Enhanced capacity of plants expressing CaN to survive NaCl shock was similar when evaluation was conducted on seedlings in tissue culture raft vessels or plants in hydroponic culture that were transpiring actively. Root growth was less perturbed than shoot growth by NaCl in plants expressing CaN. Also, NaCl stress survival of control shoots was enhanced substantially when grafted onto roots of plants expressing CaN, further implicating a significant function of the phosphatase in the preservation of root integrity during salt shock. Together, these results indicate that in plants, like in yeast, a Ca2+- and calmodulin-dependent CaN signal pathway regulates determinants of salt tolerance required for stress adaptation. Furthermore, modulation of this pathway by expression of an activated regulatory intermediate substantially enhanced salt tolerance.  相似文献   
8.
背景 感染性休克患者存在肾脏血液灌注异常,严重时可诱发急性肾损伤(AKI),严重威胁患者生命安全;彩色多普勒超声(CDU)可用于评估肾脏血流变化,但有关其在感染性休克患者AKI评估中价值的研究较少。目的 通过CDU评价感染性休克患者AKI的发生情况及其血流动力学改变。方法 选取2019年6月至2021年7月徐州市中心医院收治的105例确诊为感染性休克的患者并纳入感染组,选取同期健康体检者58例并纳入对照组,收集受试者一般资料。采用CDU检查受试者肾脏血流动力学指标[肾动脉管腔内径(D)、收缩期血流峰值速度(Vs)、舒张末期血流速度(Vd)、阻力指数(RI)、搏动指数(PI)],比较感染组与对照组的一般资料及肾脏血流动力学指标。根据感染组患者入院72 h内发生AKI与否将其分为AKI组及非AKI组,比较AKI组与非AKI组肾脏血流动力学指标。应用受试者工作特征(ROC)曲线分析肾脏血流动力学指标对感染性休克患者发生AKI的预测价值。应用单因素分析及多因素Logistic回归分析探讨感染性休克患者发生AKI的影响因素。以AKI由轻到重的程度将患者分为AKIⅠ组、AKIⅡ组、AKIⅢ组,比较...  相似文献   
9.
10.
Seventeen cases of otitis media caused by Mycobacterium chelonae were detected among patients seen at a single ear-nose-and-throat (ENT) office (Office A) in Louisiana between May 5 and September 15, 1987. All the patients had a tympanotomy tube or tubes in place or had one or more tympanic-membrane perforations, with chronic otorrhea that was unresponsive to standard therapy with antimicrobial agents. Middle-ear exploration in six patients revealed abundant granulation tissue; multiple granulomas and acid-fast bacilli were demonstrated on a section of tissue from one patient with a nonhealing mastoidectomy incision. Thirteen of the 14 ear isolates obtained from patients seen in Office A had the same unusual pattern of high-level resistance to aminoglycosides. M. chelonae and other nontuberculous mycobacteria were recovered from several sources of water in Office A, as well as in another ENT office (Office B) in a neighboring city that was visited by the index patient. Only one additional case was detected in Office B during the same period. Otologic instruments in Office A were cleaned in an ultrasonic bath with tap water and a liquid detergent; the contents of the bath were changed only once weekly. Instruments in Office B were placed in boiling water between patient examinations. This outbreak establishes M. chelonae as an agent of otitis media and underscores the need for high-level disinfection or sterilization of ENT instruments between examinations to prevent the transmission of this organism to patients in the office setting.  相似文献   
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