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51.
目的:分析国产雷帕霉素洗脱支架治疗急性冠状动脉综合征的安全性和有效性。方法:选择2004-11/2006-02在河北大学附属医院接受冠状动脉介入治疗的急性冠状动脉综合征患者102例,其中ST段抬高型心肌梗死54例,非ST段抬高型心肌梗死28例,不稳定型心绞痛20例。根据血管情况置入国产雷帕霉素药物洗脱支架(Firebird支架),支架选择原则为:支架长度应覆盖病变两端;血管直径:支架直径=1∶1.1。所有患者术前3d均口服阿司匹林100mg,氯吡格雷75mg,术中推注肝素8000 ̄10000U,手术每延迟1h,补充肝素1000u,术后皮下注射低分子肝素5 ̄7d;服用氯吡格雷75mg,1次/d,共服用9 ̄12个月,并长期服用阿司匹林100mg,1次/d。随访情况:术后6个月时随访64例;7个月时随访26例;8个月时随访12例;平均随访6.8个月,患者出院后定期进行门诊随访,记录一般情况及严重心脏不良事件(包括急性、亚急性、迟发支架内血栓形成;再发心肌梗死;急诊冠状动脉旁路移植术;死亡),术后6 ̄8个月行冠状动脉造影评价支架内再狭窄情况。并观察材料及宿主反应。结果:102例患者经皮冠状动脉介入治疗治疗均获得成功,共治疗靶血管102支,置入Firebird支架116枚,术中3例ST段抬高型心肌梗死患者出现无复流现象,2例发生室颤,电转复恢复窦性心律,3例因分支受压,出现心绞痛症状。术后4例出现穿刺部位血肿,经重新加压压迫后好转。随访6 ̄8个月所有患者未发生严重心血管事件;42例(41.2%)患者术后6 ̄8个月行冠状动脉造影复查,无一例发生支架内再狭窄。随访期间所有患者无全身毒性及超敏反应发生,生物相容性好。结论:国产药物洗脱支架治疗急性冠状动脉综合征安全,有效。  相似文献   
52.
利用硝苯啶溶液对光不稳定的性质,在波长350nm处测其光照前后的吸收度差值(△A),△A与硝苯啶乙醇溶液浓度在10~60μg/ml范围内呈线性关系。使用本法对硝苯啶片进行了含量测定,并对其类似物进行了干扰试验,排除了组分的干扰。该法的精密度日内为1.3%,日间为1.9%,平均回收率为99.96%。方法简便、快速,不需色谱等分离手段即可达到分析目的,专一性、重复性均较好,是分析硝苯啶制剂的一种新途径。  相似文献   
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Background and purpose:

5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT3 receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect.

Experimental approach:

Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current (Isc) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay (elisa). Immunohistochemical techniques were used to study the expression of 5-HT3 receptors, somatostatin and somatostatin receptors in colonic tissue.

Key results:

In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT3 receptor antagonists enhanced 5-HT-induced increases in Isc. However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT3 receptor antagonists inhibited 5-HT-induced ΔIsc. Pretreatment with a somatostatin-2 (sst2) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced ΔIsc. Combination of sst2 and 5-HT3 receptor antagonists did not cause further enhancement of 5-HT-induced ΔIsc. Moreover, both sst2 and 5-HT3 receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT3 receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT3 receptors on submucosal somatostatin neurons and of sst2 receptors on colonic mucosa.

Conclusion and implications:

Activation of neuronal 5-HT3 receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons.  相似文献   
55.
敏定偶用于35岁以上妇女的疗效、安全性和周期控制   总被引:11,自引:0,他引:11  
<正> 口服避孕药在投放市场之初,应用于各种年龄段的妇女。然而资料显示早期使用的高剂量口服避孕药会增加心肌梗塞的发病率;在1975年,美国食品药物管理局(FDA)不建议40岁以上的妇女服用避孕药,对30岁以上的吸烟妇女建议她们要么停止吸烟要么改换避孕方式。随着研究的进一步深入及低剂量口服避孕药的问市,已证实任何年龄的非吸烟  相似文献   
56.
The Allen Cognitive Level Screen is a quick screening test to assess the cognitive functions of people with cognitive impairments or psychiatric disabilities. The purposes of the study were to translate the Allen Cognitive Level Screen into Cantonese and to gather evidence of the reliability of the translated version. Translation was performed by three bilingual occupational therapists. A panel of another five bilingual occupational therapists verified the accuracy of translation. Thirty randomly selected Cantonese‐speaking healthcare workers performed the Cantonese version of the Allen Cognitive Level Screen. Results suggested that the test seemed to be accurately translated. Inter‐rater reliability and the test–retest coefficient of the Cantonese version of the Allen Cognitive Level Screen were 0.98 and 0.73 (test–retest interval = 28.3 days) respectively. Future research should be directed towards further exploring the psychometric properties and clinical application of the Cantonese version of Allen Cognitive Level Screen. Copyright © 2001 Whurr Publishers Ltd.  相似文献   
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58.
OBJECTIVE The aim of this study was to provide a comprehensive benchmark of 30-day ventriculoperitoneal(VP)shunt failure rates for a single institution over a 5-year study period for both adult and pediatric patients,to compare this with the results in previously published literature,and to establish factors associated with shunt failure.METHODS A retrospective database search was undertaken to identify all VP shunt operations performed in a single,regional neurosurgical unit during a 5-year period.Data were collected regarding patient age,sex,origin of hydrocephalus,and whether the shunt was a primary or secondary shunt.Operative notes were used to ascertain the type of valve inserted,which components of the shunt were adjusted/replaced(in revision cases),level of seniority of the most senior surgeon who participated in the operation,and number of surgeons involved in the operation.Where appropriate and where available,postoperative imaging was assessed for grade of shunt placement,using a recognized grading system.Univariate and multivariate models were used to establish factors associated with early(30-day)shunt failure.RESULTS Six hundred eighty-three VP shunt operations were performed,of which 321 were pediatric and 362 were adult.The median duration of postoperative follow-up for nonfailed shunts(excluding deaths)was 1263 days(range 525-2226 days).The pediatric 30-day shunt failure rates in the authors'institution were 8.8%for primary shunts and 23.4%for revisions.In adults,the 30-day shunt failure rates are 17.7%for primary shunts and 25.6%for revisions.In pediatric procedures,the number of surgeons involved in the operating theater was significantly associated with shunt failure rate.In adults,the origin of hydrocephalus was a statistically significant variable.Primary shunts lasted longer than revision shunts,irrespective of patient age.CONCLUSIONS A benchmark of 30-day failures is presented and is consistent with current national databases and previously published data by other groups.The number of surgeons involved in shunt operations and the origin of the patient's hydrocephalus should be described in future studies and should be controlled for in any prospective work.The choice of shunt valve was not a significant predictor of shunt failure.Most previous studies on shunts have concentrated on primary shunts,but the high rate of early shunt failure in revision cases(in both adults and children)is perhaps where future research efforts should be concentrated.  相似文献   
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