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目的:应用功能磁共振成像观察脑卒中后及康复过程中,在相应脑内运动功能区激活的变化情况,探讨不同运动模式下皮质功能再塑的表现。方法:选取2003-02/10大庆油田总医院康复科住院的皮质下脑梗死患者8例,在发病后1周始进行连续两个月的康复。在康复前、康复1,2个月时运用Brunnstrom分级、Caroll上肢功能量表(0 ̄100分,评分越高功能越好)对其手功能进行评价,并采用GEMR/iHiSpeed1.5超导磁共振扫描机进行磁共振成像功能激发检查。患者用病手执行简单运动(快速连续的拇指与其他各指的对指动作)、随意运动(用病手摸不同形状的木块),获得脑功能激发图像,观察脑内相关功能区的激活情况。结果:8例受试者均进入结果分析。①康复后所有患者Brunnstrom分级和Caroll上肢功能评分均较康复前有明显改善。②病手简单运动时脑内相关功能区的激活情况:8例受试者7例在损伤后早期手指不能对指,所以没有激活;M1,SMA,PMA脑区和小脑呈现单侧激活-双侧激活-单侧激活的变化过程;随着运动功能恢复,脑内激活数目随时间呈下降趋势,几乎接近正常人脑功能表现。③病手随意运动时脑内相关功能区的激活情况:实验中发现引起的运动相关功能区的激发情况变化多样,规律性较差,但其中5例受试者表现出损伤后激发数目明显减少,许多对运动起决定性支配作用的功能区亦不激活;随着运动功能恢复,激发区数目呈上升趋势,同损伤后简单运动的激活表现。结论:①脑卒中后病手经过康复治疗简单运动恢复较好,康复治疗2个月后脑内运动功能相关区域激活的规律已同正常人。②脑卒中后病手随意运动恢复较困难,康复治疗后不如简单运动恢复好,脑内相关运动功能区激活无明显的规律性。随着运动功能的恢复,脑内相应的运动功能区激活增多。  相似文献   
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Background  

Several malaria risk maps have been developed in recent years, many from the prevalence of infection data collated by the MARA (Mapping Malaria Risk in Africa) project, and using various environmental data sets as predictors. Variable selection is a major obstacle due to analytical problems caused by over-fitting, confounding and non-independence in the data. Testing and comparing every combination of explanatory variables in a Bayesian spatial framework remains unfeasible for most researchers. The aim of this study was to develop a malaria risk map using a systematic and practicable variable selection process for spatial analysis and mapping of historical malaria risk in Botswana.  相似文献   
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Functional characteristics of electrically stimulated quadriceps muscles of patients with multiple sclerosis (MS) were determined to investigate whether adaptations in muscle properties contribute to the higher fatigability of these patients. The estimated maximal isometric force generating capacity of MS patients was only 11.2% (P < 0.05) lower than control subjects. However, the patients were only able to voluntarily exert 75 +/- 22% (n = 12) of their maximal capacity, against 94 +/- 6% (n = 7) for the control subjects. There were no differences in muscle speed, suggesting that muscle fiber distribution was not different in the MS patients due to reduced muscle usage. During a series of repeated contractions, greater decrements occurred in isometric force and in maximal rate of force rise in the MS patients (by 31.3 +/- 10.3% and 50.1 +/- 10.0%, respectively; n = 13) than control subjects (23.8 +/- 6.6% and 39.0 +/- 8.1%, n = 15), suggesting a lower oxidative capacity. The results indicate that increasing the mass of their muscles by training may help to reduce the excessive muscle fatigue of MS patients.  相似文献   
26.
Gangrenous cholecystitis is a serious complication of acute cholecystitis and is associated with increased morbidity and mortality rates. We report a case in which the diagnosis was suggested by ultrasound, but cholecystectomy delayed due to atypical clinical presentation and a false negative radionuclide biliary scan.  相似文献   
27.
Demographic, clinical and laboratory data were retrospectively collected from records of 146 cases of CT fluoroscopy‐guided chemical lumbar sympathectomy for the palliation of inoperable peripheral vascular disease (PVD) between January 1997 and August 1999. Of these, 16% had claudication, 39% had rest pain and 44% had ischaemic ulcers or gangrene. Seventy‐three percent of elective cases were outpatients. At 3 months, 27 cases were lost to follow up, leaving 119 cases. Within 3 months, improvement, defined as doubling of the walking distance, cessation of rest pain or healing of ulcers, occurred in 30.3% of cases. No change was observed in 45.4% of cases and 24.3% of cases deteriorated. Patients with ulcers or gangrene had significantly poorer results than those without any ischaemic lesions, as only 19% versus 39% of patients improved (P < 0.05). The presence of hypertension, diabetes mellitus, hyperlipidaemia and smoking had no value in predicting clinical outcome (P > 0.05). There were no major complications noted. CT fluoroscopy‐guided chemical lumbar sympathectomy is safe and effective, with a complication rate of less than 1%, and efficacy of at least 30% measured within 3 months. It is a simple and minimally invasive procedure, easily performed on an outpatient basis. CT fluoroscopy‐guided chemical lumbar sympathectomy should be considered for all patients in the early stages of inoperable PVD.  相似文献   
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OBJECTIVE: To investigate the causes of fever in subarachnoid hemorrhage (SAH) and examine its relationship to outcome. BACKGROUND: Fever adversely affects outcome in stroke. Patients with SAH are at risk for cerebral ischemia due to vasospasm (VSP). In these patients, fever may be both caused by, and potentiate, VSP-mediated brain injury. METHODS: The authors prospectively studied patients admitted to a neurologic intensive care unit with nontraumatic SAH, documenting Hunt-Hess grade, Fisher group, Glasgow Coma Score, bacterial culture data, daily transcranial Doppler mean velocities, and maximum daily temperatures. Patients were classified as febrile (temperature above 38.3 degrees C for at least 2 consecutive days) or afebrile (no fever or isolated episodes of temperature above 38.3 degrees C). VSP was verified by either transcranial Doppler or angiographic criteria. Rankin scale scores on discharge were dichotomized into good (0 to 2) or poor (3 to 6) outcomes. RESULTS: Ninety-two consecutive patients were studied. Thirty-eight patients were classified as febrile. No source for infection was found in 10 of 38 (26%) patients. In a multivariate analysis, three variables independently predicted fever occurrence: ventriculostomy (OR, 8.5 [CI, 2.4 to 29.7]), symptomatic VSP (OR, 5.0 [CI, 1.03 to 24.5]), and older age (OR, 1.75 per 10 years [CI, 1.02 to 3.0]). Poor outcome was related to fever (OR, 1.4 per each day febrile [CI, 1.1 to 1.88]), older age (OR, 1.64 per 10 years [CI, 1.04 to 2.58]), and intubation (OR, 21.8 [CI, 5.6 to 84.5]). CONCLUSION: Fever in SAH is associated with vasospasm and poor outcome independently of hemorrhage severity or presence of infection.  相似文献   
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