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Computed tomography (CT) was performed in 14 cases of tuberculous meningitis (TBM), 12 of which were examined during the acute phase of the disease. CT findings in these cases included internal hydrocephalus (6/12), internal combined with external hydrocephalus (2/12), focal lesions consistent with localized encephalitis (3/12), diffuse brain edema (1/12), and middle cerebral artery infarction (1/12). In comparison to 32 cases of nonspecific bacterial meningitis, internal hydrocephalus was found significantly more often in TBM than in nonspecific meningitis (p less than 0.01) making CT an additional tool for the differentiation of these conditions in doubtful cases. In addition, CT features of 2 cases of cerebral tuberculoma are presented.  相似文献   
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AIM: The aim of this study was to analyse possible intra- and postoperative complications and long-term results in combined orthodontic-orthognathic treatment of mentally handicapped patients compared with a control group of patients without handicap. PATIENTS AND METHODS: A group of 20 mentally handicapped patients (male = 7, female = 13) and of 102 non-handicapped patients (male = 36, female = 66) were evaluated retrospectively. The results of the two point-discrimination sensory test and the cephalometric findings of both groups were assessed. Complications during and after the operation, the results of nerve function tests and relapse rates were reported. The statistical analysis was carried out using binary logistical regression analysis with adjustment according to the diagnosis and the type of operation (p < 0.05) RESULTS: No significant differences could be found between the mentally handicapped and the non-handicapped patients. Only the nerve function test immediately postoperatively revealed differences between the two patient groups. The relapse rate in mentally handicapped patients was similar to non-handicapped patients. Forty-seven months after the operation, relapse (change in the ANB angle of more than 0.5 degrees ) was observed in four patients only (handicapped patients). CONCLUSION: Orthognathic surgical procedures in mentally handicapped patients can be carried out with a similarly high success rate as in mentally healthy patients.  相似文献   
15.

Background  

Experimental studies have shown that positron emission tomography (PET) with 13N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of 13N-labeled PET for measurement of MBF and CFR.  相似文献   
16.
Exposure to a low-level mixture of volatile organic compounds, typical of those found in new buildings, has been reported to impair neurobehavioral function in persons who have experienced sick building syndrome (SBS). Sixty-six healthy young males who had no history of chemical sensitivity were exposed for 2.75 h to a complex mixture of volatile organic compounds at 0 and 25 mg/m3. Even though subjects reported more fatigue and more mental confusion following exposure to volatile organic compounds than to clean air, performance on 13 neurobehavioral tests was not affected. Practice or learning effects were observed if administration of many behavioral tests were repeated. Further studies are needed to clarify the relationship of exposure to volatile organic chemicals, neurobehavioral performance, and subject characteristics, e.g., age, gender, and chemical sensitivity.  相似文献   
17.
During opiate anesthesia (standardized dosage of fentanyl) for operation of cerebral aneurysms after subarachnoid hemorrhage, different hemodynamic, respiratory, metabolic, and endocrine parameters were determined before (1 in Fig. 1-4), after (6), and during consecutive stages of induced hypotension (systolic blood pressure 100 mmHg (2), 90 mmHg (3), 80 mmHg (4, 5) during an interval of 20 min), comparing two groups with different vasodilating drugs. In the first group (nimo/NNP in Figs. 2-4) a constant infusion of nimodipine was applied (1.2 micrograms/kg b.w. X min-1), while sodium nitroprusside (NNP) was added in small amounts as necessary to achieve the respective values of systolic blood pressure. In the second group (NNP in Figs. 2-4) induced hypotension was done with NNP alone (maximal dosage: 8 micrograms/kg X min-1). Each group consisted of 11 patients. Additional nimodipine (in the first group), a calcium antagonist commonly recommended for preventing vasospasm and consequent neurologic deficits after subarachnoid hemorrhage, not only reduced the need for NNP, a vasodilating drug with potential toxicity, by 70%-80% as compared to the second group (Table 1). In addition, the cardiovascular situation was more stable in patients with nimodipine infusion: rapid variations of blood pressure and heart rate as well as tachyphylaxis and rebound, typical for NNP-induced hypotension, were avoided. Nevertheless, comparing the hemodynamic data at fixed stages of hypotension, there were only minor differences between both groups (Fig. 2). Reduction of blood pressure was due to a decrease in vascular resistance and was accompanied by an increase in cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
18.
Ohne ZusammenfassungMit 14 Textabbildungen.  相似文献   
19.
Ohne ZusammenfassungBei der Schriftleitung eingegangen am 12. X. 1936.-I. Mitteilung s. diese Wschr.1936 I, 1102.  相似文献   
20.
PURPOSE: To evaluate the precision of image-guided radiotherapy (IGRT) using cone-beam computed tomography (CB-CT) for volume imaging and a robotic couch for correcting setup errors in six degrees of freedom. PATIENTS AND METHODS: 47 consecutive patients with 372 fractions were classified according to whether a patient fixation device was used (pat(fix): n = 28) or not (pat(non-fix): n = 19). Prior to treatment a CB-CT was acquired and translational and rotational setup errors were corrected online without an action level using a robotic couch (HexaPOD). A second CB-CT was acquired after the correction process and after treatment in 134 and 238 fractions, respectively. RESULTS: In 17 fractions (4.6%) rotational errors > 3 degrees exceeded the motion range of the HexaPOD. Errors (3D vector) after the correction process were significantly smaller for pat(fix) compared to pat(non-fix) (p < 0.001): 0.9 mm +/- 0.5 mm and 1.6 mm +/- 0.8 mm, respectively. For pat(non-fix) the correction of rotational errors resulted in displacements of the patients on the angled couch of 0.6 mm/1 degree. Intrafractional motion further decreased precision in pat(non-fix) but not in pat(fix). CONCLUSION: Very high precision in cranial and extracranial treatment of immobilized patients was demonstrated. Without application of adequate immobilization the correction of rotational errors and intrafractional patient motion significantly decreased the accuracy of the online correction protocol.  相似文献   
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