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71.
The suspicion of a diagnosis of Rett syndrome (RTT) is based on clinical criteria that are often not present in the first two stages of the disease, as many of its symptoms will appear at a later age. This sometimes postpones the genetic diagnosis and an early clinical intervention. We present the case of 19-months-old girl who came to the consultation because of an arrest of psychomotor development noticed 5 months earlier without change in sleep pattern, behavior, or social communication. In the observation of 1 hour videotape, she presented subtle stereotypic movements of the face and hands as well as repetitive dystonic posturing of her limbs. A genetic test confirmed the diagnosis of RTT, showing a truncating mutation in the MECP2 gene (R270X). This case confirms that stereotypic movement anomalies, albeit infrequent and subtle, are already present before the regression stage and while maintaining prehension and that, in addition, repetitive dystonic postures may occur. Recognition of these early movement disorders will improve clinicians' ability to perform an earlier diagnosis of RTT.  相似文献   
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PET with (18)F-FDG has been considered of limited value for detection of bladder cancer because of the urinary excretion of the tracer. The purpose of this study was to investigate the role of PET/CT in the detection and restaging of bladder cancer using furosemide and oral hydration to remove the excreted (18)F-FDG from the bladder. METHODS: Seventeen patients with bladder cancer (11 without cystectomy, 6 with total cystectomy and urinary diversion) underwent (18)F-FDG PET/CT from head to the upper thighs 60 min after the intravenous injection of 370 MBq of (18)F-FDG. Additional pelvic images were acquired 1 h after the intravenous injection of furosemide and oral hydration. PET/CT findings were confirmed by MRI, cystoscopy, or biopsy. RESULTS: PET/CT was able to detect bladder lesions in 6 of 11 patients who had not undergone cystectomy. These images changed the PET/CT final reading in 7 patients: Recurrent bladder lesions were detected in 6 patients, pelvic lymph node metastases in 2 patients, and prostate metastasis in 1. This technique overcame the difficulties posed by the urinary excretion of (18)F-FDG. Hypermetabolic lesions could be easily detected by PET and precisely localized in the bladder wall, pelvic lymph nodes, or prostate by CT. Seven of 17 patients (41%) were upstaged only after delayed pelvic images. CONCLUSION: Detection of locally recurrent or residual bladder tumors can be dramatically improved using (18)F-FDG PET/CT with delayed images after a diuretic and oral hydration.  相似文献   
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The effects of clindamycin on polymorphonuclear leukocytes (PMNLs) were evaluated in vitro and in vivo in an experimental model and in immunocompromised patients with and without infection. Chemotaxis, chemiluminescence, and bactericidal capacity were evaluated using PMNLs preincubated with clindamycin in different concentrations. In the three phases of the study, clindamycin at a concentration of 2 mg/L significantly increased PMNL function. In contrast, when higher concentrations were used, PMNL function was not modified and in some cases it was decreased. Our findings suggest that clindamycin, in concentrations of 2 mg/L, positively modifies PMNL function.  相似文献   
75.
We present here the clinical results with a second-generation porcine bioprosthesis, the Carpentier-Edwards supra-annular valve (CESA). Two-hundred and twenty-two CESA bioprostheses were implanted in 189 patients during a four-year period (from 1984 to 1987), either as an isolated procedure or associated to mitral or tricuspid repair. The mid-term clinical results have been evaluated after a mean follow-up of 3.4 years, being 96% complete. There were 16 in-hospital deaths (8.4%) and 6 late, potentially valve-related, cardiac deaths (1.1% patients/year). Overall, 86.7 +/- 2% of the patients were free from cardiac death at 6 years (95.1 +/- 2% of the patients surviving the operative period). Linearized rates of valve related complications were the following: 1.4% patients/year for thromboembolism (including valve thrombosis), 0.5% patients/year for treatment-related hemorrhage and 0.7% patients/year for endocarditis. We did not found any case of either intrinsic or extrinsic valve failure, unrelated to infection of thrombosis. Two patients were reoperated, one because of valve thrombosis and the other due to prosthetic valve endocarditis (reoperation rate of 0.3% patients/year). When lethal and nonlethal valve-related complications (including in-hospital deaths) were considered all together, 75.8 +/- 8.4% of the patients remained alive and free of morbid events at 6 years. When patients were grouped according to the valve replaced (aortic, mitral and multiple), best results were found with patients submitted to isolated aortic valve replacement. We conclude that the CESA bioprosthesis has an excellent mid-term clinical performance. However, longer follow-up is necessary to know if improvement in valve design and manufacturing results in increased valve durability.  相似文献   
76.
Increased amounts of brown adipose tissue have been reported to occur in association with several diseases. The objective of the present study was to determine whether brown adipose tissue accumulation is related to nutritional status. Histologic sections of periadrenal tissue prospectively obtained at consecutive autopsies from 366 adults were examined. The cases were separated into three groups: malnourished (101 autopsies), normotrophic (128 autopsies), and obese (137 autopsies), according to the Quetelet index. Of these patients, 89 had brown adipose tissue accumulation, 35 were malnourished, 32 were normotrophic, and 22 were obese. The results showed a correlation between brown adipose tissue and patient nutritional status and a higher brown adipose tissue accumulation in malnourished patients. Cardiovascular disease was the most common type of illness present in the cases with brown adipose tissue accumulation.  相似文献   
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Dipyridamole has been reported to inhibit platelet aggregation in citrate anticoagulated whole blood (WB). However, citrate may alter the response of platelets and/or the effect of antiplatelet drugs. The present study evaluates the "ex vivo" effect of dipyridamole, two hours after a single dose (3 mg/Kg) in 25 normal subjects in non-anticoagulated (native) WB and in WB anticoagulated with citrate or hirudin. We have used the BASIC anticoagulated with citrate or hirudin. We have used the BASIC wave as analytical method, which can evaluate the early steps of platelet activation with collagen in less than 1 min after venoclysis, thus allowing the study in native WB. The results show that dipyridamole significantly inhibits (p less than 0.001) platelet activation to collagen in citrated WB (66%) while the drug's effect is much lower (21%) and non-significant if evaluated in native or hirudine anticoagulated WB. These results suggest that citrate or low calcium concentration amplify the drug's platelet inhibitory action in WB and, therefore, the laboratory results may overestimate the drug's effect "in vivo".  相似文献   
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