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21.
OBJECTIVE: To describe the onset of Huntington disease (HD) in a patient with atypical progression of symptoms. BACKGROUND: The authors report the case of a 39-year-old man with severe cognitive impairment and diffuse cortical atrophy before the onset of motor manifestations or symptoms of an extrapyramidal movement disorder. METHOD: Clinical examinations, neuropsychologic assessments, magnetic resonance imaging, electroencephalogram, and genetic testing were conducted. RESULTS AND CONCLUSIONS: Although HD was eventually confirmed through genetic testing, chorea was not part of the clinical picture until well after the patient had developed a frank dementia, with a decline in global intellectual functioning, memory deficits, slowed information processing speed, and executive dysfunction. This case indicates HD may present with atypical clinical features in the early course of the disease, and warrants diagnostic consideration in patients with early dementia of unknown etiology.  相似文献   
22.
Brain magnetic resonance images (MRI) of 104 healthy childrenand adolescents, aged 4–18, showed significant effectsof age and gender on brain morphometry. Males had larger cerebral(9%) and cerebellar (8%) volumes (P < 0.0001 and P = 0.008.respectively), which remained significant even after correctionfor height and weight After adjusting for cerebral size, theputamen and globus pallidus remained larger in males, whilerelative caudate size was larger in females. Neither cerebralnor cerebellar volume changed significantly across this agerange. Lateral ventricular volume increased significantly inmales (trend for females), with males showing an increase inslope after age 11. In males only, caudate and putamen decreasedwith age (P = 0.007 and 0.05, respectively). The left lateralventricles and putamen were significantly greater than the rightP = 0.01 and 0.0001, respectively). In contrast, the cerebralhemispheres and caudate showed a highly consistent right greater-than-leftasymmetry (P < 0.0001 for both). All volumes demonstrateda high degree of variability. These findings highlight gender-specificmaturational changes of the developing brain and the need forlarge gender-matched samples in pediatric neuropsychiatric studies.  相似文献   
23.
All therapeutic modalities of lung cancer - surgery, radiotherapy and chemotherapy - may be controlled by radiological methods. During the week after surgery one x-ray examination of the thorax should be done every day, in order to rule out pneumonia, atelectasis, mediastinal shift etc. For radiotherapy, x-ray images can show the change in tumour volume and the occurrence of pneumonitis. For chemotherapy of oat-cell carcinoma, x-ray controls are important, because chemotherapy can be modified if the therapeutic effect is not satisfactory. For follow-up studies of treated lung cancer, x-ray examinations of the thorax are indicated every three to six months. Computed tomography bone scans and liver sonography should be employed whenever there are relevant clinical signs or symptoms.  相似文献   
24.
Unilateral intranigral injections of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and MPP+ (1-methyl-4-phenylpyridine) were given to young rats and unilateral intranigral injections of MPTP were given to old rats. MPTP in old rats and MPP+ in young rats induced ipsiversive circling for at least one week after injection and contraversive circling after the systemic administration of apomorphine; the number of D-2 receptors (Bmax) in the striatum of the injected hemisphere increased compared with that of control rats. MPTP in young rats induced only short-lasting ipsiversive circling and no contraversive circling after apomorphine; the number of striatal D-2 receptors did not increase. These results suggest that the neurotoxicity of MPTP is age-dependent in the rat, and that MPTP has neurotoxic effects on the nigrostriatal dopaminergic system in old rats and induces dopamine receptor supersensitivity in the denervated striatum.  相似文献   
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This study was designed to examine the acute response of normal arterial wall to pulsed laser irradiation. Irradiation with an Excimer or a Holmium YAG laser was performed in 15 normal iliac sites of 8 male New Zealand white rabbits. The excimer laser was operated at 308 nm, 25 Hz, 50 mj/mm2/pulse, and 135 nsec/pulse and the Ho:YAG laser was operated at 2.1 μm, 3.5 Hz, 400 mj/ pulse, 250 μsec/pulse. The excimer and Ho:YAG laser were coupled into a multifiber wire-guided catheter of 1.4 and 1.5 mm diameter, respectively. The mean luminal diameter increased similarly from 2.01 ± 0.29 to 2.46 ± 0.27 mm (P < 0.0005) and from 2.09 ± 0.53 to 2.45 ± 0.30 mm (P < 0.005) after excimer and Ho:YAG laser irradiation, respectively. Perforation occurred in 3 of 15 Ho:YAG irradiated sites and 0 of 15 excimer laser irradiated sites. The sites irradiated with excimer or Ho:YAG laser had similar histologic features, consisting of shedding of the endothelium, disorganization of internal elastic lamina, localized necrosis of vascular smooth muscle cells, and fissures in the medial layer. However, the sites irradiated with excimer laser had lower grading scores than those irradiated with the Ho:YAG laser (P<0.05). Irradiation with excimer or Ho:YAG laser of normal arteries results in: (1) vasodilation of the irradiated artery; (2) localized mechanical vascular injury, and (3) Ho:YAG laser induces more severe damage to the arterial wall than excimer. © 1993 Wiley-Liss, Inc.  相似文献   
27.
Metastatic liver disease can modify the metabolic response to critical illness. Systemic lactic acidosis may arise from an increased production due to inadequate peripheral tissue oxygen transport, altered metabolic function such as depressed pyruvate oxidation or insufficient hepatic clearing capacity due to tumor replacement of functional liver mass. Hepatic venous catheterization in a patient with extensive metastatic melanoma to the liver and adult respiratory distress syndrome indicated a marked disparity between whole body and liver oxygenation which may arise due to a markedly stepped up splanchnic oxygen utilization unmatched by a proportionate rise in regional oxygen delivery. Since some neoplasms may exhibit increased metabolic activity, it is suspected that these metastatic lesions may have contributed to the observed regional hypermetabolism thereby worsening hepatic hypoxia and exacerbating lactic acidosis. This case also illustrates the difficulties in interpreting global indicators of metabolic function and oxygenation in critically ill patients.  相似文献   
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The polymerase chain reaction (PCR) was used to detect varicella zoster virus (VZV) DNA in vesicle samples from patients with varicella and zoster. Primers and the oligonucleotide probe were chosen from the region of the immediate early gene 63. Procedures for preparing the DNA from the specimens were omitted, and the amplified DNA was directly detected in ethidium bromide-stained polyacrylamide or agarose gels, thus providing a rapid and less laborious assay. A total of 66 vesicle specimens including 3 crusts (collected on days 1-14 after the onset of exanthem) were tested by the simplified VZV-PCR, and 64 (97%) were positive. When the direct visualization of the amplified DNA was confirmed by DNA hybridization, a non-radioactive hybridization assay involving a digoxigenin-labelled oligonucleotide probe and detection by chemiluminescence proved as adequate as a radioactive hybridization assay. Thus, the VZV PCR described appears to be a useful diagnostic test for detecting and identifying varicella zoster virus.  相似文献   
30.
Extended -spectrum β -lactamases(ESBLs)aremainlyproducedbymembersofthefamilyEnter obacteriaceaewhichcanhydrolyzeβ -lactamantibi oticsincludingthethird - generationcephalosporinandaztreonam ,theESBLs- producingbacillishowedmedian -highresistancetoceftazidimeandaztreonamparticularly[1] .NowadaystheprevalenceofESBLs -producingstrainshavebeenreportedinmanyareasaroundtheworld[2 ] .ButthereisfewinformationabouttherelationshipbetweentheuseofantibioticandtheproductionofESBLs .Weperformedastud…  相似文献   
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