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991.
A case of Ullrich disease was presented. The patient was a 3-year-old girl with torticollis, generalized muscle weakness and acroatonia since birth. High-arched palate, protruded calcaneus, and mild contracture of proximal joints were also recognized. Intellectual development was normal. Serum level of CPK was slightly increased. In histological and histochemical examinations of quadriceps femoris muscle, proliferated connective tissue, marked variation in the muscle fiber diameter, and a lot of degenerated and regenerated fibers were recognized. Minimal injury easily causes subcutaneous hemorrhage, but no abnormality was found in the structure of collagen.  相似文献   
992.
Behavioral state-specific changes in human hippocampal theta activity   总被引:1,自引:0,他引:1  
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms.  相似文献   
993.
We have succeeded in recording short and middle latency vestibular evoked responses in human subjects. The head was held rigidly in a special, patented head holder, constructed individually for each subject, which gripped the teeth of the upper jaw. The stimulus consisted of 2/sec steps of angular acceleration impulses produced by a special motor with intensities of about 10,000 degrees/sec 2 and with a rise time of 1-2 msec. The electrical activity was recorded as the potential difference between special forehead and mastoid electrodes having a large, secure contact area with the skin. The activity was digitally filtered and averaged in 2 separate channels by means of a Microshev 2000 evoked response system. The short latency responses, with peaks at about 3.5 msec (forehead positive), 6.0 msec (forehead negative) and 8.4 msec (forehead positive; bandpass: 200-2000 Hz; average of 1024 trials), had amplitudes of about 0.5 microV. The middle latency responses had peaks at about 8.8 msec (forehead positive), 18.8 msec (forehead negative) and 26.8 msec (forehead positive; 30-300 Hz; N = 128 trials), with larger amplitudes (about 15 microV). These responses were consistently recorded in the same subject at different times and were similar in different normal subjects. Strenuous control experiments were conducted in order to ensure that these responses are not artefacts due to the movement of conducting media (head, electrodes and leads) in the electromagnetic field of the motor and are elicited by activation of normal labyrinths.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Fourty-four narcotized rats were split into two equal groups, one being treated with nimodipine and the other with a placebo. By use of norfenefrine the blood pressure was raised to values of 150 and 180 mm Hg within the limits of the autoregulation of brain perfusion and under continuous measurement. Fifteen minutes after application of the standard tracer, horseradish peroxidase, the animals were exsanguinated using a saline perfusion and then perfusion-fixed with Karnovsky's solution. After development of the peroxidase staining the brain sections were evaluated and then allocated to their respective groups. In brain tissues from the experimental group significantly more frequent perivascular accumulations of horseradish peroxidase reaction product were found (P less than 0.001). In electron micrographs it could be seen that the tight junctions were intact and that there was a neuroendothelial transport, with horseradish peroxidase-filled vesicles, in the endothelium, muscle cells, and brain parenchyma. These vesicles represent a medium of transport for all proteins of high molecular weight and can therefore result in brain edema. It is concluded that nimodipine damages the blood-brain barrier by disturbance of the autoregulation of the cerebral blood flow.  相似文献   
995.
996.
The aim of the present study was to present data from dental care habits and knowledge of oral health in two cross-sectional studies carried out in 1973 and 1983. A random sample of approximately 1000 individuals evenly distributed in the age groups 3, 5, 10, 15, 20, 30, 40, 50, 60 and 70 years was studied for each of these two years. In the 1983-year examination 80 individuals 80 years of age were also included. All subjects were inhabitants of the community of J?nk?ping, Sweden. A questionnaire about dental care habits and knowledge was used in combination with a clinical and radiographical examination. The participants answered 23-101 questions. The same questions were raised in 1973 and 1983. For most age groups more then 80 per cent visited a dentist yearly in 1983. This yearly attendance was higher than that for 1973. In the 20-year-old group 14 per cent of the individuals received dental care in the PDS in 1973 compared to 63 per cent in 1983. The main reason to visit a dentist in 1973 was by the patient's own initiative while in 1983 the appointments were based on the dentist's initiative. The number of subjects that felt discomfort in connection with a visit to the dentist had decreased between 1973 and 1983. Knowledge about the etiology of caries had increased between 1973 and 1983 was not the case for gingivitis and periodontitis. An increase had occurred in toothbrushing frequency and the use of toothpicks and disclosing tablets but this between 1973 and 1983. In 1983, 98 to 93 per cent of the subjects in the age groups 10-30 years had been exposed to topical fluorides. The corresponding figure for 30-year-olds in 1973 was 1 per cent. It is obvious that during the period 1973 to 1983 there has been an increase in dental attendance, knowledge of dental diseases, oral health and the use of preventive measures.  相似文献   
997.
Burkitt's lymphoma, characterized by jaw and abdominal tumors, is the most common early childhood malignancy in Central Africa and well-known in the United States, with only sporadic reports coming from other countries. Considered to be the fastest growing tumor in man, it is thought to be of viral etiology with warm, humid climate and malaria regarded as co-factors. This is the first case of Burkitt's lymphoma reported from Greece.  相似文献   
998.
999.
1000.
Rapid, competitive enzymoimmunoassay for albumin in urine   总被引:1,自引:0,他引:1  
In this solid-phase competitive enzymoimmunoassay for albumin in human urine, antiserum to human serum albumin labeled with horseradish peroxidase (EC 1.11.1.7) is incubated with solid-phase-bound human serum albumin in the presence of sample or standard. Results obtained correlate well (r = 0.96) with those of an established fluoroimmunoassay. The present assay covers the range 0.9 to 200 mg/L and can be performed within 1 h. These characteristics, together with the simplicity of the assay protocol, make it very useful for monitoring low concentrations of albumin in urine. Detection of such minimal albuminuria allows initiation of therapy that may prevent development of clinical proteinuria and associated diabetic nephropathy.  相似文献   
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