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101.
PURPOSE: The aim of our study was to investigate internal anal sphincter electromyographic signals. METHODS: Electromyography of the internal anal sphincter was performed with platinum wire electrodes in six healthy volunteers (three males and three females), inserted under endosonographic guidance. Platinum wire electrodes were also inserted into the external anal sphincter. Activity of both the internal and external anal sphincter in a 40-second period was measured. RESULTS: Internal anal sphincter median activity was 22.1 (range, 5.5–67.6) μ V. Slow-wave activity was 47 cycles/minute (range, 34–55 cycles/minute). After inflation of a rectal balloon with air until a constant relaxation of the anal canal was obtained, a decrease in internal anal sphincter activity to 15.9 (1.2–31.3) μV as well as a decrease in slow-wave activity to 34 cycles/minute (range, 27–40 cycles/minute) was found. The original internal anal sphincter EMG was resumed after deflation of the rectal balloon. External anal sphincter median activity was 31 (range, 0.77–18.6)μV. During inflation of the rectal balloon, a reflex increase in external sphincter EMG activity was found. With the rectal balloon fully inflated a part of this increase was still present, 11.0 (1.9–24.6)μV. In some of the subjects, this increased activity was superimposed on the internal anal sphincter recordings as well. During a voluntary squeeze it was not possible to identify internal anal sphincter activity due to activity of the external anal sphincter totally overriding the internal anal sphincter signal. CONCLUSION: Precise EMG recordings from the internal anal sphincter is possible with endosonographic guidance of the electrodes, except during voluntary squeezing of the external anal sphincter.  相似文献   
102.
103.
Pericentral retinal dystrophy   总被引:1,自引:0,他引:1  
A diagnosis of pericentral retinal dystrophy was made in 28 patients from four families, all living in North Norway. Patients from two and three generations were examined, establishing the relatively benign but progressive course of the disease. The advanced stage of pericentral retinal dystrophy could not be differentiated from the advanced stage of 'classical' retinitis pigmentosa. Three families demonstrated an autosomal dominant pattern of inheritance. In one family the mode of inheritance probably was autosomal recessive. Fluorescein angiography in the initial stage of the disease was normal, without evidence of pathological changes in the pigment epithelium or choroidal vessels, indicating that the pathological process may start in the photoreceptors.  相似文献   
104.
In a double-blind, placebo-controlled sleep-laboratory study the short-term effects of cinolazepam--a recently introduced 1,4 benzodiazepine with a half-life of 9 h--on the all-night sleep, morning awakening and early morning behaviour were investigated in 20 young normal subjects, whose sleep was experimentally disturbed by nocturnal traffic noise. The latter was prerecorded on tape and reproduced by loud speakers throughout the night with a sound pressure level of 68-90 dB(A) (energy equivalent mean noise level LAeq: 79dB(A)). According to the parallel group design subjects received either a placebo or 40 mg cinolazepam. Specifically, they spent nine nights in the sleep laboratory: two adaptation nights, one baseline night on placebo, three drug or placebo nights, and three post-drug/placebo nights under traffic noise. Somnopolygraphic investigations were carried out between 22h30 and 06h00. The drug was given orally half an hour before bedtime. Each 30 sec epoch was scored according to the criteria of Rechtschaffen and Kales. In the morning the subjects were awakened by 1000 Hz tones which were increased in loudness in 10 dB steps in two minute intervals. A sleep self-rating scale for sleep and awakening quality was completed half an hour after the morning toilet. Thereafter noopsychic and thymopsychic variables were evaluated utilizing a psychometric test battery. Statistical analyses of objective sleep variables demonstrated a significant improvement of sleep maintenance after 40 mg cinolazepam as reflected by an increase of sleep efficiency, decrease of wake time (during total sleep period) and number of awakenings as compared with the placebo. Sleep architecture was only affected slightly: sleep stage S1 decreased, S2 increased, while S3, S4 and SREM (S rapid eye movement) remained unchanged. Subjective sleep quality improved significantly as well. In the mornings there were no hangover signs, neither in subjective nor in objective psychometric and psychophysiological variables. Finally, the study suggests that man can adapt subjectively to nocturnal traffic noise over one week, although the improvement of objective sleep variables over time did not reach the level of statistical significance.  相似文献   
105.
Environmental surface and personnel hand impression cultures were obtained during 13 sampling periods in the University of Virginia Pediatric Intensive Care Unit to document potential reservoirs of nosocomial pathogens. In 78 environmental cultures Staphylococcus aureus was found eight times and gram-negative bacilli ten times. The patient chart cover was the most commonly contaminated surface. Acinetobacter calcoaceticus was found in five of ten cultures positive for gram-negative bacilli. Thirty of 59 hand cultures were positive for S aureus and gram-negative bacilli; nurses and residents had both, respiratory therapists only gram-negative bacilli, and A calcoaceticus was the most commonly isolated bacterium of potentially nosocomial significance (14/30). Laboratory investigation of bacterial survival revealed that gram-negative bacilli survived on a dry formica surface from a few hours up to three days but Acinetobacter survived up to 13 days. Since A calcoaceticus has been implicated in many nosocomial infections, its long survival on a dry surface may be an additional factor in its transmission in hospitals and suggests that more attention be paid to environmental surfaces as a source of significant nosocomial pathogens.  相似文献   
106.
A cohort of 38-year-old men and women were studied for leisure time physical exercise in relation to low back pain (LBP), education, work, social class and smoking by a self-administered questionnaire. At the age of 14 years, the subjects had been interviewed by their school doctor regarding history of LBP and radiographs of the thoracic and lumbar spine were taken. The results show no positive correlation between radiographic changes and LBP in the adolescent period and decreased physical activity in adulthood. Physical activity for at least 3 h/week reduces the risk of LBP measured as lifetime, 1-year and point prevalence. Eighty-five percent of the subjects who reported taking physical exercise for at least 3 h/week had participated in sports activity almost constantly since their school days and these reported being in better condition than the rest of the cohort. Otherwise they did not have a healthier mode of life. No physical exercise during leisure time was associated with a short school education, un-skilled work, unemployment and sickness, low social class, divorce, living in an apartment and smoking. Sixty percent had never or not for many years been interested in participating in sports. Badminton and tennis were the most common sports practised (36%), followed by gymnastics (32%), ball games — soccer and team handball - (25%), running (20%) and swimming (18%). Gymnastics and swimming seem to reduce LBP significantly. Our results show a falling interest in participating in sports activities over time, with 68% of the subjects being members of an athletic association previously, but only 29% currently. Women were more physically inactive during leisure time, probably because of their dual role. Logistic regression analysis indicates that physical activity is related to a long school education, high social class and regular sports activity over time.  相似文献   
107.
This paper discusses the use of the Milgram obedience experiments and the Tuskegee syphilis study in the bioethical literature. The two studies are presented and a variety of uses of them identified and discussed. It is argued that the use of these studies as paradigms of problematic research relies on a reduction of their complexity. What is discussed is thus often constructions of these studies that are closer to hypothetical examples than to the real studies.  相似文献   
108.
The aim of the study was to determine the role of neurogenic damage to pelvic floor muscles on the outcome of Burch colposuspension. Thirty women objectively continent after Burch colposuspension and 18 women with recurrent stress urinary incontinence (RSUI) were investigated with concentric needle electrode electromyography (EMG) in both pubococcygeus muscles and the external anal sphincter muscle. Neurogenic EMG patterns were significantly more often seen in the pubococcygeus muscles in women with RSUI than in women continent after the colposuspension (P<0.05). The distribution of neurogenic EMG patterns in the investigated muscles was significantly more pronounced in women with RSUI than in continent women: at least one pubococcygeus muscle with neurogenic EMG pattern, 72% vs. 34% (P<0.05); both pubococcygeus muscles, 50% vs. 13% (P<0.05); and all three investigated muscles 41% vs. 10% (P<0.05). In conclusion, the results imply an association between the outcome of the Burch colposuspension and the occurrence of neuropathy in the pelvic floor muscles. Occurrence of neurogenic damage in the pubococcygeus muscles seems to impair the outcome of Burch colposuspension.  相似文献   
109.
Platelet count, spontaneous platelet aggregation, ADP- and collagen-induced platelet aggregation platelet adhesion, platelet volume, shape change, beta-thromboglobulin and von-Willebrand-factor have been investigated in 51 insulin dependent diabetic children without clinical signs of diabetic angiopathy. Compared to an age matched healthy control group diabetic children showed a significant enhancement of spontaneous platelet aggregation, elevated plasma levels of von-Willebrand-factor, increased platelet shape change and adhesion. No alterations could be found in ADP--and collagen--induced platelet aggregation and in beta-thromboglobulin levels. Significant correlations could be found between the total glycosylated haemoglobin concentrations (Hb A1) and spontaneous platelet aggregation, as well as between duration of diabetes Hb A1, and platelet volume. In this study we could demonstrate changes in platelet function in diabetic children without clinical signs of diabetic angiopathy. However these changes could be due to metabolic adjustment and may precede diabetic vasculopathy.  相似文献   
110.
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