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81.
82.
The material for the present study comprises plaster models of 310 Copenhagen children, impressions for which were taken during the month each child attained the age of 3 years. The occlusion was related to information concerning the child's sucking habits up to the time of the study. The effect of sucking habits of sagittal occlusion was observed in the canine region and the molar region. A higher proportion of distal canine relationships was recorded in children who continued to suck dummies at the age of 3 years than among finger-suckers of children who have never sucked. In primary second molar region no significant difference was recorded between the various sucking groups. The open bite is clearly dominant among children who persist with a sucking habit.  相似文献   
83.
The expression of Mam-3 antigens in normal human endometrium and endometrial carcinomas was investigated employing the monoclonal antibodies 67D11 (anti Mam-3a), 115H10 (anti Mam-3b), and 115C2 (anti Mam-3c). Dewaxed sections of formalin-fixed, paraffin-embedded curettings of 9 proliferative-, 6 interval-, 13 secretory endometria, as well as 16 endometrial carcinomas were used. In normal cycling endometrium the Mam-3a, -3b and -3c antigens were detected at the apical membrane of surface and/or glandular epithelium only, but to a different degree. The Mam-3a antigen was only detected in the surface epithelium of 66% of proliferative and 33% of interval endometrium. The Mam-3b antigen was detected in surface and glandular epithelium of all normal endometria, but was most widespread in proliferative endometrium. The Mam-3c antigen was detected in surface epithelium of proliferative, and interval endometrium especially, and in glandular epithelium in 22% of endometria irrespective of the phase. Increased expression of Mam-3a and -3c antigens was recorded in most carcinomas. A loss of polarity of staining was seen in grade III carcinomas especially, staining of the cytoplasma was recorded in half of the carcinomas. The expression of Mam-3c antigen in carcinomas seemed to decline with increasing grade of anaplasia. All carcinomas expressed the Mam-3b antigen. The present results indicate that the Mam-3a and -3c antigens are tumor-associated antigens of endometrial carcinomas and that they might be useful as diagnostic tools in endometrial pathology.  相似文献   
84.
Ankle instability caused by prolonged peroneal reaction time   总被引:3,自引:0,他引:3  
The reaction of 15 functionally unstable ankles to sudden inversion was described by monitoring muscle activity, joint motion, and alternation of the body center of pressure. The results were compared with those of 15 stable controls. Stable and unstable subjects showed a similar reaction pattern to sudden inversion: first, a peripheral reflex action, namely, a contraction of the peronei counteracting the ankle inverting momentum, and, then, a centrally elicited pattern, namely, a flexion of the hip, knee, and ankle relieving the vertical pressure on the ankle and producing ankle eversion. Unstable subjects did not show a defect in their central processing of afferent input. In contrast, a prolonged reaction time (median 84 msec compared with 69 msec in stable subjects) suggested a partial deafferentation of the reflex stabilization of the ankle and substantiated the theory of a proprioceptive deficit being responsible for ankle instability.  相似文献   
85.
Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.  相似文献   
86.
The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality.  相似文献   
87.
Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease.  相似文献   
88.
89.
用放射配体受体结合法测定表明:克塞平对多巴胺D_1受体的亲和力较异戊塞平高近20倍。两药对其它各受体的亲和力差別不大。慢性给药后,异戊塞平和克塞平均能使大鼠脑皮层5-HT_2受体的密度显著下降,而亲和力变化不明显。这种下调5-HT_2受体的作用发生在给异戊塞平后1~2周之间,给克塞平后的2~3周之间。慢性给药3周,异戊塞平和克塞平均未使大鼠脑皮层的β受体密度及亲和力产生显著变化。  相似文献   
90.
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