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41.
The authors present a four electrode rheographic technique for simiquantitative continuous measurement of CBV, by examining changes in cerebral tissue impedance induced by changes in blood content of the brain parenchyma. Correlation between the data obtained and ICP measurements permits conclusions regarding the behaviour of the cerebral blood bed. pCO2 regulates CBV, and the phenomenon is reversible according to a hystereris shaped time course in acute experiments. The rebound of ICP after sudden injections of CSF into the cisterna magna is of a vasogenic nature. Changes in CSF volume induce contrary changes in CBV. Pharmacological effects can be studied. The validity of the method is discussed.  相似文献   
42.
In this review, the clinical reality, the statistical risk, and the frequency of thromboembolism in pill users are evaluated, 6 cases described, and premonitory signs, treatment, and etiology are discussed. Clinically these thromboembolisms appear in unlikely subjects and unusual bodily locations such as the mesenteric veins, without warning. The risks are 8-11 times higher for pulmonary thrombosis, 3-6 times higher for myocardial infarction, based on previously used higher dosed pills. The frequency is about .5-1/1000, or 500-1000/year in France. Some of the cases described used pills with less than .05 mg estrogen, some were heavy smokers, 1 woman died, 1 had a lower extremity amputation, and 1 woman had demonstrated IgG lamda antibodies against ethinyl estradiol. Premonitory signs are rare, and unsually ignored. The immediate action is to stop the pill and start anticoagulants. The cause of these disorders is not known in detail, but is presumed to be estrogens, therefore, low-dose pills, i.e., those with .05 or .03 mg ethinyl estradiol, should be used if possible. Other risk factors are surgery, age, immobilization, history of vein disorders, smoking, hyperlipidemia, hypertension, especially since the pill potentiates hypertension, hyperlipidemia, and hypercoagulation. Some mechanisms proposed are hyperlipidemia, disturbed blood coagulation factors, decreased fibrinolysis, alterations in the blood vessel endothelium and immunity against the estrogen in the pill.  相似文献   
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44.
Colon atresia is a rare cause of intestinal obstruction in the neonate and requires early diagnosis and prompt surgical treatment. It is impossible in the neonate to differentiate colon atresia from other forms of obstruction at the time of initial presentation. The diagnosis is confirmed roentgenographically, including views of the abdomen and contrast barium enema series. Lesions proximal to the splenic flexure are treated with initial resection of the atretic segment and a primary anastomosis. Those lesions distal to the splentic flexure are managed initally with a diverting loop colostomy with subsequent staged resection and anastomosis.  相似文献   
45.
Fifth patients had bilateral intracapsular cataract extractions with a peripheral iridectomy in one eye and a sector iridectomy in the opposite eye. There was no difference in photophobia between the two eyes in 78% of patients. Twelve percent of the patients had greater photophobia in the eye with the peripheral iridectomy, and 10% had greater photophobia in the eye with the sector iridectomy.  相似文献   
46.
Purified Semliki forest virus in aerosols is inactivated rapidly at 40% and above 70% relative humidity. At all humidities tested the decay of virus infectivity runs parallel with the decrease in hemagglutination activity, whereas the biological integrity of the virus ribonucleic acid is preserved. Also, free infectious ribonucleic acid is stable after spraying at all relative humidities. Evidence is presented for the hypothesis that above 20% relative humidity, virus inactivation in aersols is mainly due to surface-dependent factors, damaging the virus coat.  相似文献   
47.
Pulmonary effects of chronic exposure to airborne cadmium   总被引:1,自引:0,他引:1  
In haemoglobinometry grave errors are still being made even though an internationally accepted standardized method is available for the determination of the haemoglobin content of blood. Up to the present only haemiglobincyanide reference solutions have been available on a wide scale to check the measuring stage of the standardized haemiglobincyanide method. These reference solutions are shown to remain stable, under proper storage conditions, for more than 10 years. Concentrated haemoglobin solutions have become available recently, offering the possibility to control the dilution and conversion steps of the haemiglobincyanide method. Such a solution is shown to remain stable, under proper storage conditions, for at least a year. Using both haemiglobincyanide reference solutions and concentrated haemoglobin solutions, as well as having the possibility of checking the cyanide content of the reagent used, an acceptable intra-laboratory control program may now be set up.  相似文献   
48.
A 17 year-old male, who was mentally and bodily retarded from the age of 7 years. At the age of 16 years, several neurological signs appeared. Pathologically, there was widespread myelin loss and tissue sponginess in the white matter of the cerebrum and cerebellum, bilaterally and symmetrically. A great many Alzheimer type II glia and Opalski glia were widely distributed in the cerebral cortex and the basal ganglia. Despite severe destruction of the white matter, mesenchymal and gliofibre proliferation were not noticed. In the liver, Laennec's cirrhosis and a great many copper granules in the cytoplasm of the parenchymal cells were identified. From the above mentioned findings the present case, being a new type, could be called "Demyelinating type of Wilson's disease".  相似文献   
49.
Replies to L. E. Beutler et al (see record 1973-31675-001) who presented data in defense of using the number of patients rather than the number of therapists as the unit of analysis for assessing the reliability of process psychotherapy variables. The present paper presents data suggesting that the Beutler et al interpretation of their research findings is not valid. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
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