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991.
Respiratory failure from pulmonary hypoplasia continues to be the major cause of death in newborn infants with diaphragmatic hernia. Recent investigations have suggested that postnatally induced pulmonary injury can result from excessive positive or negative intrathoracic pressure and contribute to the respiratory deterioration. Therefore, the method of thoracic drainage on the side of the diaphragmatic hernia is critical in controlling and maintaining normal intrathoracic pressure in both intrathoracic spaces. No chest tube or an ipsilateral chest tube connected to water seal, can result in either excessive negative or positive intrathoracic pressure and, therefore, both methods should be avoided. Recently, we employed a "balanced" intrathoracic drainage system which maintains the ipsilateral intrathoracic pressure within the normal physiologic range of +2 to -8 cm H2O regardless of the degree of pulmonary hypoplasia, presence of an ipsilateral pulmonary air leak, straining by the infant, or mechanical ventilation. This system is simple, requires no suction apparatus, and is easily assembled with equipment readily available within the hospital. This technique has been utilized in 18 newborn infants with diaphragmatic hernia and pulmonary hypoplasia. There have been no complications which specifically could be related to the balanced drainage system.  相似文献   
992.
The dexamethasone suppression test (DST) and response to two different antidepressant drugs (maprotiline as a specific noradrenergic, and amitriptyline as a predominantly serotoninergic drug) were investigated in 44 endogenously depressed female inpatients. The more anxious and/or agitated patients were mostly treated with amtiriptyline, the non-anxious and retarded patients with maprotiline. It was found that among maprotiline responders (N = 15) there were significantly more abnormal DSTs and postdexamethasone serum cortisol levels were significantly higher than among amitriptyline responders (N = 16). On the other hand, DST abnormalities among amitriptyline non-responders (N = 10) were similar to those among maprotiline responders. The results confirm earlier reports by Brown et al. (1980), Ettigi et al. (1983) and Fraser (1983) and indicate that abnormal DST may identify the "noradrenergic" subtype of endogenous depression and that the DST represents a good way of selecting a specific antidepressant drug for the treatment of endogenously depressed patients.  相似文献   
993.
Summary Ultrastructural changes in central nervous system (CNS) white matter of three goats affected with-mannosidosis were analyzed to further define characteristics and pathogenesis of axonal and myelin abnormalities. The variations in myelin association and contents of axonal spheroids were delineated. The occurrence of spheroids in a 96/150-day fetus documented the early development of these axonal lesions. In regions of severe myelin deficits, the presence of apparently normal axons and a reduction in the number of oligodendrocytes were confirmed. Many remaining cells in myelin-deficient regions were characterized by dark, vacuolated cytoplasm. The occurrence of internodes with myelin sheaths adjacent to internodes without myelin sheaths suggested that an axonal defect is not primarily responsible for the absence of myelin sheaths. A mild myelin deficit in the spinal cord was indicated by the presence of unmyelinated axons. Except for occasional mild cytoplasmic vacuolation, the spinal cord glial cells appeared relatively normal. The findings presented here are consistent with the hypothesis that an oligodendrocyte defect, expressed by regional differences, is a major factor in the pathogenesis of myelin deficiency in-mannosidosis.Supported by NIH grant NS-16886 to MZJ and BRSG funds from the College of Osteopathic Medicine, Michigan State University, to KLL  相似文献   
994.
The inability to image the 3rd dimension has meant a loss of valuable information, e.g., examination of an IUD in the uterine cavity. Whatever plane is examined longitudinal, transverse, or oblique the image always is a 2-dimensional tomograph producing either bars or dots. Even when the transducer lies perpendicular to the long axis of the IUD, the IUD cannot be visualized as a whole because the 1st bar produces an acoustic shadow that covers all the other bars. A technique now exists for obtaining the 3rd dimension by moving a linear array transducer over the area to be examined, which produces an endless number of images on the screen. Since the commonly used real-time scanners are not equipped with storage capacity, these images immediately fade away. This problem can be resolved by using a Polaroid camera as a storage device. The shutter is opened for the longest exposure possible, i.e., 1 second, while the diaphragm is closed. During this 1 second of exposure, the linear array transducer is "swept" over the area for examination using the compound movement technique. A second is a relatively long time, but some training is necessary before the operator can easily perform the "sweep." If the whole movement cannot be carried out in 1 second, an additional second can be used. This will rusult in a slightly overexposed picture, but these are sometimes even easier to interpret. It is important that the area be well lubricated, and the patient stop breathing for the duration of the scan. The equipment used in the study included a Picker 2000 and a Unirad real-time scanner. Both scanners were handled in the same way, and the same technique was used. Different kinds of IUDs were visualized and recorded.  相似文献   
995.
In vivo measurements of regional brain tissue/tumor pH (rpH) have been accomplished in 9 patients with primary or metastatic brain tumors using [11C]dimethyloxazolidinedione [( 11C]DMO) and positron emission tomography. Tumor rpH values ranged from 6.88 to 7.26, whereas gray matter and white matter rpH values ranged from 6.74 to 7.09 and from 6.77 to 7.03, respectively. Our results, which are consistent with reported [14C]DMO autoradiographic measurements of brain and tumor pH, suggest that the pH microenvironment of brain tumors is not more "acidic" than that of normal gray or white matter.  相似文献   
996.
The concept and taxonomy of periodic psychosis still remains in controversy for the past 100 years. In China, it was first reported by Ji, and thereafter various rinds of terminology and views were given by different authors. In the presentation, clinical investigation and follow up were carried out in 62 cases. In many of these cases, the so-called "periodic psychosis" or "phasophrenia" was early clinical features of schizophrenia or manic-depression. In those cases with apparent symptoms and signs of diencephalic function, differential diagnosis should be carried out from organic brain syndrome. In a small number of cases, their clinical manifestations, conforming to previous diagnostic criteria, might be an uncommon syndrome. It was concluded by the authors that until now periodic could be considered only as a clinical syndrome rather than a disease entity.  相似文献   
997.
Evaluating in 62 children aged from 4 months to 14 years (mean age 3 years 7 months) the correlation between the carbamazepine dosage (carbamazepine was given as the only drug in 21 cases, and as one of several drugs in 41) the authors failed to find a simple correlation. Nevertheless, most children receiving the "proper" doses had therapeutic plasma carbamazepine levels. Moreover, it was found that carbamazepine dose increase over 25 mg/kg daily caused on further rise of its plasma level.  相似文献   
998.
Analysis of consecutive emergency referrals to a community mental hospital over a 2-month period indicates that admissions are affected by a combination of demographic, clinical, and time factors. Both referrals and admissions were slightly higher in men. The mean age at referral was 44 years and of admitted patients was 30 years. Although married subjects constituted the largest group of applicants, widowers and divorced people were hospitalized more often. Both referral and admission rates were inversely correlated with education and employment. Most of the applicants came to the emergency ward accompanied by an escort. A lower rate of admissions was observed among those who came unescorted. The main indications for admission were acute psychosis and a nonspecific clinical state when the patient was defined as "dangerous to himself or to others." The family constituted the main source of referral. Peak referrals were during the morning hours, but admission rates were highest at night. Referrals decreased gradually from Sunday to Saturday, but the rate of admission was practically steady throughout the week. We conclude that the decisions for admitting a patient to a mental institute are based not only on pure psychiatric criteria, but also on an intuitive approach, in which the admitting physician's personal and emotional factors may play a role.  相似文献   
999.
31P nuclear magnetic resonance studies of a patient with phosphofructokinase deficiency in muscle provided the following new findings: First, ATP metabolism is disturbed at rest and during exercise. At rest, ATP levels are lower than normal and continue to decline during exercise. Second, exercise kinetics are normal, suggesting a normal mitochondrial fuel supply although glycolysis is blocked. Third, no "phosphate trapping" is observed during prolonged low-level exercise. Fourth, postexercise recovery is abnormally prolonged by the slow dephosphorylation of sugar phosphates, which has an in vivo half-life of about nine minutes. These findings demonstrate how muscle tissue adapts to a block in a major bioenergetic pathway.  相似文献   
1000.
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