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141.
This study provides a map of variations of families and some of the core relationships between types of family and the mental health of children. Family types in a poor, black urban community were defined in terms of the adults present at home. The resulting taxonomy is based on two populations: half of the community's 1964 first-grade children and families and the entire 1966 first-grade children and families. Eighty-six family types were found, falling into ten major classes. Family type was found to be strongly related over time to the child's social adaptational status (SAS) and his or her psychological well-being. The results suggest that (1) mother alone families entail the highest risk in terms of social maladaptation and psychological well-being of the child; (2) the presence of certain second adults has important ameliorative functions--mother/grandmother families being nearly as effective as mother/father families, with mother/stepfather families similar to mother alone in regard to risk; and (3) the absence of the father was less important than the aloneness of the mother in relation to risk.  相似文献   
142.
The effect of carboxylic acids on the permeation of chlorpromazine was investigated through a dimethyl polysiloxane nonpolar membrane. The permeability of the diffusate, at pH 5.8, increases considerably in the presence of carboxylic acids or phosphate, probably due to an ion-pair formation between the relative anions and chlorpromazine.  相似文献   
143.
144.
The pineal gland in the rat exhibits a diurnal rhythm in activity of the enzyme serotonin N-acetyltransferase (N-AT) with peak values during the dark period of a diurnal lighting schedule approximately 100-fold those during the light period. After blinding the rhythm becomes free-running. It is abolished by partial hypothalamic deafferentation with a knife cut made caudal to the optic chiasm. Water deprivation for 23 h daily has no effect on the pineal rhythm in either intact, blinded or deafferented animals. In contrast to this, there is a diurnal rhythm in hippocampal formation in norepinephrine content which can be entrained by a water deprivation schedule in both intact and blinded animals. These observations indicate that in the same animals 1 diurnal rhythm may remain entrained to the light-dark cycle while another rhythm is entrained to a secondary synchronizer, the water deprivation schedule.  相似文献   
145.
The relationships between luminal hydrostatic pressure and fluid transport by dog jejunum in vivo studied as a sheet in the Wells clamp were compared with quantitative predictions from a model proposed for the mechanism of the secretion produced by elevated venous pressure. According to the model, the secretion produced by increasing venous pressure and the secretion produced by negative luminal pressure are both passive filtrates contingent on a transepithelial pressure of a few centimeters of H2O. We consider that the agreement between the observed and predicted responses to luminal pressure provides strong support for the model. In particular, a) the observations displayed a predicted gross asymmetry in rates of fluid transfer with isotonic fluids depending on whether the luminal pressure was positive or negative; b) the observed magnitude of the negative luminal pressure required for the onset of secretion agreed with predictions; and c) the secretion contained significant amounts of protein at about 25% of the plasma concentration.  相似文献   
146.
147.
IMV is a combination of spontaneous and mechanical ventilation. For numerous reasons, IMV is potentially more advantageous than conventional techniques. By maintaining spontaneous breathing, mechanical augmentation can be titrated to adjust alveolar minute ventilation levels to normal, thereby decreasing the incidence of respiratory alkalemia. There are major differences between the cardiopulmonary effects of IMV and conventional mechanical ventilation. Spontaneous inspiration decreases Ppl and results in better distribution of inspired gas, a better V/Q, and less physiological dead space. In addition, transmural filling pressures, venous return, and cardiac output are more normal than during conventional mechanical ventilation. Maintenance of spontaneous ventilation lowers mean Paw and pulmonary vascular resistance. If venous admixture occurs, it can be minimized by titrating PEEP. Thus, more effective therapy for hypoxemia is possible. If spontaneous breathing is to persist and be efective, work-of-breathing must be minimized. This can be accomplished best when a continuous flow of gas provides optimal CPAP to maintain FRC and to minimize the effects of decreased compliance without depressing cardiac function.  相似文献   
148.
1 Ephedrine plasma levels have been measured in ten asthmatic patients given a singel dose of ephedrine hydrochloride (22 mg) along and in combination with theophylline and a barbiturate. 2 Pharmacokinetic assessment of the data indicated no significant intra-subject changes in kinetic parameters before or after chronic treatment with ephedrine HCl (11 mg three times a day) alone or in combination. 3 Tolerance to these therapeutic doses, if it occurs, is therefore not disposition-related but rather to pharmacodynamic changes.  相似文献   
149.
Affinity chromatography on agmatine-Sepharose was used for the separation of two active forms of urokinase (EC 3.4.99.26) from partially purified human urinary urokinase. The approximate molecular weight of the heavier form was 47 000 and of the lighter 33 400. Both forms were homogeneous by sodium dodecyl sulfate gel electrophoresis and by 3H-labeled diisopropylphosphorofluoridate and 14C-labeled p-nitrophenyl-p'-guanidinobenzoate incorporation studies. The 33 400 mol. wt. form had a single chain, and the 47 000 mol. wt. form had two chains (33 100 and 18 600 mol. wt.) linked by disulfide bonds. The specific activity of the heavier form was 104 000 CTA units/mg protein, compared with 226 000 units/mg for the lighter form but the activities per mmol of active site (molar activities) of the two forms were almost identical (9.6-10(9) and 10.2-10(9) CTA units/mmol). Isoelectric focusing on gels showed that the 47 000 material contained one major subform with a pI of 8.60 and a minor subform with a pI of 8.90, while the 33 400 material had three major subforms with pI values of 8.35, 8.60 and 8.70, respectively, and a minor subform with a pI of 8.05. 3H-labeled diisopropylphosphorofluoridate incorporation studies revealed an active-site serine residue in the heavy chain.  相似文献   
150.
Formal program evaluation is an important resource for health care decision making. It is necessary in situations where traditional organizational evaluative capabilities an no longer meet the requirements of the job at hand.  相似文献   
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