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31.
Ginsburg PB 《The Journal of American health policy》1991,1(2):10-14
The publication of proposed rules for the Medicare physician fee schedule has triggered intense controversy, especially over the level of the conversion factor. Under the Health Care Financing Administration's interpretation of the provision requiring "budget neutrality," fee levels would be at least 16 percent lower than they would have been under the current payment method. That reduction stems from projections of physician behavior in response to changes in fees and the interaction of an asymmetric transition with the budget neutrality requirement. Other interpretations would better reflect the intent of Congress and would make better policy. The relative value scale still is far from final, but the version just published shows a greater shift in payment toward evaluation and management services than the initial phase of the study by Hsiao and colleagues. 相似文献
32.
A telomian-beagle hybrid has been studied as a possible model for the hyperkinetic syndrome in children. Behavior tests showed that hybrids, like children, exhibit hyperactivity, impulsiveness, and impaired learning. Two groups of hybrid could be differentiated; the behaviour of one improved after amphetamine (responders) while that of the did not (nonresponders). Moreover hybrids were less responsive than beagles to other effects of amphetamine such as stereotyped behaviour and hyperthermia. Measurement of blood levels of amphetamine and its active metabolite p-hydroxyamphetamine (pOA) showed that hybrids form less pOA. We propose that the lesser response of hybrids to toxic effects of amphetamine is due to this difference in amphetamine metabolism. Responders showed higher peak blood levels of amphetamine than nonresponders and their improvement on amphetamine correlated with blood levels of amphetamine.Therefore high levels of amphetamine appear to be necessary for its paradoxical effect in this model. This suggests that amphetamine acts by activating both noradrenergic and dopaminergic neuronal systems in the CNS. 相似文献
33.
Hypothalamic-pituitary activity was investigated in 20 women with primary amenorrhoea, in whom gonadal dysgenesis and lower Müllerian duct anomalies had been excluded. There was no specific or uniform pattern of response to luteinising hormone-releasing hormone and no evidence of a common defect at pituitary-hypothalamic level to account for the absence of spontaneous menstruation. Six women had hyperprolactinaemia; of these five had radiological evidence of pituitary enlargement. The conventional distinction between "primary" and "secondary" amenorrhoea should be abandoned, and, in common with current practice for other endocrine glands, primary amenorrhoea should indicate an abnormality of the gonad itself and secondary amenorrhoea an abnormality that results from hypothalamic-pituitary dysfunction. 相似文献
34.
A competitive protein-binding (CPB) assay, suitable for measuring corticosterone levels in 20 mul of mouse plasma or 100 mg of brain, is described. The postnatal development of adrenocortical function was determined in C57BL/10 and DBA/1 mice by CPB assay of basal and stressinduced levels of plasma corticosterone and resting levels of brain corticosterone. Marked increases in both basal and stressed levels of plasma corticosterone were found beginning at day 12 after birth: mean basal levels rose from about 1 mug/u99 ml on day 12 to peak values of about 10-15 mug/100 ml on days 18-20, and then declined by day 30 to the 13-day level of 2.6 mug/100 ml. This pattern differs significantly from results obtained with standard fluorometric assays for corticosterone; it was determined that a major part of this discrepancy is due to the lack of specificity of the fluorometric assay. The developmental change in brain corticosterone was similar to the pattern found in plasma. Only the stress-induced levels of plasma corticosterone showed significant genetic variation, and this did not appear until about one week after the end of the relative stress-nonresponsive period. These findings should be useful in evaluating hypotheses concerning the developmental regulation of adrenocortical function and the action of glucocorticoids in regulating the biochemical differentiation of other tissues. 相似文献
35.
Emergency and elective embolotherapy of various systemic arteries in 64 patients was carried out at a tertiary centre of Armed Forces. Specific indications were haemoptysis (n=43), preoperative (n=18), haematuria (n=1), epistaxis (n=1) and chemoembolization (n=1). The procedures were performed with gelfoam pellets (n=46), gelfoam pellets and absolute alcohol (n=1), polyvinyl alcohol particles (PVA) (n=14), steel coils (n=2) and Adriamycin-in-oil emulsion (n=1). Embolotherapy resulted in complete haemostasis in 37 (82.2%) out of 45 cases of haemorrhage. In eight cases (17.8%), it resulted in significant improvement. Complete haemostasis was achieved in both cases of haematuria and epistaxis. Pre-operative embolotherapy resulted in considerable reduction of peroperative blood loss in all the cases. Chemoembolization of Hepatocellular carcinoma resulted in partial regression of the tumour. The purpose of this study was to assess the efficacy, safety and reliability of vascular embolotherapy for control of life threatening haemorrhage and preoperative reduction of lesions.KEY WORDS: Embolization, Embolotherapy, Haemorrhage 相似文献
36.
Valerie J. Flaherman Amy S. Ginsburg Victoria Nankabirwa Augusto Braima da Sa Alvaro MedelHerrero Eric Schaefer Srijana Dongol Akina Shrestha Imran Nisar Muddassir Altaf Khushboo Liaquat Benazir Baloch Najeeb Rahman Yasir Shafiq Shabina Ariff Fyezah Jehan Susan B. Roberts 《Maternal & child nutrition》2022,18(4)
In low‐ and middle‐income countries (LMIC), growth impairment is common; however, the trajectory of growth over the course of the first month has not been well characterised. To describe newborn growth trajectory and predictors of growth impairment, we assessed growth frequently over the first 30 days among infants born ≥2000 g in Guinea‐Bissau, Nepal, Pakistan and Uganda. In this cohort of 741 infants, the mean birth weight was 3036 ± 424 g. For 721 (98%) infants, weight loss occurred for a median of 2 days (interquartile range, 1–4) following birth until weight nadir was reached 5.9 ± 4.3% below birth weight. At 30 days of age, the mean weight was 3934 ± 592 g. The prevalence of being underweight at 30 days ranged from 5% in Uganda to 31% in Pakistan. Of those underweight at 30 days of age, 56 (59%) had not been low birth weight (LBW), and 48 (50%) had reached weight nadir subsequent to 4 days of age. Male sex (relative risk [RR] 2.73 [1.58, 3.57]), LBW (RR 6.41 [4.67, 8.81]), maternal primiparity (1.74 [1.20, 2.51]) and reaching weight nadir subsequent to 4 days of age (RR 5.03 [3.46, 7.31]) were highly predictive of being underweight at 30 days of age. In this LMIC cohort, country of birth, male sex, LBW and maternal primiparity increased the risk of impaired growth, as did the modifiable factor of delayed initiation of growth. Interventions tailored to infants with modifiable risk factors could reduce the burden of growth impairment in LMIC. 相似文献
37.
W Lee K A Ginsburg D B Cotton R H Kaufman 《American journal of obstetrics and gynecology》1986,155(5):999-1001
The antemortem diagnosis of amniotic fluid embolism has traditionally relied on the identification of amniotic fluid debris in the maternal circulation by central venous or pulmonary arterial catheterization. Pulmonary artery blood specimens from 14 term pregnant women with severe pregnancy-induced hypertension suggest that squamous or trophoblastic cells may be normally present in the maternal pulmonary circulation during the peripartum period and that their presence is not pathognomonic of clinically significant amniotic fluid embolism. 相似文献
38.
39.
用固相法合成了hF-GRP及其15个类似物。全部裂解均用三氟甲磺酸完成。产物总收率60%~80%。对所有合成肽进行了影响离体的小鼠垂体分泌LH的活性筛选。结果表明,当合成肽的浓度为0.05mmol/L时:(1)将hF-GRP的C端COOH变成CONH2,活性变化不大;(2)C端残基Asn14被Phe替换后刺激垂体分泌LH的活性明显高于hF-GRP;(3)Thr3被Tyr替换后片段hF-GRP(3~13)有抑制LH分泌的活性;(4)其余类似物与空白对照相似。 相似文献
40.