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排序方式: 共有2213条查询结果,搜索用时 15 毫秒
61.
62.
The adaptive response of whole body mineral metabolism and collagen turnover to nutritional supplementation was determined in adolescent males with Crohn disease and growth failure. Body calcium, magnesium, phosphorus, and nitrogen status was characterized in six patients before and after 3 weeks of nutritional supplementation and in five healthy age- and sex-matched controls by the metabolic balance technique; collagen turnover was assessed by urinary hydroxyproline excretion. Fecal calcium (P less than 0.05), magnesium (P less than 0.01), and nitrogen (P less than 0.01) losses were significantly greater in the Crohn disease patients compared with the controls; after dietary supplementation, only fecal magnesium excretion increased further (P less than 0.001). Approximately twofold increases in phosphorus (P less than 0.001), nitrogen (P less than 0.02), and calcium (P less than 0.05) retention occurred with nutritional supplementation, whereas the marked renal conservation of phosphorus (P less than 0.001) suggested that this mineral was a limiting nutrient. Urinary hydroxyproline excretion was reduced (P less than 0.05) compared with the control values; however, with nutritional supplementation, urinary hydroxyproline excretion increased significantly (P less than 0.02), suggesting that the soluble fraction of tissue collagen was rapidly turning over during nutritional rehabilitation. These findings suggest that the mineral deficiencies present in adolescents with Crohn disease and growth failure can be reversed with nutritional supplementation. Furthermore, the improvement in nutritional status is reflected in the restoration of collagen-containing tissues of the body. However, nutrient imbalances may be present during nutritional therapy, thereby preventing optimal recovery from malnutrition. 相似文献
63.
It has been suggested that hypermobility of the joints may predispose children to the development of arthritis or arthralgia. To determine the normal frequency of hypermobility, 260 normal schoolchildren (5 to 17 years of age) were examined. In addition, 34 patients with juvenile rheumatoid arthritis (JRA) and 32 children with juvenile episodic arthritis/arthralgia (JEA) were tested. Any child who met at least three of the following criteria was considered to have joint hypermobility: (1) passive apposition of the thumbs to the flexor aspect of the forearms; (2) passive hyperextension of the fingers so that they lie parallel with the extensor aspect of the forearms; (3) hyperextension of the elbows greater than 10 degrees; (4) hyperextension of the knees greater than 10 degrees; (5) flexion of the trunk with knees extended so the palms rest on the floor. Thirty-two (12%) of 260 normal schoolchildren and 21 (66%) of 32 with JEA had hypermobility. Further, a significantly higher proportion (23 of 126) of normal girls than normal boys (nine of 134) had hypermobility (chi 2 = 8.0, P less than 0.005). Hypermobility was not common in children with JRA. These findings support the hypothesis that hypermobility may be an important factor in the cause of JEA. 相似文献
64.
65.
O P Mathew M L Clark M L Pronske H G Luna-Solarzano M D Peterson 《The Journal of pediatrics》1985,106(5):810-813
The effect of oral feeding on breathing pattern and ventilation was studied in 19 healthy term neonates in the semiupright supine position. Ventilation was measured with a nasal flowmeter, and sucking pressure via a modified nipple that permitted milk delivery. The feeding pattern in these infants consisted of an initial period of continuous sucking followed by intermittent sucking for the remainder of the feed. A significant reduction in minute ventilation (P less than 0.01) was observed during continuous sucking, and resulted entirely from a reduction in breathing frequency (P less than 0.01). Tidal volume did not change (P greater than 0.05), but prolongation of expiration (P less than 0.01) and shortening of inspiration (P less than 0.05) were also observed. During intermittent sucking, the minute ventilation was similar to that of the control period. However, smaller but significant changes in breathing frequency and in duration of inspiration and expiration persisted during intermittent sucking. Our results document a significant reduction in ventilation during the initial part of oral feeding in term neonates, and subsequent recovery with continued feeding. Depending on the magnitude of this reduction in ventilation, cyanosis and bradycardia may develop in some infants during oral feeding. 相似文献
66.
Estrogen may be important in the hemodynamic changes that develop during pregnancy; its role in the development of vascular refractoriness to the pressor effects of infused angiotensin II is unknown. We, therefore, examined the pressor responses to six doses of angiotensin II (0.115 to 5.73 micrograms/min) in unanesthetized, nonpregnant sheep both before and after treatment with either high-dose or low-dose 17 beta-estradiol (E2) and constructed dose-response curves. Although mean arterial pressure was unchanged after the infusion of E2, cardiac output rose 28% and systemic vascular resistance fell 19% (p less than 0.001). Infused angiotensin II resulted in dose-dependent rises in mean arterial pressure before and after E2; however, the pressor response after E2 was decreased 30% to 50%. Plasma renin activity rose from 1.15 +/- 0.09 ng/ml X hr to 2.57 +/- 0.39 and 3.21 +/- 0.61 ng/ml X hr with low-dose and high-dose E2, respectively (p less than 0.05). Acutely estrogenized nonpregnant sheep develop significant alterations in both the cardiovascular and the renin-angiotensin systems in addition to decreased pressor responsiveness to infused angiotensin II. Although our findings suggest that estrogen may be important in the development of the vascular refractoriness to angiotensin II seen in pregnancy, additional studies are needed to clarify the role of each E2-induced change. 相似文献
67.
D B Cotton B Gonik T Spillman K F Dorman 《American journal of obstetrics and gynecology》1984,149(2):174-177
A study was undertaken to determine the effect of route of delivery on plasma colloid osmotic pressure. Plasma colloid osmotic pressure was measured on admission to the hospital and 8 to 24 hours post partum in 72 patients at term with uncomplicated prenatal histories. Thirty-six patients underwent uncomplicated vaginal deliveries (local anesthesia, 18; conduction anesthesia, 18) and 36 patients had cesarean sections (conduction anesthesia, 18; general anesthesia, 18). The mean (+/- SD) intrapartum colloid osmotic pressure of the overall group was 21.0 +/- 2.1 mm Hg, and it declined significantly (p less than 0.01) to 15.4 +/- 2.1 mm Hg post partum. A comparison of the intrapartum and postpartum reductions in colloid osmotic pressure between patients who underwent vaginal delivery and those who underwent cesarean section revealed no significant differences. Furthermore, the mean reductions in colloid osmotic pressure when all four groups were compared by type of anesthesia were not significantly different. Fifteen patients (20.8%) in the study had a postpartum colloid osmotic pressure of less than 13.6 mm Hg, and five (6.9%) had a postpartum colloid pressure of less than 12.5 mm Hg. Our results indicate that, for normal pregnancy, colloid osmotic pressure is uniformly lowered in the post partum and, in some cases, to levels that have been reported to be dangerously low. 相似文献
68.
Cardiovascular alterations in severe pregnancy-induced hypertension: acute effects of intravenous magnesium sulfate 总被引:2,自引:0,他引:2
The central hemodynamic effects of intravenous magnesium sulfate were studied in five patients with severe pregnancy-induced hypertension. All five patients had a Swan-Ganz and a radial artery catheter placed prior to initiation of magnesium sulfate therapy. Four grams of magnesium sulfate was given over 15 minutes followed by a continuous infusion of 1.5 gm per hour. There was a 12.5% increase in cardiac index immediately after the infusion but cardiac index returned to pretherapy values by 15 minutes after infusion. The mean arterial pressure was significantly (p less than 0.01) decreased 30 minutes after the 4 gm loading dose but had returned to baseline values by 1 hour. There were no other significant changes in any of the hemodynamic or oxygen-related variables measured. Our data confirm previous hemodynamic studies in patients with severe pregnancy-induced hypertension indicating a hyperdynamic state with large fluctuations in systemic and pulmonary vascular resistances. In addition, magnesium sulfate has been shown to have a transient hypotensive effect on mean arterial pressure, related to bolus infusion, that is not present with continuous infusion. 相似文献
69.
Accentuated cyclic activation of peritoneal macrophages in patients with endometriosis 总被引:10,自引:0,他引:10
Peritoneal fluid was collected from 107 women undergoing laparoscopic sterilization or diagnostic laparoscopy for evaluation of infertility. Cells consisting mainly of macrophages were separated and subjected to sophisticated flow fluorocytometric analysis. In this way more detailed information was obtained about activational characteristics of the pelvic macrophage population during the menstrual cycle. In normal women the macrophages, as compared to peripheral monocytes, showed evidence of elevated baseline activation, and a gradual increase in several markers occurred during the menstrual cycle. Cells increased in size, lost their ability to stain for myeloperoxidase, and increased in activity of both endoenzymes and ectoenzymes. These results suggest that female peritoneal macrophages are continuously responding to stimuli. The macrophage irritation was much more pronounced in women with mild endometriosis. This accentuated cyclic activation may represent an inflammatory response to bleeding from ectopic implants or retrograde menstruation or may be a consequence of some defect in the cell-mediated immune response in endometriosis. 相似文献
70.
M.L. Heard R.E. Bawdon D.L. Hemsell B.J. Nobles 《American journal of obstetrics and gynecology》1984,149(2):133-143
A total of 1140 aerobic and anaerobic isolates were recovered from cultures of specimens from the reproductive tracts of 435 uninfected patients who underwent elective hysterectomy. Standard minimum inhibitory concentration susceptibility studies were performed on these isolates to 13 newer penicillins, cephalosporins, and some traditional antimicrobial agents. These data were generated to evaluate the in vitro efficacy of these antibiotics for potential use in prophylaxis or as a single agent for treatment of polymicrobial infections of the female pelvis. The minimum inhibitory concentration data for each antibiotic against 16 genera of aerobic and nine genera of anaerobic bacteria were determined and were used to compare the in vitro antimicrobial activity of newer antibiotics to that of the more traditional antibiotics. Of the antimicrobial agents tested, piperacillin had the highest in vitro activity against these isolates of any antibiotic tested. 相似文献