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81.
Antenatal administration of glucocorticoids is often used to facilitate fetal lung maturation in cases of prematurity; however, the effects of betamethasone on maternal immune function have not been established. Therefore maternal immune function was assessed with the use of in vitro techniques. Transient and incomplete suppression of the proliferative response to the T-cell mitogen phytohemagglutinin was demonstrated as early as 24 hours after administration of betamethasone. The magnitude and duration of suppression showed a corresponding increase with advancing gestational age, but these effects were not cumulative and were always short-lived (less than 72 hours). No such suppression of the B-cell mitogen lipopolysaccharide was detected. The nonspecific cellular resistance to infection of maternal monocytes was determined through coincubation with the facultative intracellular pathogen Listeria monocytogenes. Increased phagocytic activity with a normal bactericidal effect was measured in the cell preparations obtained from recipients versus nonrecipients of betamethasone. Taken together, these findings clearly show that both specific and nonspecific immune function are intact in the preterm gravid woman after administration of betamethasone and should allay concerns over its use for reasons of infection control alone. 相似文献
82.
N A Evans 《British journal of sports medicine》1997,31(4):349-350
In addition to the pharmacological side effects of anabolic steroids, complications may also result from the injection technique used in self administration. Two cases are presented where anabolic steroid injections resulted in knee joint sepsis and radial nerve palsy. 相似文献
83.
Bone death in transient regional osteoporosis. 总被引:2,自引:0,他引:2
A 48-year-old man developed transient regional osteoporosis, with hip and later knee pain. He responded well to lumbar sympathectomy. The femur and tibia adjacent to the painful knee were osteoporotic, while the medial femoral condyle showed increased uptake in a bone scan. In the femoral condyle, bone histology showed areas of dead bone undergoing osteoclastic resorption, and increased bone formation. The tibial bone was histologically normal. The partial bone death in the distal femur suggests that the disorder may be related to both avascular necrosis of bone and reflex sympathetic dystrophy. 相似文献
84.
J R Evans R P L Wormald 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(6):378-386
Purpose: To analyse trends in the incidence of registered age-related macular degeneration (ARMD) in the UK since 1950 and to compare these to trends in registration of other blinding diseases —cataract, glaucoma and optic atrophy over the same time period.
Methods: Calculation of standardised registration ratios for ARMD, cataract, glaucoma and optic atrophy using published registratoin data from 1950 onwards. SRRs for each sex separately were calculated, adjusting for age in 5 year age-groups.
Results: The absolute number of people registered blind annually has more than doubled since 1950. After adjustment for age, annual registration rates for blindness have fallen over the past 40 years, particularly with respect to cataract and glaucoma. Standardised registration ratios for ARMD exhibit a different pattern, increasing, but not consistently, over the same time period.
Conclusions: These oberservations are consistent with the hypothesis that the incidence of registrable ARMD is increasing. Changes in the diagnosis and detection of this disease, however, cannot be excluded as an alternative explantation. Analysis of trends in national registration statistics may be useful for monitoring changes in the distribution of blinding eye disease in the population. 相似文献
85.
86.
The value of routine antibiotic prophylaxis was assessed in 362 women undergoing lower urinary tract instrumentation. A three-day course of a once-a-day dose of 1 g of cefadroxil was compared with a three-day course of 100 mg of nitrofurantoin three times a day, in a randomized investigator blinded placebo controlled study. Both study drugs were significantly more effective in preventing postinstrumentation urinary tract infections than placebo (p less than 0.003). Differences in efficacy between the two test drugs were not significant; however, side effects in the nitrofurantoin group were more frequent and severe than those in the cefadroxil group. Cefadroxil also offered the advantage of a once-daily dosing schedule. 相似文献
87.
Glomerulopathy and nephrotic syndrome were induced in rats by intravenous puromycin aminonucleoside. Ten days after the injection of puromycin, the animals have developed heavy proteinuria. During this phase, glomerular epithelial cell endocytosis was studied by injecting a conjugate of horseradish peroxidase and poly-L-lysine. This conjugate has been shown to be endocytosed by glomerular epithelial cells. The rats were serially sacrificed from 1 min to 24 h after this injection. Peroxidase was localised cytochemically and observed at light and electron microscopy. The early events of endocytosis in glomerulopathy (namely the binding to the plasma membrane, the membrane invagination and the formation of the early vesicles) were qualitatively similar to those in the normal. The later events (the fusion of the vesicles and their movement within the cells) were inhibited. The results show that puromycin aminonucleoside damages epithelial cell endocytotic activity and affects the later processing of the conjugate within the cells. 相似文献
88.
89.
A longitudinal study of cholinesterase changes in pregnancy 总被引:1,自引:0,他引:1
Serum cholinesterase activity was measured at intervals before, during, and after 44 pregnancies in 43 women. Three patterns of change were seen: (a) A decline in activity after conception, with no return towards pre-conception values before delivery (20 pregnancies). (b) A decline in activity accompanied by a partial or complete return to pre-conception values before delivery (19 pregnancies). (c) Either no discernible decline or increased activity during gestation (five pregnancies). We saw no association between these patterns and either the sex of the child, parity, smoking history, or alcohol intake. However, the continuous decrease in cholinesterase activity occurred in the youngest group of women, a decrease followed by an increase in the intermediate age group, and no decrease at all in the oldest group. Although not all the age-related differences quite reached statistical significance, these findings suggest that the patterns of change may be determined by some aspect of maternal physical maturity. 相似文献
90.
Hemodynamic dysfunction in obesity hypoventilation syndrome and the effects of treatment with surgically induced weight loss. 总被引:2,自引:1,他引:1 下载免费PDF全文
Obesity hypoventilation syndrome (OHS), defined as a PaO2 less than or equal to 55 mmHg and/or PaCo2 greater than or equal to 47 mmHg, was found in approximately 8% of morbidly obese patients undergoing gastric surgery for morbid obesity and was frequently associated with clinically significant pulmonary hypertension and cardiac dysfunction. Forty-six morbidly obese patients, 26 with and 20 without OHS, underwent preoperative pulmonary artery catheterization. Although the two groups had similar values for percent ideal body weight, blood pressure, and cardiac index, the OHS patients had significantly higher mean pulmonary artery pressures (PAP), p less than 0.0001, and pulmonary artery occlusion pressures (PAOP), p less than 0.01. Eighteen OHS patients were restudied 3-9 months after gastric surgery. PaO2 increased from 50 +/- 10 to 69 +/- 14 mmHg, p less than 0.0001, and PaCO2 decreased from 52 +/- 7 to 42 +/- 4 mmHg, p less than 0.0001), after the loss of 42 +/- 19% excess weight. These changes were associated with significant decreases in PAP (from 36 +/- 14 to 23 +/- 7 mmHg, p less than 0.0001) and PAOP (from 17 +/- 7 to 12 +/- 6 mmHg, p less than 0.01). Significant correlations were noted between PAP and PAOP (r = +0.8, p less than 0.0001) and PAP and PaO2 (r = -0.6, p less than 0.0001). Both left ventricular dysfunction, defined as a PAOP greater than or equal to 18 mmHg, as well as pulmonary artery vasoconstriction, defined as PAEDP greater than 5 mmHg above PAOP, contributed to pulmonary hypertension in OHS patients. In conclusion, weight loss after gastric surgery for morbid obesity significantly improved arterial blood gases and hemodynamic function in OHS patients. 相似文献