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排序方式: 共有774条查询结果,搜索用时 15 毫秒
681.
682.
683.
M Keszler HD Modanlou DS Brudno FI Clark RS Cohen RM Ryan MK Kaneta JM Davis 《Pediatrics》1997,100(4):593-599
OBJECTIVE: To test the hypothesis that high-frequency jet ventilation (HFJV) will reduce the incidence and/or severity of bronchopulmonary dysplasia (BPD) and acute airleak in premature infants who, despite surfactant administration, require mechanical ventilation for respiratory distress syndrome. DESIGN: Multicenter, randomized, controlled clinical trial of HFJV and conventional ventilation (CV). Patients were to remain on assigned therapy for 14 days or until extubation, whichever came first. Crossover from CV to HFJV was allowed if bilateral pulmonary interstitial emphysema or bronchopleural fistula developed. Patients could cross over to the other ventilatory mode if failure criteria were met. The optimal lung volume strategy was mandated for HFJV by protocol to provide alveolar recruitment and optimize lung volume and ventilation/perfusion matching, while minimizing pressure amplitude and O2 requirements. CV management was not controlled by protocol. SETTING: Eight tertiary neonatal intensive care units. PATIENTS: Preterm infants with birth weights between 700 and 1500 g and gestational age <36 weeks who required mechanical ventilation with FIO2 >0.30 at 2 to 12 hours after surfactant administration, received surfactant by 8 hours of age, were <20 hours old, and had been ventilated for <12 hours. Outcome Measures. Primary outcome variables were BPD at 28 days and 36 weeks of postconceptional age. Secondary outcome variables were survival, gas exchange, airway pressures, airleak, intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), and other nonpulmonary complications. RESULTS: A total of 130 patients were included in the final analysis; 65 were randomized to HFJV and 65 to CV. The groups were of comparable birth weight, gestational age, severity of illness, postnatal age, and other demographics. The incidence of BPD at 36 weeks of postconceptional age was significantly lower in babies randomized to HFJV compared with CV (20.0% vs 40.4%). The need for home oxygen was also significantly lower in infants receiving HFJV compared with CV (5.5% vs 23.1%). Survival, incidence of BPD at 28 days, retinopathy of prematurity, airleak, pulmonary hemorrhage, grade I-II IVH, and other complications were similar. In retrospect, it was noted that the traditional HFJV strategy emphasizing low airway pressures (HF-LO) rather than the prescribed optimal volume strategy (HF-OPT) was used in 29/65 HFJV infants. This presented a unique opportunity to examine the effects of different HFJV strategies on gas exchange, airway pressures, and outcomes. HF-OPT was defined as increase in positive end-expiratory pressure (PEEP) by >/=1 cm H2O from pre-HFJV baseline and/or use of PEEP of >/=7 cm H2O. Severe neuroimaging abnormalities (PVL and/or grade III-IV IVH) were not different between the CV and HFJV infants. However, there was a significantly lower incidence of severe IVH/PVL in HFJV infants treated with HF-OPT compared with CV and HF-LO. Oxygenation was similar between CV and HFJV groups as a whole, but HF-OPT infants had better oxygenation compared with the other two groups. There were no differences in PaCO2 between CV and HFJV, but the PaCO2 was lower for HF-LO compared with the other two groups. The peak inspiratory pressure and DeltaP (peak inspiratory pressure-PEEP) were lower for HFJV infants compared with CV infants. CONCLUSIONS: HFJV reduces the incidence of BPD at 36 weeks and the need for home oxygen in premature infants with uncomplicated RDS, but does not reduce the risk of acute airleak. There is no increase in adverse outcomes compared with CV. HF-OPT improves oxygenation, decreases exposure to hypocarbia, and reduces the risk of grade III-IV IVH and/or PVL. 相似文献
684.
Three hundred patients, comprising of 210 men and 90 women, with internal haemorrhoids (grade I and II) were subjected to cryosurgery. There was good destruction of piles in 270 (90%) patients while in 30 (10%) patients residual pile mass was present requiring further treatment The result was compared with 100 patients of grade II haemorrhoids who underwent formal haemorrhoidectomy during the same period. It was observed that rate of complications was lower in those who underwent cryosurgery.KEY WORDS: Cryosurgery, Haemorrhoids 相似文献
685.
D GANGULY JM BORCAR RS RAJAN V RAVISHANKAR MR WACHRAY KS RAO 《Medical Journal Armed Forces India》1996,52(3):141-144
Twelve cases of intracardiac tumours operated during the period 1975 to 1994 are presented. There were 8 males and 4 females in the age range of 18 years to 64 years. Tumours were located in the left atrium in 10 patients and in the right atrium in 2 patients. Standard cardiopulmonary techniques were followed. The right atrial tumours were approached through a right atrial incision while the left atrial tumours were approached through a bi-atrial trans-septal approach. One patient underwent a perineal urethrolithotomy for an impacted urethral calculus at the same sitting. Eleven of the tumour masses excised were myxomas confirmed on histopathology. The last patient, operated for synovial sarcoma of the left knee 2 years before, presented with a metastatic tumour mass in the left atrium. No deaths occurred in the series.KEY WORDS: Heart neoplasms, Heart surgery, Myxomas 相似文献
686.
Diet-induced hyperlipidaemia in baboons is similar to that inhumans. As in humans, the ratio between low density lipoprotein(LDL) and high density lipoprotein (HDL) cholesterol is a majordeterminant of atherosclerosis. Baboons, like humans and othernon-human primates, vary in their lipaemic responses to dietarylipids. By selective breeding based on variability in plasmaand lipoprotein cholesterol response to diet, lines of baboonswith high and low responses of various lipoproteins have beendeveloped. Genetic analyses suggest that lipoprotein patternsin responses to dietary cholesterol and fat are heritable. Metabolicand molecular studies of high and low LDL and HDL cholesterolresponses to dietary lipids have suggested that different mechanismsregulate plasma LDL cholesterol on the chow and on the highcholesterol-high fat (HCHF) diet. On the chow diet, plasma LDLcholesterol levels are positively associated with cholesterolabsorption and negatively associated with hepatic LDL receptorlevels and, thus, cholesterol absorption and LDL receptors seemto regulate plasma LDL cholesterol levels. However, when theanimals consume a human-like fat- and cholesterol-enriched diet,plasma LDL cholesterol levels are not associated with eithercholesterol absorption or hepatic LDL receptor mRNA levels,but are negatively associated with plasma 27-hydroxycholesterolconcentrations, hepatic sterol 27-hydroxylase activity, andmRNA levels. Hepatic sterol 27-hydroxylase activity and mRNAlevels are induced by dietary cholesterol and fat in low respondingbaboons more than in high responding baboons. Thus, the abilityto induce sterol 27-hydroxylase determines the LDL cholesterolresponse in baboons. High HDL response baboons often have highlevels of HDL1 in their plasma. Our studies suggest that theN-terminal fragment of apo C-I with 38 amino acids and a molecularweight of 4 kDa acts as a cholesteryl ester transfer inhibitorpeptide in high HDL1 baboons. The inhibitor peptide associateswith apo A-1 in HDL to produce a modified apo A-1 protein witha molecular weight of 31 kDa. The inhibitor peptide is a geneproduct and the presence of this peptide produces an antiatherogenichigh HDL1 phenotype. 相似文献
687.
688.
CS Goodman CB Coulam RS Jeyendran LA Fishel RG Roussev 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):391-391
Representing the 60 trillion cells that build a human body, a sperm and an egg meet, recognize each other, and fuse to form a new generation of life. The factors involved in this important membrane fusion event, fertilization, have been sought for a long time. Recently, CD9 on the egg membrane was found to be essential for fusion, but sperm-related fusion factors remain unknown. Here, by using a fusion-inhibiting monoclonal antibody and gene cloning, we identify a mouse sperm fusion related antigen and show that the antigen is a novel immunoglobulin superfamily protein. We have termed the gene Izumo and produced a gene-disrupted mouse line. Izumo -/- mice were healthy but males were sterile. They produced normal-looking sperm that bound to and penetrated the zona pellucida but were incapable of fusing with eggs. Human sperm also contain Izumo and addition of the antibody against human Izumo left the sperm unable to fuse with zona-free hamster eggs. 相似文献
689.
24-Hour urinary glucose excretion was measured in 43 juvenile diabetics during treatment as outpatients. In 20 children studied twice over 1-3 months there was good correlation between glucose excretion on each occasion. Subdivision of the collections into the periods 08 therefore 00-20 therefore 00 and 20 therefore 00-08 therefore 00 hours gave slightly less consistent results with correlation coefficients of 0 therefore 83 and 0 therefore 80, respectively, between the results of the repeat tests. In 37 prepubertal children, 24-hour glucose concentration and height velocity over the previous year were compared, and a highly significant negative correlation found. 10 of the 12 children with glucose excretion greater than 40 g/d had height velocities more than 1 SD below the mean for age, while only 2 of the 25 subjects excreting less than 40 g/d had height velocities more than 1 SD below the mean. The results indicate that estimation of 24-hour urine glucose excretion can be a useful index for monitoring treatment and that subdivision of the total collection may be of value in selecting the most suitable insulin regimen for the patient. 相似文献
690.