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1.
D Brewster 《Tropical doctor》1989,19(3):100-4 contd
With proper nursing care and procedures, small hospitals in rural areas of developing countries can provide good neonatal care and achieve perinatal mortality rates comparable to those found at teaching hospitals. The 1st ingredient of adequate neonatology is the establishment of proper regimens for feeding, observation, and resuscitation of newborns. Even in areas where the majority of births take place at home, good neonatal care is possible as long as local risk factors are identified, all newborns are screened for these factors, and at-risk infants are referred for treatment. Factors that place infants at risk include birthweight under 2 kg or above 4 kg, delivery before 34 weeks' gestation, respiratory distress, severe birth asphyxia or trauma, jaundice, prolonged rupture of the membranes, infant not sucking or febrile, convulsions, congenital malformations, and maternal disease. 4 areas require special knowledge on the part of health personnel: the asphyxiated infant, hypothermia, hypoglycemia, and neonatal sepsis. Health workers must be familiar with proper resuscitation techniques, especially avoidance of excessive suctioning of the pharynx, and be alert to signs of hypoxic ischemic encephalopathy. Premature, small, asphyxiated, and sick infants are at greatest risk of hypothermia, a condition that can be prevented by drying and wrapping newborns immediately. Providers should be alert to signs of hypoglycemia in infants of diabetic mothers, large-for-gestational-age babies, the low- birthweight infant, and sick babies. To prevent sudden infant deaths, all sick newborns should be treated for neonatal sepsis. 相似文献
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Geert Verreck Annelies Decorte Koen Heymans Jef Adriaensen Dirk Cleeren Adri Jacobs Dehua Liu David Tomasko Albertina Arien Jef Peeters Patrick Rombaut Guy Van den Mooter Marcus E Brewster 《European journal of pharmaceutical sciences》2005,26(3-4):349-358
The aim of the current research project was to explore the possibilities of combining pressurized carbon dioxide with hot stage extrusion during manufacturing of solid dispersions of itraconazole and polyvinylpyrrolidone-co-vinyl acetate 64 (PVP-VA 64) and to evaluate the ability of the pressurized gas to act as a temporary plasticizer as well as to produce a foamed extrudate. Pressurized carbon dioxide was injected into a Leistritz Micro 18 intermeshing co-rotating twin-screw melt extruder using an ISCO 260D syringe pump. The physicochemical characteristics of the extrudates with and without injection of carbon dioxide were evaluated with reference to the morphology of the solid dispersion and dissolution behaviour and particle properties. Carbon dioxide acted as plasticizer for itraconazole/PVP-VA 64, reducing the processing temperature during the hot stage extrusion process. Amorphous dispersions were obtained and the solid dispersion was not influenced by the carbon dioxide. Release of itraconazole from the solid dispersion could be controlled as a function of processing temperature and pressure. The macroscopic morphology changed to a foam-like structure due to expansion of the carbon dioxide at the extrusion die. This resulted in increased specific surface area, porosity, hygroscopicity and improved milling efficiency. 相似文献
4.
Diagnosis Related Group (DRG) hospital payment has begun to squeeze hospitals financially and is likely to do so in the future. This study analyzed the relationship between the volume of urologic procedures by an individual urologist, hospital costs per patient, and outcome. We used a three-year DRG database of urology patients (N = 2,980) at an academic medical center to analyze these. Low-volume urologists (arbitrarily defined by us) had higher hospital costs per patient, financial losses versus profits under DRGs, and a poorer outcome when compared with high-volume urologists. Pearson correlation showed a positive relationship between cost per patient and physician volume for nonemergency patients (-0.129, p less than 0.0001) and emergency patients (-0.368, p less than 0.0001). This may have been explained (in part) by a greater severity of illness for patients of low-volume urologists. These findings suggest, however, that the volume of urologic procedures per urologist may be related to hospital resource consumption. The health care financing environment of the future should provide substantial interest in this finding for those involved in the consumption of urologic services. 相似文献
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The evolution of morphologic and biomechanical changes in reversed and in-situ vein grafts. 下载免费PDF全文
R P Cambria J Megerman D C Brewster D F Warnock J Hasson W M Abbott 《Annals of surgery》1987,205(2):167-174
A comparative study of experimental reversed (RV) and in-situ (INS) vein grafts with respect to the evolution of morphologic and compliance characteristics was done in a canine model. In addition, the compliance characteristics in a series of human INS vein grafts were recorded as a function of time after operation. At 6 months after implantation, all experimental grafts displayed well-developed intimal hyperplasia. There was no significant difference in either absolute intimal thickness (INS 0.133 +/- 0.09 mm vs. RV 0.085 +/- 0.06 mm; NS) nor in the percentage of the total wall thickness occupied by the intima when experimental INS grafts were compared with RV grafts after 6 months. Similarly, compliance values of INS and RV vein grafts were similar at all time intervals examined up to 6 months after operation. Thirty-three human INS vein grafts had a mean compliance value of 1.74 +/- 0.72 (percent radial changes per mmHg X 10(-2) at a median postoperative interval of 14 weeks. This value did not differ significantly from those measured in the INS vein grafts. Although all vein grafts examined retained their native viscoelastic properties, this study suggests that functioning human INS vein grafts are less compliant than previously suspected on the basis of prior ex-vivo and clinical studies of RV saphenous vein grafts. The purported clinical superiority of the INS vein graft cannot be explained on the basis of superior biomechanical performance or failure to develop intimal hyperplasia. 相似文献
7.
E Pop W Anderson K Prókai-Tátrai M E Brewster M Fregly N Bodor 《Journal of medicinal chemistry》1990,33(8):2216-2221
The essential amino acid, tryptophan, has been shown to lower blood pressure in rats when administered orally or intravenously. In order to potentially enhance this action, a brain-targeting chemical delivery system (CDS) approach was applied to this compound. The CDS is based on a dihydropyridine----pyridinium ion redox system, chemically analogous to the naturally occurring NADH----NAD+ system. The dihydropyridine moiety containing carrier is chemically attached to the amino group by an amide-type bonding while the carboxylic acid functionality is esterified to various alcohols. Physicochemical studies of the new derivatives were performed. The determined chromatographic Rm values indicate an increased lipophilicity for the CDSs compared to the parent compound. Oxidation stability studies performed on selected compounds using a ferricyanide-mediated method showed that the CDSs are oxidized to the respective quaternary salt forms. Activity studies performed in deoxycorticosterone acetate induced hypertensive rats, demonstrated that the delivery system for tryptophan reduced blood pressure more efficiently for a longer time than did the parent compound. 相似文献
8.
M A Brewster R S Kirby C R Feild C M Cunniff 《Public health reports (Washington, D.C. : 1974)》1992,107(3):290-296
Planning of service delivery systems for children with special health care needs would be enhanced by knowledge of numbers of cases anticipated in defined geographic areas. A method is described for predicting numbers of children who will likely have mental retardation sufficient to require special education services, based on the birth prevalence of birth defects and clinicians' estimates of the likelihood of mental retardation associated with each specific birth defect. This method is applied to the 1980-82 birth cohort of a 28-county area of south and central Arkansas, and it is compared with special education enrollment data for children ages 6 to 8 in academic year 1988-89. According to this estimate, children with birth defects may account for 32 to 56 percent of the cases of mental retardation among 6- to 8-year-olds reported by the public schools. 相似文献
9.
Paul Fernyhough Wendy J. Brewster Karin Fernandes Lara T. Diemel David R. Tomlinson 《Brain research》1998,802(1-2)
In rats with streptozotocin-induced diabetes, we measured increased (by 61%; P<0.05) mRNA for nerve growth factor (NGF) in the iris together with increased (by 82%; P<0.05) mRNA for preprotachykinin (the substance P precursor) in the trigeminal ganglion, suggesting that increased NGF was driving increased substance P gene expression. In other diabetic rats, these changes were prevented by treatment with either an antioxidant (butylated hydroxytoluene; 1% by diet) or an aldose reductase inhibitor (ARI) (sorbinil; 25 mg/kg/day p.o.) and the sorbinil treatment was associated with significant inhibition of polyol pathway intermediates in both lens and sciatic nerve. This suggests that polyol pathway activity in the lens may translate to oxidative stress-driving stimulation of NGF gene expression in the iris. The change is selective for NGF, because expression of the analogous neurotrophin, neurotrophin-3 (NT-3), was unaltered in the same irises. These changes suggest that oxidative stress and/or inflammation can drive up NGF expression in diabetes—a mechanism that might participate in iritis. 相似文献
10.
Seto JL Brewster CE Lombardo SJ Tibone JE 《The Journal of orthopaedic and sports physical therapy》1989,11(1):8-18
From the Kerlan-Jobe Orthopaedic Clinic, 501 E. Hardy Street, Suite 200, Inglewood, CA 90301. New information regarding the isometric placement of the anterior cruciate ligament (ACL) substitute, revascularization process, and biomechanical stresses have all contributed to and been incorporated in the rehabilitation program after ACL reconstruction. Treatment protocols specifically designed for the patient following ACL reconstruction are imperative to return the individual to his or her preinjury status. Care is taken to limit the amount of stress placed on the ligament substitute especially at end of range extension. A program incorporating techniques for developing range of motion and strength while still preserving stability at the knee joint is still of the utmost importance. This program is a revision of a previously reported regimen from this facility (Brewster, Moynes, Jobe, J Orthop Sports Phys Ther 5:121-126, 1983) and is based upon clinical experience and research information. J Orthop Sports Phys Ther 1989;11(1):8-18. 相似文献