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111.
112.
Everyone should know his or her cholesterol level. The means are now available for lowering cholesterol in the general population. Such efforts should be coupled with identification of moderate- and high-risk individuals for whom special efforts should be made in cholesterol lowering. The dietary approach outlined by the American Heart Association, which is clearly described in The Living Heart Diet (6), provides the best overall strategy for reducing cholesterol and for battling the epidemic of cardiovascular deaths that represents the No. 1 health problem in our society.  相似文献   
113.
Regional anaesthesia and surgical morbidity   总被引:4,自引:0,他引:4  
This review assesses the results of studies examining the influence of regional anaesthesia on surgical morbidity. Morbidity appears to be reduced when procedures below the umbilicus are concerned, but evidence is less convincing for upper abdominal and thoracic procedures.  相似文献   
114.
The evolution of a collagen/vicryl composite membrane designed as a prosthetic material for use in urinary tract surgery is described. The early experiments in which collagen film alone was used to repair experimental ureterotomies are reviewed together with our first experiments with the collagen/vicryl prosthesis in the repair of partial nephrectomies and of full thickness defects created in the urinary bladder of experimental rabbits. These early results led to the preparation of a composite using a more highly purified collagen and employing a method of sterilisation (gamma irradiation) which would be acceptable for regular use in medical products. The results of a further series of partial nephrectomy and full thickness bladder repairs show that irradiation does not compromise the efficacy of the collagen/vicryl composite in vivo.  相似文献   
115.
116.
Pulse-generated runoff: a new method of determining calf vessel patency   总被引:2,自引:0,他引:2  
A non-invasive method of determining calf vessel patency before femorodistal bypass has been developed. This pulse-generated runoff (PGR) system generates blood flow in patent calf arteries by means of a pulsatile cuff even if the existing Doppler signal is inaudible. PGR was compared with pre-operative arteriography in 95 ischaemic limbs and both were compared with the peripheral resistance measured at operation in 62 limbs. There was a highly significant correlation between the PGR and arteriogram scores (rs = 0.74, P less than 0.001) but PGR tended to detect more patent vessels than arteriography. The peripheral resistance correlated better with PGR than arteriography (rs = -0.71 and -0.54 respectively, P less than 0.001). PGR is a simple, non-invasive method of determining calf and foot vessel patency pre-operatively.  相似文献   
117.
Phorbol esters are hypothesised to produce a protein kinase C (PKC)-dependent increase in the probability of transmitter release via two mechanisms: facilitation of vesicle fusion or increases in synaptic vesicle number and replenishment. We used a combination of electrophysiology and computer simulation to distinguish these possibilities. We constructed a stochastic model of the presynaptic contacts between a pair of hippocampal pyramidal cells that used biologically realistic processes and was constrained by electrophysiological data. The model reproduced faithfully several forms of short-term synaptic plasticity, including short-term synaptic depression (STD), and allowed us to manipulate several experimentally inaccessible processes. Simulation of an increase in the size of the readily releasable vesicle pool and the time of vesicle replenishment decreased STD, whereas simulation of a facilitation of vesicle fusion downstream of Ca2+ influx enhanced STD. Because activation of protein kinase C with phorbol ester enhanced STD of EPSCs in rat hippocampal slice cultures, we conclude that an increase in the sensitivity of the release process for Ca2+ underlies the potentiation of neurotransmitter release by PKC.  相似文献   
118.
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation.  相似文献   
119.
Abstract: Background : A woman chooses to breastfeed for many reasons. Recent research, however, suggests that parental attitudes toward breastfeeding are stronger predictors of infant feeding choice than commonly cited sociodemographic factors. The objective of the current study was to compare the infant feeding attitudes of expectant couples, and to determine to what degree their individual attitudes during early pregnancy were predictive of the method of infant feeding at discharge from hospital. Methods : A convenience sample of pregnant women (gestational age 8–12 weeks), who were attending maternity clinics in Glasgow, Scotland, in 2000, completed the 17‐item Iowa Infant Feeding Attitude Scale (IIFAS), together with their partners. Results : The IIFAS was completed by 108 expectant couples. At discharge from hospital 49.1 percent of women were exclusively breastfeeding, and 50.9 percent were exclusively formula‐feeding. A woman's total infant feeding attitude score was significantly correlated with her partner's score(r = 0.67, p < 0.001). There was no difference in the infant feeding attitudes of formula‐feeding couples(p = 0.987), but breastfeeding women tended to be more supportive of breastfeeding than their partners(p = 0.022). Maternal, but not paternal, infant feeding attitude was a significant predictor of the choice of feeding method (OR = 1.16 95% CI = 1.09–1.24). Conclusions : Infant feeding attitudes tended to be shared by expectant couples. Maternal infant feeding attitude was a better predictor of feeding choice than were demographic factors. Paternal attitudes were not found to be independently associated with feeding choice. Identification of women with neutral infant feeding attitudes using the IIFAS may be an effective way of targeting interventions at those women who are most likely to be receptive to such programs.  相似文献   
120.
A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution.  相似文献   
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