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81.
Objectives. To confirm the observation that has been occasionally reported in the literature that perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and to assess the reasons for this lower perinatal mortality rate.

Methods. Secondary‐analysis based on published data.

Results. This exercise demonstrates that the perinatal mortality rate was lower in ethnic Chinese than in ethnic whites. The birth weight distribution in ethnic Chinese was more favourable with reduced births at two extremes of the distribution, and the exposure to risk factors for perinatal death by their mothers was also lower.

Conclusion: Perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and the lower perinatal mortality rate in ethnic Chinese is probably caused by their favourable birth weight distribution and lower exposure to risk factors of perinatal death by their mothers.  相似文献   

82.
A retrospective study of all ileogastrostomy procedures (n=26) performed in 1993 by one surgeon (IGMC) was carried out to investigate the hypothesis that Helicobacter pylori may be implicated in certain severe cases of postoperation nausea and diarrhea. Ten of 26 persons (38.5%) displayed nausea and notable diarrhea (greater than or equal to ten bowel movements per day), seven of which warranted upper GI investigation. One hundred per cent (seven of seven) of these persons were found to possess H. pylori upon C-14 breath test. In four of six cases eradication therapy (1 g amoxicillin b.i.d./20 mg omeprazole b.i.d. for 2 weeks) corresponded with a resolution of severe nausea and diarrhea (one additional case involved omeprazole use only), suggesting that H. pylori should be considered as a possible cause of these symptoms post-ileogastrostomy. Additionally, in four of seven cases persons were re-tested (C-14 breath analysis) at least 1 month post-therapy and in this group three persons were found to be free of the organism. All three cases of notable diarrhea and nausea resolved with treatment, providing the strongest evidence for a possible association between infection and these symptoms.  相似文献   
83.
Public involvement in health care priority setting: an economic perspective   总被引:1,自引:1,他引:0  
Background  Public involvement in health care decision making and priority setting in the UK is being promoted by recent policy initiatives. In 1993, the British Medical Association called for public consultation where rationing of services was to be undertaken. The approach to priority setting advocated by many health economists is the maximization of quality adjusted life years (QALYs). Typically, for a particular health care programme, the QALY calculation takes account of four features: (1) the number of patients receiving the programme, (2) the survival gain, (3) the gain in quality of life and, (4) the probability of treatment success. Only one feature, that relating to quality of life, is based upon public preferences. If the QALY is to be used as a tool for health care resource allocation at a societal level then it should incorporate broader societal preferences.
Methods  This study used an interview-based survey of 91 members of the general public to explore whether the traditional QALY maximization model is a good predictor of public responses to health care priority setting choices.
Results and conclusions  Many respondents did not choose consistently in line with a QALY maximization objective and were most influenced by quality of life concerns. There was little support for health care programmes that provided a prognostic improvement but left patients in relatively poor states of health. The level of respondent engagement in the survey exercise was not sensitive to the provision of supporting clinical information.  相似文献   
84.
  • ? Emergency nurse practitioners (ENPs) formally developed in accident and emergency (A & E) departments as a direct response to waiting times for the walking wounded, the need to reduce junior doctors hours and changes in nursing practice.
  • ? ENPs existed informally for many years in minor injuries units and specialist ophthalmic departments.
  • ? This study aimed to examine whether or not the role of ENP could be applied to the specialist service of a paediatric casualty department.
  • ? The results showed that 3% of patients could be seen and treated to conclusion by a children's ENP, and some patients could have their care accelerated by a children's ENP.
  • ? The introduction of children's ENPs would have an impact on waiting times, junior doctors work-load and the quality of patient care.
  相似文献   
85.
Aprikalim is a potent, specific, and selective opener of ATP-sensitiveK+ (KATP) channels. By virtue of this pharmacological property,aprikalim affords cardioprotection in experimental models ofischemia/reperfusion injury, and, at higher doses, also causesperipheral or coronary vasodilatation. Direct-acting peripheralvasodilators can cause myocardial lesions, particularly in ratsand dogs. However, unexpectedly, aprikalim produced this effectalso in monkeys. Thus, the primary aim of this investigationwas to assess whether in monkeys these myocardial lesions werethe direct or indirect consequence of the vascular effects ofaprikalim. Cyno-mologus monkeys were given the ß-adrenoceptorantagonist nado-lol (2 mg/kg po, twice daily) for 4 consecutivedays. On the third and fourth day of the experiment, they receivedaprikalim (1 mg/kg po). In another series, two monkeys carryingtelemetry transmitters for blood pressure and heart rate measurementswere also given aprikalim or its vehicle. Finally, aprikalim(1 mg/kg po for 2 days) or its vehicle was administered to ratswhich were concurrently treated with the ß-adrenoceptorantagonist atenolol (5 mg/ kg sc) or its vehicle. In cynomologusmonkeys, aprikalim produced focal and multifocal myocardialnecrosis of minimal to moderate intensity in or near the papillarymuscles of the left ventricle. These effects were abrogatedby nadolol. Similarly, necrotic lesions were caused by aprikalimonly in those rats which had not been pretreated with atenolol.In monkeys, aprikalim produced a marked and long-lasting decreasein aortic blood pressure, accompanied by an even more prolongedtachycardia. These results demonstrate that aprikalim can producemyocardial necrosis not only in rats but also in monkeys. Toour knowledge, this is the first time that such adverse effectsare reported for a vasodilator in monkeys. More importantly,these effects were prevented by blocking cardiac ß-adrenoceptors.Thus, the myocardial lesions produced by aprikalim may be attributedto its profound and prolonged hemodynamic effects.  相似文献   
86.
Our aim was to examine the feasibility of a totally laparoscopic insertion of a bifurcated aortofemoral bypass graft in a canine model and to compare the surgical results with those in control animals undergoing standard grafting and laparoscopic-assisted bypass procedures. Using a six-port approach, we exposed and cross clamped the aorta, tunneled a bifurcated Dacron graft, and performed an end-to-end aortic anastomosis while maintaining pneumoperitoneum by means of CO2. Proximal anastomoses were performed with 4/0 double-ended continuous Prolene sutures and distal anastomoses were performed through standard groin incisions. Total operating and aortic cross-clamp times were measured as was the total blood loss for each procedure. Clinical outcome was also documented. Eight female laboratory-bred hounds underwent successful totally laparoscopic aortobifemoral bypass grafting, eight underwent open grafting, and eight underwent laparoscopic-assisted bypass. Mean operating time was 193 minutes in the animals undergoing totally laparoscopic insertion vs. 156 minutes in the open group and 180 minutes in the laparoscopic-assisted group. Aortic cross-clamping time was also significantly longer at 87 minutes vs. 43 minutes (p < 0.001)=" in=" the=" totally=" laparoscopic=" group,=" but=" blood=" loss=" was=" less.=" all=" eight=" laparotomy=" and=" laparoscopic-assisted=" dogs=" were=" still=" alive=" with=" no=" complications=" at=" 28=" days,=" whereas=" three=" of=" the=" eight=" in=" the=" totally=" laparoscopic=" group=" showed=" evidence=" of=" temporary=" paraplegia.=" this=" experimental=" study=" demonstrates=" that=" a=" totally=" laparoscopic=" approach=" can=" be=" used=" to=" insert=" a=" bifurcated=" aortofemoral=" bypass=" with=" a=" proximal=" end-to-end=" anastomosis=" but=" currently=" does=" not=" save=" time=" and=" may=" increase=" the=" risk=" of=" neurologic=">Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995.  相似文献   
87.
The effect of increasing end-tidal enflurane concentration onthe auditory evoked response was studied in six patients. Aftera standard induction, anaesthesia was maintained with 70 nitrousoxide in oxygen and the end-tidal enflurane concentration wasincreased gradually from 0 to 1 over a period of 30 min. Theaveraged auditory evoked response was derived from the electroencephalogramand measurements were made of the latencies and amplitudes ofwaves I, HI, V, Pa and Nb within the auditory evoked response.The latencies of all waves and the interpeak latencies I toV and HI to V showed significant linear increases and the amplitudesof Pa and Nb showed significant linear decreases with increasingend-tidal enflurane concentration. These results could not beexplained by changes in deep body temperature or end-tidal carbondioxide concentration. The study demonstrated a dose-relateddirect effect of enflurane on the brainstem and early corticalcomponents of the auditory evoked response.  相似文献   
88.
The success of vertical gastroplasty may be jeopardized by gastric leakage or ulceration due to failure of the technique. Reports of band erosion and staple-line leakage have led us to seek technical improvements to reduce technical failures. We describe a modification to the technique of band placement and a manoeuvre to aid the placement of staples when the TA90 staple gun is used.  相似文献   
89.
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification are presented.  相似文献   
90.
Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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