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991.
This paper reviews the evolution of U.S. policy toward medical technology in areas such as cost containment, regulation of devices and drugs, and third party reimbursement. In addition the authors chronicle the diffusion of major medical technologies, procedures, and organizational innovations in the United States. Finally, the article provides tentative observations on the effect of recent policy changes and concludes with some recommendations for the future.  相似文献   
992.
This article describes and explains the impact of the National Health Service bureaucracy on the diffusion of medical technology in the United Kingdom. Through case studies of six medical technologies, the author demonstrates how health care authorities may exercise control by using the central financing system to dampen the general diffusion of technology. However, the United Kingdom has less control in specific cases due to the absence of a bureaucratic body to coordinate the evaluation and introduction of new technology.  相似文献   
993.
The qualities of daughter versus same-sex friend relationships were described by 151 married and widowed elderly women. The relation of these qualities to life satisfaction was assessed. Relationship qualities predicted life satisfaction in widowed women but not in married women. Significant predictors of life satisfaction for widows included the emotional support of daughters, the instrumental support of friends and friendship strength. In a comparison of the relationship qualities, both married and widowed respondents described daughters as providing more stimulation, ego support and utility than friends. Respondents also reported that relationships with daughters were stronger than those with friends. Married women described relationships with both daughters and friends as more stimulating than widowed women. The value of assessing qualitative indices compared to quantitative indices of later life relationships is discussed.  相似文献   
994.
Infantile glaucoma in Down's syndrome (trisomy 21)   总被引:2,自引:0,他引:2  
We examined five patients with Down's syndrome and bilateral infantile glaucoma. In the first few months of life four patients had large cloudy corneas, breaks in Descemet's membrane, increased intraocular pressure, photophobia, and tearing. In one patient the diagnosis was delayed until 3 1/2 years of age because of concomitant nasolacrimal duct obstruction. Two patients developed cataracts and retinal detachment and have undergone multiple surgical procedures. The clinical course in these two older patients suggests that coexistence of congenital glaucoma, severe myopia, and cataracts in patients with trisomy 21 strongly predisposes for the development of retinal detachment and poor visual outcome.  相似文献   
995.
996.
A retrospective cohort study of 863 pregnancies cared for by family physicians at three sites--rural-rural (RR), rural-urban (RU), and urban-urban (UU)--was designed to test the hypothesis that ready on-site access to perinatal subspecialists would improve pregnancy outcome. No differences in delivery type, length of gestation, birth weight, or nursery care were found. An Apgar score of less than 7 at 1 minute or less than 8 at 5 minutes was 2.17 and 2.31 times more likely at RU and 2.48 and 2.60 times more likely at UU, respectively, than at RR. The overall Cesarean section rate was 9.6 percent, forceps rate was 7.2 percent, and nonroutine nursery care rate was 7.9 percent. Neonatal and perinatal mortality rates were 3.5 and 4.6 per 1,000 live births. There is no evidence that on-site perinatal subspecialists improve perinatal outcome when care is provided by board-certified family physicians. Small obstetric centers provide quality perinatal care with outcome dependent on physician's skill rather than on technology.  相似文献   
997.
A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.  相似文献   
998.
Intestinal thermophilic Campylobacter species produce stable patterns when subjected to bacterial restriction endonuclease DNA analysis (BRENDA); this technique is therefore of considerable value in epidemiological studies. BRENDA was used to examine thermophilic Campylobacter species from humans, wild and domestic animals. One hundred and ninety-four (61%) of 316 isolates of Campylobacter jejuni from humans had BRENDA patterns which could be matched to those of animal isolates. Poultry appear to be a major source of infection for C. jejuni in humans with nearly half (49.7%) of the human isolates giving patterns which were indistinguishable from those isolated from poultry. A total of 60 BRENDA types were identified from 316 human isolates and 11 of these had the same pattern as those isolated from poultry. One of the three Campylobacter coli BRENDA types recovered from poultry was indistinguishable from a human isolate type. Pigs appear to be only a minor source of C. coli infection for humans in New Zealand. Rats were found to be infected with strains of C. jejuni with BRENDA patterns indistinguishable from those infecting humans, poultry and a horse. None of the 102 isolates of Campylobacter species from wild birds gave BRENDA patterns similar to those of isolates from humans.  相似文献   
999.
Test meals with 10.9 g dietary fibre from sugar beet and corresponding control meals were given to eight healthy subjects, aged 67 ± 9 years. The postprandial glucose, triglyceride, hormone and glycerol responses were monitored during 3 hours. After the beet fibre meal the insulin and C-peptide areas were reduced by 28 ( P < 0.01) and 22% ( P > 0.025), respectively, and the somatostatin levels increased by approximately 30% ( P > 0.05). Further, the maximum relative postprandial reduction of plasma glycerol levels was less evident after the fibre-rich meal than after the control meal (36 ± 4% v. 46 ± 4%, P < 0.05). There was no apparent difference in the overall glycaemic response between the meals. The triglyceride levels were similar after both test meals.
Suspension of beet fibre bread given to rats by oro-gastric intubation induced lower blood glucose response than a control bread at 15 and 30 min ( P < 0.001), respectively, but a similar insulin response.
The results suggest an effect of beet fibre on the rate of carbohydrate absorption, expressed as a lower insulin response in the healthy volunteers and a reduced glucose response in the rat.
The mechanism behind this effect in healthy subjects could possibly be mediated by an increased somatostatin response.  相似文献   
1000.
Morphology of hybrids between Aedes (Protomacleaya) zoosophus and Ae. (Pro.) triseriatus group species is described. Adult females of hybrids key to Ae. zoosophus. Hybrids are differentiated from Ae. zoosophus by the dark longitudinal medial or submedial lines on the thorax and by the reduced width of the light tarsal and abdominal bands. The transverse band of light scales on the anterior scutum is complete in Ae. hendersoni/Ae. zoosophus hybrids and incomplete in Ae. triseriatus/Ae. zoosophus hybrids. Aedes brelandi/Ae. zoosophus hybrids are similar to Ae. hendersoni/Ae. zoosophus hybrids. However, due to the allopatric distributions of Ae. brelandi and Ae. zoosophus, such hybrids are not expected.  相似文献   
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