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991.
A case of a giant aneurysm arising from the anterior cerebral artery and producing a left homonymous hemianopsia is presented. The aneurysm caused lateral compression of the posterior part of the optic chiasm. After preoperative dynamic assessment of the circle of Willis by angiography and by electroencephalographic recording during carotid artery compression, the aneurysm was trapped with microclips on the anterior cerebral artery proximal and distal to it. Visual field examination 6 months postoperatively showed complete visual field recovery. This is the first case of homonymous hemianopsia caused by an angiographically proven giant aneurysm of the ACA.  相似文献   
992.
The electrophysiologic effects of the beta-1 selective beta adrenergic blocking drug Betaxolol were investigated after intravenous (0.15 mg/kg body weight) and oral (20 mg/day) administration in 11 patients with atrioventricular-nodal reentrant tachycardia. Betaxolol significantly (p less than 0.01) prolonged cycle length, sinus node recovery time, AH-interval, as well as the antegrade functional refractory period of the slow and fast AV-nodal pathway. The effective refractory period of the fast AV-nodal pathway was also markedly increased (p less than 0.05). In only six patients could the effective refractory period of the slow AV-nodal pathway be determined; in the other patients, it was shorter than the effective refractory period of the atrium. The effective refractory period of the atrium and the ventricle was not significantly altered by Betaxolol. Intravenous administration of Betaxolol suppressed induction of tachycardia in eight patients, whereas after oral Betaxolol, tachycardia was not inducible in ten patients. Betaxolol prevented induction of tachycardia in two patients by prolonging antegrade conduction over the slow AV-nodal pathway. The retrograde fast AV-nodal pathway was blocked in eight patients. Presumably the increased effectiveness of oral Betaxolol can be attributed to higher Betaxolol plasma concentrations, reached after oral treatment (58 +/- 38 ng/ml), as compared to intravenous administration (40 +/- 40 ng/ml). There were no false positive results after intravenous testing of Betaxolol.  相似文献   
993.
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   
994.
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   
995.
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   
996.
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   
997.
998.
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   
999.
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   
1000.
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   
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