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31.
This study reports our experience with low-dose prostaglandin E1 (PGE1) treatment of 91 newborns with ductus dependent congenital heart disease (CHD). PGE1 efficacy, side-effects as well as the cardiovascular and respiratory profile of the patients were analysed. PGE1 doses > 0.02 g/kg per minute were used for only 5.3% of the total 23 656 h of treatment. The mean systolic blood pressures did not differ from the normal mean for patients with cyanotic CHD, while the diastolic values were lowered. Respiratory support was required only during 13.7% of the total treatment time. Apnoeas occurred in 21 (38%) of the 55 spontaneously breathing infants, who all had a cyanotic CHD. The incidence of apnoeas was lower during treatment with doses < 0.01 g/kg per minute.  相似文献   
32.
Intracortical excitability in amyotrophic lateral sclerosis (ALS) is impaired. The effectiveness of the glutamate antagonist riluzole (Rilutek, Rh?ne-Poulenc Rorer) in ALS has been shown in clinical studies. In healthy subjects it modifies intracortical excitability in a frequently used double-stimulus paradigm of transcranial magnetic stimulation (TMS). Under riluzole intracortical inhibition is enhanced in healthy individuals, although not always significantly, whereas intracortical facilitation has been described as reduced [10, 11]. We wanted to find out whether riluzole affects and potentially rebalances impaired intracortical excitability in ALS. We, therefore, enrolled 13 patients with clinically and electromyographically confirmed ALS into this study. Five patients had to be excluded because motor thresholds were too high to get reliable motor evoked potentials (MEPs). In the remaining 8 patients, mean age was 59.9 +/- 11.9 years (+/- standard deviation) and mean symptom duration 9.6 +/- 2.5 months. Intracortical excitability was assessed before and 1.5 hours after the first intake of a loading dose of 100 mg of riluzole using a conventional paired-pulse TMS paradigm with interstimulus intervals (ISI) ranging from 1-30 ms and intensities adjusted to yield MEPs of 1.0 mV for test pulses and of 90% active motor threshold for conditioning pulses. Patients' baseline results were compared to those of 9 age-matched, healthy control subjects. Before drug intake, motor thresholds did not differ between groups, but there was significantly less intracortical inhibition in the ALS patient group. Riluzole intake did not significantly alter motor thresholds or intracortical excitability in the ALS patients. We conclude that riluzole does not immediately influence intracortical excitability in ALS. Our results are in contrast to the findings of Stefan et al (1998) [14] where a partial normalization of intracortical inhibition in ALS was observed after at least 5 days of drug intake. The difference between that study and our result may indicate a delayed onset of riluzole's influence on intracortical excitability.  相似文献   
33.
The Baltimore Eye Survey identified race, intraocular pressure, systemic hypertension, perfusion pressure, family history, and quite possibly the structure and organization of the optic nerve head as potential etiologically significant risk factors in the development of glaucomatous optic nerve damage. These findings have been confirmed by subsequent, sometimes equally rigorous population-based studies in other communities and countries. The Baltimore Eye Survey failed to demonstrate a role for diabetes but revealed that estimates of the significance of diabetes, like that of family history, are subject to considerable selection bias.  相似文献   
34.
Summary Blood (3.4–13.5% of blood volume) was pumped in and out of the circulation of rats at different rates and period lengths during continuous measurements of blood conductivity (reciprocally related to hematocrit) and arterial pressure. Hct followed the same zig-zag course as the induced changes of blood volume in every case, indicating that fluid shifts (v) between interstitium and intravascular space closely follow blood volume changes. As the het increase during reinfusion was not as great as the preceding decrease, hct dropped continuously during the 20–90 minutes of experimentation, so that a final volume increase (v) by about 4% was calculated, which was confirmed by a corresponding decrease of plasma protein concentration. Both final v and v during periodic volume change (% B.V.) were greater when arterial pressure dropped. v was directly related to % B.V. but not to its rate of change. Heart rate dropped slightly at the end of the reinfusion periods, whereas it rose to control at the end of the withdrawal periods. The results were regarded as evidence of blood volume regulation proportional to the absolute volume of blood lost in non-hypotensive hemorrhage.Supported by DFG-grant AZ 3/3  相似文献   
35.
Summary Isolated rat pineal glands were incubated in vitro and the release of endogenous noradrenaline or 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) was determined by HPLC with electrochemical detection. In the absence of test drugs, the spontaneous outflow of noradrenaline was about 10 fmol/10 min and electrical stimulation (5 Hz, 1500 pulses) evoked the release of about 70 fmol noradrenaline. Nomifensine enhanced the spontaneous outflow of noradrenaline about threefold and the electrically evoked release of noradrenaline about sixfold. In the presence of nomifensine, the 2-adrenoceptor antagonist yohimbine markedly increased the electrically evoked release of noradrenaline, whereas the 1-adrenoceptor antagonist prazosin had no effect. Clonidine inhibited the electrically evoked release of noradrenaline by about 65%, and this was antagonized by yohimbine in a competitive manner. In the absence of drugs, the initial spontaneous outflow of 5-HT was (compared with noradrenaline) very high 64 mol/10 min. It declined by 80% within 1 h of incubation in vitro. The outflow of 5-HIAA amounted initially to 38 mol/10 min and declined by 40% within 1 h of incubation. Addition of l-tryptophan (10 mol/1) after 1 h of incubation in vitro largely enhanced the outflow of 5-HT and 5-HIAA within 30 min of incubation (about ten- and fourfold, respectively). When l-tryptophan was present from the onset of incubation the initial outflow of 5-HT and 5-HIAA was only slightly elevated, but the decline was largely attenuated. Neither omission of calcium nor addition of nomifensine, clonidine or yohimbine significantly affected the spontaneous outflow of 5-HT or 5-HIAA. Likewise, neither electrical stimulation in the absence or presence of nomifensine and yohimbine nor stimulation by high potassium (45 mmol/1) significantly affected the outflow of 5-HT or 5-HIAA.In conclusion, the release of endogenous noradrenaline from the sympathetic nerves terminating in the pin eal gland is inhibited by presynaptic 2-adrenoceptors. The outflow of 5-HT from the pineal gland originates almost exclusively from non-neuronal cells, most probably the pinealocytes, and depends largely on a continuous de novo synthesis. Catabolism of 5-HT to 5-HIAA in the pineal gland occurs mainly in an extraneuronal compartment, probably the pinealocytes and/or the interstitial cells of the pineal gland. Send offprint requests to K. Racké at the above address  相似文献   
36.
R. A. Blakelock was a highly acclaimed 19th Century visionary American painter who spent 25 years in mental hospitals. Students rated random samples of Blakelock's work completed before, during, and after his breakdown. Paintings completed after the start of his long-term hospitalization were rated lower in skill and higher in psychopathology than those done before his breakdown. The difference in perceived psychopathology persists when ratings for skill level are controlled. There were also differences due to training level of raters and whether or not the paintings were presented in color.  相似文献   
37.
38.
BACKGROUND: The impact of various medical and demographic factors on the quality of life (QoL) of breast cancer patients has been discussed controversially. We investigated the influence of six different factors on long-term QoL and body image of women with primary breast cancer. PATIENTS AND METHODS: Two-hundred and seventy-four breast cancer patients were administered the QoL questionnaire following a mean interval of 4.2 years after primary diagnosis. All women had been primarily treated for stage I to III breast cancer without evidence of distant metastases. QoL was evaluated by using the QLQ-C30 questionnaire Version 2.0. Supplementary scales included body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence. We analyzed the impact of tumor stage, surgical treatment, adjuvant radiotherapy, adjuvant cytotoxic therapy, age and length of follow-up period on the examined outcome parameters. RESULTS: At the time of the follow-up examination, patients showed minor impairment of QoL (mean 67.8) and body image (mean 24.8), but more fear of recurrence (mean 60.7). None of the studied factors had a significant impact on overall QoL (P >0.05) according to the QLQ-C30 questionnaire. In contrast, with the exception of the factors 'cytotoxic therapy' and 'radiotherapy' all investigated variables influenced at least one of the additional psychological scales (P <0.05). The primary surgical treatment modality had the strongest impact and affected all four scales. Patients treated with breast conservation reported a more favorable body image, compared to those treated with mastectomy (17.2 versus 37.5, P <0.01), more satisfaction with surgical treatment (4.0 versus 10.7, P = 0.01), rated a better cosmetic result (75.5 versus 57.1, P <0.01), but presented more fear of recurrence (63.9 versus 55.3, P = 0.04). CONCLUSION: Current QoL questionnaires do not sufficiently cover all relevant aspects of QoL, but might be complemented by breast cancer specific aspects such as body image and fear.  相似文献   
39.
Night blindness due to vitamin A deficiency is common during pregnancy among women in Nepal. The authors assessed the risk of maternal death during and after a pregnancy with night blindness among women participating in a cluster-randomized, placebo-controlled vitamin A and beta-carotene supplementation trial in Nepal from July 1994 to September 1997. Subjects were 877 women with night blindness and 9,545 women without night blindness during pregnancy. Women were followed from the time they declared that they were pregnant through the end of the study, representing a median follow-up of 90 weeks (interquartile range: 64-121 weeks). Mortality of night-blind women in the placebo group was 3,601 per 100,000 pregnancies. In comparison, the relative risk of dying among nonnight-blind women in the placebo group was 0.26 (95% confidence interval (CI): 0.13, 0.55), and the relative risk among women with or without night blindness in the vitamin A/beta-carotene group was 0.32 (95% CI: 0.10, 0.91) and 0.18 (95% CI: 0.09, 0.36), respectively. Night-blind women were five times (95% CI: 2.20, 10.58) more likely to die from infections than were women who were not night blind. These findings show that night blindness during pregnancy is a risk factor of both short- and long-term mortality among women. Vitamin A/beta-carotene supplementation ameliorates this risk to a large extent.  相似文献   
40.
O Kosoko  A Sommer  C Auer 《Ophthalmology》1986,93(7):882-886
Eighty eyes were tested using the computer-driven, automated threshold-related, three-level screening strategy of the Humphrey Field Analyzer. Using Goldmann perimetry as the standard, different statistical algorithms were used in an attempt to differentiate eyes with glaucoma (n = 24) from normal controls (n = 56). Seventeen or more absolute and/or relative defects anywhere in the full field test area identified approximately 95% of the glaucoma eyes and screened out 80% of the control eyes. Retesting these criteria on a second group of 25 glaucomatous and 108 control eyes provided comparable results. The number of stimulus presentations can be substantially reduced, without deterioration in either sensitivity or specificity, by using a two-level strategy and limiting testing to the nasal field.  相似文献   
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