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41.
In a double-blind placebo-controlled cross-over study, 30 patients with Delayed Sleep Phase Syndrome (DSPS) were included, of whom 25 finished the study. Melatonin 5 mg was administered during two weeks in a double-blind setting and two weeks in an open setting successively or interrupted by two weeks of placebo. The study's impact was assessed by measurements of the 24-h curves of endogenous melatonin production and rectal temperature (n=14), polysomnography (n=22), actigraphy (n=13), sleep log (n=22), and subjective sleep quality (n=25). Mean dim light melatonin onset (DLMO) (±SD), before treatment, occurred at 23.17 hours (±138 min). Melatonin was administered five hours before the individual DLMO. After treatment, the onset of the nocturnal melatonin profile was significantly advanced by approximately 1.5 hour. Body temperature trough did not advance significantly. During melatonin use, actigraphy showed a significant advance of sleep onset and polysomnography, a significant decreased sleep latency. Sleep architecture was not influenced. During melatonin treatment patients felt significantly more refreshed in the morning. These results show that analysis of DLMO of patients suffering from DSPS is important both for diagnosis and therapy. These results are discussed in terms of the biochemistry of the pineal.  相似文献   
42.
We tested the hypothesis that pharmacological reduction of the increase in cardiac output during dynamic exercise with a large muscle mass would influence the cerebral blood velocity/perfusion. We studied the relationship between changes in cerebral blood velocity (transcranial Doppler), rectus femoris blood oxygenation (near-infrared spectroscopy) and systemic blood flow (cardiac output from model flow analysis of the arterial pressure wave) as induced by dynamic exercise of large (cycling) vs. small muscle groups (rhythmic handgrip) before and after cardioselective β1 adrenergic blockade (0.15 mg kg?1 metoprolol i.v.). During rhythmic handgrip, the increments in systemic haemodynamic variables as in middle cerebral artery mean blood velocity were not influenced significantly by metoprolol. In contrast, during cycling (e.g. 113 W), metoprolol reduced the increase in cardiac output (222 ± 13 vs. 260 ± 16%), heart rate (114 ± 3 vs. 135 ± 7 beats min?1) and mean arterial pressure (103 ± 3 vs.112 ± 4 mmHg), and the increase in cerebral artery mean blood velocity also became lower (from 59 ± 3 to 66 ± 3 vs. 60 ± 2 to 72 ± 3 cm s?1; P < 0.05). Likewise, during cycling with metoprolol, oxyhaemoglobin in the rectus femoris muscle became reduced (compared to rest; ?4.8 ± 1.8 vs. 1.2 ± 1.7 μmol L?1, P < 0.05). Neither during rhythmic handgrip nor during cycling was the arterial carbon dioxide tension affected significantly by metoprolol. The results suggest that as for the muscle blood flow, the cerebral circulation is also affected by a reduced cardiac output during exercise with a large muscle mass.  相似文献   
43.
A case of branched-chain keto aciduria is described. The boy's clinical picture was similar to that of patients with the intermittent form of this disorder, but severe mental retardation was present. It proved possible to treat him successfully with a diet low in branched-chain amino acids and, at the age of 3 years, after 18 months' treatment, his mental development corresponded with his age. Details are given of the clinical course and the dietary treatment. The findings in the patient's family are also described, with the results of oral loading tests with 1-leucine performed on all members of the family.  相似文献   
44.
ABSTRACT: Van Acker, K. J., Vanden Brande, J. and Holvoet, H. (Departments of Paediatrics and Pathology, State University, Gent, Belgium). Renal biopsy studies in 150 children with non-specific glomerulopathy. Acta Paediatr Scand, 63:345, 1974.–The experience with light microscopic examination of kidney biopsies in 150 children with nonspecific glomerulopathy is reported. Most major types of glomerular lesions, as they are at present known, were observed but in a very uneven distribution. Four groups of clinical symptoms were observed in the primary as well as in the associated non-specific glomerulopathies: hematuria, proteinuria, acute nephritic syndrome and nephrotic syndrome. Although in a number of instances, the histologic lesio.i was suggested by the clinical picture, a correlation was lacking in most instances. More information was obtained from the histology when the evolution was considered, particularly in the primary nephrotic syndrome and the Schonlein-Henoch nephropathy.  相似文献   
45.
Variability between observers and specificity of sinus radiographic findings are subject to discussion. The aim of this study was to assess interobserver variability, between four physicians, two otolaryngologists and two radiologists, in the evaluation of 100 maxillary sinus radiographs. Equal agreement was found within the specialities when rating radiographs as normal or abnormal (80%). Kappa values for interobserver agreement were 0.45 for otolaryngologists and 0.58 for radiologists, both representing fair to good agreement. Otolaryngologists reported more abnormalities (67 vs, 57). Agreement on specific findings (complete opacity, fluid level and mucosal swelling) was fair to good (kappa values between 0.38 and 0.83). Agreement between the four physicians was lower on all outcomes. It is concluded that interobserver variability is within acceptable limits and justifies the continued use of conventional sinus radiographs for confirmation of maxillary sinus disease.  相似文献   
46.
In a nationwide survey on oropharyngeal carcinoma in the Netherlands (1986–1990), 380 patients with a tonsillar carcinoma were retrospectively studied. The records of 268 (71%) men and 112 (29%) women with a median age of 59 yr (range 31–91), who had squamous cell carcinoma (272 patients, 98%) or undifferntiated carcinoma (8 patients, 2%) were reviewed with respect to treatment, disease-specific survival and locoregional control. Distribution by stage according to the UICC'92 system was: 27 patients (7%) stage, I, 59 (15%) statge II, 99 (26%) stage III, 182 (48%) stage IV and 13 patients (3%) unknown stage. Using a previously reported revised staging system the following distribution was obtained: 118 patients (31%) statge I, 120 (31%) stage II, 67 (18%) stage II, 54 (14%) stage IV and 21 patients (6%) with an unknown stage. Treatment consisted of radiotherapy alone in 231 patients (61%), surgery and radiotherapy in 101 (27%), surgery alone in 30 (8%), chemotherapy in 5(2%) and 13 patients (3%) did not receive any treatment. At 5-yr the overall survival was 32%, the disease-specific survival 42% and the locoregional control 61%. In patients treated with radiotherapy alone the disease-specific survival was 39%, for surgery and radiotherapy 53% and for surgery alone 83%. The disease-specific suvival according to UICC'92 stage was 71% in stage I, 59% in II, 50% in III and 32% in stage IV (P < 0.0001). In the revised staging the survival figures were 63% in stage I, 43% in II, 31% in III and 9% in IV (P < 0.0001). The two staging systems appeared to be comparable in prognostic discrimination; the clinical relevance of the revised stage might, however, be slightly superior to the UICC'92 version. The difference in results after radiotherapy alone and surgery + radiotherapy remained significant, also after adjusting for stage (P < 0.0001).  相似文献   
47.
Abstract: This report describes an infant with clinical features consistent with the yellow nail syndrome (YNS), a rare autosomal dominant disorder. He presented at birth with congenital lymphoedema and was referred at 6 months of age for investigation of recurrent cough and wheeze. He had clinical and radiological evidence of bilateral pleural effusions and a pericardial effusion. Following a lung biopsy and pericardial window these were shown to be manifestations of his lymphatic abnormality. He also had persisting middle ear effusions causing conductive deafness requiring hearing aids and secondary immunodeficiency requiring regular immunoglobulin infusions.  相似文献   
48.
ABSTRACT. Serum lipid abnormalities are common in familial hemophagocytic lymphohistocytosis (FHL), a disorder also characterized by fever, hepatosplenomegaly, pancytopenia and a prominent lymphohistiocytic accumulation in the mononuclear phagocyte system. The lipoprotein pattern in nine children with FHL was studied with a quantitative method measuring cholesterol and triglycerides in each major class of lipoproteins. Triglycerides were markedly elevated during active FHL in serum, very low density lipoproteins, and low density lipoproteins. Cholesterol was increased in very low density lipoproteins whereas both triglycerides and cholesterol were extremely low in high density lipoproteins. These lipoprotein abnormalities, reversible on successful therapy, are compatible with a depressed lipolytic activity. Post-heparin levels of lipoprotein lipase and hepatic lipase in plasma were studied in four children and found to be markedly low during active FHL. We suggest that inflammatory cytokines, which may strongly suppress lipoprotein lipase activity, can be important mediators in the pathophysiology of FHL and that they may participate in the development of the lipid abnormalities.  相似文献   
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