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51.
52.
Eleven patients between the ages of 6 and 18 years who had been treated for acute leukemia were investigated for growth and growth hormone (GH) secretion. All had undergone bone marrow transplantation (BMT) between 0.7 and 5.1 (median 2.0) years previously. Preparation of patients for BMT had included high-dose cyclophosphamide and total body irradiation. In the eight patients at risk of growth failure, the relative height decreased 0.5-2.5 SD units (median 1.0) during the follow-up period. Eight patients secreted subnormal amounts of GH as studied by measuring spontaneous pulsatile GH secretion overnight. The maximal nocturnal GH peak varied between 3.3 and 28.3 micrograms/l (median 9.3). The mean nocturnal GH concentration varied from 1.2 to 8.3 micrograms/l (median 2.3) and depended on the length of the follow-up period. We conclude that deficient GH secretion is one reason for poor growth after BMT. A good growth response to GH substitution would support the role of GH deficiency in the observed growth retardation after BMT.  相似文献   
53.
The modulatory role of protein kinase C (PK-C)- and Gi-protein-mediated signal transduction systems was studied in the cyclic variation of follicle-stimulating hormone (FSH)-stimulated cAMP production of rat seminiferous tubules. FSH (Metrodin, Serono, 30 mg/1) stimulated cAMP production 10-fold (p < 0.01) in a 3 h incubation of 5 mm segments of seminiferous tubules of stages II–VI of the epithelial cycle, but only 2-fold (p < 0.01) in stages VII–VIII. The PK-C activator 12-O-tetradecanoylphorbol 13-acetate (TPA, 100 nmol/1) suppressed the FSH effect on cAMP output by 50–70% (p < 0.01) in stages II–VI, but had no effect in stages VII–VIII. If the tubular segments were preincubated for 3 h in the presence of pertussis toxin (PT, 100 μg/1), the FSH-stimulated cAMP production of stages VII-VIII increased by 100–200% (p < 0.01), and now they also became responsive to the TPA suppression. Conversely, no effect of PT was observed in stages II–VI. Cholera toxin (CT, 100 μg/1) and forskolin (Fk, 100 μmol/1) nearly similarly stimulated the cAMP production in both stages studied (about 10-fold, p < 0.01), and TPA and PT potentiated the effects in a non-additive fashion. In conclusion, both Gi-protein and PK-C-mediated mechanisms modulate cAMP production of rat seminiferous tubules. A clear cyclic variation can only be demonstrated in FSH-stimulated cAMP production, but not if the Gs-protein or adenylate cyclase are directly stimulated. Upon FSH stimulation, the low cAMP production in stages VII–VIII is mainly due to the Gi-protein-mediated inhibition. In contrast, the absence (or non-function) of this inhibition mechanism explains the brisk cAMP response to FSH in stages II–VI. PK-C activation suppresses FSH-stimulated cAMP production only if it is not inhibited by the Gi-protein-mediated mechanism (stages II–VI), probably by inhibiting the FSH-receptor-Gs-protein association. It also increases CT and Fk-stimulated cAMP production, in this case inactivating the Gi-protein.  相似文献   
54.
Summary The prevalence of dysthymic disorder and and its relationship to social and health variables were investigated in a Finnish population aged 60 years or over. The prevalence was lower in men (17.2 per 100) than in women (22.9 per 100). In the total population the occurrence was higher in the widowed (24.9 per 100) than in the married (18.3 per 100). In men, dysthymic disorder was more common in those with a lower educational level (22.6 per 100) than with a higher educational level (15.1 per 100), and more common in persons receiving long-term institutional care or home nursing or home help (28.7 per 100) than in persons living independently at home (14.6 per 100). The rate was not related to age, marital status or occupation. In women, the occurrence was not related to age, marital status, education, occupation or form of social and health care. The female rate was higher than the male in the older group (70 yrs. +), in married persons, in those with a higher educational level and in those living independently at home. Underdiagnosing was evident. The occurrence of dysthymic disorder was related to poor health and poor functional status and to the occurrence of social and health stressors. No differences were found in the occurrence of the related factors between persons with dysthymic disorder and persons with major depression. Our results support the conclusion that the majority of cases of dysthymic disorders in the elderly are affective illnesses and not personality disorders.  相似文献   
55.

Purpose  

To evaluate the prevalence of anatomical variations in the circle of Willis predisposing to cerebral ischemia during intraoperative closure of a carotid artery.  相似文献   
56.
The aim of this study was to analyze the association between occurrence of enamel focal demineralization (EFD) lesions and caries on the smooth surfaces of permanent teeth and some parameters concerning dentofacial morphology in different age groups of Finnish children. Altogether 587 children aged 7, 9 and 12 years living in Helsinki and Kuopio, Finland were examined clinically and some parameters of dento-facial morphology were measured. Of the dento-facial morphological parameters, the size of the gonial angle seemed to be associated with caries indicators. The possible predictive value of dento-facial morphology for caries should be confirmed by longitudinal study.  相似文献   
57.
The modulatory role of protein kinase C (PK-C)- and Gi-protein-mediated signal transduction systems was studied in the cyclic variation of follicle-stimulating hormone (FSH)-stimulated cAMP production of rat seminiferous tubules. FSH (Metrodin, Serono, 30 mg/1) stimulated cAMP production 10-fold (p < 0.01) in a 3 h incubation of 5 mm segments of seminiferous tubules of stages II–VI of the epithelial cycle, but only 2-fold (p < 0.01) in stages VII–VIII. The PK-C activator 12-O-tetradecanoylphorbol 13-acetate (TPA, 100 nmol/1) suppressed the FSH effect on cAMP output by 50–70% (p < 0.01) in stages II–VI, but had no effect in stages VII–VIII. If the tubular segments were preincubated for 3 h in the presence of pertussis toxin (PT, 100 μg/1), the FSH-stimulated cAMP production of stages VII-VIII increased by 100–200% (p < 0.01), and now they also became responsive to the TPA suppression. Conversely, no effect of PT was observed in stages II–VI. Cholera toxin (CT, 100 μg/1) and forskolin (Fk, 100 μmol/1) nearly similarly stimulated the cAMP production in both stages studied (about 10-fold, p < 0.01), and TPA and PT potentiated the effects in a non-additive fashion. In conclusion, both Gi-protein and PK-C-mediated mechanisms modulate cAMP production of rat seminiferous tubules. A clear cyclic variation can only be demonstrated in FSH-stimulated cAMP production, but not if the Gs-protein or adenylate cyclase are directly stimulated. Upon FSH stimulation, the low cAMP production in stages VII–VIII is mainly due to the Gi-protein-mediated inhibition. In contrast, the absence (or non-function) of this inhibition mechanism explains the brisk cAMP response to FSH in stages II–VI. PK-C activation suppresses FSH-stimulated cAMP production only if it is not inhibited by the Gi-protein-mediated mechanism (stages II–VI), probably by inhibiting the FSH-receptor-Gs-protein association. It also increases CT and Fk-stimulated cAMP production, in this case inactivating the Gi-protein.  相似文献   
58.
Using electric and magnetic brain responses we tested whether violations of an abstract auditory regularity are processed in auditory cortex and whether abstract auditory regularities are retained for at least 10 s. The mismatch negativity (MMN) event-related potential and its magnetic counterpart (MMNm) were recorded to infrequent tone pairs of descending pitch (the second tone having a lower frequency than the first one) embedded in a sequence of tone pairs of ascending pitch, whereas the absolute frequency of both ascending and descending tone pairs varied on seven levels. Results showed that the dominant generators of the electromagnetic activity elicited by violations of the pitch-ascension rule lie within auditory cortex. We also found that the memory representation of pitch-ascension is retained for at least 10 s. When short trains of ascending-pitched tone pairs were followed by a silent period of 8-12 s, descending-pitched probe tone pairs elicited the MMN component when a single reminding pair with ascending pitch was presented before the probe. The reactivating effect of the reminder was similar to what has been previously shown for concrete auditory regularities, such as the constancy of tone pitch. The present results support the view that auditory cortical functions can process sensory and categorical information in a similar manner.  相似文献   
59.
60.
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