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41.
L. Lima V. Arce M. J. Diaz J. A. F. Tresguerres J. Devesa 《Clinical endocrinology》1991,35(2):129-135
OBJECTIVE: The aim of this study was to investigate the effect of a single dose of clonidine on the pattern of GH release in response to a 10-hour continuous GRF infusion in normal man. DESIGN: Plasma GH was analysed in samples withdrawn at 20-minute intervals, from 0900 to 1900 h, according to the following protocols: in a control study, a placebo was given at 1000 h; in other experiments, clonidine (300 micrograms, orally) was given at 1000 h, alone or together with a continuous intravenous infusion of GRF 1-29 (0.3 micrograms/kg/h) starting at this time. In another experiment, the continuous infusion of GRF 1-29 was preceded by placebo administration at 1000 h. PATIENTS: Eight normal volunteers (four women and four men), aged 19-24 years were studied. MEASUREMENTS: Plasma GH levels were measured by RIA. Analysis of the pattern of GH secretion was performed using cluster analysis. RESULTS: Clonidine induced a slight but significant increase in plasma GH values, peaking 60 to 120 minutes later; however, no significant changes were observed in indices of total and pulsatile GH release for the whole sampling period in this study. Continuous GRF administration led to increased episodic GH secretion, by augmenting GH peak amplitude, although peak frequency was not modified. An increase in interpulse GH values was also observed during GRF infusion. Pretreatment with clonidine clearly changed the pattern of GH release during GRF infusion: the amount of GH secreted was significantly higher, the number of GH peaks significantly increased, and almost all the GH was secreted within them. CONCLUSIONS: These data concord with our previous demonstration that clonidine disrupts the hypothalamic-somatotroph rhythm by inhibiting the hypothalamic release of somatostatin. Given that clonidine pretreatment induced a more physiological episodic pattern of GRF-induced GH release, the possibility of combining clonidine and GRF therapy for short stature in children is envisaged. 相似文献
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A rare case of a patient with Laurence-Moon-Biedl syndrome associated with hypothalamic hamartoma is described. The English-language literature contains no cases of patients with this association. The clinical manifestations of this syndrome, those of hypothalamic hamartomas, and the appearance of the tumors on magnetic resonance images are discussed. 相似文献
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E. Andrs G. Kaltenbach E. Noel M. Noblet‐Dick A.‐E. Perrin T. Vogel J.‐L. Schlienger M. Berthel J. F. Blickl 《International journal of laboratory hematology》2003,25(3):161-166
Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia. 相似文献
46.
L R Delgado F Nieto A G Diaz R Schwarcz 《International journal of gynaecology and obstetrics》1991,36(4):271-276
The relationship between maternal age and cesarean section in low-risk nulliparas was analysed in 7454 perinatal clinical records selected from eleven databases of Latin American institutions obtained with a comprehensive perinatal information system. The risk of cesarean section in nulliparas between 29 and 49 years of age was found to be three times higher than that corresponding to pregnant women of lesser age. This clearly more aggressive obstetrical conduct could not be explained by the main indications for cesarean section. 相似文献
47.
The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short‐ and long‐term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post‐surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important. 相似文献
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R. Kazi V. Prasad R. Venkitaraman C.M. Nutting P. Clarke P. Rhys‐Evans K.J. Harrington 《Clinical otolaryngology》2006,31(6):525-530
Objective: To determine the effects of a total laryngectomy on the swallow and subsequent quality of life in head and neck cancer patients. Design: Cross‐sectional single centre cohort study. Setting: Head and Neck Oncology Unit, Tertiary Referral Unit. Patients: Sixty‐two patients who underwent total laryngectomy at our centre participated in the study. Methods: Subjects were stratified by age, sex, tumour stage, other procedures such as myotomy and nerve re‐implantation. Pharyngectomy, glossectomy, flap reconstruction, neck dissection and previous radio‐ and chemotherapy were also assessed to see if they affected swallow and subsequent quality of life. Main outcome was measured using the MD Anderson Dysphagia Inventory questionnaire. Results: Responses were received from 46 males and 16 females (response rate of 80.5%) with a mean age of 64.7 years (SD 9.4). Median follow‐up in patients was 90 months (range 1–276). The mean MD Anderson Dysphagia Inventory total score in our series of patients was 77.7 (SD 16.6). MD Anderson Dysphagia Inventory global score was 79.4 (SD 22.6), Emotional score was 77.7 (SD 17.8), Functional score 81.3 (SD 15.9) and Physical score was 74.1(SD 18). Statistically significant differences were seen between the emotional scores of glossectomised and non‐glossectomised patients (Mann Whitney, P = 0.04). No significant correlation was seen between the subscale scores and the remaining treatment variables such as age, gender, site, tumour stage, myotomy, nerve implantation, radiotherapy, reconstruction and major complications. Conclusion: This questionnaire study is the largest of its type to assess the swallow of patients who have undergone laryngectomy at a single centre. The overall result confirmed that most patients had a subjectively good swallow. Only glossectomy and the method of PE segment closure were shown to significantly affect swallowing outcomes following surgery. We recommend further work especially prospective studies pre and post surgery using this or similarly validated instruments to fully assess swallow in the laryngectomy population. 相似文献