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71.
M Knoepfelmacher MJ Pradal RD Dio LR Salgado M Semer BL Wajchenberg B Liberman 《Canadian Metallurgical Quarterly》1997,137(2):162-166
OBJECTIVE: To assess the plasma levels and action of arginine vasopressin (AVP) in patients with Cushing's disease. There are many reports that patients with Addison's disease have increased AVP levels associated with hyponatraemia and hypoosmolality, but none on the dynamics of secretion of this neurohormone during osmolality-based stimulation in patients with chronic hypercortisolism. DESIGN AND SUBJECTS: The plasma AVP concentration and the urinary and plasma osmolality after a 7.5-h water deprivation test (WDT) were evaluated in 13 patients with Cushing's disease and 15 normal (control) individuals. In patients with Cushing's disease we also assessed the urinary osmolality in response to 10 micrograms i.v. desmopressin (DDAVP) administered at the end of the WDT. RESULTS: At the end of the WDT, urinary osmolality was significantly lower in patients with Cushing's disease (511.5 +/- 148.5 mOsm/l) than in the normal subjects (981.1 +/- 107.1 mOsm/l, P < 0.001), whereas plasma osmolality did not differ between the two groups. Consequently, the urine/plasma osmolality ratio (Uosm/Posm) was lower in patients with Cushing's disease than in normal individuals (1.8 +/- 0.5 compared with 3.4 +/- 0.4, P < 0.001). The AVP concentration also was greater (7.3 +/- 3.1 pmol/l) in those with Cushing's disease than in the controls (3.9 +/- 2.3 pmol/l, P < 0.005). After administration of DDAVP to the hypercortisolaemic patients, the urinary osmolality attained (718.0 +/- 200.0 mOsm/l) was still lower than that in the normal group at the end of WDT (P < 0.005). CONCLUSIONS: Patients with Cushing's disease presented higher AVP levels and smaller Uosm/Posm ratios than normal subjects. After DDAVP, the patients with Cushing's disease were unable to concentrate the urine adequately. These data suggest that the kidney shows resistance to the action of both endogenous and exogenous AVP in patients with Cushing's disease. 相似文献
72.
RD LeBoeuf 《Canadian Metallurgical Quarterly》1994,5(1):79-87
The technique of renal time ultrasound of the scrotum is described. The examination was performed in 50 patients and 15 normal males at the Sahinbey Hospital. Given the clinical diagnosis ultrasound proved reliable in almost all cases. In this study ultrasonography of the scrotum has been found to be the most useful method demonstrating testicular diseases. 相似文献
73.
The extent of adverse health effects of isocyanates when combined with other chemicals is not well documented. This study was conducted as a 2.5-year follow-up as well as to determine daily and weekly effects of exposure to isocyanates and organic solvents on pulmonary function. The concentrations of chemicals sampled were below the recommended exposure criteria. No daily or weekly reduction in the subjects' pulmonary function was observed. The isocyanate/solvent-exposed subjects showed significant long-term reduction in their forced vital capacity (P < 0.05) and expiratory volume in 1 second (P < 0.001). No such changes were observed in non-exposed subjects or in those exposed only to organic solvents. The proportion of subjects who developed respiratory symptoms in the isocyanate-exposed group was not significantly greater than that of the non-exposed group. The results of this study indicate that long-term exposure to isocyanates, even in very low concentrations, may contribute to impaired pulmonary function. 相似文献
74.
JP Hubble KL Busenbark S Wilkinson RD Penn K Lyons WC Koller 《Canadian Metallurgical Quarterly》1996,46(4):1150-1153
We examined the effects and safety of deep brain stimulation (DBS) as a treatment for essential tremor (ET). Ten ET patients with disabling medication-refractory tremor underwent stereotactic implantation of a DBS lead in the left Vim thalamic nucleus and completed a 6-month follow-up. The Clinical Tremor Rating Scale and disability assessments were performed at baseline, 1-, 3-, and 6-month follow-up. There were significant improvements in dressing, drinking, eating, bathing, and handwriting as reported by the subjects. Tremor severity, writing, pouring, and spiral and line drawing were significantly improved as rated by the examiner. Improvements persisted through the 6-month follow-up period. Although global disability significantly lessened in the group as a whole, one subject with hand-finger tremor accentuated by writing had no change in disability status. In this 6-month open-label study, DBS was effective and safe in reducing tremor and functional disability in ET. 相似文献
75.
76.
Pigmentation phenotypes of variant extension locus alleles result from point mutations that alter MSH receptor function 总被引:2,自引:0,他引:2
LS Robbins JH Nadeau KR Johnson MA Kelly L Roselli-Rehfuss E Baack KG Mountjoy RD Cone 《Canadian Metallurgical Quarterly》1993,72(6):827-834
Coat colors in the chestnut horse, the yellow Labrador retriever, the red fox, and one type of yellow mouse are due to recessive alleles at the extension locus. Similarly, dominant alleles at this locus are often responsible for dark coat colors in mammals, such as the melanic form of the leopard, Panthera pardus. We show here that the murine extension locus encodes the melanocyte-stimulating hormone (MSH) receptor. In mice, the recessive yellow allele (e) results from a frameshift that produces a prematurely terminated, nonfunctioning receptor. The sombre (Eso and Eso-3J) and tobacco darkening (Etob) alleles, which both have dominant melanizing effects, results from point mutations that produce hyperactive MSH receptors. The Eso-3J receptor is constitutively activated, while the Etob receptor remains hormone responsive and produces a greater activation of its effector, adenylyl cyclase, than does the wild-type allele. 相似文献
77.
78.
Sil-Gu Mun Jung-Hyung Moon Ki-Man Choi Jin-Serk Baik Chang-Hee Lee 《Photonics Technology Letters, IEEE》2007,19(21):1729-1731
We propose and demonstrate a wavelength-division-multiplexed passive optical network by employing double-contact Fabry-Perot laser diodes (F-P LDs) without a seed light injection. To avoid the high mode partition noise at low frequency, we use a binary phase-shift keying as a modulation format at a low relative intensity noise window. An error-free transmission is achieved by compensating a lasing envelope shift due to temperature variation with the double-contact F-P LD. 相似文献
79.
明眸晧齿,笑容爽朗,脸部轮廓分明。看到袁泉,马上会有清冽甘甜的感觉,一如她的名字,仿佛夏日里活力天然的一泓清泉。从《春天的狂想》到娃哈哈广告中的美丽少女,袁泉给人的印象一直是青春、健康而甜美的,举手投足,一颦一笑,洋溢着独有的耀眼活力。不久前,这位活力闰女更是担任了“中国女性健康白皮书系列活动”的形象大使。作为宣传女性健康的代言人,袁泉呼吁,要让更多的女性认识到:健康的身体才是美丽人生的根基。[编者按] 相似文献
80.