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91.
Rosario Reyes Melissa Haendel Deanna Grant Ellie Melancon Judith S Eisen 《Developmental dynamics》2004,229(1):30-41
Rohon-Beard cells are large, mechanosensory neurons located in the dorsal spinal cord of anamniote vertebrates. In most species studied to date, these cells die during development. We followed labeled Rohon-Beard cells in living zebrafish embryos and found that they degenerate slowly, over many days. During degeneration, the soma shrinks and finally disappears, and the processes become beady in appearance and finally break apart, but they do not retract. Zebrafish Rohon-Beard cells apparently fragment their DNA, as revealed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) labeling, before undergoing degenerative morphologic changes. We also followed the development of labeled dorsal root ganglion neurons, as they are developing at the same stages that Rohon-Beard cells are degenerating. We found that, although axons of both cell types extend into similar regions, Rohon-Beard cells degenerate normally in mutants lacking dorsal root ganglia, providing evidence that interactions between the two cell types are not responsible for Rohon-Beard cell degeneration. Developmental Dynamics 229:30-41,2004. 相似文献
92.
Felix Eckstein Axel Weusten Corina Schmidt Ulrich Wehr Rüdiger Wanke Walter Rambeck Eckhard Wolf Subburaman Mohan 《Journal of bone and mineral research》2004,19(5):802-810
In this study we examined the effect of systemic overexpression of GH on bone in transgenic mice longitudinally in vivo over a period of 9 months. We observed substantially increased BMC in GH transgenic mice and a significant reduction in serum osteocalcin. GH effects on bone were strongly dependent on gender and developmental stage. INTRODUCTION: State-of-the-art bone marker and microimaging technology was applied in this longitudinal study to examine bone metabolism, BMC, bone density, and cortical bone structure over the life span of growth hormone (GH) transgenic (tg) mice. MATERIALS AND METHODS: Thirty-eight mice from four genetic groups (male, female, tg, and controls) were examined with DXA, and their femur and tibia were examined with peripheral QCT (pQCT). Osteocalcin (formation) and collagen cross-links (resorption) from serum and urine were also measured at postnatal weeks 3, 6, 9, 12, 18, 26, and 38. RESULTS: GH tg mice displayed a significant increase in body weight (up to 50%) and BMC (up to 90%), but serum osteocalcin was significantly reduced compared with controls. GH tg females (but not males) displayed increased trabecular density over controls up to week 12. In contrast, male (but not female) GH tg mice displayed a higher cortical cross-sectional area than controls. Cortical density was significantly lower in both male and female GH tg mice compared with control mice. CONCLUSIONS: The increase in BMC in GH tg mice is associated with reduced serum osteocalcin levels, indicating that bone turnover may be lower than in the control mice. On a structural level, bone responds to GH excess in a gender-specific manner, with alterations varying substantially between different developmental stages. 相似文献
93.
W Hunger-Dathe N Mosebach A S?mann G Wolf U A Müller 《Experimental and clinical endocrinology & diabetes》2006,114(1):11-17
AIM: Prevalence of glucose metabolism disorders in women six years after gestational diabetes in the index pregnancy (GDM). METHOD: 227 Caucasian women who developed GDM between 1995 and 1996 were investigated; 173 women (BMI 27.5+/-6.0 kg/m2) received 75 g oGGT on average 5.8+/-2.0 years after delivery. RESULTS: Impaired glucose metabolism was found in 31.2%, IGT or IFG 19.1%, diabetes mellitus type 2 (DM2) 9.2%, diabetes mellitus type 1 (DM1) 2.3%, second GDM 0.6%. 27.2% (BMI 25-29.9 kg/m2) were overweight, 23.1% suffered from obesity (BMI 30-39.9 kg/m2) and 5.2% morbid obesity (BMI>or=40 kg/m2). In comparison to a healthy control group, women with DM2 at re-examination were: older in age (32.1+/-5.9 vs. 29.1+/-4.8 years, p<0.05), had higher BMI (29.4+/-6.9 vs. 24.6+/-4.8 kg/m2, p<0.05), higher fasting blood glucose (6.5+/-1.9 vs. 5.2+/-0.9 mmol/l, p<0.05), earlier diagnosis of GDM (25+/-8 vs. 29+/-5 SSW, p<0.05), more frequent insulin therapy during pregnancy (75 vs. 24%) and had significantly higher insulin- and C-peptide for all measures of the oGTT, whereas HbA1c was not different (4.9+/-0.5 vs. 4.8+/-0.3%, n. s.). CONCLUSION: In an average of 5.8 years after the diagnosis of GDM, the majority of women still have chronic insulin resistance. One third has either IGT, IFG or diabetes mellitus. Therefore, a long term follow-up is strongly recommended for women diagnosed with GDM. 相似文献
94.
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97.
Eileen Trafimow Ph.D. Marie Weissbourd Ph.D. Judith Wilen Ph.D. 《Journal of Child and Adolescent Group Therapy》1992,2(3):141-148
Traditionally, psychotherapy groups for children included only relatively intact youngsters. This paper describes a group consisting of four (near) psychotic children and two co-therapists which met for over three years. The developmental changes which occurred in the group over the course of time will be identified and discussed using a neo-psychoanalytic, object relations framework. 相似文献
98.
Ming Li Allison Martin Cheng Wen Steven W. Turner Lynley K. Lewis Judith A. Whitworth 《Clinical and experimental pharmacology & physiology》1995,22(12):919-923
1. We tested the ability of ouabain to cause chronic hyper tension by continuously infusing ouabain for 28 days (mini-osmotic pump implantation; i.p.). The blood pressure and metabolic effects of sham (150 mmol/L NaCI; n= 12) or ouabain infusion (10 μg/kg per day; n= 14; 100 μg/kg per day; n = 14) were examined in conscious Sprague-Dawley rats. 2. Plasma ouabain concentrations measured after 28 days of ouabain infusion were as follows: sham, not detectable (n= 11); ouabain 10 μg/kg per day, 0.60 ± 0.07 nmol/L (n= 14); and ouabain 100 μg/kg per day, 7.17 ± 0.57 nmol/L (n= 14; P < 0.001). 3. Sham or ouabain infusion did not alter food intake, bodyweight, water intake or urine output in conscious rats. 4. Blood pressure was not altered by sham treatment. Ouabain at 10 μg/kg per day or 100 μg/kg per day did not produce consistent rises in blood pressure. Ouabain at 10 μg/kg per day increased blood pressure on treatment day 12 only (+ 6mmHg; P < 0.05), while at 100μg/kg per day blood pres sure increased on treatment days 16 (+ 9 mmHg; P < 0.05) and day 18 (+ 8mmHg; P < 0.05) only. There was no significant difference in blood pressure between sham and ouabain groups. 5. Renal blood flow was decreased in rats infused with ouabain at 10 μg/kg per day (2.0 ± 0.3 mL/min per 100 g body-weight; n= 5; P < 0.01) and 100 μg/kg per day (2.2 ± 0.4 mL/ min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (3.5 ± 0.2 mL/min per 100 g bodyweight; n= 6). Renal vascular resistance was increased in rats treated with ouabain at 10 μg/kg per day (65.5 ± 12.6 mmHg/mL per min per 100 g bodyweight; n= 5; P < 0.01) and 100 μg/kg per day (66.0 ± 15.6 mmHg/mL per min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (32.6 ± 2.5 mmHg/mL per min per 100 g bodyweight; n= 6). 6. High plasma concentrations of ouabain do not cause consistent increases in blood pressure in conscious Sprague-Dawley rats. 相似文献
99.
Low molecular weight heparin and prevention of postoperative thrombosis in abdominal surgery. 总被引:3,自引:0,他引:3
K Koppenhagen J Adolf M Matthes E Tr?ster J D Roder S Hass H M Fritsche H Wolf 《Thrombosis and haemostasis》1992,67(6):627-630
In a prospective, double-blind, randomized multicenter trial the efficacy and safety of low molecular weight heparin and unfractionated heparin were compared for the prevention of postoperative deep vein thrombosis in patients undergoing abdominal surgery. Six hundred and seventy-three patients were randomly allocated to the two prophylaxis groups; 20 of these, however, did not undergo surgery and did not receive any prophylaxis. Of the remaining 653 patients 323 received one subcutaneous injection of 3,000 anti-Xa units of low molecular weight heparin and 330 received subcutaneously 5,000 U heparin three times a day. Treatment was initiated 2 h preoperatively and continued for 7 to 10 days. The occurrence of DVT was determined by the 125I-labelled fibrinogen uptake test and phlebography. Venous thrombosis was diagnosed in 24 of 323 patients (7.4%) treated with low molecular weight heparin and in 26 of 330 patients (7.9%) treated with low-dose heparin. DVT of proximal veins was detected in four patients of the low molecular weight heparin group and in three patients of the low-dose heparin group. During the observation period three pulmonary emboli - one fatal and two non-fatal - occurred in patients receiving prophylaxis with low-dose heparin. No pulmonary embolism was found in patients treated with low molecular weight heparin. Both prophylactic schemes were well tolerated. Intra- and postoperative blood loss, incidence of wound hematoma, frequency and volume of intra- and postoperative blood transfusion were similar in both groups with a slight advantage for the low molecular weight heparin group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
100.