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101.
目的:探讨人脑胶质瘤中βcatenin的表达及与细胞增殖的相关性。方法:用免疫组化法观察了47例胶质瘤标本βcatenin、cyclinD1、增殖细胞核抗原(PCNA)的表达,并分析其相关性。结果:在胶质瘤中βcatenin、cyclinD1、PCNA均随肿瘤恶性程度增高而增高(P分别为0.017、0.017、0.027),相关分析发现βcatenin、cyclinD1、PCNA的表达两两相关(P<0.001,P<0.001和P=0.005)。结论:βcatenin表达水平的异常与胶质瘤细胞周期调节紊乱、增殖指数上升有关,因此可能是控制肿瘤细胞增殖活性的候选基因之一。 相似文献
102.
Kiyoshi Hashizume Kazuo Ichikawa Satoru Suzuki Teiji Takeda Keishi Yamauchi Mutsuhiro Kobayashi Xiao-Yun MA 《Journal of bone and mineral metabolism》1992,10(2):39-49
Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction
on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets
would show any modification of parathyroid hormone (PTH) and calcitonin (CTN).
The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into
two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were
measured by competitive protein binding assays before and after each program.
The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that
(256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral
calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in
the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine
were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower
in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma
1,25-(OH)2-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When
the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase
in the 1,25-(OH)2-vitamin D levels, whereas their CTN levels were unchanged.
These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as
for a low serum level of CTN in patients with NIDDM. 相似文献
103.
给出了用“混合型”雅可比级数的泰勒平均逼近黎普希兹函数类的点态估计。 相似文献
104.
Organization of dopamine D1 and D2 receptors in human striatum: receptor autoradiographic studies in Huntington's disease and schizophrenia 总被引:3,自引:0,他引:3
The technique of quantitative autoradiography was used to examine the effects of Huntington's disease (HD) and schizophrenia on the organization of striatal dopamine (DA) D1 and D2 receptors. Whereas the striatum of HD cases showed a reduction in the density of D1 ([3H]SCH 23390) and D2 ([3H]spiroperidol) receptors, the patterning of D2 receptor loss did not match that of the D1 receptor loss. The HD loss of D1 D1 receptors (65%) is far greater than the loss of D2 receptors (28%). Whereas there was a dorsal-ventral gradient of effect on both receptor subtypes, the effects of HD on D2 receptors in the ventral putamen (PUT) and nucleus accumben septi (NAS) were minimal. Similarly, muscarinic M1 and M2 receptors demonstrate different patterns of alteration in HD. The M2 subtype, labeled with [3H]N-methylscopolamine (in the presence of excess pirenzepine to occlude M1 sites), was depleted far more than the M1 receptor subtype, labeled with [3H]pirenzepine. Although the effects of HD on [3H]mazindol labeling of DA terminals were more heterogeneous, there appeared to be a relative preservation of this afferent input to the striatum of the HD cases. In the schizophrenic cases, our autoradiographic studies confirm previous reports of an elevation of D2 receptor density in the striata of many schizophrenics. This increase was evident even though two of the three cases were known to have not been treated with neuroleptics, and the third case may also have been drug naive. However, the increase was far greater in the NAS (164%) and ventral PUT (173%) than more dorsally in the striatum (68%). The density of D1 receptors and DA terminals labeled with [3H]mazindol in the striatum of schizophrenics was not significantly different from that of control cases. Thus in both HD and schizophrenia, the ratio of D2/D1 receptors is altered in favor of the D2 population, particularly in the NAS. 相似文献
105.
《Journal of labelled compounds & radiopharmaceuticals》2006,49(8):707-732
Results are reported on the regioselective C‐deuteriation of 2‐methyl‐tetralone using a series of D‐sources and tertiary amines as potential mediators. The results presented further aid the understanding of kinetic deuteriation of both ‘base‐containing’ and ‘base‐free’ enolates. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
106.
K. Nakamura T. Saito T. Nishiwaki K. Ueno M. Nashimoto Y. Okuda Y. Tsuchiya R. Oshiki K. Muto M. Yamamoto 《Osteoporosis international》2006,17(8):1202-1207
Introduction A few epidemiologic studies have comprehensively attempted to identify risk factors for low bone mineral density (BMD) in elderly Asian women. The purpose of this study was to identify demographic, lifestyle, and biochemical factors correlated with BMD in elderly Japanese women 69 years of age and over.Methods The study design was cross-sectional. The subjects were 583 ambulatory women aged 69 years and over, and their average age was 74.3 (SD 4.4) years. Predictor variables were age, reproductive history, anthropometric indices, grip strength, calcium intake, lifestyle information, and serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D (1,25(OH)2D), osteocalcin (OC), and undercarboxylated osteocalcin (ucOC) values. The outcome variable was forearm BMD measured with a DTX-200 osteometer.Results Simple linear regression analyses showed that BMD was significantly positively associated with body height, weight, body mass index, grip strength, serum albumin concentration, and “housework,” and negatively associated with age, years since menopause, age at menarche, number of children, serum 1,25(OH)2D concentration, serum OC concentration, and ucOC concentration. The stepwise multiple regression analysis showed that weight (β=0.00316, SE=0.00028, R2=0.180), age (β=−0.00321, SE=0.00050, R2=0.108), log-transformed serum OC (β=−0.0445, SE=0.0064, R2=0.053), log-transformed serum 1,25(OH)2D (β=−0.0401, SE=0.0074, R2=0.050), “farmwork” (β=0.00904, SE=0.00426, R2=0.005), and serum 25(OH)D concentration (β=0.000281, SE=0.000120, R2=0.003) were significantly associated with BMD.Conclusion It was concluded that body weight is a major predictor of forearm BMD among the factors measured in this study in independent Japanese women 69 years of age and over and that serum 1,25(OH)2D concentration may be associated with cortical BMD. Maintenance of body weight is very important for maintaining BMD in this population, unless a large weight aggravates obesity-related diseases. A follow-up study is needed to confirm these findings. 相似文献
107.
Hiroo Takehara M.D. Akira Okada M.D. Masaharu Nishi M.D. Katsuhiro Masamune M.D. 《Pediatrics international》1992,34(5):569-572
We present a case of Peutz-Jegher's syndrome in an 18 year old female who was followed for gastrointestinal polyps for 13 years from the age of 5 years. The patient was treated four times with surgical or endoscopic polypectomy for gastrointestinal polyps. At the age of 14 years, a combined surgical and endoscopic approach for the management of Peutz-Jegher's syndrome was carried out. A large polyp of the ileum required enterotomy for its removal, and another smaller polyp of the upper jejunum was identified and removed by intra-operative total enteroscopy via the anus. Intra-operative enteroscopy allows one to identify polyps that would previously have been missed. A more complete polypectomy can be performed using this technique, allowing the patient with Peutz-Jegher's syndrome a longer interval between laparotomies and a reduction in symptoms attributed to polyps. 相似文献
108.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc. 相似文献
109.
Dr. Gerold Wetscher MD Elizabeth Redmond MD Christine Watfah MD Galen Perdikis MD Michael Gadenstätter MD Rudolph Pointner MD 《Digestive diseases and sciences》1994,39(12):2511-2515
Bone disorders following gastrectomy were studied by measuring absolute and relative bone mineral density of the Wards triangle, serum 1,25-(OH)2-D, alkaline phosphatase, and total serum calcium. The subjects were 20 males who had undergone total gastrectomy not more than three months previously (group A1). Seventeen of these patients were reviewed three years later (group A2). Absolute and relative bone density were significantly lower in group A2 than in A1 (0.52 ± 0.011 g/cm2 versus 0.6 ± 0.014 g/cm2,P<0.01 and 85.5 ± 1.4% age-matched control versus 95 ± 1.3%,P<0.01). 1,25-(OH)2-D was significantly lower in group A2 than in group A1 (14.3 ± 0.97 pg/ml versus 20.6 ± 1.02 pg/ml,P<0.01). There was no difference in alkaline phosphatase and calcium serum concentration. The mean weight loss was 6.26 ± 0.57% over the follow-up period, and weight loss correlated with absolute and relative bone density (r=–0.74,P<0.01). There was a positive correlation between 1,25-(OH)2-D and absolute or relative bone density (r=0.67,r=0.62 andP<0.01). These data suggest that bone density decrease has already occurred three years after total gastrectomy and is positively correlated to 1,25-(OH)2-D deficiency. As no differences in serum alkaline phosphatase and serum calcium concentration were found, these factors are of little value for the early detection of postgastrectomy bone disorders, whereas weight loss is a valuable screening parameter. 相似文献
110.
新生大鼠反复惊厥对NMDA受体表达的长期影响 总被引:6,自引:0,他引:6
目的:研究反复惊厥对大鼠脑内N-甲基-D-天门冬氨酸(NMDA)受体表达,以及成年期认知功能和惊厥阈的长期影响。方法:生后6d(用P6表示,下同)的Wistar大鼠随机分成两组,每组6只,惊厥组每日吸入三氟乙醚诱导惊厥发作1次,每次持续30min,连续6d;对照组同样操作但不吸入三氟乙醚。两组大鼠于P60-P65行Morris水迷宫实验,检测大鼠的学习记忆功能。于P75时给予大鼠腹腔注射戊四唑(PTZ)测定大鼠的惊厥阈。随即断头处死大鼠,分离大脑皮质和海马,匀浆提取细胞膜蛋白,应用免疫印记法测定NMDA受体亚基l(NRl)和NR2A-2D表达的变化。结果:从P6l至P65,两组大鼠寻找平台时间均逐渐缩短,惊厥组大鼠在P65的平均寻找平台时间较对照组显著延长。惊厥组大鼠注射PTZ后发生惊厥的潜伏期与对照组比较差异无显著性。在大脑皮层,惊厥组大鼠较对照组NRl和NR2B表达水平明显下调,在海马这两种亚基表达水平无明显改变,在大脑皮层和海马区,惊厥组较对照组NR2A表达水平明显下调,NR2C表达水平明显上调。两组在皮层和海马均无NR2D表达。结论;新生大鼠反复惊厥可导致远期认知障碍,同时伴有NMDA受体的数量和结构上的长期改变,NMDA受体表达的这种改变可能在发育期惊厥导致的脑长期认知功能损害中起重要作用。 相似文献