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111.
测定72例健康老年人(60-84岁)和65例健康青中年人(20-50岁)血清和尿β2微球蛋白(β2m),发现前血清β2m浓度比后明显增高(p<0.001);老年组≥70岁尿液β2m浓度也明显增高(p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低,以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。  相似文献   
112.
BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer.  相似文献   
113.
Aims The Type 1 diabetes susceptibility locus, IDDM2, has been mapped to a variable number of tandem repeats (VNTR) region 5′ upstream of the insulin (INS) and insulin‐like growth factor (IGF2) genes on chromosome 11p15. The function of the VNTR is uncertain; however, it may influence the thymic expression of the insulin gene and affect the development of immune self‐tolerance. The aim of this study was to investigate whether the INS VNTR region is a Type 1 diabetes‐specific locus or acting as a general autoimmunity gene. Methods We genotyped the INS‐IGF2 VNTR [using the surrogate INS?23 HphI single nucleotide polymorphism (SNP)] in 823 Graves’ disease (GD)/multiple sclerosis (MS) families, 1433 GD/MS patients and 837 healthy control subjects. Results We found no evidence of excess transmission of the allele associated with Type 1 diabetes to individuals affected by GD or MS within the families. Analysis of the case–control dataset showed no genotypic or allelic difference between the two populations. Conclusions These data suggest that the INS‐IGF2 VNTR is acting as a Type 1 diabetes‐specific susceptibility gene rather than as an influence on general autoimmunity.  相似文献   
114.
Summary Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity.PK 9084 (5–40 mg/kg, ip) and CGS 9896 (2–20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15–1788 (15 mg/kg). CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH.Differently from anxiolytics, MK-801 (0.5–1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice.  相似文献   
115.
我院自2001年1月-2005年12月,在常规综合治疗的基础上采用中药合654-2治疗重度黄疸型肝炎42例,疗效较满意,报道如下。  相似文献   
116.
Summary A new acid thiol, 2-mercaptopropionate, has been identified by GC-MS in urine from cystinuric patients on treatment with 2-mercaptopropionylglycine. The amount excreted was 50–300 µmol/24 h and it was correlated with the oral dose of 2-mercaptopropionyl-glycine. The observation may be of clinical importance as the metabolite could be a potential hazard in oxidation of fatty acids.  相似文献   
117.
Background A recombinant form of the α2(IV)NC1 domain of type IV collagen has been shown to have potent anti-angiogenic activity although this peptide has not been studied in the context of proliferative retinopathies. In the current investigation we examined the potential for α2(IV)NC1 to regulate retinal microvascular endothelial cell function using a range of in vitro and in vivo assay systems. Materials and methods α2(IV)NC1 at concentrations between 0.1 and 1 μg/ml was added to retinal microvascular endothelial cells (RMECs) followed by assessment of cell attachment, proliferation and survival. This agent was also tested within a novel in vitro three-dimensional retinal angiogenesis assay and the number of angiogenic sprouts quantified. α2(IV)NC1 was also delivered intra-vitreally to mice with oxygen-induced proliferative retinopathy (OIR) and neovascularisation evaluated in comparison with vehicle-treated controls. Results RMECs treated with α2(IV)NC1 (0.1, 0.5 and 1 μg/ml) showed delayed attachment at 3 h post-seeding, although this deficit had been restored at the 6-h time point. BrdU assay of DNA replication revealed that confluent RMECs treated with α2(IV)NC1 showed no measurable response in comparison with vehicle-treated controls. By contrast, proliferation of sub-confluent RMECs was significantly reduced by α2(IV)NC1 at 0.5 μg/ml (P<0.01). α2(IV)NC1 also induced apoptosis in RMECs and inhibited angiogenesis of pre-existing retinal vascular networks in vitro (P<0.001). Intra-vitreal injection of α2(IV)NC1 in the OIR model significantly inhibited pre-retinal neovascularisation compared with vehicle-treated controls (P<0.001). Conclusion α2(IV)NC1 inhibits angiogenesis in the retinal microvasculature. This recombinant protein has potential for the treatment of neovascularisation in proliferative retinopathies. BioStratum Inc. did not sponsor this research in any way. None of the authors are paid consultants with this company.  相似文献   
118.
Klein [Klein, A. S. (2006). Separating transducer nonlinearities and multiplicative noise in contrast discrimination. Vision Research, 46, 4279-4293] questions the existence of intrinsic singularities in two-alternative force-choice (2AFC) Signal Detection Theory (SDT) models, suggesting that the singularities found in Katkov et al. [Katkov, M., Tsodyks, M., & Sagi, D. (2006a). Singularities in the inverse modeling of 2AFC contrast discrimination data. Vision Research, 46, 259-266; Katkov, M., Tsodyks, M., & Sagi, D. (2006b). Analysis of two-alternative force-choice Signal Detection Theory model. Journal of Mathematical Psychology, 50, 411-420] are due to discarding higher order terms in the Taylor expansion of d' and/or limited to steep psychometric functions. Here we provide some simple intuitive examples that illustrate the results described in Katkov et al. (2006a, 2006b). We show, for the constant noise model, that singularities exist when exact values of d' are computed and that the singularities are not limited to steep psychometric functions. In these cases the disambiguation of the different models requires millions of trials.  相似文献   
119.
Introduction Hypothalamic hamartomas are congenital malformations. Clinically, they can be asymptomatic, but they cause seizures, mental retardation and precocious puberty in many cases. Case report A 20-day-old boy with hypothalamic hamartoma and bilateral anophthalmia was presented. Except those, no other congenital anomaly was detected. Conclusion This is a rare case of hypothalamic hamartoma with bilateral anophthalmia. The mutations at SOX2 has an important role in the developing brain and eyes.  相似文献   
120.
Physical activity is an important, but often underused, therapeutic strategy within diabetes care. To date, little is known about the best way to promote physical activity in diabetes care. Physical activity consultation is an intervention designed to promote physical activity behaviour change. This article provides guidelines on how to conduct a physical activity consultation with people who have Type 2 diabetes, and reviews the evidence surrounding the effectiveness of this intervention in this population. The trans-theoretical model is the underlying theory of behaviour change for the physical activity consultation intervention. The review identifies research which supports the use of this model for understanding physical activity behaviour in people with Type 2 diabetes. The review outlines a number of modifiable variables associated with physical activity behaviour change in this population. How each of these variables is addressed within the guidelines for conducting a physical activity consultation is identified. Finally, limited but consistent research highlights the effectiveness of physical activity consultation for promoting physical activity in people with Type 2 diabetes.  相似文献   
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