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991.
年龄与成年人肾细胞癌临床分期的相关性分析 总被引:1,自引:0,他引:1
目的 探讨年龄与成年人肾细胞癌(renalcell carcinoma,RCC)临床分期的相关性。方法 回顾性分析310例病理确诊的成年RCC患者的临床资料,按年龄大小分为10岁以下组(≤40岁)、40-60岁组、60岁以上组(≥60岁),对三组患者的症状表现、病理学特点、淋巴结转移进行比较,以此了解年龄与成年人RCC临床分期的相关性。结果 40岁以下组偶发癌所占的比例明显低于10-60岁组(X^2=3.294,P=0.070),60岁以上组则显著低于40-60岁组(X^2=3.950,P=0.047);分化不良RCC的发生率随年龄增长逐渐降低(11.6%vs.5.2%vs.2.7%),且40岁以下组与60岁以上组相比较差异有显著性意义(P=0.038);淋巴结转移的发生率同样随年龄的增长而降低,且40岁以下组与其他两组相比较差异均有显著性意义(P〈0.05);三组临床分期的构成比差异有显著性意义(P〈0.01).Ⅰ期所占的比例随年龄增长逐渐降低,Ⅱ期在10岁以下组中所占的比例明显低于其他两组.而Ⅰ期+Ⅱ期在40-60岁组中的比例则明显高于其他两组。结论 偶发癌在各年龄组的不同比例值是导致不同年龄组患者临床分期出现差异的主要因素;淋巴结转移及分化不良RCC是导致这种差异的次要因素。 相似文献
992.
993.
A. Lau S. Wang J. Jiang A. Haig A. Pavlosky A. Linkermann A. M. Jevnikar 《American journal of transplantation》2013,13(11):2805-2818
994.
Objective: To study the differences of gene expression between earlier gestational skin and later gestational skin of rats with the aids of single primer amplification (SPA) and high-density oligonucleotide DNA array to understand the molecular mechanism of scarless healing. Methods: Total RNAs were isolated from fetal rat skin of the scarless (E15) and scar-forming (E18) periods of gestation (term =21.5 days). The RNAs from earlier gestational skin (EGS) and later gestational skin (LGS) were both reversely transcribed to cDNAs, then labeled with the incorporation of fluorescent dCTP for preparing the hybridization probes by SPA method. The mixed probes were then hybridized to the oligonucleotide DNA arrays which contained 5 705 probes representing 5 705 rat genes. After highly stringent washing, these DNA arrays were scanned for fluorescent signals to display the differentially expressed genes between the 2 groups of skin. Results: Among 5 705 rat genes, there were 53 genes (0.93%) with differentially expressed levels between EGS and LGS groups, 27 genes, including fibroblast growth factor 2 ( FGF2 ) and follistatin were up-regulated (0.47%) and 26 genes were down-regulated (0.46%) in fetal skin during scarless period versus scar-forming period. Higher expressions of FGF2 and follistatin in EGS than those in LGS were also revealed by RT-PCR method. Conclusions: High-density oligonucleotide DNA array provided a powerful tool for investigating differential gene expression in earlier and later gestational fetal skins. This technology validates that the mechanism of fetal scarless healing is very complicate and the change of many gene expressions is associated with fetal scarless healing. 相似文献
995.
996.
The targeting of phosphoinositide-3 kinase attenuates pulmonary metastatic tumor growth following laparotomy 下载免费PDF全文
OBJECTIVE: We aimed to characterize a potential role for phosphatidylinositol 3-kinase (PI3k) in leading to accelerated postoperative metastatic tumor growth. BACKGROUND: PI3k enhances tumor cell survival in part by phosphorylating Akt and reducing apoptosis. Postoperatively, apoptosis is reduced within local recurrences and distant metastases. This reduction is associated with the phenomenon of accelerated postoperative tumor growth. METHODS: Balb/c mice underwent a tail vein injection of 1x10 metastatic murine mammary adenocarcinoma 4T1 cells. Animals were divided into the following treatment groups (n=10/group): group A, controls; group B, DMSO intraperitoneally (IP) daily from days 14 to 21; group C, IP LY294002 daily from days 14 to 21; group D, laparotomy only; group E, laparotomy followed by IP DMSO for 7 days; and group F, laparotomy followed by LY294002 IP for 7 days. All laparotomies were performed on day 14. Animals were killed at day 28. Metastatic tumor burden was assessed using the lung/body weight ratio and a histologic metastatic index. Mitotic counts and apoptotic indices were established using a combination of hematoxylin and eosin histology and TUNEL immunohistochemistry. A parallel survival study was performed, and PI3k activity was assessed using western blots for phospho-Akt. RESULTS: Laparotomy was associated with increased systemic tumor burden (P=0.001). Postoperatively, LY294002 significantly attenuated metastatic tumor growth (P<0.001). Effective PI3k inhibition was confirmed by demonstrating a reduced Akt phosphorylation. Moreover, PI3k inhibition led to reduced proliferation, increased apoptosis (P<0.001), and enhanced postoperative survival (P<0.001). CONCLUSIONS: Targeting PI3k with postoperative LY294002 significantly attenuates the acceleration in postoperative metastatic tumor growth seen following laparotomy. 相似文献
997.
OBJECTIVE: To introduce a new technique of 1-stage reconstruction for thumb loss complicated by thumb-index web space contracture and to report its clinical effectiveness. METHODS: From November 1994 to September 2004 there were 11 patients with thumb loss and contracture in the thumb-index web space who had a combined transplantation of free tissues to reconstruct the missing thumb and to rebuild the web space. The reconstructive procedure used the second toe and the anterolateral thigh flap in 5 patients, the second toe and the scapular flap in 2, the big toe wraparound flap and the anterolateral thigh flap in 3, and the big toe wrapround flap and the scapular flap in 1. The 2 independent free tissues were connected together by a vascular combination to form an assembly with 1 common vascular pedicle, which then was anastomosed to the selected vessels in the recipient hand. In this vascular series the dorsalis pedis artery and the greater saphenous vein served as the common vascular pedicle of the flap transfers and the radial artery and the cephalic vein provided the recipient vessels. The outcomes of the reconstructions were evaluated using the Michigan Hand Outcomes Questionnaire. RESULTS: The flaps survived completely in all patients except 1. In this patient a small area in the distal part of the transplanted anterolateral thigh flap became necrotic but healed after dressing changes without the need for further surgical intervention. A mean follow-up period of 3.6 years showed a mean increase of 4.3 cm in the width of the thumb-index web space and a considerable improvement in overall hand function was noted on the Michigan Hand Outcomes Questionnaire with effect sizes of greater than 3 (large effect) in all domains. CONCLUSIONS: Combined transplantation of the second toe or the big toe wraparound flap and a free skin flap is suitable to reconstruct a missing thumb and repair the associated skin defect in the adjacent thumb-index web space. We found good functional recovery and an acceptable appearance in this series of patients.Type of study/level of evidence: Therapeutic, Level IV. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV. 相似文献
998.
The molecular and clinical impact of hepatocyte growth factor, its receptor, activators, and inhibitors in wound healing 总被引:1,自引:0,他引:1
Kevin Conway MRCS ; Patricia Price PhD ; Keith G. Harding FRCS ; Wen G. Jiang MD 《Wound repair and regeneration》2006,14(1):2-10
Wound healing involves a number of cellular and molecular events, many of which are controlled by soluble growth factors. In the process of healing, hepatocyte growth factor, a cytokine known to act as mitogen, motogen, and morphogen, has been postulated to play multiple roles during several stages of this complex biological process. Produced primarily by stromal fibroblasts, hepatocyte growth factor regulates angiogenesis, vascular permeability, cell migration, matrix deposition and degradation, and other biological processes. The current article discusses recent progress in understanding the multiple roles played by this growth factor in tissue repair. 相似文献
999.
Influence of CYP3A5 gene polymorphisms of donor rather than recipient to tacrolimus individual dose requirement in liver transplantation 总被引:3,自引:0,他引:3
BACKGROUND: Tacrolimus is a widely used immunosuppressant in organ transplantation, but it is characterized by a narrow therapeutic index and high interindividual variations of its pharmacokinetics. Tacrolimus is a substrate for CYP3A. It has been conjectured that CYP3A5 polymorphism is associated with tacrolimus pharmacokinetic variations. The objective of this study was to evaluate the contribution of polymorphisms of the donor and recipient CYP3A5 gene on tacrolimus disposition in liver transplantation. METHODS: Fifty-three liver transplant recipients treated with tacrolimus were enrolled in this study. Tacrolimus dosage and blood trough concentration were investigated at 1 week, 2 weeks, and 1 month after transplantation. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was applied to determine the genotype of CYP3A5 gene. RESULTS: The concentration/dose (C/D) ratios in patients with *1/*1(*1/*3) genotype donor were significantly lower than in patients with *3/*3 genotype donor at 2 weeks (P = 0.036) and 1 month (P = 0.021), but not at 1 week posttransplantation. Combination analysis showed that such significance still existed between CYP3A5 expressor group and nonexpressor group for both donor and recipient genotype. Also differences of C/D ratio between CYP3A5 expressor and nonexpressor donors in nonexpressor recipients were larger than those between recipients in nonexpressor donors. CONCLUSION: The large interindividual variation of tacrolimus dose requirement is influenced by the metabolic activity of CYP3A5. Polymorphisms of the donor CYP3A5 gene seem to contribute more to such variation than the recipient. A larger population and further studies are needed to explore the exact mechanisms for tacrolimus pharmacokinetics. 相似文献
1000.
Nerve conduit filled with GDNF gene-modified Schwann cells enhances regeneration of the peripheral nerve 总被引:4,自引:0,他引:4
A recombinant retrovirus vector containing the glial cell line-derived neurotrophic factor (GDNF) gene was constructed and transfected into Schwann cells (SCs) to investigate the possibility of GDNF transfection and functional expression of transfected SCs, including GDNF secretion and its mRNA expression. We found that transfection of the GDNF gene into SCs led to significantly enhanced expression of GDNF mRNA. The rate of GDNF secretion by GDNF-SCs was also increased. Functionally, more surviving motoneurons were seen when they were cocultured in GDNF-SC-conditioned medium than when they were in normal SC-conditioned medium. When bridging a rat sciatic nerve defect with a conduit filled with GDNF-transfected SCs, nerve regeneration was better than that of the control. In conclusion, transfection of SCs with the GDNF gene could enhance SC function. Application of genetically modified SCs could be a better way to promote nerve regeneration. 相似文献