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21.
Colorectal cancer (CRC) is one of the most common malignancies worldwide. The incidence of CRC in the Chinese population has increased dramatically during the last two decades; however, nonrandom chromosomal alterations in Chinese patients have not been described. In the present study, comparative genomic hybridization (CGH) was applied to detect recurrent chromosome alterations in 26 primary colorectal carcinomas and 21 colorectal adenomas from Chinese patients. In CRC, several recurrent chromosomal changes were found, including gains of 8q (14/26 cases, 54%), 20q (54%), 3q (50%), 13q (50%), 5p (46%), 7p (42%), 7q (42%), and 12p (38%) and losses of 18q (65%) and 17p (42%). From comparison with previous CGH studies, the frequent gains of 3q and 12p might be distinctive occurrences in Chinese patients. The distribution of frequently found chromosomal alterations in different locations was studied. The gain of 20q was more frequently found in colon cancer (P<0.01) and the gain of 12p was more frequently found in rectal cancer. Chromosomal alterations were found in 19/21 of adenomas; the most frequent chromosomal alteration was the loss of 18q (9/21 cases, 43%). These recurrent alterations provide several starting points for the isolation of candidate oncogenes and tumor suppressor genes.  相似文献   
22.
c AMP反应成分结合蛋白 (c AMP response elem ent-binding protein,CREB)是一种转录因子 ,它在磷酸化之后可调节靶基因的转录。 CREB在 13 3位置的丝氨酸的磷酸化 ,与脊髓中伤害性传入的处理有关 ,本文作者等用特殊抗体对此进行了免疫细胞化学研究。在正常大鼠 ,虽然几乎所有脊髓神经元的核中都可见 CREB的轻度着色 ,但磷酸化的 CREB仅见于双侧腰段脊髓的 ~ 层 (75± 15 vs60± 18)和 层 (9± 3 )。用福尔马林注射引起一侧后脚掌出现炎症时 ,可在双侧腰段脊髓看到磷酸化CREB细胞核的快速 (小于 5 min)和节段性的显著增多 ;它们主要分布在双侧背角表层 ~ 层 (2 5 4± 2 0 vs 2 62± 2 3 )、 层(115± 13 )和双侧 ~ 层 (3 46± 2 0 vs3 2 8± 2 6) ;而在对照和炎症组大鼠的胸段脊髓中均未见磷酸化 CREB的增加。在注射CFA诱发一侧炎症或切断一侧坐骨神经的实验组大鼠 ,也可看到至少延续到第三天的强而双侧性的 CREB的磷酸化。这种由一侧后肢伤害性传入引致腰段脊髓中镜像式双侧 CREB磷酸化的出现 ,与一般看到的损伤传入只在同侧脊髓背角引起某些神经化学改变的结果不同 ,可能是人神经损伤后或在实验动物中出现对侧镜像式疼痛过敏现象的基础  相似文献   
23.
The parasitic copepod Sinergasilus major is an important pathogen of grass carp Ctenopharyngodon idella. To understand the immune response of grass carp to the copepod infection, suppression subtractive hybridization method was employed to characterize genes up-regulation during the copepod infection in liver and gills of the fish. One hundred and twenty-two dot blot positive clones from infected subtracted library were sequenced. Searching available databases by using these nucleotide sequences revealed that 23 genes are immune-related, including known acute-phase reactants, and four novel genes encoding proteins such as source of immunodominant MHC-associated peptides (SIMP), TNF receptor-associated factor 2 binding protein (T2BP), poliovirus receptor-related protein 1 precursor, glycoprotein A repetitions predominant (GARP). The differential expression of seven immune genes, i.e. GARP, alpha-2-macroglobulin, MHC class I, C3, SIMP, T2BP, transferrin, as a result of infection was further confirmed by RT-PCR, with the up-regulation of alpha-2-macroglobulin, MHC class I, C3, SIMP and T2BP in the liver of infected fish, and down-regulation of SIMP in the gills of infected fish. The present study provides foundation for understanding grass carp immune response and candidate genes for further analysis.  相似文献   
24.
研究生物工程活性角膜的生物相容性,为进一步临床应用提供理论基础。猪角膜基质脱细胞并去除免疫源性物质形成网状半透明生物材料,将培养的角膜基质细胞与生物材料复合构建生物工程活性角膜基质。对复合物进行倒置显微镜和扫描电镜检测细胞附着情况及材料的细胞相容性;将活性角膜基质移植入新西兰兔角膜囊袋内.细胞用BrdU标记检测在体内移植过程中的存活及转归,不同时间观察角膜的生物相容性及改建情况。结果显示脱细胞基质材料的细胞相容性较好,细胞种植后可存活、黏附并增殖;移植区细胞可有BrdU阳性着色,4周后角膜开始透明,8周后角膜改建基本完成。  相似文献   
25.
mPEG表面修饰的PLGA嵌段共聚物的血液相容性评价   总被引:3,自引:0,他引:3  
本实验室设计合成了三种不同LA/GA比例的mPEG修饰PLGA(PELGA,含15%mPEG),为了评价它们的血液相容性,我们以硅化玻璃试管为阴性对照,未硅化的试管为阳性对照,参照国际标准(ISO10993)和《中华人民共和国国家标准GB/T16886医疗器械生物学评价》方法进行了体外评价实验。试验包括溶血率实验,血小板黏附实验,动态凝血时间实验,凝血时间实验,血浆复钙时间实验和凝血酶原时间实验等综合评价指标。结果表明,合成材料具有优良的血液相容性,材料制成的纳米粒有望应用于静脉注射。  相似文献   
26.
Wang  Yu  Lin  Zhijian  Zhang  Bing  Nie  Anzheng  Bian  Meng 《Nutrition & metabolism》2021,18(1):1-11
The study of sex differences in hyperuricemia can provide not only a theoretical basis for this clinical phenomenon but also new therapeutic targets for urate-lowering therapy. In the current study, we aimed to confirm that estradiol can promote intestinal ATP binding cassette subfamily G member 2 (ABCG2) expression to increase urate excretion through the PI3K/Akt pathway. The estradiol levels of hyperuricemia/gout patients and healthy controls were compared, and a hyperuricemia mouse model was used to observe the urate-lowering effect of estradiol and the changes in ABCG2 expression in the kidney and intestine. In vivo and in vitro intestinal urate transport models were established to verify the urate transport function regulated by estradiol. The molecular pathway by which estradiol regulates ABCG2 expression in intestinal cells was explored. The estradiol level of hyperuricemia/gout patients was significantly lower than that of healthy controls. Administering estradiol benzoate (EB) to both male hyperuricemic mice and female mice after removing the ovaries confirmed the urate-lowering effect of estradiol, and hyperuricemia and estradiol upregulated the expression of intestinal ABCG2. Estradiol has been confirmed to promote urate transport by upregulating ABCG2 expression in intestinal urate excretion models in vivo and in vitro. Estradiol regulates the expression of intestinal ABCG2 through the PI3K/Akt pathway. Our study revealed that estradiol regulates intestinal ABCG2 through the PI3K/Akt pathway to promote urate excretion, thereby reducing serum urate levels.  相似文献   
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28.
侧方淋巴引流是低位直肠癌3个重要的淋巴引流方向之一。沿引流途径清扫淋巴结是直肠癌根治术基本要求,也决定淋巴结清扫范围。但侧方淋巴结是区域淋巴结还是远处淋巴结,一直存在争议。这带来新辅助放化疗和侧方淋巴结清扫、以及新辅助放化疗对侧方淋巴结转移疗效的争议。笔者综合分析国内外研究进展,对直肠癌侧方淋巴结转移规律、影响侧方淋巴结转移复发危险因素以及放化疗前后MRI检查对侧方淋巴结评估等进行深入阐述,并结合临床实践,探讨进展期低位直肠癌新辅助放化疗后侧方淋巴结清扫的选择和意义。  相似文献   
29.
ObjectiveTo explore the effect of a PEEK material‐based external fixator in the treatment of distal radius fractures with non‐transarticular external fixation.MethodsThere were 48 patients in this prospective comparative study. They were divided into two groups according to the materials used: the PEEK group and the titanium group. Wrist dorsiflexion, palmar flexion, pronation, supination, radial deviation, ulnar deviation, grip strength of the palm on the affected side, kneading force, Visual Analogue Scale/Score (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, operation time, frequency of fluoroscopy procedures, and X‐ray results were compared between the two groups. Functional recovery was evaluated at the last follow‐up according to the wrist joint evaluation criteria.ResultsThe baseline data were comparable between the two groups, and no significant differences were found in age, sex, fracture types (P > 0.05). There was no significant difference between the two groups in the results of DASH, grip strength, and recovery of pinch force and wrist function (dorsiflexion, clavicle, ulnar deviation, deviation, pronation, and supination) (P > 0.05). Normal limb function was achieved in the two groups of patients at an average of 6 weeks after surgery, and there was no significant difference in X‐ray examination radial height (10.60 ± 1.59 vs 11.00 ± 1.53, P = 0.687), radial inclination (1.11 ± 0.24 vs 1.12 ± 0.24, P = 0.798), volar tilt (10.33 ± 2.13 vs 10.00 ± 2.08, P = 0.660), ulnar variance (20.87 ± 3.00 vs 20.38 ± 3.04, P = 0.748), and step‐off persistence (1.73 ± 0.69 vs 1.68 ± 0.72, P = 0.425) between the two groups (P > 0.05). However, the operation time (54.80 ± 12.20 vs 85.23 ± 15.14, P = 0.033) and number of fluoroscopy procedures (36.93 ± 6.89 vs 64.77 ± 9.74, P = 0.000) in the PEEK group were significantly reduced compared with those in the titanium group.ConclusionCompared with the traditional titanium external fixator, the PEEK composite external fixator has advantages, such as a shorter operation time and fewer fluoroscopy procedures when used to treat different types of distal radius fracture.  相似文献   
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