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11.
Adult female rats were i.p. infused (Alzet osmotic minipumps) with neurotensin (NT, 2 micrograms/rat/day for 7 days), arginine-vasopressin (AVP, 2 micrograms/rat/day for 8 days), bombesin (BM, 0.75 microgram/rat/day for 7 days) or injected with neuropeptide Y (NPY, 0.5 microgram/rat twice a day for 4 days). NT infusion increased absolute and relative thyroid gland weight and decreased serum T4 level, while serum TSH and T3 levels remained unchanged. AVP treatment increased thyroid gland weight and serum TSH and T4 levels and a similar effect was induced by prolonged BM infusion. On the other hand, NPY administration had no effect either on thyroid gland weight or on serum TSH, T4 and T3 levels. Results of the present study thus clearly demonstrate a potent stimulatory action of AVP and BM on thyroid gland function and suggest that this effect is mediated by the pituitary gland. On the contrary, prolonged NT infusion decrease serum T4 level while NPY had no effect on thyroid gland function. 相似文献
12.
13.
Hypoxiaisadirectfactorcausinghypoxicpul monaryhypertension (HPH) .hypoxiainduciblefac tor 1α (HIF 1α)isfoundtobethemostcrucialfactorsofarwhichmediatesthecellularresponsetohypoxi a[1] .OurpreviousstudyrevealedthatoverexpressionofHIF 1andendothelin 1(ET 1… 相似文献
14.
A tumor-targeted and conditionally replicating oncolytic adenovirus vector expressing TRAIL for treatment of liver metastases. 总被引:3,自引:0,他引:3
Pavel Sova Xiao-Wei Ren Shaoheng Ni Kathrin M Bernt Jie Mi Nancy Kiviat André Lieber 《Molecular therapy》2004,9(4):496-509
We have constructed a new capsid-modified adenovirus (Ad) vector that specifically replicates in tumor cells and expresses TNF-related apoptosis-inducing ligand (TRAIL). The Ad capsid contains short-shafted fibers derived from Ad serotype 35, which allow for efficient infection of malignant tumor cells, and largely avoids innate toxicity after intravenous application. Replication-dependent homologous recombination in Ad genomes was used to achieve tumor-specific expression of Ad E1a (to mediate viral replication) and TRAIL (to mediate apoptosis and enhance release of progeny virus from infected cells). We demonstrated that our oncolytic vector (Ad5/35.IR-E1A/TRAIL) induced apoptosis in human tumor cell lines derived from colorectal, lung, prostate, and liver cancer. Both in vitro and in vivo tumor models showed efficient intratumoral spread of this vector. In a model for metastatic colon cancer, tail vein infusion of Ad5/35.IR-E1A/TRAIL resulted in elimination of preestablished liver metastases. Intravenous injection of this vector caused a transient elevation of serum glutamic pyruvic transaminase in tumor-bearing mice, which we attributed to factors released from apoptotic tumor cells. Liver histology analyzed at day 14 after virus injection did not show signs of hepatocellular damage. This new oncolytic vector represents a potentially efficient means for gene therapy of metastatic cancer. 相似文献
15.
We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels. 相似文献
16.
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services. 相似文献
17.
实验性室间隔缺损心肌血管紧张素Ⅱ受体表达的变化 总被引:1,自引:1,他引:0
目的 探讨实验性室间隔缺损 ( VSD)动物左右心室心肌血管紧张素 受体的改变。方法 建立猪实验性室间隔缺损动物模型 ,术后 1月取左右心室组织 ,通过放射性配体受体结合分析法测定每 10 6个细胞上血管紧张素 受体 ( AT1 R、AT2 R)的最大结合量 ( Bmax)和平衡解离常数 ( KD)。结果 假手术组与正常组动物受体的 Bmax和KD改变无统计学意义 ,手术组动物左室 AT1 R、右室 AT1 R和 AT2 R的 Bmax值 (分别为 188.42± 13 3 .97、2 72 .14±2 3 2 .74、40 .42± 3 4.76fmol/ 10 6 ,对照组 AT1 R和 AT2 R的 Bmax值左室为 2 9.2 0± 19.5 0和 2 .90± 0 .64 ,右室为76.72± 5 1.2 1和 9.63± 1.2 7fm ol/ L )增高明显 ( P<0 .0 5 )。结论 心内左向右所引起的心室容量负荷过重 ,导致AT1 R的表达增高 ,是 VSD心室肥厚及重构的重要机制 ;AT2 R在右心室表达增高 ,可能是中等程度容量负荷的VSD容易出现左室肥厚而非右室肥厚的原因 相似文献
18.
Yan Wang Xuesong Zhang Songhua Xiao Ning Lu Zheng Wang Mi Zhou 《Journal of orthopaedic surgery and research》2006,1(1):13-7
Objectives
To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively. 相似文献19.
本文用反复静脉注射小剂量牛血清白蛋白复制家兔慢性肾炎,用羊踯躅根治疗。同时,用该药对慢性肾炎病人进行疗效观察。阳性组兔肾小球呈现中至重度颗粒形免疫荧光,肾组织呈明显慢性硬化性肾小球肾炎改变。尿蛋白±~++。治疗组兔及病人治疗后病变及症状均明显减轻或消失。结果提示循环免疫复合物反复沉着可引起兔类似人类的慢性硬化性肾小球肾炎,羊踯躅根对病变有一定的控制和治疗作用,这可能与其抑制免疫发病机制有关。 相似文献
20.
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. To evaluate the immunomodulatory effect of MCPD on murine splenocyte and macrophage in vitro, we investigated splenocyte blastogenesis by concanavalin A (Con A), anti-CD3, and lipopolyssacharide (LPS), the production of cytokines from splenocyte, and the activity of mouse peritoneal macrophages. There was a significant decrease in lymphocyte blastogenesis to Con A or anti-CD3 at subtoxic dose of MCPD. A significant decrease in splenocyte blastogenesis to LPS was also observed. The production level of interferon (IFN)-gamma on splenocyte culture with Con A was significantly reduced at the higher concentration than 1.0mM of MCPD. The levels of interleukin (IL)-4 and IL-10 were also decreased at high concentrations of MCPD. There was a significant decrease in production of nitric oxide (NO) by peritoneal macrophages treated with MCPD. MCPD also inhibits tumor necrosis factor (TNF)-alpha production of stimulated macrophages. These results indicate that MCPD might be able to reduce the functionality of lymphocytes and peritoneal macrophages in vitro. 相似文献