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111.
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc.  相似文献   
112.
125~I-后标记法是庄志雄等人(1994)提出的一种检测DNA-蛋白质交联物(DPCs)的新技术,该法在检测离体CHO细胞DPCs的实验中已显示出敏感、快速和简便的优点。本研究表明,125~I-后标记法不仅能有效地检出由紫外光和铬酸钾诱导的CHL细胞DPCs,并能有效而敏感地检测由铬酸钾和氯化镍引起的大鼠不同组织特别是白细胞DPCs形成的情况,是一种敏感的和可考虑应用于人群调查的DPCs检测方法。  相似文献   
113.
Iodine-125 interstitial irradiation for cerebral gliomas   总被引:3,自引:0,他引:3  
  相似文献   
114.
Exposure of H69 small cell lung carcinoma cells to nicotinic agonists resulted in a significant increase (up to 100%) in cell number after 6 to 12 days. The effect of nicotine (10−8 M to 10−4 M) was both dose and time dependent as was that of another nicotinic agonist cytisine (10−6 M to 10−4 M). Interstingly, both the nicotine and cytisine induced increases in H69 cell number were blocked by α-bungarotoxin, as well as d-tubocurarine a nicotinic blocker which appears to interact with most nicotinic receptors. These results suggest that the nicotine induced increase in cell number is mediated through an interaction at the nicotinic α-bungarotoxin receptor. This idea is further supported by experiments which show (1) that H69 cells possess high affinity α-bungarotoxin sites (Kd = 25 nM, Bmax = 10.4 fmol/106 cells) with the characteristics of a nicotinic α-bungarotoxin receptor and (2) that the potencies of nicotinic receptor ligands in the α-bungarotoxin binding assay were similar to those observed in the functional studies. Northern analysis showed that mRNA for α7, a putative nicotinic α-bungarotoxin binding subunit, and for α5 were present in H69 cells. The present data provide further evidence that nicotine increases cell number in small cell lung carcinoma and are the first to show that this effect is mediated through an interaction at the nicotinic α-bungarotoxin receptor population. These results suggest that the α-bungarotoxin site may be involved in modulating proliferative responses in neuroendocrine derived SCLC cells.  相似文献   
115.
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   
116.
Liposomes as drug carriers in cancer chemotherapy have attracted considerable interest. To enhance the therapeutic effect of Adriamycin entrapped in liposomes (Lip-ADM) on human solid tumors, we investigated the therapeutic effects of Lip-ADM in combination with recombinant human tumor necrosis factor-alpha (rTNF-alpha), which is known to have specific effects on tumor vasculature. rTNF-alpha or saline solution was injected intravenously into nude mice bearing a human colon cancer strain, HC-1, at 1 hour before intravenous administration of Lip-ADM. The significant therapeutic effect of Lip-ADM in combination with rTNF-alpha was demonstrated by the evaluation with tumor growth curve and the actual tumor weights, in comparison with groups of mice treated with saline solution, rTNF-alpha alone, or with a Lip-ADM after saline. Levels of Adriamycin in tumor tissue in the Lip-ADM in combination with rTNF-alpha-treated group were higher than those in Lip-ADM with saline solution-treated group.  相似文献   
117.
118.
125I粒子组织间种植对人胃癌裸鼠移植瘤的杀伤作用   总被引:8,自引:3,他引:5  
目的 观察不同剂量^125I粒子对人胃癌裸鼠移植瘤的杀伤作用及组织损伤。方法 建立人胃癌BGC-823细胞裸鼠皮下移植瘤模型,随机分为对照组和实验组,将不同剂量(100、120、140Gy)地^125I粒子植于实验组。30、60d:比较移植瘤抑瘤率,病理组织学、局部皮肤反应、裸鼠体重及白细胞计数。结果30d,100、120、140Gy组抑瘤率分别为51.93%、79.18%、90.22%,病理组织学反应程度多为RCRG2(45.83%),各实验组组间除120Gy与140Gy(P〉O.05)组外,及分别与对照组比较,差异有统计学意义(P〈0.05);局部皮肤反应各实验组与对照组比较,差异有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05)。60d,各组抑瘤率分别为97.97%、100%、96.69%,病理组织学反应程度以RCRG1居多(62.5%),与对照组比较,差异均有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05);局部皮肤反应随剂量增高而加重,各实验组组间及其分别与对照组比较,差异有统计学意义(P〈0.05)。结论 不同剂量的^125I粒子在不同时间对人胃癌裸鼠皮下移植瘤有显著杀伤作用,但120Gy和140Gy组随剂量累积,损伤明显增加。提示100Gy可能是治疗人胃癌裸鼠皮下移植瘤的有效剂量。  相似文献   
119.
Abstract.   Jaaback KS, Ludeman L, Clayton NL, Hirschowitz L. Primary peritoneal carcinoma in a UK cancer center: comparison with advanced ovarian carcinoma over a 5-year period. Int J Gynecol Cancer 2006; 16(Suppl. 1): 123–128.
The relative incidence of primary peritoneal carcinoma (PPCa) and advanced (FIGO stage III or IV) ovarian serous carcinoma (AOSCa) was assessed over 5 years at a UK cancer center, and the sociodemographic, clinical, and survival data were compared. There were 23 women with PPCa and 55 with AOSCa. The ratio of PPCa:AOSCa was higher than previously reported. No statistical difference was found between the two groups with regard to age (mean 64.43 vs 64.07 years, P = 0.9), parity (1.6 vs 1.8, P = 1.0), personal/family history of another malignancy (although five patients with AOSCa but none with PPCa had personal histories of breast cancer), or serum CA125, CA19.9, and carcinoembryonic antigen (CEA) levels. Similar numbers in both groups had malignant ascites, although 5.8% of patients with AOSCa but none with PPCa had negative cytology. Tumor grade, stage, treatment, and survival were similar (median 586 vs 641 days, P = 0.66). This analysis of the largest published UK series of patients with PPCa does not support previous reports that patients with PPCa are older than those with AOSCa and have a worse prognosis; it suggests that both groups have similar sociodemographic characteristics, clinical profiles, and survival.  相似文献   
120.
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