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41.
用放射配体结合分析法分别测定了正常组、特布他林组、特布他林十曲尼司特组豚鼠的肺组织β受体最大结合力和解离常数,结果显示:给特布他林后豚鼠肺组织β受体发生明显的向下调节.曲尼司特可预防此向下调节的发生.  相似文献   
42.
M Y Fan  Z P Lum  X W Fu  L Levesque  I T Tai  A M Sun 《Diabetes》1990,39(4):519-522
Prolonged survival of pancreatic islet allografts implanted in diabetic BB rats was achieved by encapsulation of individual islets in a protective biocompatible alginate-polylysine-alginate membrane without immunosuppression. Intraperitoneal transplantation of the encapsulated islets reversed the diabetic state of the recipients within 3 days and maintained normoglycemia for 190 days. Normal body weight and urine volume were maintained during this period, and no cataracts were detected in the transplant recipients. In contrast, control rats receiving transplants of unencapsulated islets experienced normoglycemia for less than 2 wk. These results demonstrated that microencapsulation can protect allografted islets from both graft rejection and autoimmune destruction without immunosuppression in an animal model that mimics human insulin-dependent diabetes.  相似文献   
43.
复方华蟾胶囊抗小鼠肿中瘤作用的实验研究   总被引:2,自引:0,他引:2  
目的了解复方华蟾胶囊抗小鼠移植性肿瘤的作用.方法以小鼠肝癌22(H22)、小鼠肉瘤180(S180)为瘤株,应用动物移植性肿瘤的体内试验法对药物进行抗癌药效学试验.结果复方华蟾胶囊灌胃4,2 g/kg@d,连续14 d,对小鼠移植性肝癌实体型生长有明显的抑制作用,抑瘤率分别为38.09%,30.95%.对小鼠移植性S180实体型生长有明显的抑制作用,抑瘤率分别为34.7%,30.08%.复方华蟾胶囊对荷瘤小鼠的胸腺和脾脏重量无影响.结论复方华蟾胶囊在试验条件下有一定抗肿瘤作用.  相似文献   
44.
5339例创伤患者创伤及死亡特点分析   总被引:2,自引:0,他引:2  
目的 探讨创伤患者创伤及死亡特点。方法 回顾性分析 1996年 1月至 2 0 0 0年 12月我院收治 5 3 3 9例创伤患者的临床资料。结果  5 3 3 9例创伤患者中男性 3 910例 ,女性 14 2 9例 ,平均受伤年龄 (3 5 3± 3 3 7)岁 ,2 0~ 2 9岁占 64 19%。治愈好转5 168例 ,死亡 47例 ,3 1例死于重型、特重型颅脑损伤。结论 创伤的高危人群为青壮年 ,且男性多于女性 ,交通事故是本组创伤的第一位原因。把创伤的预防与控制作为一项政府工程 ,加强宣传和教育 ,改善交通状况等均对创伤的预防与控制有重要意义  相似文献   
45.
The mechanism by which mechanical strain and estrogen stimulate bone cell proliferation was investigated using monolayer cultures of human osteoblastic TE85 cells and female human primary (first-passage) osteoblasts (fHOBs). Both cell types showed small but statistically significant dose-dependent increases in [3H]thymidine incorporation in response to 17beta-estradiol and to a single 10-minute period of uniaxial cyclic strain (1 Hz). In both cell types, the peak response to 17beta-estradiol occurred at 10(-8) - 10(-7) M and the peak response to strain occurred at 3500 microstrain ((mu)epsilon). Both strain-related and 17beta-estradiol-related increases in [3H]thymidine incorporation were abolished by the estrogen receptor (ER) modulator ICI 182,780 (10-8 M). Tamoxifen (10(-9) - 10(-8) M) increased [3H]thymidine incorporation in both cell types but had no effect on their response to strain. In TE85 cells, tamoxifen reduced the increase in [3H]thymidine incorporation associated with 17beta-estradiol to that of tamoxifen alone but had no such effect in fHOBs. In TE85 cells, strain increased medium concentrations of insulin-like growth factor (IGF) II but not IGF-I, whereas 17beta-estradiol increased medium concentrations of IGF-I but not IGF-II. Neutralizing monoclonal antibody (MNAb) to IGF-I (3 microg/ml) blocked the effects of 17beta-estradiol and exogenous truncated IGF-I (tIGF-I; 50 ng/ml) but not those of strain or tIGF-II (50 ng/ml). Neutralizing antibody to IGF-II (3 microg/ml) blocked the effects of strain and tIGF-II but not those of 17beta-estradiol or tIGF-I. MAb aIR-3 (100 ng/ml) to the IGF-I receptor blocked the effects on [3H]thymidine incorporation of strain, tIGF-II, 17beta-estradiol, and tIGF-I. HOBs and TE85 cells, act similarly to rat primary osteoblasts and ROS 17/2.8 cells in their dose-related proliferative responses to strain and 17beta-estradiol, both of which can be blocked by the ER modulator ICI 182,780. In TE85 cells (as in rat primaries and ROS 17/2.8 cells), the response to 17beta-estradiol is mediated by IGF-I, and the response to strain is mediated by IGF-II. Human cells differ from rat cells in that tamoxifen does not block their response to strain and reduces the response to 17beta-estradiol in TE85s but not primaries. In both human cell types (unlike rat cells) the effects of strain and IGF-II as well as estradiol and IGF-I can be blocked at the IGF-I receptor.  相似文献   
46.
HCC的早期诊断是其治疗的关键,HCC血清标志物的检测又为其诊断提供了有利的途径,并且操作简单,敏感性高和特异性强。目前常用的血清标志物为AFP、AFP变异体、AFP mRNA、AFU、GGT、DCP、AIF、GPC3等。这些标志物的联合使用有助于HCC的诊断及预后。  相似文献   
47.
张钧  李鸣  李平 《西南国防医药》2007,17(4):420-422
目的:探讨甲状腺全切除术在治疗分化性甲状腺癌中的临床应用价值。方法:采用我院1988年1月~2001年5月甲状腺全切除术或甲状腺侧叶切除加峡部切除术治疗分化性甲状腺癌125例,对其手术并发症发生、局部复发、转移情况及术后5年生存率进行回顾性对比分析。结果:甲状腺全切除术术后并发症发生率高于甲状腺侧叶切除加峡部切除术组;局部复发、转移率低于侧叶切除加峡部切除术组;5年生存率两组无显著性差异。结论:甲状腺全切除术是治疗甲状腺癌有效的手术方式,但应掌握手术指征,改进、提高手术技术,减少并发症。  相似文献   
48.
Objective To test the hypothesis that p53 gene therapy combined with endostatin can enhance tumor response to radiation therapy of RM-1 mouse xenograft prostate cancer and to investigate its mechanism. Methods A mouse prostate cancer model was established. Then mice with xenograft tumor were randomly divided into group A (control), B (radiation), C (radiation and rAdp53), D (radiation and rh-endostatin) and E (radiation and rAdp53 and rh-endostatin). On day 1, rAdp53 was injected intra-tumorously with 1 × 1010 vp per animal to group C and E. From day 1 to 14, rh-endostatin was given 15 mg/kg intraperitoneally daily to group D and E. On day 4 single fraction of 15 Gy was given to tumors in groups B, C, D and E. Normal saline was injected intra-tumorously or intraperitoneaUy accordingly as control. No treatment was done to group A. Tumor volume was measured daily. Samples were collected on Days 5, 10 and 15. Ki67, CD31, p53 and VEGF were detected by means of immunohistochemistry. Results (1) Radiation alone, radiation combined with intra-tumorous injection of Adp53 and/or intraperitoneal injection of rh-endostatin resulted in tumor growth arrest of RM-1 cells in vivo (P = 0.000). Radiation combined with both rAdp53 and rh-endostatin was the most effective treatment (P < 0.05). (2) All the four treatment groups had a decreased expression of mutant type P53 (P = 0.000). The expression of Ki67 in groups B and C were equal (P 0.05) and increasing (P = 0.000), respectively. Group D had a up-down-up curve (P < 0.05), but group E had a up-down one. On day 5 the expresion of VEGF in group E was the lowest (P < 0.05). An increased expression of MVD compared with the control was shown, and MVD in groups C, D and E were always higher than that in the control (P < 0.05). Conclusions The limitation of radiotherapy could be overcome by combination with beth p53 gene therapy and endostatin on the growth of mouse prostate cancer cell. Radiation, rAdp53 and endostatin have their own role but they can be interacted with each other.  相似文献   
49.
氟尿嘧啶化放疗的现状与未来   总被引:1,自引:0,他引:1  
赵明 《药品评价》2006,3(4):252-263,270
20世纪60年代在肿瘤的根治和辅助治疗中就使用了氟尿嘧啶(Fluorouracil,FU)化放疗(外放疗同时进行化疗)。2002年.全世界约200万肿瘤患者接受了FU治疗.其中很大一部分是以FU为基础的化放疗。FU是许多肿瘤患者的基础治疗药物。总之,FU化放疗显著改善了肿瘤的局部控制.并提高了部分肿瘤患者的生存率:也提高了部分具有重要功能的器官的保留。  相似文献   
50.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
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