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961.
962.
963.
The protein kinase Chk1 is required for cell cycle arrest in response to DNA damage. We have found that the 14-3-3 proteins Rad24 and Rad25 physically interact with Chk1 in fission yeast. Association of Chk1 with 14-3-3 proteins is stimulated in response to DNA damage. DNA damage results in phosphorylation of Chk1 and the 14-3-3 proteins bind preferentially to the phosphorylated form. Genetic analysis has independently implicated both Rad24 and Rad25 in the DNA-damage checkpoint pathway. We suggest that DNA damage-dependent association of phosphorylated Chk1 with 14-3-3 proteins mediates an important step along the DNA-damage checkpoint pathway, perhaps by directing Chk1 to a particular substrate or to a particular location within the cell. An additional role for 14-3-3 proteins in the DNA-damage checkpoint has been suggested based on the observation that human Chk1 can phosphorylate Cdc25C in vitro creating a 14-3-3 binding site. Our results suggest that in fission yeast the interaction between the 14-3-3 proteins and Cdc25 does not require Chk1 function and is unaffected by DNA damage, in sharp contrast to the interaction between the 14-3-3 proteins and Chk1.  相似文献   
964.
The epithelium in kidneys and urinary bladders contain CK18 as in liver cells. The modulation of cytokeratin 18 during tumor transformation in hepatoma had been previously recognized through a series of biochemical and immunological approaches. A 14 KD hepatoma related molecules was found in the previous studies. We would like to utilize the hepatoma transformation model to study the changes in CK18 in transitional cell carcinoma, using immunoblotting and western blotting techniques. The result is that transitional cell carcinoma retain their CK18 molecule. Furthermore, CK18 related molecules similar to those seen in hepatoma also present in transitional cell carcinoma. The conclusions are transitional cell carcinoma contains CK18 related proteins similar to those seen in hepatoma tissues. We suggest that this element would be responsible for the change during the malignant transformation processes.  相似文献   
965.
The IFN-gamma produced by Th1 cells and IL-4 produced by Th2 cells are two most important cytokines in the regulation of IgE production. House dust immunotherapy has been tried in the treatment of house dust-sensitive Chinese asthmatic patients with good results. We examined the influence of such treatment on in vitro IL-4 and IFN-gamma production by peripheral blood mononuclear cells in house dust-sensitive asthmatic patients. Allergen immunotherapy in house-dust sensitive asthmatic patients can significantly decrease IL-4 production from peripheral mononuclear cells (p<0.05). The production levels of IL-4 in patients without treatment had higher levels than those in patients with hyposensitization (p<0.01). Such therapy also have some effect on promotion of IFN-gamma production in asthmatic patients. In conclusion, immunotherapy with house dust may have the potential ability to shift the Th1/Th2 balance of immune response to allergens and to create a favorable cytokine microenvironment to suppress the allergic reaction in the asthmatic airway.  相似文献   
966.
In patients with agenesis of the vagina and cervix but with a functional endometrium, the traditional treatment is hysterectomy with construction of a neovagina. We report successful treatment by laparoscopically assisted full thickness skin graft for reconstruction in a patient with congenital agenesis of the vagina and uterine cervix concomitant with haematometra and ovarian endometrioma in a 12 year old girl. Postoperatively, the vaginal skin graft healed well, and menstruation first appeared 4 weeks later. In our opinion, a combined laparoscopic and vaginal procedure with full thickness skin graft is an efficacious alternative in managing such genital defects.  相似文献   
967.
本报告了依拉地平(isradipine)治疗30例原发性高血压的临床效果及安全性。观察期限6周,结果显示依拉地平1.25mg,每日2次,有14例病人获得满意的疗效,卧位血压由165.5±3.2/100.9±2.9mmHg降至146.1±1.2/89.1±2.5mmHg。11例病人服用剂量增至2.5mg,每日2次,卧位血压降至148.6±4.1/91.5±2.2mmHg。3例加服马来酸依那普利10mg,每日2次,血压降至152.5±2.3/94.9±5.6mmHg。2例病人降压效果不明显。单用依拉地平治疗高血压总有效率为83.3%,副作用较少,并随用药时间的延长而消失。  相似文献   
968.
目的 :用化学发光法检测O2 、CO2 、CO和正庚烷 (CxHy)四种气体对离体家兔肺泡巨噬细胞 (AM )的直接效应。 方法 :将AM悬液暴露于上述气体 ,不同时间检测用PMA激发的细胞发光及其存活率。结果 :培养在 99.5 %N2 (0 .5 %O2 )中的AM受激发光仅能维持 10h ;高浓度O2 、CO2 、CO和CxHy具有刺激或增强AM发光之效应 ;含 16 %O2 、1.9%CO2 、46mg/m3 CO和 176mg/m3 CxHy的模拟潜艇混合气体未见对AM激发光功能和存活率产生不利影响。结论 :空气氧含量对细胞十分重要 ,提高氧浓度有利于细胞存活 ,但氧浓度 >16 %和 <2 0 %的低氧还原性气体环境更有利细胞长时间生存。  相似文献   
969.
目的:研究糖尿病患者血浆纤维蛋白原水平与功能。方法:用蕲蛇酶(Acutulase)水解纤维蛋白,用计算机自动检测系统测定。结果:1.无并发症糖尿病病人20例,FMPV:0.579 ± 0.130,Amax:0.297±0.060,S:3.100±0.850(g/L),FMPV/Amax:1.957±0.17O,DT:15±5 s;2.有并发症(高血压、糖尿病性肾病等)糖尿病病人20例,FMPV:0.847±0.190,AmaX:0.406± 0.090,S:4.970 ±0.950(g/L),FMP/Amax:2.067±0.190,DT:9±3 s。结论:糖尿病患者的纤维蛋白原水平与功能高于健康成人,有并发症者尤甚,表明糖尿病患者存在高凝状态,纤维蛋白原水平增高与功能亢进为并发血管病变及血栓形成的重要因素。  相似文献   
970.
目的:探讨闭角型青光眼患者凝血指标变化与临床的关系。方法:对50例闭角型青光眼患者及43例正常对照组进行了凝血指标(PT、TT、Fbg、APTT)检测。结果:闭角型青光眼患者与对照组比较PT、TT无显著变化(P<0.05),Fbg含量升高有极显著性差异(P<0.01),APTT时间缩短有极显著性差异(P<0.01)。结论:闭角型青年眼患者体内血液是高凝状态,而这种高凝状态在闭角青光眼病的发生、发展中起着重要的作用。  相似文献   
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