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121.
紫丁香叶提取物对HepG2.2.15细胞中HBeAg及HBsAg表达的影响   总被引:3,自引:0,他引:3  
目的 :观察紫丁香叶提取物对 Hep G2 .2 .1 5细胞分泌 HBe Ag和 HBs Ag的影响。方法 :采用酶联免疫吸附法 ( ELISA)检测培养上清中 HBe Ag和 HBs Ag表达的变化并以抑制率来表示。结果 :紫丁香叶提取物对 HBe Ag和 HBs Ag的分泌具有抑制作用 ,该作用呈现剂量依赖性和时间依赖性。结论 :紫丁香叶提取物对 HBe Ag和 HBs Ag分泌的抑制作用提示其在体外具有抗乙型肝炎病毒的作用  相似文献   
122.
In primates, corpus luteum development involves both gonadotrophin stimulation and exposure to low density lipoprotein (LDL) delivered through vascularization of the granulosa cell-derived layer. These regulatory influences were modelled in vitro using granulosa cells obtained during in-vitro fertilization (IVF) cycles controlled with gonadotrophin releasing hormone (GnRH) analogue, human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG). Granulosa cells were cultured in defined medium on extracellular matrix. Without gonadotrophin or LDL in the medium, progesterone production declined progressively. With LDL alone, there was a short-lived elevation of progesterone output which subsequently declined. Culture with HCG alone resulted in a relatively unchanged rate of steroid production over 5 days despite morphological development. This contrasted with a marked and sustained increase in progesterone output over the same time when granulosa cells were cultured with combined HCG/LDL. Cultures were challenged with combined HCG/LDL on day 5. Where initial incubation included HCG, the challenge resulted in a recovery of progesterone output to values comparable to those of granulosa cells exposed to continuous HCG/LDL. Initial incubation without gonadotrophin led to a reduced response. Results suggest that LDL delivery to granulosa cells of the early corpus luteum causes a short-lived period of progesterone production. Sustained luteinization of granulosa cells and maintenance of gonadotrophin responsiveness requires continued exposure to gonadotrophin in the luteal phase.  相似文献   
123.
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported.  相似文献   
124.
大鼠壁细胞的黏膜刮取式分离方法   总被引:1,自引:1,他引:0  
采用黏膜刮取式方法,分离大鼠胃黏膜细胞。用相差显微镜、HE染色、电镜、荧光显微镜、免疫细胞化学染色等方法,对壁细胞进行观察和鉴定,并测定了壁细胞直径。结果成功地分离了大鼠胃黏膜细胞,同时证实,壁细胞在所分离的细胞中直径最大。  相似文献   
125.
Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP.  相似文献   
126.
目的总结1例异基因造血干细胞移植后并发与慢性移植物抗宿主病(cGVHD)相关的多发性肌炎的诊治体会。方法1例急性淋巴细胞白血病患者在处于完全缓解状态下接受同胞间供髓异基因造血干细胞移植,移植后采用环孢素A和甲氨蝶呤预防移植物抗宿主病(GVHD)。结果移植后11 d,WBC>0.5×10~9/L,移植后13 d,血小板>20×10~9/L;27 d时,骨髓细胞染色体分析显示99%为供者型。移植后17 d,发生Ⅰ度急性皮肤型GVHD,经静脉注射地塞米松及甲氨蝶呤后,GVHD被完全控制。移植后8个月,患者发生轻度肝脏cGVHD,经他克莫司及硫唑嘌呤治疗,效果不佳,血清肝酶升高,后改为他克莫司和西罗莫司治疗,血清肝酶逐渐下降,但肌酸激酶从9 U/L上升至272 U/L,随后患者出现全身乏力,并逐渐加重,上下肢近端处活动出现障碍,肌酸激酶升至3010 U/L,股四头肌、肱二头肌的肌电图表现为肌源性损害,双侧大腿磁共振成像符合多发性肌炎表现,给予甲泼尼龙、血浆置换治疗,但无显著效果,患者突发阵发性呼吸困难,经抢救无效,患者死亡,死亡时肌酸激酶为21 010 U/L。结论多发性肌炎为cGVHD的一种较少见形式,累及重要肌组织者预后较差。  相似文献   
127.
BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
128.
HSV-2 W株感染Vero细胞后,对细胞的分裂指数可产生以下影响:在一定作用时间内,接种病毒的细胞其分裂指数高于对照细胞而低于接种秋水仙素的细胞;接种病毒最多的细胞高于接种病毒量少的细胞;但超过一定时间,则差别不显著;接种病毒时间长的细胞低于接种病毒时间短的细胞;接种灭活病毒的细胞高于接种未来灭活病毒的细胞。根据以上结果就HSV-2对宿主的某些生物学作用讲行了讨论。  相似文献   
129.
Summary After orthotopic rat liver transplantation in the fully allogeneic BN (RT-1n) to LEW (RT-11) combination, the phenomenon of spontaneous tolerance of donor antigen occurs. We demonstrate two different immune mechanisms that may account for this process. Using adoptive transfer assays we show the presence of donor-specific T-suppressor lymphocytes in the spleens of long-term surviving liver graft, recipients. These cells prolong - adoptively transferred into irradiated syngeneic hosts — the survival of donor-specific (BN) but not third-party (DA) renal allografts (I00 days vs 1I days in control groups). Secondly, we demonstrate the replacement of Kupffer cells in the graft by recipient macrophages using polymorphic monoclonal antibodies in an immunoperoxidase technique. This may contribute to graft adaptation and thus to long-term graft acceptance.  相似文献   
130.
新生大鼠海马神经细胞原代培养方法的改良   总被引:7,自引:1,他引:6  
(1)目的:建立较理想的新生大鼠海马神经细胞体外原代培养方法。(2)方法:采用低浓度,长时间胰酶消化和机械分离相结合的方法进行单层原代培养。(3)结果:在体外培养条件下神经细胞结构特征明显化,并能形成典型的神经细胞网络。(4)结论;该培养技术是海马神经细胞体外培养的理想方法。  相似文献   
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