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21.
Summary In crayfish, the severed distal segment of single lateral giant axon (SLGA) often survives for at least 10 months after lesioning if this segment retains a septal region of apposition with an adjacent, intact SLGA. In control (unsevered) SLGAs, this septal region usually contains gap junctions and 50–60 nm vesicles near the axolemma of both SLGAs. From 1–14 days after lesioning, the distal segment of a severed SLGA undergoes obvious ultrastructural changes in mitochondria and neurotubular organization compared to control SLGAs or to adjacent, intact SLGAs in the same animal. Gap junctions are very difficult to locate in severed SLGAs within 24 h after lesioning. From two weeks to ten months after lesioning, the surviving stumps of severed SLGAs often appear remarkably normal except that structures normally associated with the presence of gap junctions remain very difficult to find.These and other data suggest that SLGA distal segments receive trophic support from adjacent, intact SLGAs. The mechanism of this support probably could not be via diffusion across gap junctions between intact and severed SLGAs since gap junctions largely disappear after lesioning. However, trophic maintenance could occur via the exocytotic — pinocytotic action of 50–60 nm vesicles which are always present on both sides of the septum between an intact SLGA and a severed SLGA distal segment.This work was supported by NIH research grant NS-14412 and and RCDA 00070 to G.D.B.  相似文献   
22.
Fibrous dysplasia, characterized by benign osteolytic and osteoblastic lesions may involve one or several bones. Recent investigators have suggested that it may be merely a phase of what have previously been thought to be several different bone disease. Isolated fibrous dysplasia in the temporal bone is infrequent. Several reports of this disease have appeared in the literature of paleopathology, but none involved only the temporal bone. Monostotic involvement of the right temporal bone was discovered in the skull of an adult male recovered from an archeological site dating from the Late Mississippian period (A. D. 1,350–A. D. 1,650). It will provide an opportunity for preliminary documentation of the antiquity of this disease in the southeastern portion of the United States.  相似文献   
23.
摘要 目的:探讨人滋养细胞表面抗原(trophoblast cell-surface antigens2,Trop-2)在病变子宫内膜中的表达及其临床相关性。方法:采用免疫组化法检测100例正常子宫内膜或病变子宫内膜组织中Trop-2蛋白的表达,其中单纯增生子宫内膜患者26例,复杂或不典型增生子宫内膜患者34例,子宫内膜腺癌患者20例,对照组为20例增生期子宫内膜患者。结果:免疫组织化学法研究结果显示,Trop-2蛋白在正常增生子宫内膜和单纯性增生子宫内膜中几乎不表达,在复杂或不典型增生子宫内膜组织中以及子宫内膜腺癌呈阳性表达。主要分布在细胞膜上,阳性率分别为35.29 %和65.00 %,经过对比子宫内膜癌组的阳性表达率显著高于复杂型或伴不典型增生子宫内膜组的阳性表达率(P<0.05),且复杂型或伴不典型增生子宫内膜组的阳性表达率显著高于单纯性增生子宫内膜组(P<0.05),其表达水平随内膜病变程度的加重而升高,呈正相关关系(P<0.05)。结论:Trop-2蛋白在子宫内膜病变中的表达与其严重程度一致,可反映子宫内膜病变的发生发展,或可作为判断其严重程度的指标。  相似文献   
24.
25.
目的分析肺炎支原体感染对川崎病的影响及其机制,以期指导临床诊疗。方法回顾性分析2013年8月至2018年8月我科住院的496例川崎病患儿临床资料,其中合并肺炎支原体感染组193例,未合并肺炎支原体感染组303例。应用倾向评分匹配法1∶1校正2组的年龄、性别、是否为不完全型川崎病、是否使用糖皮质激素、丙种球蛋白使用时间、丙种球蛋白使用方法和阿司匹林初始剂量,比较2组患儿的总发热天数、冠状动脉直径、冠状动脉扩张发生率、冠状动脉瘤发生率和丙种球蛋白无反应发生率。结果川崎病合并肺炎支原体感染组男性患儿多,更易发生颈部淋巴结肿大,年龄、中性粒细胞百分比、血沉和低密度脂蛋白高于川崎病未合并肺炎支原体感染组,血钾、血钙、高密度脂蛋白和白蛋白低于川崎病未合并肺炎支原体感染组,差异有统计学意义(均P<0.05)。应用倾向评分匹配法1∶1配对后发现,川崎病合并肺炎支原体感染组患儿总发热时间更长[8(6~10)d vs 7(6~9)d,Z=-2.089,P<0.05),冠状动脉直径值更大[(2.81±0.81)mm vs(2.63±0.45)mm,t=2.532,P<0.05],冠状动脉瘤发生率更高(5.5% vs 1.1%,χ2=5.516,P<0.05)。结论肺炎支原体感染可能引起川崎病患儿脂质代谢及电解质的紊乱,其炎症反应更强,持续时间更长,对冠状动脉损伤更大。  相似文献   
26.
目的:对不同胃癌前病变中医证型和血清胃蛋白酶原(pepsinogen,PG)、胃泌素-17(gastrin-17,G-17)、癌胚抗原(carcinoembryonic antigen,CEA)和叶酸水平变化的关系进行探讨,为胃癌前病变的诊断提供一定的依据。方法:以80例胃癌前病变(precancerous lesion of gastric cancer,PLGC)患者研究组,80例健康者为对照组,对研究组患者进行中医临床辨证分型,对两组研究对象的血清PG、G-17、CEA和叶酸进行测定比较。结果:研究组PLGC患者中医证型分布不均匀,差异显著(P<0.05),由多到少依次为湿热蕴胃并/兼脾胃虚寒证>胃络瘀阻并/兼气阴两虚证>痰湿中阻并/兼脾胃气虚证>肝胃气滞并/兼气阴两虚证>肝胃气滞并/兼脾胃虚寒证>湿热蕴胃并/兼胃阴不足证。PLGC不同中医证型患者血清PG I和PG II水平差异显著(P<0.05);与对照组比较,各证型PG I水平均显著降低,PG II水平均显著升高(P<0.05)。且湿热蕴胃并/兼脾胃虚寒证和胃络瘀阻并/兼气阴两虚证的PG I水平显著低于其他证候,血清PG II水平显著高于其他(P<0.05)。与对照组比较,研究组不同证候的G-17、CEA水平显著升高,叶酸水平显著降低(P<0.05);观察组中湿热蕴胃并/兼脾胃虚寒证和胃络瘀阻并/兼气阴两虚证G-17、CEA显著高于其他证候,叶酸水平显著低于其他证候(P<0.05)。结论:胃癌前病变不同中医证型血清PG、G-17、CEA和叶酸存在明显差异。  相似文献   
27.
目的探究阴道微生态与高危型人乳头瘤病毒(HR-HPV)感染以及宫颈病变之间的相关性,为后续研究提供参考。方法选择2018年1月至2019年6月就诊于石河子大学医学院第一附属医院妇科门诊,同时行爱必维(细菌性阴道病五项联合测定试剂盒)检测、HR-HPV检测及宫颈组织病理检查的343名妇女作为研究对象,分析相关检测数据并探究阴道微生态与HR-HPV感染以及宫颈病变的相关性。结果过氧化氢阳性、唾液酸苷酶阳性、白细胞酯酶阳性、乳杆菌数量减少及阴道清洁度3~4度的妇女感染HR-HPV及发生宫颈病变的可能性显著大于过氧化氢阴性、唾液酸苷酶阴性、白细胞酯酶阴性、乳杆菌数量较多及阴道清洁度1~2度的妇女,差异均有统计学意义(均P0.05)。经多因素Logistic回归分析发现,过氧化氢、唾液酸苷酶、白细胞酯酶及阴道清洁度3~4度均为影响宫颈病变的危险因素(均P0.05)。结论阴道微生态失衡与HR-HPV感染以及宫颈病变有一定关联,纠正阴道微生态失衡可一定程度上预防HR-HPV感染及宫颈病变。  相似文献   
28.
目的:探讨2型糖尿病(T2DM)患者血糖波动与心律失常和下肢血管病变的关系,分析影响T2DM心律失常和下肢血管病变的因素。方法:选择2019年7月到2020年6月我院收治的82例T2DM患者,根据是否合并心律失常分为心律失常组28例和无心律失常组54例,根据是否合并下肢血管病变分为下肢血管病变组31例和无下肢血管病变组51例。所有患者均通过72 h监测血糖获得日内平均血糖波动幅度(MAGE)、日间血糖平均绝对差(MODD)、全天血糖标准差(SDBG)、全天血糖波动次数(NGE)。比较组间差异,分析影响T2DM患者心律失常和下肢血管病变的因素。结果:心律失常组MAGE、MODD、SDBG、NGE、糖化血红蛋白(HbA1c)、胰岛素抵抗指数(HOMA-IR)、T2DM病程、同型半胱氨酸(Hcy)、丙二醛(MDA)高于无心律失常组(P<0.05)。下肢血管病变组T2DM病程、Hcy、MDA、HOMA-IR、MAGE、MODD、SDBG、NGE均高于无下肢血管病变组(P<0.05)。Logistic回归分析结果显示MDA、HOMA-IR、MAGE、MODD是T2DM患者心律失常的危险因素(P<0.001),MAGE、MODD、SDBG是T2DM患者下肢血管病变的危险因素(P<0.001)。结论:T2DM患者血糖波动与心律失常和下肢血管病变均有关,血糖波动增加是T2DM心律失常和下肢血管病变的危险因素。  相似文献   
29.
Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN.  相似文献   
30.
Muscle loss is a major problem for many in lifetime. Muscle and bone degeneration has also been observed in individuals exposed to microgravity and in unloading conditions. C2C12 myoblst cells are able to form myotubes, and myofibers and these cells have been employed for muscle regeneration purposes and in myogenic regeneration and transplantation studies. We exposed C2C12 cells in an random position machine to simulate microgravity and study the energy and the biochemical challenges associated with this treatment. Simulated microgravity exposed C2C12 cells maintain positive proliferation indices and delay the differentiation process for several days. On the other hand this treatment significantly alters many of the biochemical and the metabolic characteristics of the cell cultures including calcium homeostasis. Recent data have shown that these perturbations are due to the inhibition of the ryanodine receptors on the membranes of intracellular calcium stores. We were able to reverse this perturbations treating cells with thapsigargin which prevents the segregation of intracellular calcium ions in the mitochondria and in the sarco/endoplasmic reticula. Calcium homeostasis appear a key target of microgravity exposure. In conclusion, in this study we reported some of the effects induced by the exposure of C2C12 cell cultures to simulated microgravity. The promising information obtained is of fundamental importance in the hope to employ this protocol in the field of regenerative medicine  相似文献   
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