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71.
72.
目的:观察天然骨缝牵张成骨过程中组织和细胞超微结构的变化。方法:对牵张成骨的缝区组织经过系列处理,进行超薄切片、透射电镜观察。结果:间充质细胞在牵引早期大量增生,并不断分化为成纤维细胞和成骨细胞,后2种细胞的超微结构显示出具有活跃的合成和分泌功能。1周标本成纤维细胞沿牵引力的长轴方向排列,胞核增大,在其周围包绕着发达并扩张的内质网系统;3周标本大量增生活跃的成骨细胞和成纤维细胞,成骨细胞核仁增大、粗面内质网扩张、核糖体丰富、线粒体增多、富含紧密排列的嵴;5、8周标本中骨细胞形成并发育成熟,骨基质逐渐矿化,清晰可见新形成的胶原纤维、哈氏管,以及骨基质矿化的过程。结论:三维牵张过程中,成纤维细胞、成骨细胞活跃,缝区形成新骨。 相似文献
73.
目的 探讨瘢痕子宫使用双球囊导管促宫颈成熟及引产后阴道分娩的安全性和有效性.方法 以2016年1月—2018年7月本院收治有阴道分娩条件和意愿的59例宫颈未成熟的足月瘢痕子宫作为研究组,以同期分娩的67例足月非瘢痕子宫宫颈未成熟的为对照组,两组均使用双球囊导管促宫颈成熟及引产,比较两组的母婴结局.结果 研究组孕产妇的年... 相似文献
74.
The purpose of this work was to study the possibility of neutralizing high-calcium fly ash expansion during hydration. The object of the study was the fly ash of Berezovskaya GRES, which is capable of independent setting and hardening. The test in the Le Chatelier molds showed that the divergence of indicator arms was 90–100 mm 1 day after mixing with water. The expansion and cracking of the fly ash could be completely prevented by silica fume addition in an amount of 42.9% by weight of the fly ash. At the same time, the compressive strength of specimens from the fly ash–sand paste in a ratio of 1:5 at the age of 28 days was 1.47 MPa. The isothermal heat release at a temperature of 20 °C for 10 days reached 500 kJ/kg. XRF and DTA results showed that free lime in the fly ash was completely hydrated in 11 days and gave the greatest expansion in the absence of silica fume. The presence of silica fume made the lime hydration incomplete and decreased the expansion. Unslaked free lime remained in the system. Exothermic data showed that silica fume inhibited CaO hydration from the reaction start. 相似文献
75.
Safeer Abbas Ali Ahmed Ayesha Waheed Wasim Abbass Muhammad Yousaf Sbahat Shaukat Hisham Alabduljabbar Youssef Ahmed Awad 《Materials》2022,15(10)
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion. 相似文献
76.
观察与评价“整颈三步九法”在新疆地区治疗风寒阻络型颈椎病的临床疗效。方法:门诊纳入240例风寒阻络型颈椎病的患者,男女性别不限,随机分为试验组和对照组,每组120例。试验组采用“整颈三步九法”进行治疗,对照组采用“常规推拿手法”治疗,两组均每天治疗1次,共治疗14次。两种手法操作由四名推拿专业副主任医师来完成。观察两组患者的中医证候、疼痛(MPQ疼痛评估量表)的改善情况以及临床疗效。结果:试验组与对照组总有效率分别为93.16%与84.03%,临床疗效组间比较有统计学差异(P<0.05);两组患者治疗后的疼痛与中医证候积分与治疗前比较有一定改善(P<0.05,P<0.01)。结论:改进后的“整颈三步九法”治疗风寒阻络型颈椎病较以往的手法更具有有效性和安全性,而且操作简便,宜于向疆内其它地区进行推广应用。 相似文献
77.
宫颈癌194例回顾性分析 总被引:1,自引:0,他引:1
目的探讨宫颈癌的发病年龄与临床特点及病理类型的关系。方法宫颈癌患者194例,分为年轻组(≤35岁)和中老年组(〉35岁)组,进行临床特点分期,病理类型及细胞分化等临床资料对比分析。结果两组患者在临床特点、病理类型差异有统计学意义。≤35岁组临床表现以接触性阴道流血为主;≤Ⅱa期占94.7%,≥Ⅱb期占5.3%;鳞癌占89.5%,腺癌占10.59%,其他类型占0。〉35岁组临床表现以不规则阴道流血和绝经后出血为主;≤Ⅱa期占87.7%,≥Ⅱb期占12.3%;鳞癌占90.4%,腺癌占7.5%,其他类型占2.1%。结论〉35岁组临床期别较高,预后不良。≤35岁组临床期别较低,但腺癌较多。 相似文献
78.
宫颈鳞癌中Cyclin E的表达和HPV16感染的相关研究 总被引:4,自引:0,他引:4
目的探讨Cyclin E在宫颈鳞状细胞癌中的表达及其与HPV16感染的关系.方法应用免疫组化S-P法对34例宫颈鳞状细胞癌组织进行Cyclin E与HPV16的检测,并与宫颈不典型增生和正常宫颈组织进行比较.结果正常宫颈组织无Cyclin E表达,宫颈不典型增生组织仅有少量袁达(11.11%),宫颈鳞状细胞癌有58.52%表达(P<0.001),且与HPV16感染有明显相关性(P<0.05).结论高危HPV感染是宫颈癌的重要病因,HPV感染通过多种途径改变了细胞的周期性调控,诱发细胞周期GI-S期检测点异常,引起细胞恶性增生,HPV感染与Cyclin E异常表达在宫颈癌的发生发展中起重要作用. 相似文献
79.
Jing Guo Ying Zhang Xiaofei Chen Lin Sun Kai Chen Xiugui Sheng 《Journal of minimally invasive gynecology》2019,26(3):484-491
Study Objective: To compare the surgical and oncologic outcomes between abdominal radical trachelectomy (ART) and radical hysterectomy (RH) for stage IA2-IB1 cervical cancer.Design: A retrospective cohort study (Canadian Task Force classification II-2).Setting: Shandong Cancer Hospital, Shandong, China.Patients: Three hundred twenty-nine patients with IA2-IB1 cervical cancer.Interventions: All patients underwent ART or RH.Measurements and Main Results: All patients were divided into ART (n?=?143) and RH (n?=?186) groups according to the surgical approach. Additionally, oncologic and fertility outcomes were compared for different tumor pathologies and sizes in ART patients. The ART group had similar case characteristics as the RH group, except that the ART group had a longer surgical time. During a similar follow-up period, there were 4 (2.9%) recurrences and 3 (2.2%) patients who died from recurrence in the ART group compared with 8 (4.6%) recurrences and 4 (2.3%) patients who died from recurrence in the RH group (p?=?.444 and p?=?.999, respectively). In the ART group, squamous cell carcinoma (SCC) patients had a 5-year overall survival and pregnancy rate similar to those of non-SCC patients (98.1% vs 96.8%, p?=?.999; 33.3% vs 26.7%, p?=?.873), and patients with tumors ≤2 cm and 2 to 4 cm experienced a similar 5-year overall survival rate (97.0% vs 98.6%, p?=?.999), except patients with tumors ≤2 cm had a higher pregnancy rate (45.2% vs 17.2%, p?=?.020).Conclusion: ART seems to have similar surgical and oncologic outcomes to RH, except ART has a longer surgical time. Both non-SCC patients and stage IA2-IB1 patients with 2- to 4-cm tumors can undergo ART safely. Patients with tumors ≤2 cm have a higher pregnancy rate than patients with 2- to 4-cm tumors. 相似文献
80.
人宫颈癌脱落细胞端粒酶活性检测的意义 总被引:1,自引:0,他引:1
目的 研究宫颈上皮内瘤样病变(CIN )和宫颈癌脱落细胞端粒酶激活的意义。方法 采用端粒酶PCR-ELISA法检测13例CIN和17例宫颈癌脱落细胞端粒酶活性,并与相应的组织标本中端粒酶活性相比较,11例正常宫颈脱落细胞作为对照。结果8例(61.54%)CIN、14例(82.35%)宫颈癌脱落细胞表达端粒酶活性,正常宫颈无端粒酶活性,CIN、宫颈癌及正常宫颈脱落细胞端粒酶活性平均值分别为0.328±0.192、1.329±0.259和0.039±0.084,三组间端粒酶表达率和量存在显著差异。CINⅠ、Ⅱ、Ⅲ级之间端粒酶活性无明显差异。CIN及宫颈癌组织中端粒酶活性和相应脱落细胞一致。结论 端粒酶的激活是宫颈癌的早期改变,在宫颈癌发生发展过程中起重要作用;宫颈脱落细胞和组织中端粒酶活性可能成为宫颈癌早期诊断、预后判断和肿瘤浸润的标记物。 相似文献