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81.
Histocompatibility is crucial in effecting survivalof allografts.Due to differences in histocompatibilitybetween donor and recipient,rejection would happento some extent after transplantation. Therefore,theevaluation of differences in histocompatibility betweendonor and recipient would be contributive to selectionof donor and judgement on prognosis oftransplantation. HLA typing and mixed lymphocyticreaction (MLR) are the classical methods to evaluatethe histocompatibility between donor and r… 相似文献
82.
为探讨临床上比较罕见的砂粒性骨化纤维瘤(psammomatoid
ossifying fibroma,POF)的临床特征、诊断与治疗方法,分析了6例POF的临床资料并综合文献,提出POF是一种以青少年为主、具有局部侵袭性的良性肿瘤,有明确的组织形态特征,临床症状特别是CT扫描是临床诊断的基础,治疗原则是在彻底清除病灶的基础上,兼顾面容与功能的保护。 相似文献
83.
为了研究血管紧张素Ⅱ(AngⅡ)诱导凋亡的机制,将人脐静脉内皮细胞培养至第3代,用不同浓度Ang Ⅱ培养不同时间,用TUNEL检测细胞凋亡.Bax和Bcl-2蛋白表达用Western Blot和图像分析法测定.结果发现Ang Ⅱ组的凋亡阳性率极显著高于对照组;Bax的表达极显著地升高且具有时间和剂量依赖性,Bcl-2无显著变化,Bax/Bcl-2比值极显著地增加.提示AngⅡ通过诱导Bax的高表达,致Bax/Bcl-2比值极显著地增加而诱发凋亡. 相似文献
84.
目的 研究激光照射的生物效应。方法 采用低能量He Ne激光照射小鼠 ,每天 1次 ,每次 10min ,照射 7天后 ,处死小鼠。测定小鼠骨髓嗜多染红细胞微核的出现率。结果 经低能量He Ne激光照射的小鼠的细胞微核率与对照组比较无差异 (P >0 .0 5 )。结论 受低能量He Ne激光照射后小鼠骨髓嗜多染红细胞微核率无显著增加 ,治疗用低能量的He Ne激光不会致突变 相似文献
85.
Yi-ting Cai Cheng-liang Xiong Tian-shu Liu Shi-liang Shen Jin-peng Rao Feng Qiu 《Andrologia》2021,53(8):e14144
This study aimed at the efficacy of sequential treatment of bone marrow-derived mesenchymal stem cell secretion for busulfan-treated azoospermia in mice. The conditioned media (CM) was obtained from bone marrow mesenchymal stem cells (MSCs) or 293 cells. Chemically induced azoospermia mice received 200 μl MSC-CM or 293-CM twice a week intravenously for three consecutive weeks. The histological assessment of spermatogenic recovery quantifying the expression of meiosis-associated genes, and Sertoli cell barrier functional factors were assessed. The characteristics of TM4 cells (Sertoli cell line) after pre-incubation of MSC-CM in vitro were also obtained. The MSC-CM group had the most spermatogenic colonies among the three groups (p < .05), but no spermatids were seen. Expressions of the meiosis-associated genes Dazl, Vasa, Miwi, Stra8, CyclinA1, Pgk2 and Scp3 in MSC-CM testis were remarkably higher compared with 293-CM and busulfan groups respectively (p < .05). The levels of Sertoli cell barrier functional factors, for example ICAM-1 and N-cadherin, were significantly increased during MSC-CM treatment (p < .05). Moreover, pre-incubation of MSC-CM particularly accelerated the CD54 (ICAM-1) and CD44 expressions of TM4 cells and promoted cell inherent adhesion. MSC-CM treatment can significantly improve the short-term restoration of spermatogonial structures of chemically induced azoospermia related to facilitating Sertoli cell adhesion integrity. 相似文献
86.
Xu Yangyang He Qi Wang Mengqi Gao Yuan Liu Xiaowei Li Denghui Xiong Botao Wang Wei 《Neurosurgical review》2021,44(1):115-127
Neurosurgical Review - Magnetic resonance imaging-guided focused ultrasound (MRgFUS) neurosurgery is a new option for medication-resistant Parkinson’s disease (PD), but its safety and... 相似文献
87.
Venkatsaiakhil Tirumala Christian Klemt Liang Xiong Wenhao Chen Janna van den Kieboom Young-Min Kwon 《The Journal of arthroplasty》2021,36(1):291-297
BackgroundDiagnosing a periprosthetic joint infection (PJI) can be challenging and often requires a combination of clinical and laboratory findings. Monocyte/lymphocyte ratio, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio (PLR), and platelet/mean platelet volume ratio (PVR) are simple predictors for inflammation that can be readily obtained from complete blood count. The aim of this study is to evaluate the diagnostic utility of these markers in predicting PJI in total knee arthroplasty (TKA) patients.MethodsA total of 538 patients who underwent revision TKA with calculable marker ratios prerevision in 2 groups were evaluated: (1) 206 patients with a preoperative diagnosis of PJI (group I) and (2) 332 patients treated for revision TKA for aseptic failures (group II). The diagnostic abilities of the markers were assessed via receiver operator characteristic curve analysis.ResultsThe optimal threshold of PVR at 30.82 had the highest sensitivity of 87.7%, while the optimal threshold of PLR at 234.13 had the highest specificity of 82.5%. Both PLR and PVR, when combined with Musculoskeletal Infection Society thresholds for erythrocyte sedimentation rate, C-reactive protein, synovial WBC, and PMN%, achieve significantly higher sensitivity and specificity rates for PJI at or above 97% (PLR: 99.03%; 98.80%; PVR: 98.54%;97.89%).ConclusionOur study demonstrates that PVR and PLR, which are readily available and inexpensive to obtain from complete blood counts, when combined with serum and synovial fluid markers have increased sensitivity and specificity comparable to that of alpha defensin. This suggests that PVR and PLR can be used together with other hematologic and aspirate markers to increase the accuracy of PJI diagnosis in TKA patients. 相似文献
88.
Christian Klemt Paul Walker Anand Padmanabha Venkatsaiakhil Tirumala Liang Xiong Young-Min Kwon 《The Journal of arthroplasty》2021,36(4):1393-1400
BackgroundRacial and ethnic disparities in access to hip and knee total joint arthroplasty (TJA) and postoperative outcomes have wide-reaching implications for patients and the health care system. The aim of this study is to evaluate the effect of ethnicity on clinical outcomes and complications following revision hip and knee TJA.MethodsA single-institution, retrospective analysis of a consecutive series of 4424 revision hip and knee TJA patients was evaluated. Student’s t-test and chi-squared analysis were used to identify significant differences in patient demographics and clinical outcomes between Caucasians and various ethnic minorities, including African Americans, Hispanics, and Asians.ResultsWhen compared with white patients, African American patients demonstrated a significantly higher BMI (P = .04), ASA score (P = .04), length of hospital stay (P = .06), and postoperative infection rates (P = .04). Hispanics demonstrated a significantly higher BMI (P = .04), when compared with white patients, alongside a significantly higher risk for postoperative infection (P < .01). African American demonstrated a significantly higher ASA score (P = .02; P = .03), when compared with Hispanics and Asians, alongside a significantly increased length of stay (P = .01) and higher risk for postoperative infection (P = .02).ConclusionThe study findings demonstrate an underutilization of revision TJA by ethnic minority groups, suggesting that disparities in access to orthopedic surgery increase from primary to revision surgery despite higher failure rates of minority ethnic groups reported after primary TJA surgery. In addition, inferior postoperative outcomes were associated with African Americans and Hispanics, when compared to white patients, with African Americans demonstrating the highest risk of postoperative complications. 相似文献
89.
Feng Zhang Yingmei Wang Yuying Wang Xinli Wang Dawei Zhang Xiong Zhao Runmin Jiang Yu Gu Guifang Yang Xin Fu Longyong Xu Longxia Xu Liting Zheng Jing Zhang Zengshan Li Qingguo Yan Jianguo Shi Albert Roessner Zhe Wang Qing Li Jing Ye Charlie Degui Chen Shuangping Guo Jie Min 《Journal of bone and mineral research》2021,36(10):1931-1941
90.
目的探究动态增强磁共振成像(DCE-MRI)用于评估女性乳房乳头乳晕血供特点的可行性,为乳房整形手术提供乳头乳晕的血供参考。方法从2012年3月至2019年10月华中科技大学同济医学院附属同济医院影像数据库中收集女性乳腺DCE-MRI图像资料,选择未发现肿物的正常乳房的DCE-MRI图像进行研究。在西门子工作站将患者乳腺DCE-MRI图像通过图像减影获取乳房血管图像,分别对轴位、冠状位和矢状位的最大密度投影(MIP)图像进行评估,结合三维MIP图像识别所有供应乳头乳晕的血管。乳头乳晕的血供被划分为内上、内侧、内下、外上、外侧、外下、中央、上方和下方9个象限,对各个象限血管进行统计和分析,并测量血管至乳房皮肤表面投影的最大距离。采用SPSS 19.0软件进行统计分析,通过卡方检验分别比较左侧与右侧乳房的乳头乳晕复合体(NAC)血供象限分布构成比。计算血管到皮肤距离的平均值、标准差及95%置信区间,通过方差分析比较各象限血管至皮肤距离的差异。P<0.05为差异具有统计学意义。结果共收集到245例患者490只女性乳房DCE-MRI图像,其中97例患者97只乳房发现有乳腺肿物,其余393只为正常乳房(97例单侧乳房、148例双侧乳房),将其作为研究对象。患者年龄23~72岁,平均43.7岁。393只乳房(左侧200只、右侧193只)共发现有637条(左侧311条、右侧326条)乳头乳晕供应血管。在637条血管中,内上象限269条(42.2%),外上180条 (28.3%),内侧57条(8.9%),下方37条(5.8%),中央30条(4.7%),内下25条(3.9%),外下25条(3.9%),上方11条(1.7%),外侧3条(0.5%)。卡方检验表明左侧乳房和右侧乳房在NAC血供象限分布构成比差异无统计学意义(χ2 =6.4,P=0.602)。除中央象限血管以外,所有血管到皮肤表面投影最大距离的平均值为0.91 cm, 95%置信区间为0.86~0.96 cm。方差分析表明各象限供血血管到皮肤投影的最大距离,差异有统计学意义(F=11.4,P<0.001)。结论 DCE-MRI可以清晰地显示乳头乳晕的血供来源。乳头乳晕血供主要来源于内上象限和外上象限的血管,血管在皮下约1 cm深度走行。 相似文献