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71.
72.
Summary To explore the possibility to employ99mTc-MIBI to monitor biological response of tumor cells after irradiation and to observe the relation between the radiation
doses and the uptake levels of99mTc-MIBI in tumor cells, the cells were irradiated with a single dose of 2 Gy, 10 Gy and 20 Gy respectively. The uptake of99mTc-MIBI in each dosage group was determined before and 24, 48, 72 h after irradiation respectively. Apoptosis index (AI),
plating efficiency (PE) of tumor cells was simultaneously determined. There was a positive correlation between uptake levels
of99mc-MIBI and AI(r = −0.91,P< 0.05). A negative correlation was noted between the uptake levels and PE (r = −0.86,P< 0.05). It is suggested that99mTc-MIBI may be used as a tracer to monitor the change of viability state of tumor cells after being irradiated with different
doses. 相似文献
73.
观察肝硬变患者幽门螺杆菌感染的差异性及其对病情的影响.结果发现随着肝功能的减退,ChildA组,ChildB组,ChildC组HP的感染率逐步升高,CagA、VacA阳性率也逐步升高,ChildC与各组比较HP的感染率,CagA、VacA的阳性率均显著增高,差异有显著性(P<0.05),胃排空无差异(P>0.05).其余各组间比较无差异(P>0.05).提示肝硬变患者与对照组比较HP的感染率及其菌株无显著差异,胃的排空与HP的感染无关,肝脏功能状况与HP感染相关性有待进一步研究. 相似文献
74.
为研究金丝桃的抗脂质过氧化作用,用分光光度法测定了金丝桃提取物对大鼠离体组织匀浆的脂质过氧化及由Fe2+-H2O2体系、Fe2+-VitC体系和Fe2+-Cys体系诱导的脂质过氧化的抑制作用。发现金丝桃提取物对大鼠肝、心、肾组织匀浆脂质过氧化和线粒体诱导的脂质过氧化具有抑制作用并表现出剂量依赖关系,而且提取物F003的抑制作用要强于F004、F005的抑制作用。认为金丝桃具有较好的抗脂质过氧化作用,具有进一步研究与开发价值。 相似文献
75.
建立了生物组织中胺甲硫磷和甲基毒死蜱的反相高效液相色谱分析方法。选用YWG-C18H375mm(内径)×200mm柱作为分析柱,流动相选用80∶20(V/V)的甲醇/水二元体系,流速为1.0ml/min,检测波长胺甲硫磷为252nm,甲基毒死蜱为290nm。该方法简单、快速、准确。其最小检出量为2.5×10-8g,最小检出浓度为0.25mg/L。 相似文献
76.
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
77.
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
78.
79.
《Injury》2021,52(8):2322-2326
AimsFractures of the pelvis and acetabulum are often the consequence of high energy trauma in young individuals or fragility fractures in osteoporotic bone. They can be life-threatening or life changing injuries. No published data exists comparing body mass index (BMI) and mortality for this patient group. The aim of this study was to identify if low BMI (<18.5) was a predictor of morbidity and mortality for patients with these injuries.Patients and MethodsOf the 1033 patients with pelvic or acetabular fractures referred to a single level 1 major trauma centre (MTC) over a 4.5-year period (August 2015 - January 2020); we retrospectively analysed data for all admitted patients. Data was collected on demographics, injury pattern, operative intervention and complications. Comparison was made between patients that were underweight (BMI<18.5) and patients that were not. Both in-hospital and post discharge complications were recorded including pulmonary embolus (PE), deep venous thrombosis (DVT), ileus, infection, loss of reduction and mortality at 6 months.Results569 patients admitted to the MTC with a pelvic or acetabular fracture were included in our analysis. Underweight patients had a statistically significant increase in mortality both in-hospital (p = 0.019) and at 6 months post injury (p = 0.039) when compared to other BMI groups. No statistical significance was found between these BMI groups comparing morbidity: DVT (p = 0.712), PE (p = 0.736) nor ileus (p = 0.149). Covariate analysis showed that a low BMI was associated with triple the in-hospital mortality after correction for age and energy of injury (adjusted OR 3.028, 95% CI 1.059-8.659).ConclusionThis is the first published study that demonstrates a statistically significant increase in mortality in patients with pelvic or acetabular fractures who are underweight. Surgeons should carefully consider appropriate peri-operative optimisation for these patients. Further investigation into the effects of low BMI and response to trauma is required. 相似文献
80.
《Injury》2021,52(8):2339-2343
The technique for placing iliosacral screws typically involves the surgeon using an inlet and outlet view as the primary means for assessing the anteroposterior and craniocaudal position of the guidewire, respectively. However, because these views are rarely, if ever, orthogonal to one another, this technique will inevitably lead to unintentional biplanar movements. These unintentional movements, in turn, require correction, which can increase operating room and fluoroscopic time. Here we calculate the degree and magnitude of these unintentional movements. Additionally, we provide a simple technique for minimizing or eliminating them altogether. 相似文献