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91.
BACKGROUND: Biomechanical properties in terms of residual strains in diabetic small intestine have not been studied. Furthermore, no data have been reported on affect of gliclazide on gastrointestinal complications of diabetes. AIMS: To determine remodelling of zero-stress state of small intestine in streptozotocin-induced diabetic rats and effect of gliclazide treatment. MATERIALS: Morphological properties and residual strains were studied in duodenum, jejunum and ileum obtained from diabetic rats, gliclazide-treated diabetic rats and normal rats (n = 8 each group). METHODS: Diabetes was induced by single intraperitoneal injection of 65 mg/kg streptozotocin. Gliclazide (10 mg kg(-1) day(-1) was injected directly into stomach lumen by intragastric gavage twice daily. Experimental period was 35 days. To approach no-load state; intestinal segments were surgically excised and cut transversely into short ring-shaped segments. Each ring was cut radially to obtain geometry of zero-stress state. Circumferential length, the wall thickness and opening angle were measured from digital images of each specimen and residual strains were computed. RESULTS: Blood glucose level of diabetic group (approximately 20 mmol/l) was consistently higher than that in normal group (approximately 4 mmol/l) after induction of diabetes (p < 0.001). Gliclazide lowered average blood glucose level to between 10 and 15 mmol/l (p < 0.001). Plasma insulin levels of both diabetic groups (average between 10 and 15 pmol/l) were significantly lower than those in normal group (average approximately 18 pmol/l, p < 0.05). Wet weight per unit length and wall thickness of duodenum, jejunum and ileum were significantly higher in Diabetes group than those in Normal group (p < 0.05). Opening angle and absolute value of residual strain were significantly smaller in duodenum and larger in jejunum and ileum in Diabetes group than in Normal group (p < 0.001). Gliclazide treatment partly restored these changes (p < 0.05). CONCLUSIONS: Diabetes induced morphometric and biomechanical remodelling in intestine. Gliclazide partly restored these changes.  相似文献   
92.
目的 分析深圳市2015—2020年放射工作人员上岗前职业健康检查染色体畸变率与微核率的水平及其分布特征,为加强放射工作人员辐射防护和职业健康管理提供科学依据。 方法 选取2015—2020年在深圳市职业病防治院接受上岗前职业健康检查的2 777名放射工作人员开展横断面研究,其中男性2 210名、女性567名,年龄17~69(27.6±6.8)岁,将受检者按年龄分为5组:17~20岁、21~30岁、31~40岁、41~50岁、51~69岁。采用全血微量培养法制备受检者的淋巴细胞微核和染色体,应用全自动染色体扫描分析系统对每名受检者的100个淋巴细胞染色体中期分裂相进行分析,统计双着丝粒体、着丝粒环和无着丝粒体等染色体畸变类型,比较不同年龄组以及同年龄组不同性别受检者染色体畸变情况和微核情况的差异。计量资料的组间比较采用方差分析;染色体畸变和微核的分布服从泊松分布,采用非参数检验,2组间比较采用Mann-Whitney U检验,多组间比较采用Kruskal-Wallis秩和检验。受检者年龄与染色体畸变率、微核率的相关性分析采用Spearman秩相关分析。 结果 2 777名受检者的染色体畸变(双着丝粒体+着丝粒环+无着丝粒体)率为(0.072±0.005)%、双着丝粒体+着丝粒环畸变率为(0.016±0.002)%、染色体畸变细胞率为(0.068±0.005)%、微核率为(0.43±0.01)‰、微核细胞率为(0.40±0.01)‰、淋巴细胞转化率为(85.07±3.16)%。各年龄组间染色体畸变率、双着丝粒体+着丝粒环畸变率、染色体畸变细胞率以及各年龄组不同性别受检者的染色体畸变率、染色体畸变细胞率间的差异均无统计学意义(χ2=1.193、0.931、0.691,Z=?0.929~?0.059,均P>0.05)。与17~20岁年龄组相比,其余各年龄组受检者的微核率、微核细胞率均较高,淋巴细胞转化率均较低,且差异均有统计学意义(Z=?6.981~?2.510,F=4.922~52.860,均P<0.05);受检者的微核率和微核细胞率均与年龄呈正相关(r=0.166、0.168,均P<0.001),而淋巴细胞转化率与年龄呈负相关(r=?0.197,P<0.001);21~30岁年龄组、31~40岁年龄组女性受检者的微核率、微核细胞率以及17~20岁年龄组、21~30岁年龄组女性受检者的淋巴细胞转化率均显著高于同年龄组的男性受检者,且差异均有统计学意义(Z=?4.826~?3.516,F=6.947、14.563,均P<0.01)。 结论 深圳市2015—2020年放射工作人员上岗前职业健康检查染色体畸变率与微核率均未超过国内文献报道的健康人群的本底水平范围,但有随年龄增大而升高的趋势,需加强放射工作人员的辐射防护与职业健康管理。  相似文献   
93.
94.
The formation of natural foci of trichinelliasis was shown to depend on the established biocenotic relations between carnivorous animals. A highly intensive transmission of the invasion was recorded in continental areas where predators suffer from the lack of food in winter. Identification of the isolated Trichinella samples using single-pair cross hybridization and isoenzyme identification methods showed that the parasites of predators are T. spiralis nativa on the Northern Caspian coast and T. s. nelsoni on the Southern coast.  相似文献   
95.
96.
目的对比分析小儿伤科汤剂与小儿伤科泡腾颗粒对闭合性骨折模型大鼠的治疗效果。方法选取45只幼年雄性SD大鼠作为研究对象,利用骨折器建立大鼠胫骨闭合性骨折模型。根据随机数字表原则,将模型大鼠随机分为对照组、汤剂组和颗粒组,每组15只。所有大鼠手法复位固定后,对照组大鼠采用温开水灌胃作为对照,汤剂组大鼠采用小儿伤科汤剂灌胃治疗,颗粒组大鼠采用小儿伤科泡腾颗粒灌胃治疗。分别在治疗14 d、28 d、35 d时,每组处死5只大鼠,采集腹主动脉血检测血清钙、血清磷、血清碱性磷酸酶(ALP)指标,同时对患肢进行X摄片检查骨折愈合情况,以Lane-Sandhu X射线评分标准评价骨缺损修复情况。结果治疗14 d时,三组大鼠血清钙、血清磷、血清ALP指标比较差异均无统计学意义(P>0.05)。治疗35 d时,汤剂组和颗粒组大鼠血清钙指标低于对照组,差异有统计学意义(P<0.05)。但汤剂组和颗粒组大鼠比较差异无统计学意义(P>0.05)。治疗28 d、35 d时,汤剂组和颗粒组大鼠血清ALP高于对照组,差异有统计学意义(P<0.05)。但汤剂组和颗粒组大鼠比较差异无统计学意义(P>0.05)。治疗14 d时,三组大鼠Lane-Sandhu评分比较差异无统计学意义(P>0.05)。治疗28 d、35 d时,汤剂组和颗粒组大鼠Lane-Sandhu评分均高于对照组,差异有统计学意义(P<0.05)。但汤剂组和颗粒组大鼠Lane-Sandhu评分比较差异无统计学意义(P>0.05)。结论小儿伤科汤剂与小儿伤科泡腾颗粒治疗闭合性骨折模型大鼠效果相当。  相似文献   
97.
ObjectiveTo study changes in T lymphocyte subsets, cytokines, and liver enzymes in patients with malignant obstructive jaundice (MOJ) before and after external biliary drainage (percutaneous transhepatic cholangiography drainage, PTCD) and internal biliary drainage (percutaneous transhepatic insertion of biliary stents, PTIBS).MethodsMOJ patients undergoing PTCD (n = 44) and PTIBS (n = 38) at our hospital were enrolled in the study from January 2017 until December 2019. Peripheral blood total bilirubin (TBIL), direct bilirubin (DBIL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), CD3+%, CD4+%, CD4+/CD8+ ratio, interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α were measured before and 1 week after biliary drainage.ResultsThere was no significant difference in any parameter between the two groups before biliary drainage. TBIL, DBIL, AST and ALT following PTCD were significantly lower than before PTCD. By contrast, CD3+%, CD4+%, CD4+/CD8+ ratio, IL-2, IL-6 and TNF-α showed no significant difference before and 1 week after PTCD. TBIL, DBIL, AST, ALT, IL-6 and TNF-α were significantly lower following PTIBS than before PTIBS. CD3+%, CD4+%, CD4+/CD8+ ratio and IL-2 were significantly higher following PTIBS than before PTIBS.ConclusionBoth PTCD and PTIBS were effective for treatment of MOJ, but PTIBS was more beneficial for recovery of immune function.  相似文献   
98.
ObjectiveTo investigate mental health status and associated factors among caregivers of older adults during the COVID-19 epidemic in China.MethodsFrom March 1 to 31, 2020, 916 caregivers of older adults participated in an online cross-sectional survey on the prevalence of anxiety, depression, and sleep problems. The seven-item Generalized Anxiety Disorder Scale (GAD-7) was administered to measure anxiety symptoms, the two-item Patient Health Questionnaire (PHQ-2) was used to assess depressive symptoms, and a self-developed questionnaire was used to assess sleep quality and duration. Six questions about COVID-19-related experiences were used to assess community-level infection contact and the level of exposure to media information. The prevalence rates of anxiety, depression and sleep problems were computed. The Wald χ2 were applied to compare the differences between subgroups. Multiple logistic regression analyses were performed to investigate factors associated with anxiety, depression, sleep problems, and multimorbidity.ResultsThe prevalence rates of anxiety, depression, and sleep problems were 46.8%, 29.8%, and 10.8%, respectively. Approximately 263 participants (28.7%) presented with two or more mental health problems. Being female (OR, 2.254; 95% CI, 1.510–3.363), having community-level COVID-19 contact (OR, 1.856; 95% CI, 1.189–2.898), and having a mental disorder (OR, 3.610; 95% CI, 1.644–7.930) were associated with increased risk of multimorbidity among caregivers. Caregivers who preferred positive information (OR, 0.652; 95% CI, 0.472–0.899) had reduced risk of multimorbidity.ConclusionAnxiety and depression were common among caregivers of older adults during the COVID-19 epidemic. Being female and having community-level COVID-19 contact were independent risk factors for experiencing multiple mental health problems. Preexisting mental disorders increased the risk of multimorbidity among caregivers, while enhanced access to positive media information decreased the risk of multimorbidity.  相似文献   
99.
Cancer is a major cause of morbidity and mortality. Chemotherapy is one of the main means of cancer treatment. Conventional chemotherapy agents kill rapidly proliferating cells, resulting in some of the most common side effects of chemotherapy. Liposome-encapsulated drugs offer the possibility to increase target efficacy as well as reducing toxic side effects of chemotherapeutic drugs. However, the target specificity of liposome is dissatisfied. We urgently need to develop new approaches to improving drug target efficacy. Recently, sonodynamic therapy (SDT) of cancer, which is based on preferential uptake and retention of a sonosensitizer in tumor tissues and subsequent activation of drug by ultrasound radiation, is a developing field. In this article, we propose the use of sonosensitizers in combination with liposome to target chemotherapy drugs directly to tumor cells. SDT with low-intensity ultrasound combined with a sonosensitizer may be a promising approach to cancer therapy.  相似文献   
100.
 目的:观察肿瘤坏死因子α(TNF-α)对肝X受体α(LXRα)启动子活性及其下游ATP结合盒转运蛋白(ABCA1和ABCG1)表达的影响,从而探讨TNF-α加速HepG2细胞内胆固醇积聚的分子机制。方法:构建LXRα基因的启动子表达载体,观察炎症因子TNF-α对LXRα启动子活性的影响,进一步将HepG2细胞分为对照组(control)、TNF-α组(20 μg/L)、高脂组(LDL,100 mg/L)及联合处理组(TNF-α 20 μg/L+ LDL 100 mg/L)。采用实时定量PCR和Western blotting检测LXRfα、ABCA1和 ABCG1的mRNA及蛋白的表达。[3H ]标记胆固醇,液体闪烁计数法检测胆固醇外流量。油红O染色和定量比色法分析细胞内胆固醇的含量。结果:成功构建LXRα启动子的萤火虫萤光素酶报告质粒,证明了该启动子有明显活性,TNF-α能明显抑制LXRα启动子的活性。进一步检测发现,和对照组相比,TNF-α下调了LXRα、ABCA1和ABCG1 mRNA与蛋白表达。高脂组胆固醇外流量增加,而TNF-α组胆固醇外流量明显降低。油红O染色显示,TNF-α使细胞内脂质染色明显增加。结论: TNF-α可通过抑制LXRα启动子活性从而抑制HepG2细胞内胆固醇外流导致肝细胞内脂质异常积聚。  相似文献   
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