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31.
目的:大黄素对白细胞介素1β诱导NRK52E细胞转分化有显著抑制作用。实验拟进一步观察转化生长因子β1在白细胞介素1β诱导大鼠肾小管上皮细胞-肌成纤维细胞转分化及大黄素抑制作用中的意义。方法:实验于2006-10/2007-05在泸州医学院附属医院免疫实验室完成。⑴实验材料及分组:以培养的大鼠肾小管上皮细胞株(NRK52E)为观察对象,按如下分组分别添加不同处理因素:①对照组:仅加入体积分数为0.05小牛血清的高糖DMEM培养基。②白细胞介素1β诱导组:加含白细胞介素1β终浓度为10μg/L的高糖DMEM培养基。③SB431542阻断组:加含白细胞介素1β终浓度为10μg/L及SB431542终浓度为10μmol/L的高糖DMEM培养基。④白细胞介素1β 大黄素组:同时加分别含白细胞介素1β终浓度为10μg/L及大黄素终浓度为25mg/L的高糖DMEM培养基。⑵实验评估:培养48h后用倒置相差显微镜观察细胞形态,细胞免疫化学染色法检测肌酸激酶、α-平滑肌肌动蛋白及转化生长因子β1的表达。结果:①白细胞介素1β可诱导部分细胞由卵圆形转变为梭形,且肌酸激酶表达减弱(P<0.01),α-平滑肌肌动蛋白及转化生长因子β1表达显著增强(P<0.01)。②SB431542特异性抑制转化生长因子β1作用后,白细胞介素1β诱导的细胞形态改变受抑,同时肌酸激酶表达增强(P<0.01),α-平滑肌肌动蛋白表达减弱(P<0.01),但转化生长因子β1的表达却无明显变化。③大黄素对白细胞介素1β诱导的细胞形态改变及肌酸激酶、α-平滑肌肌动蛋白的表达有明显抑制作用,其抑制作用与SB431542的作用相比无显著差异;同时,大黄素对白细胞介素1β诱导的转化生长因子β1的表达也有明显抑制作用(P<0.01)。结论:转化生长因子β1可能介导了白细胞介素1β诱导大鼠肾小管上皮细胞-肌成纤维细胞转分化,并参与了大黄素抑制白细胞介素1β诱导大鼠肾小管上皮细胞转分化的作用。  相似文献   
32.
Amniotic fluid cells (AFCs) have been proposed as a valuable source for tissue engineering and regenerative medicine. However, before clinical implementation, rigorous evaluation of this cell source in clinically relevant animal models accepted by regulatory authorities is indispensable. Today, the ovine model represents one of the most accepted preclinical animal models, in particular for cardiovascular applications. Here, we investigate the isolation and use of autologous ovine AFCs as cell source for cardiovascular tissue engineering applications. Fetal fluids were aspirated in vivo from pregnant ewes (n = 9) and from explanted uteri post mortem at different gestational ages (n = 91). Amniotic non‐allantoic fluid nature was evaluated biochemically and in vivo samples were compared with post mortem reference samples. Isolated cells revealed an immunohistochemical phenotype similar to ovine bone marrow‐derived mesenchymal stem cells (MSCs) and showed expression of stem cell factors described for embryonic stem cells, such as NANOG and STAT‐3. Isolated ovine amniotic fluid‐derived MSCs were screened for numeric chromosomal aberrations and successfully differentiated into several mesodermal phenotypes. Myofibroblastic ovine AFC lineages were then successfully used for the in vitro fabrication of small‐ and large‐diameter tissue‐engineered vascular grafts (n = 10) and cardiovascular patches (n = 34), laying the foundation for the use of this relevant pre‐clinical in vivo assessment model for future amniotic fluid cell‐based therapeutic applications. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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34.

INTRODUCTION

The effect of primary total knee replacement on the employment status of 56 patients under 60 years of age was examined at a mean follow-up of 64 months.

PATIENTS AND METHODS

A total of 56 primary total knee replacements performed on patients under the age of 60 years by two surgeons between 1996 and 2003 were retrospectively assessed by postal questionnaire. Patients were selected from databases held at Holly House and Newham Hospital NHS Trust.

RESULTS

Overall, 97.5% of patients who were employed before their operation, returned to their previous work. However, in patients not working prior to total knee replacement none were employed after their operation.

CONCLUSIONS

Total knee replacement may be a valuable tool to help some patients to continue working but may not affect patients who are already unemployed.  相似文献   
35.
In a patient with mechanical aortic valve prosthesis, a high transvalvular gradient was detected 16 years following the procedure, without echocardiographic clues for the underlying etiology. Intraoperatively, a stenosing pannus ring was found and excised. This pathological entity should be considered in cases of unclear transprosthetic gradient and early operation should be encouraged in symptomatic patients.  相似文献   
36.
Background Various laser and light therapy have been increasingly used for the treatment of acne vulgaris. Patients and methods Twenty patients with facial acne were treated using intense pulsed light (IPL) on one side of the face and pulsed dye laser (PDL) on the other to compare the efficacy and safety of IPL and PDL. Treatment was performed 4 times at 2‐week intervals. Treatment effectiveness was determined using lesion counts, acne severity, patient subjective self‐assessments of improvement, and histopathological examinations, which included immunohistochemical staining for transforming growth factor‐β (TGF‐β). Results Numbers of total acne lesions decreased following both treatments. For inflammatory lesions such as papules, pustules and nodules, IPL‐treated sides showed an earlier and more profound improvement than PDL‐treated sides. However, at 8 weeks after the 4th treatment, a rebound aggravation of acne was observed on IPL‐treated sides. On the contrary, PDL produced gradual improvements during the treatment sessions and these improvements lasted 8 weeks after the 4th treatment. Non‐inflammatory lesions as open and closed comedones also showed improvement following both treatments and PDL‐treated sides showed better improvement as the study proceeded. Histopathological examinations showed amelioration in inflammatory reactions and an increase in TGF‐β expression after both treatments, which were more prominent for PDL‐treated sides. Conclusion Both PDL and IPL were found to treat acne effectively, but PDL showed a more sustained effect. TGF‐β might play a key role in the resolution of inflammatory acne lesions.  相似文献   
37.
Sexual assaults on girls occur at an alarming rate representing a significant public health problem, but difficulties in correctly identifying the problem, managing the child and reporting for legal purposes have been recognized. We describe data obtained on 154 recent cases of child and adolescent sexual assault. Results indicate that those at highest risk of sexual assault are girls at age of 11–15 years having a stepfather, although the most girls at age of >15 were assaulted by strange men with higher incidence of cross-race assault. Over a quarter of girls showed signs of physical trauma with face and neck as most common site of contact. A total of 17.5% reported threat of violence or with weapons and 9.7% had alcoholic influence. Pattern and incidence of genital injuries were described. Received: 3 June 1997 / Accepted: 22 August 1997  相似文献   
38.
39.

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.  相似文献   
40.
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