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41.
目的:采用不同方法对白血病HL60细胞株进行冻存和复苏,观察生物学特性改变,筛选最佳冻存复苏方案。方法:实验于2006-04/06在吉林医药学院临床检验实验室(国家三级标准)进行。①HL60细胞株由中国科学院上海生物细胞研究所提供。将欲冷冻保存的HL60细胞调整到良好的生长状态(对数生长期),随机数字表法分成4组,离心收集后在含体积分数为0.1小牛血清的RPMI-1640培养基中分别加入二甲基亚砜,使其终浓度依次为50,100,150,200g/L。冻存15d后,每组取1支冻存管复苏并接种于细胞培养板,培养12h后用锥虫蓝拒染法计算细胞复苏率。②选择冻存条件和冻存细胞密度相同的两支冻存管,按不同方法进行HL60细胞复苏。37℃水浴传统复苏法:立即将冻存管置于37℃水浴中,待融化后800r/min离心5min,吸去上清液,加入含体积分数为0.1小牛血清的RPMI-1640培养基,混匀后接种于细胞培养板,1mL/孔,9孔/组,置于体积分数为0.05的CO2培养箱37℃继续培养。40℃溶解后再37℃恒温改良复苏法:将冻存细胞于40℃水浴中迅速溶解,转入37℃水浴箱,融化后离心、加培养基等操作同传统复苏法。复苏细胞培养12h后采用锥虫蓝染色计算细胞存活率。③用无血清RPMI-1640培养基制备HL60细胞悬液,按3×107L-1密度接种于细胞培养板中,1mL/孔,然后分别加入体积分数为0.05,0.1,0.12,0.15,0.2的灭活小牛血清,每种血清浓度设置8个试验孔,并分别于培养12,24,36,48,60,72,84,96h后计数每孔细胞数量,并绘制细胞生长曲线。结果:①不同浓度二甲基亚砜冻存后HL60细胞复苏率的比较:二甲基亚砜200g/L组的细胞复苏率明显低于二甲基亚砜50,100,150g/L组[(64.6±2.8)%,(87.0±1.4)%,(86.4±2.1)%,(85.7±2.8)%;t=25.44,P<0.01],二甲基亚砜50,100,150g/L组间差异无显著性意义(t=0.82~1.44,P>0.05)。②不同复苏方法HL60细胞存活率的比较:与37℃水浴传统复苏法比较,40℃溶解后再37℃恒温改良复苏法的细胞存活率显著升高[(69.5±1.5)%,(87.4±1.8)%,t=23.24,P<0.01]。③RPMI-1640培养基不同血清含量对HL60细胞生长情况的影响:在体积分数为0.05的血清含量培养基中,HL60细胞基本不生长,且有逐渐死亡的趋势;在体积分数为0.1的血清含量培养基中,HL60细胞生长趋势明显,但生长速度相对较慢;在体积分数为0.12,0.15,0.2的血清含量培养基中,HL60细胞生长迅速,3种血清浓度间细胞生长趋势无明显差异。结论:以50g/L二甲基亚砜作为HL60细胞冻存保护剂、联合40℃溶解后再37℃恒温改良复苏法可使细胞保持最佳生物学特性,体积分数为0.12的血清含量为HL60细胞常规培养的最适浓度。 相似文献
42.
目的:利用免疫磁性细胞分选系统分离纯化骨髓衍生肝干细胞亚群c-Kit lin-。方法:实验于2006-07/08在南方医科大学实验动物中心完成。6~8周龄的SPF级纯系BALB/C雄性小鼠10只,体质量18~20g。收集小鼠股骨骨髓细胞,利用免疫磁性细胞分选系统,通过两步法分选纯化c-Kit lin-:将获取的lin-细胞悬液8℃条件下1500r/min离心10min,弃上清,按80μL/107加入Buffer重悬细胞。按20μL/107加生物素抗体磁珠,混匀,4℃冰箱孵育15min,按1mL/107加入Buffer洗细胞1次,8℃条件下1500r/min离心10min,弃上清,按500μL/108加入Buffer重悬细胞。Buffer500μL润MS柱,悬液过柱后,Buffer500μL/次洗柱3次,柱子脱离磁场,加1mLBuffer,用配套柱塞推出柱中的c-Kit lin-细胞,收集到c-kit lin-细胞,细胞计数。取2.0×106个细胞分成10等份,流式细胞仪分析c-Kit lin-细胞纯度,计算回收率,评估纯化效率,苔盼兰染色检测纯化前后的细胞活力。计算活细胞的百分率。细胞纯度和细胞回收率的计算:细胞纯度=分离产物中的阳性细胞数/分离细胞的总细胞数×100%,细胞回收率=分离产物中的阳性细胞数/起始标本阳性细胞总数×100%。结果:10只小鼠均进入结果分析。利用免疫磁性细胞分选系统分选出的骨髓衍生肝干细胞亚群c-Kit lin-细胞纯度和回收率分别为(77.98±2.34)%,75.40%,纯化前后细胞活力不受影响。结论:免疫磁性细胞分选系统能有效分选骨髓衍生肝干细胞亚群c-Kit lin-,纯度和回收率高,且不影响细胞活力。 相似文献
43.
Acute renal failure in Ghanaian children 总被引:1,自引:0,他引:1
D Adu Y Anim-Addo E D Yeboah J M Blankson S H Annobil 《Journal of tropical pediatrics》1984,30(1):36-39
44.
45.
Traditional or cultural practices in different parts of the world where oils are used continue to produce lipoid pneumonia. We report the ultrastructural findings and observations in animal fat associated lipoid pneumonia from two children following a cultural practice of forced feeding with animal fat (ghee). Clinical findings showed an acute or chronic chest infection which failed to respond to anti-microbial therapy. X-ray and chest CT scan revealed collapse/consolidations of the right middle and left lower lobes. Histology and electron microscopy revealed thickening and destruction of the alveolar septa, filling of alveolar spaces with red blood cells and macrophage which contained both primary and secondary lysosomes. The alveolar walls contained mostly type II pneumocyte with most of them surrounded by thickened basement membranes with only a small portion of their surfaces exposed directly to the alveolar space where it showed numerous microvilli. 相似文献
46.
Objective : Understanding patients' and their parents' perceptions towards asthma medication is important in developing strategies to ensure patient compliance. In this study, parents' perceptions towards their children's use of inhaled medication for asthma treatment were evaluated.
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
47.
Objective : To assess the relationship between the subtypes of hypertension in pregnancy and subsequent neonatal haematology.
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
48.
Bernard MY Cheung THY Au SY Chan CM Lam SH Lau RP Lee SF Lee WS Lo EHF Sin MY Tang HH Tsang 《Experimental & Clinical Cardiology》2005,10(1):21-24
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49.
Tan To Cheung Ronnie TP Poon Kenneth SH Chok Albert CY Chan Simon HY Tsang Wing Chiu Dai See Ching Chan Sheung Tat Fan Chung Mau Lo 《World journal of gastroenterology : WJG》2014,20(46):17448-17455
AIM: To analyze whether pancreaticoduodenectomy with simultaneous resection of tumor-involved vessels is a safe approach with acceptable patient survival.METHODS: Between January 2001 and March 2012, 136 patients received pancreaticoduodenectomy for adenocarcinoma at our hospital. Seventy-eight patients diagnosed with pancreatic head carcinoma were included in this study. Among them, 46 patients received standard pancreaticoduodenectomy (group 1) and 32 patients received pancreaticoduodenectomy with simultaneous resection of the portal vein or the superior mesenteric vein or artery (group 2) followed by reconstruction. The immediate surgical outcomes and survivals were compared between the groups. Fifty-five patients with unresectable adenocarcinoma of the pancreas without liver metastasis who received only bypass operations (group 3) were selected for additional survival comparison.RESULTS: The median ages of patients were 67 years (range: 37-82 years) in group 1, and 63 years (range: 35-86 years) in group 2. All group 2 patients had resection of the portal vein or the superior mesenteric vein and three patients had resection of the superior mesenteric artery. The pancreatic fistula formation rate was 21.7% (10/46) in group 1 and 15.6% (5/32) in group 2 (P = 0.662). Two hospital deaths (4.3%) occurred in group 1 and one hospital death (3.1%) occurred in group 2 (P = 0.641). The one-year, three-year and five-year overall survival rates in group 1 were 71.1%, 23.6% and 13.5%, respectively. The corresponding rates in group 2 were 70.6%, 33.3% and 22.2% (P = 0.815). The one-year survival rate in group 3 was 13.8%. Pancreaticoduodenectomy with simultaneous vascular resection was safe for pancreatic head adenocarcinoma.CONCLUSION: The short-term and survival outcomes with simultaneous resection were not compromised when compared with that of standard pancreaticoduodenectomy. 相似文献
50.
Aim: Findings of hypoxia prior to death and involvement of a dysregulation of the serotonergic network in sudden infant death syndrome (SIDS) may indicate that brain‐derived neutrophic factor (BDNF) also is of importance with regard to sudden unexpected infant death. Based on this, the purpose of this study was to investigate the BDNF val66met polymorphism in SIDS cases, cases of infectious death and controls. Methods: The polymorphism was investigated in 163 SIDS cases, 34 cases of infectious death and 121 controls, using real‐time PCR and fluorescence melting curve analysis. Results: There were no differences in val66met genotype distribution between neither the SIDS cases nor the cases of infectious death and controls (p = 0.95 and p = 0.52, respectively). Conclusion: The study indicates that the val66met polymorphism is not important for sudden unexpected infant death. However, several other SNPs in the BDNF gene, as well as in other genes involved in this pathway, including G‐protein, have to be investigated to fully exclude any involvement of BDNF in SIDS. 相似文献