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41.
小鼠皮肤超氧化物歧化酶活性与枸杞多糖的干预 总被引:1,自引:0,他引:1
目的:观察枸杞多糖对皮肤胶原代谢和自由基产生的影响,探讨其抗皮肤衰老的作用。方法:实验于2005-06/2006-05在广东医学院整形外科研究所完成。①实验材料:清洁级昆明小鼠60只,月龄2个月,体质量16~24g,雌雄各半。②实验分组:将小鼠随机分为正常对照组、衰老模型组和抗衰老模型组,每组20只。③实验干预:模型组每日用D-半乳糖溶液皮下注射制造衰老模型,用量和时间为80mg/(kg·d)7d,120mg/(kg·d)14d,140mg/(kg·d)14d,180mg/(kg·d)7d。正常对照组每日注射同体积的生理盐水。抗衰老模型组在注射D-半乳糖期间以枸杞多糖灌胃,剂量为20mg/(kg·d),正常对照组和衰老组则以同体积的生理盐水代之灌胃。④实验评估:42d后切取小鼠颈背部皮肤,测定超氧化物歧化酶活力、羟脯氨酸和丙二醛含量。结果:56只小鼠进入结果分析(4只死亡)。①小鼠皮肤超氧化物歧化酶活力:与正常对照组相比,衰老组和抗衰老组小鼠皮肤超氧化物歧化酶活力降低,差异有显著性意义(P<0.01);抗衰老组与衰老模型组比较,超氧化物歧化酶活力增加,差异有显著性意义(P<0.01)。②与正常对照组相比,衰老组和抗衰老组小鼠皮肤羟脯氨酸和丙二醛含量增加,差异有显著性意义(P<0.01);抗衰老组与衰老组比较,羟脯氨酸和丙二醛含量均降低,差异有显著性意义(P<0.01)。结论:枸杞多糖改善皮肤老化的作用与提高小鼠皮肤超氧化物歧化酶活力,降低羟脯氨酸、丙二醛含量,影响胶原代谢有关。 相似文献
42.
Efficient gene delivery to multipotential hematopoietic stem cells would greatly facilitate the development of effective gene therapy for certain hematopoietic disorders. We have recently described a rapid multiparameter sorting procedure for significantly enriching stem cells with competitive long-term lymphomyeloid repopulating ability (CRU) from 5-fluorouracil (5-FU)-treated mouse bone marrow. The sorted cells have now been tested as targets for retrovirus-mediated delivery of a marker gene, NeoR. They were cocultured for 4 days with fibroblasts producing a high titer of retrovirus in medium containing combinations of the hematopoietic growth factors interleukin-3 (IL-3), IL-6, c-kit ligand (KL), and leukemia inhibitory factor (LIF) and then injected into lethally irradiated recipients, together with sufficient "compromised" bone marrow cells to provide short-term support. Over 80% of the transplanted mice displayed high levels (> or = 20%) of donor- derived leukocytes when analyzed 4 to 6 months later. Proviral DNA was detected in 87% of these animals and, in half of them, the majority of the hematopoietic cells were marked. Thus, infection of the stem cells was most effective. The tissue and cellular distribution of greater than 100 unique clones in 55 mice showed that most sorted stem cells had lymphoid as well as myeloid repopulating potential. Secondary transplantation provided strong evidence for infection of very primitive stem cells because, in several instances, different secondary recipients displayed in their marrow, spleen, thymus and day 14 spleen colony-forming cells the same proviral integration pattern as the primary recipient. Neither primary engraftment nor marking efficiency varied for stem cells cultured in IL-3 + IL-6, IL-3 + IL-6 + KL, IL-3 + IL-6 + LIF, or all four factors, but those cultured in IL-3 + IL-6 + LIF appeared to have lower secondary engraftment potential. Provirus expression was detected in 72% of the strongly marked mice, albeit often at low levels. Highly efficient retroviral marking of purified lymphomyeloid repopulating stem cells should enhance studies of stem cell biology and facilitate analysis of genes controlling hematopoietic differentiation and transformation. 相似文献
43.
Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model 下载免费PDF全文
44.
45.
DIFFUSE IDIOPATHIC SKELETAL HYPEROSTOSIS (DISH) OF THE SPINE: A CAUSE OF BACK PAIN? A CONTROLLED STUDY 总被引:1,自引:0,他引:1
SCHLAPBACH P.; BEYELER CH.; GERBER N. J.; VAN DER LINDEN SJ.; BURGI U.; FUCHS W. A.; EHRENGRUBER H. 《Rheumatology (Oxford, England)》1989,28(4):299-303
This is the first controlled study of the frequency of backpain in a European caucasian population with diffuse idiopathicskeletal hyperostosis (DISH). Elderly patients admitted to hospital for reasons other thanback pain were assessed for the presence of spinal DISH usingthe routine lateral chest radiograph films. A total of 106 probands(82 males, 24 females) with a mean age of 70 years fulfilledthe criteria for DISH as defined previously. One hundred andseventyeight patients (117 males, 61 females) not meeting thesecriteria were used as controls. The prevalence of back painwas assessed by a blinded interviewer using a structured questionnaire.Our primary hymthesis was that spinal DISH positive probandshad not had back pain more often than controls. The controlledstudy showed no statistically significant difference in painfrequency between spinal DISH positive probands and controlsat any spinal level. We conclude that back pain does not occur more often in radiographicallydefined DISH positive probands than in controls. The radiologicalfinding of spinal DISH, as far as it does not lead to stenosisof the spinal canal or dysphagia, thus seems to be a findingwithout clinical relevance. KEY WORDS: Spine, Radiographs, Pain, Osteoarthritis, Forestier's disease, Ankylosing vertebral hyperostosis 相似文献
46.
目的:观察差速贴壁技术对星形胶质细胞纯化率的影响,旨在建立一套可靠的大鼠脑皮质星形胶质细胞的取材分离、纯化培养技术。方法:实验于2006-06/08在泰山医学院生命科学研究所完成。实验材料:出生2~3d的Wistar大鼠,雌雄不拘,由泰山医学院生命科学研究所实验动物中心提供。实验方法:选用出生二三天的Wistar大鼠进行脑皮质星形胶质细胞原代培养。实验分两组培养:常规培养组和差速贴壁培养组。差速贴壁培养组分别于15,30min取出,轻轻翻转培养瓶,将上清液移至另一培养瓶中,放入培养箱中继续培养。7~10d后传代,待细胞分层生长后,置于37℃摇床中250r/min振荡18h,倒掉上清液,D-Hank’s液洗3次后,加入0.25%胰酶消化,倒置显微镜下观察,待细胞突起回缩后加入含血清的培养基终止消化,用吸管反复吹打使细胞从瓶壁上脱落,细胞悬液1000r/min离心5min后,弃上清液,加入含体积分数为0.2血清的DMEM培养基混悬沉淀,接种入预先涂有L-多聚赖氨酸的培养瓶中继续培养。采用双重免疫荧光法鉴定星形胶质细胞纯度,测定积分吸光度值判断星形胶质细胞的生长状况。结果:①应用差速贴壁技术培养星形胶质细胞可明显提高星形胶质细胞纯度[常规培养组:(82±3)%,差速贴壁培养组15min:(94±2)%,差速贴壁培养组30min:(95±2)%,P<0.01]。差速贴壁需要充分的时间,15min组和30min组在提高星形胶质细胞纯度方面无明显差别。②差速贴壁培养组星形胶质细胞积分吸光度值高于常规培养组(常规培养组:528±25,差速贴壁培养组15min:972±17,差速贴壁培养组30min:996±35,P<0.05)。结论:①差速贴壁技术可明显提高星形胶质细胞纯化度,并且星形胶质细胞生长状态明显优于常规培养方法。②最佳差速贴壁时间为15min,过长差速贴壁时间对提高星形胶质细胞纯度无明显影响。 相似文献
47.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
48.
Queenan JT Jr; Veeck LL; Toner JP; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(7):1573-1576
In-vitro fertilization patients (n = 15) at risk of ovarian
hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day
of human chorionic gonadotrophin administration and 25 or more follicles of
intermediate or large size) underwent aspiration of all follicles and
cryopreservation of all fertilized oocytes at the pronuclear stage.
Patients were monitored for up to 2 weeks post- retrieval. Subsequent
transfer of cryopreserved-thawed embryos was performed in programmed cycles
using exogenous oestrogen and progesterone for endometrial preparation. Two
patients (13%) developed OHSS necessitating hospitalization and vaginal
aspiration of ascitic fluid. Two other patients (13%) developed moderate
OHSS requiring ascitic fluid vaginal aspiration in the office setting, with
dramatic improvement of the condition. Subsequent transfer of
cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per
transfer and ongoing or delivery rates of 42 and 67% per transfer and per
patient respectively. By eliminating pregnancy potential with
cryopreservation of all prezygotes and examining the pregnancy potential
with subsequent cryopreserved-thawed transfers, it is concluded that OHSS
is reduced, but not eliminated for patients at risk. Subsequent transfer of
cryopreserved-thawed prezygotes in a programmed cycle with exogenous
steroids yields an excellent pregnancy rate.
相似文献
49.
Soubhagya R. Nayak Ashwin Krishnamurthy SJ Madhan Kumar Latha V. Prabhu Bhagath Kumar Potu Sujatha D’Costa Anu Vinod Ranade 《Hand (New York, N.Y.)》2010,5(1):31-36
The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA)
can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar
artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation
of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal
tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation
of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed
to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed
with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the
RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm.
The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered
as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found
in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will
add to the existing knowledge of the vascular anatomy of forearm and hand. 相似文献
50.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献