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61.
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
62.
63.
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
64.
Summary The purpose of this study was to evaluate the occurrence of superficial flaws after machining and to identify fracture initiation and propagation in three‐unit heat‐treated machined fixed partial dentures (FPDs) substructures made of hot isostatic pressed (HIPed) yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) after loaded to fracture. Four three‐unit HIPed Y‐TZP‐based FPDs substructures were examined. To evaluate the occurrence of superficial flaws after machining, the surfaces were studied utilizing a fluorescent penetrant method. After static loading to fracture, characteristic fracture features on both mating halves of the fractured specimens were studied using a stereomicroscope and a scanning electron microscope. Grinding grooves were clearly visible on the surfaces of the machined FPDs substructures, but no other flaws could be seen with the fluorescent penetrant method. After loading to fracture, the characteristic fracture features of arrest lines, compression curl, fracture mirror, fracture origin, hackle and twist hackle were detected. These findings indicated that the decisive fracture was initiated at the gingival embrasure of the pontic in association with a grinding groove. Thus, in three‐unit heat‐treated machined HIPed Y‐TZP FPDs substructures, with the shape studied in this study, the gingival embrasure of the pontic seems to be a weak area providing a location for tensile stresses when they are occlusally loaded. In this area, fracture initiation may be located to a grinding groove. 相似文献
65.
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
66.
Localization of immunoglobulin-containing cells in human endometrium in the first trimester of pregnancy and throughout the menstrual cycle 总被引:1,自引:0,他引:1
J N Bulmer S V Hagin C M Browne W D Billington 《European journal of obstetrics, gynecology, and reproductive biology》1986,23(1-2):31-44
The distribution of immunoglobulins in normal human endometrium throughout the menstrual cycle and in early pregnancy has been studied with an immunoperoxidase technique. In first-trimester decidua, IgG was detected within many cells of differing morphology and size. Large IgG-containing cells were often binucleate and were believed to be decidual cells. Examination of serial sections showed no kappa or lambda light-chain restriction, suggesting absorption of the immunoglobulin content. Medium-sized, irregular, IgG-containing cells were macrophages. An additional substantial population of small hyperchromatic IgG-containing cells were prominent around arterioles and adjacent to endometrial glands. From examination of adjacent sections stained with phloxine tartrazine, it was concluded that these represented endometrial granulocytes. Labelling for light chains again suggested absorption of the immunoglobulin content. In contrast, in non-pregnant endometrium immunoglobulin-containing stromal cells were uncommon, although IgG and IgA were detected in gland epithelium and secretions and in the stromal interstitium particularly in the secretory phase. These results support the notion that human endometrium lacks a classical secretory immune system and highlight the requirement for correlation between studies of cell surface markers, morphology and cell surface receptors. 相似文献
67.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics. 相似文献
68.
J N Bulmer W D Billington P M Johnson 《American journal of obstetrics and gynecology》1984,148(1):19-26
Three murine monoclonal antibodies (H315, H316, and NDOG1) have been used in a peroxidase-antiperoxidase technique on formalin-fixed paraffin-embedded tissues to identify populations of fetal trophoblast cells by their expression of membrane antigens in chorionic and decidual tissue from the first trimester of normal human pregnancy. H315 and H316 showed comparable staining of placental villous syncytiotrophoblast and cytotrophoblast and were also able to distinguish subpopulations of nonvillous trophoblast in the placental bed, including perivascular and endovascular trophoblastic cells as well as cytotrophoblastic elements within the decidua and myometrium. H315 and H316 also showed cytoplasmic staining of columnar epithelium of endometrial glands throughout the first trimester. In contrast, NDOG1 stained chorionic syncytiotrophoblast but not villous cytotrophoblast and also did not react with any cytotrophoblastic elements in the placental bed. NDOG1 distinguished these different subpopulations of trophoblast as early as 13 to 15 days after ovulation. 相似文献
69.
Recently, nicotinic acid adenine dinucleotide phosphate (NAADP) has been shown, using different techniques, to mobilize intracellular Ca2+ stores in invertebrate, lower vertebrate, plant and mammalian cells. This endogenous molecule might play an atypical role in Ca2+ signalling by coordinating the responses of other Ca2+-releasing messengers. Furthermore, radioligand binding experiments have provided an insight into how desensitization of the NAADP receptor might occur. 相似文献
70.
beta-Endorphin (beta-END) and alpha-melanocyte stimulating hormone (alpha-MSH), neuropeptides derived from proopiomelanocortin (POMC), have opposite effects on eating behavior. We injected rats with alpha-MSH (0.6 nmol) or beta-END (1 nmol) into the PVN (three times in a 26 h period). These doses of alpha-MSH and beta-END decreased and increased feeding respectively. Following alpha-MSH administration into the PVN, mRNA levels of POMC decreased by 17%, whereas there was no significant change in gene expression of either proDynorphin or proEnkephalin. PVN injection of beta-END failed to alter gene expression of POMC, proDynorphin or proEnkephalin. These data suggest that a feedback pathway exists between the PVN and ARC for alpha-MSH and POMC, but not for beta-END and POMC. 相似文献