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131.

Background

An imbalance in Matrix MetalloProteases (MMPs) and Tissue Inhibitors of MMPs (TIMPs) contributes to Chronic Obstructive Pulmonary Disease (COPD) development. Longitudinal studies investigating Single Nucleotide Polymorphisms (SNPs) in MMPs and TIMPs with respect to COPD development and lung function decline in the general population are lacking.

Methods

We genotyped SNPs in MMP1 (G-1607GG), MMP2 (-1306 C/T), MMP9 (3 tagging SNPs), MMP12 (A-82G and Asn357Ser) and TIMP1 (Phe124Phe and Ile158Ile) in 1390 Caucasians with multiple FEV1 measurements from a prospective cohort study in the general population. FEV1 decline was analyzed using linear mixed effect models adjusted for confounders. Analyses of the X-chromosomal TIMP1 gene were stratified according to sex. All significant associations were repeated in an independent general population cohort (n = 1152).

Results

MMP2 -1306 TT genotype carriers had excess FEV1 decline (-4.0 ml/yr, p = 0.03) compared to wild type carriers. TIMP1 Ile158Ile predicted significant excess FEV1 decline in both males and females. TIMP1 Phe124Phe predicted significant excess FEV1 decline in males only, which was replicated (p = 0.10) in the second cohort. The MMP2 and TIMP1 Ile158Ile associations were not replicated. Although power was limited, we did not find associations with COPD development.

Conclusions

We for the first time show that TIMP1 Phe124Phe contributes to excess FEV1 decline in two independent prospective cohorts, albeit not quite reaching conventional statistical significance in the replication cohort. SNPs in MMPs evidently do not contribute to FEV1 decline in the general population.  相似文献   
132.
研究了低剂量辐照、抗氧化剂、包装条件以及贮藏时间等影响辐照冷却肉脂肪氧化的主要因素和抑制效果.结果表明,对冷却猪肉的辐照处理会加剧其脂肪的氧化,真空包装或无氧包装可以明显的降低贮藏期间辐照冷却肉的脂肪氧化.辐照处理前在肉糜中添加抗氧化剂并采用真空包装时, 肉糜可以贮藏2周以上而不产生脂肪氧化.比较几种主要的抗氧化剂的效果表明,茶多酚在抑制辐照冷却肉糜脂肪氧化方面效果最好.  相似文献   
133.
Fate and turnover rate of ovarian follicular cysts in dairy cattle   总被引:2,自引:0,他引:2  
Non-lactating, multiparous dairy cows diagnosed as having cysts by palpation per rectum were used. Cysts were induced with oestradiol-17 beta (15 mg) and progesterone (37.5 mg) dissolved in ethanol and injected s.c. twice daily for 7 days. Following initial diagnosis of cysts, ovaries were exposed by midventral laparotomy, and the perimeter of the base of each cyst was marked with subepithelial injections of charcoal. Ovaries were removed from cows by transvaginal incision at 10 days (Group 1; N = 8), 20 days (Group 2; N = 8), or 40 days (Group 3; N = 7) after marking of cysts. Ovaries were examined for structures present and their relationship to the marked site. Corpora lutea with ovulation papilla were present in 7/23 cows (1/8, 4/8 and 2/7, for Groups 1, 2 and 3, respectively). In these 7 cows, corpora lutea were at a site different from the original structure that was marked. Marked structures persisted for the duration of the experimental period in 1 and 2 cows, in Groups 1 and 3, respectively. In the remaining 13 cows, new large follicular structures (cysts) were present at a site other than that marked with charcoal. These structures developed on the ovary contralateral to the one originally marked in 9 of 13 cows. Cysts are therefore dynamic in nature and may persist or may be replaced by others.  相似文献   
134.
HA, C. O., SANDS, V. E., SOEPADMO, E. & JONG, K., 1988. Reproductive patterns of selected understorey trees in the Malaysian raia forest: the apomictic species. Garcinia is the predominant representative of the Clusiaceae in the understorey of the lowland rain forest of Peninsular Malaysia. In Pasoh Forest Reserve the dioecious species G. paruifolia was investigated since no male trees, but only trees with structurally hermaphodite flowers which later set fruit, were found there. Pollination and embryological studies indicated a condition of non-pseudogamous agamospermy, with no viable pollen grains being formed in the staminodes, and the unfertilized egg cell giving rise to the embryo. Supportive studies were made of microspore development in G. forbesi , and of embryogenesis and seed development in G. malaccensis and G. scortechinii which also appear to be agamospermous. The role of either facultative or obligate apomixis in gene fixation in these dioecious species is discussed, and the possible adaptive significance of reproductive versatility among certain rain forest trees is examined.  相似文献   
135.
Twenty lactating Holstein and Guernsey cows, diagnosed by rectal palpation as having ovarian cysts, were randomly divided within breed into two groups to receive either a single intramuscular injection of 100 μg of synthetic gonadotropin releasing hormone (GnRH) or an intravenous injection of 10,000 IU of human chorionic gonadotropin (HCG). The objective was to compare hormonal and clinical changes in cows with ovarian cysts following treatment with GnRH and HCG. Eight of ten and nine of ten cows given either GnRH and HCG, respectively, responded to treatment and subsequent fertility was not different between the two groups. Pre-injection plasma levels of LH, progesterone, and estradiol were highly variable. Mean plasma levels of LH, progesterone and estradiol did not differ between groups either following treatment (days 1–17 post-treatment), at the subsequent estrus, or during days 1–13 following the subsequent estrus. Mean LH levels did not differ significantly on the days either post-treatment or post-estrus except that levels were higher (P < .01) at the subsequent estrus as compared to the other days. Mean progesterone levels increased after treatment with either GnRH or HCG and were higher on days 5, 9 and 13 post-estrus and post-treatment as compared to the subsequent estrus. Mean levels of estradiol were higher (P < .05) at the subsequent estrus than any other time post-treatment or post-estrus. No other days were significantly different. In conclusion, GnRH and HCG are effective treatments for ovarian cysts in cattle. Endocrine response on days following treatment are similar for both compounds.  相似文献   
136.
Undifferentiated callus derived from asparagus protoplast cultureshas been used for studies on organogenesis. Root and shoot formationhas been obtained with different hormonal balances. Adeninehas been found to be effective, together with a cytokinin, inpromoting the formation of somatic embryoids in this tissue.  相似文献   
137.
Plants traditionally used to dye carpets and woven matting in the eastern Mediterranean region were investigated. The survey was carried out in Kadirli, Feke, Aladağ, the surrounding villages of Adana, and in Osmaniye (Turkey). According to the survey results, 37 species of plants belonging to 29 families were used in natural dye production. The total dye contents of collected plants ranged from 1.5% to 10.0%. Mordants and dyes obtained from some of these plants were used to treat wool yarn and the yarn's dyed properties were tested. Some of the plants were also examined in terms of cultivation and fifteen were transferred to a Dye Plants Collection Garden. They were Alnus glutinosa (L.) Gaertn. ssp. antitaurica Yalt., Arctium minus ssp. pubens (Bab.) Arènes, Chrysanthemum segetum L., Cistus creticus L., Cotinus coggygria Scop., Datisca cannabina L., Galium verum ssp. glabrescens Ehrend., Isatis tinctoria ssp. tomentella (Boiss. & Balansa) P.H.Davis, Melissa officinalis ssp. inodora Bornm., Mentha longifolia (L.) Huds. ssp. longifolia , Reseda lutea var. lutea L., Rhamnus oleoides ssp. graecus (Boiss. & Reut.) Holmboe, Rhus coriaria L., Rubia tinctorum L., and Rumex patientia L.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 71–77.  相似文献   
138.
沙柳灌丛植株形态与气流结构野外观测研究   总被引:12,自引:0,他引:12  
王蕾  王志  刘连友  哈斯 《应用生态学报》2005,16(11):2007-2011
通过野外观测,研究了毛乌素沙地南缘平沙地人工栽种单行沙柳灌丛的植株形态与气流结构.结果表明,沙柳灌能降低迎风侧和背风侧的近地面风速,使沙粒在植株下部沉积.积沙体积(V2)与植株体积(V1)相关性较高(R=0.696).单行沙柳灌丛在4 m高处风速为6 m·s-1时的气流结构特征为:迎风侧3H处风速已降低,2 H处风速又得到加强,之后在背风侧迅速降低,1 H处达到最低值,然后逐渐恢复到旷野风速.防护距离约为17H',有效防护距离约为13 H'.沙柳灌丛对植株高度以上高度处风速影响较小.  相似文献   
139.
动物实验人员的素质是决定医院动物实验工作质量的重要因素.但通常被忽视。随着动物实验标准化进程的不断推进,提高动物实验工作人员的素质、增强专业技能就显得尤为重要。本文结合我院实践主要阐述综合性医院动物实验工作的特点、对动物实验工作人员基本素质的要求以及培养和提高的途径。  相似文献   
140.
Used the random sampling and recommendation, 30 households of Mongolian in Horqin Juun Garon Country were selected to compare with 10 households of Han nationality which lives in the region of nearby. Forty sampling plots of homegardens were investigated. The results indicates that the perpendicular structure of homegarden plants in Mongolian and Han nationality can be classified to 0-1m, 1-2m, 2-5m, 5-10m, and higher than 10m. The perpendicular structure lower than 5m is predominance in both large and small homegardens. Comparing the cultivation pattern in two nationality, Mongolia still stay in the level of vegetable cultivation which relaled to the daily life, the plants for view and admire are very few at present. But Han nationality have started attaching importance to the view and admire homegarden plants. Besides, this research applied the software MVSP to analyze the type of homegardens and indacates that the homegarden of Mongolian in Horqin Juun Garon Country have four categories, and Han nationality have three categories. The results indicate that there are many differences between Mongolian and Han nationality. This is caused by the differences between the two nationalities in traditional farming culture, animal husbandry culture, the area of homegarden, the history of homegarden, the management of homegarden, and the traditional botanical knowledge on plant species utilization.  相似文献   
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