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101.
Vasoactive intestinal polypeptide secreting islet cell tumors (VIPomas) are neuroendocrine tumors that secrete excessive amounts of vasoactive intestinal polypeptide (VIP) that cause distinct syndromes characterized by large-volume diarrhea, hypokalemia, and dehydration. The annual incidence of these tumors is estimated to be about one per 10,000,000 individuals in the general population. We report a successful treatment of VIPoma with hepatic chemoembolization of a metastatic hepatic lesion evidenced by a reduction of VIP levels and resolutions of symptoms in a patient with pancreatic VIPoma unresponsive to increased doses of an octreotide analog.  相似文献   
102.

Introduction  

Inflammation is an important feature of many joint diseases, and levels of cartilage biomarkers measured in synovial fluid may be influenced by local inflammatory status. Little is known about the magnitude and time course of inflammation-induced changes in cartilage tissue turnover as measured in vivo by synovial fluid markers. We aimed to study temporal changes in concentrations of inflammatory mediators, matrix metalloproteinase activity and cartilage biomarkers over 1 week in joints with experimentally induced inflammation.  相似文献   
103.

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   
104.
1. It is widely acknowledged that sudden, large‐scale flood pulses are drivers of benthic and planktonic biodiversity change in floodplains. The impact of such pulses on pleuston (biotic communities associated with root systems of floating plants) remains to be demonstrated. Here, we investigate the effects of local and regional drivers on seasonal changes in abundance and diversity of ostracod communities in pleuston. 2. Temporal and spatial distribution patterns of species richness, abundance, diversity and evenness of ostracods associated with the floating water hyacinth, Eichhornia crassipes, in a lentic environment from the upper Paraná River floodplain, were investigated in relation to local, as well as regional, environmental factors. Ostracods were sampled monthly over an annual cycle (March 2004–February 2005). Twenty‐seven species were found, representing the families Cyprididae, Candonidae, Limnocytheridae and Darwinulidae. Both diversity and abundance of ostracod communities showed seasonal changes, although species turn‐over during the year was limited. 3. We tested two hypotheses concerning the causality of these fluctuations: seasonal recruitment and influx of allochthonous ostracods during the flood pulse. Our results indicate that seasonal recruitment is more likely to be the driver of fluctuations in relation to the flood pulse. We postulate that pleuston communities are buffered against possible detrimental effects of flood pulses.  相似文献   
105.
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   
106.
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   
107.
Mucins are synthesized and secreted by many epithelia. They are complex glycoproteins that offer cytoprotection. In their functional configuration, mucins form oligomers by a biosynthetic process that is poorly understood. A family of four human gastrointestinal mucin genes (MUC2, MUC5AC, MUC5B, and MUC6) is clustered to chromosome 11p15.5. To study oligomerization of these related mucins, we performed metabolic labeling experiments with [35S]amino acids in LS174T cells, and isolated mucin precursors by specific immunoprecipitations that were analyzed on SDS-PAGE. Each of the precursors of MUC2, MUC5AC, MUC5B, and MUC6 formed a single species of disulfide-linked homo-oligomer within 1 h after pulse labeling. Based on apparent molecular masses, these oligomeric precursors were most likely dimers. Inhibition of vesicular RER-to-Golgi transport, with brefeldin A and CCCP, did not affect the dimerization of MUC2 precursors, localizing dimerization to the RER. O-Glycosylation of MUC2 followed dimerization. Inhibition of N- glycosylation by tunicamycin retarded, but did not inhibit, dimerization, indicating that N-glycans play a role in efficient dimerization of MUC2 precursors. Based on sequence homology, the ability of MUC2, MUC5AC, MUC5B and MUC6 to dimerize most likely resides in their C-terminal domains. Thus, the RER-localized dimerization of secretory mucins likely proceeds by similar mechanisms, which is an essential step in the formation of the human gastrointestinal mucus- gels.   相似文献   
108.
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   
109.
麻黄蚜虫EphedraphisgobicaSzelegiewicz是危害中药材———草麻黄的重要害虫之一。通过室内饲养 ,构建了该蚜虫的实验种群生命表。结果表明 :该蚜虫的内禀增长率 (rm)、周限增长率 (λ)、净增殖率 (R0 )、种群世代平均周期 (T)和种群加倍时间 (t)分别是 :0 2 60 ,1 2 98,1 9 2 48,1 1 3 5 4和 2 661。  相似文献   
110.
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   
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