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991.
Chen J Zhu Y Jiang Y Yu H Sun K Song W Luan L Lou K Li Y Jiang P Pang Q Hui R 《Human genetics》2012,131(7):1137-1143
Abnormalities in type III collagen in the arterial walls cause certain familial intracranial aneurysms (IAs); however, it remains unknown whether COL3A1 variants contribute to the risk of sporadic IAs. To study whether COL3A1 variants are associated with sporadic IAs, the association of COL3A1 variants with sporadic IAs was tested in 298 cases and 488 controls, replicated in an independent population of 192 cases and 1,690 controls, and further verified in 633 patients with intra-cerebral hemorrhage, 1,074 hypertensives, and 1,883 controls. We found that allele A of SNP rs1800255 conferred a 1.71-fold increased risk for IAs (adjusted odds ratio: OR = 1.71, 95% confidence interval: CI 1.19-2.45, P = 0.004) and results in an amino acid change of Ala698Thr, which led to a lower thermal stability of the peptide. These results were confirmed in the independent study. The associations were independent of the presence of hemorrhagic stroke and hypertension. These results support the view that the functional variant of COL3A1 is genetic risk factors for IAs in the Chinese population. 相似文献
992.
? Premise of the study: Microsatellite primers were developed and characterized for the long-lived tree species Platycladus orientalis for further investigation of its population characteristics. ? Methods and Results: Nine polymorphic microsatellites were identified for P. orientalis. The number of alleles per locus ranged from four to 22 (average = 11) for 94 individual specimens examined from four populations. The observed and expected heterozygosities ranged from 0.208 to 1.000 and 0.555 to 0.931, respectively. ? Conclusions: These nine markers can be used in future studies examining population genetics and the reproductive biology of P. orientalis, thereby revealing the importance of old-growth populations for the retention of genetic diversity, and providing useful insights into the maintenance of the potential genetic resource of this species. 相似文献
993.
In vivo detoxification of furfural by the oleaginous yeast, Trichosporon fermentans, under lipid-producing (i.e., nitrogen-limited) conditions was evaluated for the first time. During the initial fermentation phase, furfural was rapidly reduced to furfuryl alcohol, which is more toxic to T. fermentans than furfural. Furfuryl alcohol was subsequently oxidized to furoic acid which has low toxicity to T. fermentans and is the end product of the in vivo detoxification of furfural in this organism. These observations explain how T. fermentans can grow and accumulate lipids in medium containing furfural. They also indicate that strategies to minimize the transient production of furfuryl alcohol could further improve the capacity of the strain to produce lipids from furfural-containing lignocellulosic hydrolysates. 相似文献
994.
Peian Lou Yanan Zhu Peipei Chen Pan Zhang Jiaxi Yu Ning Zhang Na Chen Lei Zhang Hongmin Wu Jing Zhao 《BMC pulmonary medicine》2012,12(1):1-9
Background
While it is suggested that the prevalence of asthma in developed countries may have stabilized, this is not clear in currently developing countries. Current available information for both adults and children simultaneously on the burden and impact of allergic conditions in Colombia and in many Latin American countries is limited. The objectives of this study were to estimate the prevalence for asthma, allergic rhinitis (AR), atopic eczema (AE), and atopy in six colombian cities; to quantify costs to the patient and her/his family; and to determine levels of Immunoglobulin E (IgE) in asthmatic and healthy subjects.Methods
We conducted a cross-sectional, population-based study in six cities during the academic year 2009?C2010. We used a school-based design for subjects between 5?C17?years old. We carried out a community-based strategy for subjects between 1?C4?years old and adults between 18?C59?years old. Serum samples for total and antigen-specific (IgE) levels were collected using a population-based, nested, case?Ccontrol design.Results
We obtained information on 5978 subjects. The largest sample of subjects was collected in Bogotá (2392). The current prevalence of asthma symptoms was 12% (95% CI, 10.5-13.7), with 43% (95% CI, 36.3-49.2) reporting having required an emergency department visit or hospitalization in the past 12?months. Physician diagnosed asthma was 7% (95% CI, 6.1-8.0). The current prevalence of AR symptoms was 32% (95% CI, 29.5-33.9), and of AE symptoms was 14% (95% CI, 12.5-15.3). We collected blood samples from 855 subjects; 60.2% of asthmatics and 40.6% of controls could be classified as atopic.Conclusions
In Colombia, symptom prevalence for asthma, AR and AE, as well as levels of atopy, are substantial. Specifically for asthma, symptom severity and absence from work or study due to symptoms are important. These primary care sensitive conditions remain an unmet public health burden in developing countries such as Colombia. 相似文献995.
Expression of PRL3 (phosphatase of regenerating liver 3) protein was examined with immunohistochemistry in 60 cases of ESCC (oesophageal squamous cell carcinoma) with matched lymph node metastasis (n = 40) and 6 cases of oesophageal adenocarcinoma. Its associations with PRL1 and clinicopathological parameters were analysed. The results showed the frequency of PRL3 protein expression was significantly higher in ESCC (39/60, 65%) than in normal oesophageal mucosa (0/20, P < 0.001); higher in ESCC with lymph node metastasis (30/40, 75%) than in ESCC without lymph node metastasis (9/20, P = 0.022), as well as higher in metastatic ESCC in lymph node (38/40, 95%) than in the primary ESCC (39/60, 65%, P < 0.001). PRL3 was expressed in 1 out of 6 oesophageal adenocarcinomas, but showed no nuclear staining of PRL1. Expression of PRL3 protein was positively associated with the grade and partially with the stage of ESCC. These results suggest that expression of PRL3 protein may be involved in the metastasis of ESCC and serve as a biomarker for prediction of ESCC metastasis. 相似文献
996.
We address several conjectures raised in Cantrell et al. [Evolution of dispersal and ideal free distribution, Math. Biosci. Eng. 7 (2010), pp. 17-36 [ 9 ]] concerning the dynamics of a diffusion-advection-competition model for two competing species. A conditional dispersal strategy, which results in the ideal free distribution of a single population at equilibrium, was found in Cantrell et al. [ 9 ]. It was shown in [ 9 ] that this special dispersal strategy is a local evolutionarily stable strategy (ESS) when the random diffusion rates of the two species are equal, and here we show that it is a global ESS for arbitrary random diffusion rates. The conditions in [ 9 ] for the coexistence of two species are substantially improved. Finally, we show that this special dispersal strategy is not globally convergent stable for certain resource functions, in contrast with the result from [ 9 ], which roughly says that this dispersal strategy is globally convergent stable for any monotone resource function. 相似文献
997.
998.
Dong-Xiao Guo Xiao-Ning Wang Rong-Xiu Zhu Na Liu Jin-Chuan Zhou Wen-Tao Yu Hong-Xiang Lou 《Phytochemistry letters》2012,5(3):535-540
Three undescribed cis-clerodane lactones, scapanialides A–C (1–3), and a new cis-clerodane furano-diterpenoid, scaparvin F (4), were isolated from the Chinese liverwort Scapania parva Steph. Scapanialide B (2) is the first cis-clerodane diterpenoid with a bicyclo[5.4.0]undecane skeleton from liverworts. Their structures including the absolute configurations were determined by extensive analysis of multidimensional NMR spectroscopy and TDDFT CD calculations, together with crystal X-ray diffraction measurements. The cytotoxicity of compounds 1–4 was preliminary tested against the Hela and MCF-7 cell lines. 相似文献
999.
Zhao-Min Lin Li-Ning Wang Dong-Xiao Guo Xiao-Ning Wang Yong-Qing Liu Jin-Chuan Zhou Hong-Xiang Lou 《Phytochemistry letters》2012,5(3):510-513
A new dihydroisocoumarin derivative, R-(?)-heteroscyphide (1), together with three known terpenoid derivatives (2–4), were isolated from the liverwort Heteroscyphus coalitus. Their structures were elucidated by spectroscopic methods and the biogenetic pathway of compound 1 was proposed. Cytotoxic test revealed that they exhibited moderate inhibitory activity to three human tumor cell lines. 相似文献
1000.
Background: Nowadays it remains a controversial issue whether a correlation exists between the apoptosis rate of tumor tissue and the prognosis of the patients. The aim of the study is to investigate the relationships of apoptotic genes and apoptotic index of osteosarcoma tissue to prognosis of the patients, meanwhile to explore the valid prognostic biomarkers of osteosarcoma that will enhance efficacy of clinical treatments for osteosarcoma. Methods: In our studies, the immunohistochemical ABC and terminal DNA breakpoints in situ 3-hydroxy end labeling (TUNEL) techniques were used to detect the expressions of p53, c-MYC, BCL-2 and apoptotic index in 56 osteosarcoma specimens. The relationships between apoptotic genes expression and apoptotic index in osteosarcoma tissue and their correlations with pathologic classification and prognosis of osteosarcoma cases were analyzed. Results: We found that the expressions of p53, c-MYC, and BCL-2 were negatively correlated with apoptotic index of osteosarcoma tissue, were not correlated with pathological types of osteosarcoma, and were closely related to prognosis of the patients. Moreover, apoptotic index of osteosarcoma tissue was positively correlated with the long term survival of the patients. Conclusion: We concluded that the expressions of p53, c-MYC, BCL-2 protein and apoptotic index could be used as potential biomarks for predicting the progression and prognosis of osteosarcoma, and for optimizing clinical treatments. 相似文献