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1.
Fibulin-5/DANCE is essential for elastogenesis in vivo.   总被引:19,自引:0,他引:19  
The elastic fibre system has a principal role in the structure and function of various types of organs that require elasticity, such as large arteries, lung and skin. Although elastic fibres are known to be composed of microfibril proteins (for example, fibrillins and latent transforming growth factor (TGF)-beta-binding proteins) and polymerized elastin, the mechanism of their assembly and development is not well understood. Here we report that fibulin-5 (also known as DANCE), a recently discovered integrin ligand, is an essential determinant of elastic fibre organization. fibulin-5-/- mice generated by gene targeting exhibit a severely disorganized elastic fibre system throughout the body. fibulin-5-/- mice survive to adulthood, but have a tortuous aorta with loss of compliance, severe emphysema, and loose skin (cutis laxa). These tissues contain fragmented elastin without an increase of elastase activity, indicating defective development of elastic fibres. Fibulin-5 interacts directly with elastic fibres in vitro, and serves as a ligand for cell surface integrins alphavbeta3, alphavbeta5 and alpha9beta1 through its amino-terminal domain. Thus, fibulin-5 may provide anchorage of elastic fibres to cells, thereby acting to stabilize and organize elastic fibres in the skin, lung and vasculature.  相似文献   
2.
Serum levels of testosterone, FSH, LH and prolactin were measured by RIA in patients with BPH (benign prostatic hypertrophy) and in control men. The testosterone concentrations in the BPH group were significantly lower than that of the control group. Serum concentrations of FSH, LH, prolactin and estradiol, did not differ significantly in the 2 groups.  相似文献   
3.
Summary Serum levels of testosterone, FSH, LH and prolactin were measured by RIA in patients with BPH (benign prostatic hypertrophy) and in control men. The testosterone concentrations in the BPH group were significantly lower than that of the control group. Serum concentrations of FSH, LH, prolactin and estradiol, did not differ significantly in the 2 groups.  相似文献   
4.
Summary The esterase electromorphs of tetra and hexaploid populations ofUrginea maritima show differences in both heat-sensitivity and geographical distribution. Its possible adaptative significance is discussed.  相似文献   
5.
Using an Affymetrix 10K SNP array to screen for gene copy number changes in breast cancer, we detected a single-gene amplification of the ESR1 gene, which encodes estrogen receptor alpha, at 6q25. A subsequent tissue microarray analysis of more than 2,000 clinical breast cancer samples showed ESR1 amplification in 20.6% of breast cancers. Ninety-nine percent of tumors with ESR1 amplification showed estrogen receptor protein overexpression, compared with 66.6% cancers without ESR1 amplification (P < 0.0001). In 175 women who had received adjuvant tamoxifen monotherapy, survival was significantly longer for women with cancer with ESR1 amplification than for women with estrogen receptor-expressing cancers without ESR1 amplification (P = 0.023). Notably, we also found ESR1 amplification in benign and precancerous breast diseases, suggesting that ESR1 amplification may be a common mechanism in proliferative breast disease and a very early genetic alteration in a large subset of breast cancers.  相似文献   
6.
Variation in FTO contributes to childhood obesity and severe adult obesity   总被引:18,自引:0,他引:18  
We identified a set of SNPs in the first intron of the FTO (fat mass and obesity associated) gene on chromosome 16q12.2 that is consistently strongly associated with early-onset and severe obesity in both adults and children of European ancestry with an experiment-wise P value of 1.67 x 10(-26) in 2,900 affected individuals and 5,100 controls. The at-risk haplotype yields a proportion of attributable risk of 22% for common obesity. We conclude that FTO contributes to human obesity and hence may be a target for subsequent functional analyses.  相似文献   
7.
Immunization of mice with subcellular fractions of C. fasciculata led to myocarditis and electrocardiographic alterations similar to those induced by immunization with T. cruzi, the etiological agent of Chagas' disease, suggesting the presence of similar cardiotoxic antigens in both trypanosomatid flagellates.  相似文献   
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9.
Zusammenfassung Natrium-Sulfanilat-Clearance kann bei Schafen und Ziegen nicht als Mass für die Glomerulumfiltration verwendet werden, da Natrium-Sulfanilat glomerulär filtriert und tubulär sezerniert wird.

Supported in part by M.S. Public Health Grant No. 5-SO 1 FR-0545-02.  相似文献   
10.
Haas J  Creamer W  Ruiz A 《Nature》2004,432(7020):1020-1023
The Norte Chico region on the coast of Peru north of Lima consists of four adjacent river valleys--Huaura, Supe, Pativilca and Fortaleza--in which archaeologists have been aware of a number of apparently early sites for more than 40 years (refs 1- 3). To clarify the early chronology in this region, we undertook fieldwork in 2002 and 2003 to determine the dates of occupation of sites in the Fortaleza and Pativilca valleys. Here we present 95 new radiocarbon dates from a sample of 13 of more than 20 large, early sites. These sites share certain basic characteristics, including large-scale monumental architecture, extensive residential architecture and a lack of ceramics. The 95 new dates confirm the emergence and development of a major cultural complex in this region during the Late Archaic period between 3000 and 1800 calibrated calendar years bc. The results help to redefine a broader understanding of the respective roles of agricultural and fishing economies in the beginnings of civilization in South America.  相似文献   
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