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471.
Graphs allowing interconversion between various physical chemical parameters are presented for five Artemia habitats in the western USA. Both the mean osmosity and its typical yearly range differ greatly among habitats. Consequently, Artemia populations provide an interesting opportunity to study physiological and life history adaptations to differing degrees of habitat stability.  相似文献   
472.
The new, presumably extinct species, Chrysothamnus pulchelloides, is formally described and illustrated. The plant materials came from Holocene packrat middens. Anatomical and phyletic relationships of the fossil species to extant taxa are discussed.  相似文献   
473.
An expression of Centaurium namophilum (Gentianaceae), long confused with C. exaltatum in the Great Basin of the western United States, is described and designated as var. nevadense. It may be separated from the Death Valley region endemic, var. namophilum, by its broader leaves, its diffuse corymbose cyme, the ultimate peduncles that are longer than the flowers, its medium to deep rose pink corolla, and its stamens that equal or exceed the style and are only slightly exserted from the corolla-tube. The var. nevadense occurs from eastern California to western Utah, and from southeastern Oregon and adjacent Idaho south to the northern Mojave Desert of southeastern California. Centaurium exaltatum may be distinguished from the new variety by its broader, more elliptical leaves, dichotomous peduncles, paler pink or bluish and generally four-merous flowers, shorter and more blunt corolla lobes, and a thicker, more included style and stigma.  相似文献   
474.
Reproduction in L. pyromelana infralabialis Tanner is reported. Eggs were measured and weighed and incubation time and hatching reported. Hatchlings were measured and weighed, and feeding was observed.  相似文献   
475.
The Black Hills of South Dakota and Wyoming are an insular mountain range completely surrounded by the Great Plains. The stonefly (Plecoptera) fauna of the Black Hills was surveyed and zoogeographic affinities examined. Twenty-seven species representing 22 genera and 6 families were found. Fifteen new state records for South Dakota and 2 for Wyoming are presented. Two species are removed from the South Dakota list. An analysis of the North American distribution of each species showed a strong relationship between the Black Hills and the Rocky Mountains, with much weaker relationships between the Black Hills and eastern and northern regions. Results of a logistic regression analysis comparing factors contributing to long-distance dispersal ability against presence/absence in the Black Hills were inconclusive. However, other evidence suggests that the Black Hills fauna is a result of expansion and subsequent vicariance of stonefly populations during Pleistocene climatic oscillations.  相似文献   
476.
Functional impairment of DNA damage response pathways leads to increased genomic instability. Here we describe the centrosomal protein CEP152 as a new regulator of genomic integrity and cellular response to DNA damage. Using homozygosity mapping and exome sequencing, we identified CEP152 mutations in Seckel syndrome and showed that impaired CEP152 function leads to accumulation of genomic defects resulting from replicative stress through enhanced activation of ATM signaling and increased H2AX phosphorylation.  相似文献   
477.
We tested 16 million SNPs, identified through whole-genome sequencing of 457 Icelanders, for association with gout and serum uric acid levels. Genotypes were imputed into 41,675 chip-genotyped Icelanders and their relatives, for effective sample sizes of 968 individuals with gout and 15,506 individuals for whom serum uric acid measurements were available. We identified a low-frequency missense variant (c.1580C>G) in ALDH16A1 associated with gout (OR = 3.12, P = 1.5 × 10(-16), at-risk allele frequency = 0.019) and serum uric acid levels (effect = 0.36 s.d., P = 4.5 × 10(-21)). We confirmed the association with gout by performing Sanger sequencing on 6,017 Icelanders. The association with gout was stronger in males relative to females. We also found a second variant on chromosome 1 associated with gout (OR = 1.92, P = 0.046, at-risk allele frequency = 0.986) and serum uric acid levels (effect = 0.48 s.d., P = 4.5 × 10(-16)). This variant is close to a common variant previously associated with serum uric acid levels. This work illustrates how whole-genome sequencing data allow the detection of associations between low-frequency variants and complex traits.  相似文献   
478.
We performed a genome-wide association study of melanoma in a discovery cohort of 2,168 Australian individuals with melanoma and 4,387 control individuals. In this discovery phase, we confirm several previously characterized melanoma-associated loci at MC1R, ASIP and MTAP-CDKN2A. We selected variants at nine loci for replication in three independent case-control studies (Europe: 2,804 subjects with melanoma, 7,618 control subjects; United States 1: 1,804 subjects with melanoma, 1,026 control subjects; United States 2: 585 subjects with melanoma, 6,500 control subjects). The combined meta-analysis of all case-control studies identified a new susceptibility locus at 1q21.3 (rs7412746, P = 9.0 × 10(-11), OR in combined replication cohorts of 0.89 (95% CI 0.85-0.95)). We also show evidence suggesting that melanoma associates with 1q42.12 (rs3219090, P = 9.3 × 10(-8)). The associated variants at the 1q21.3 locus span a region with ten genes, and plausible candidate genes for melanoma susceptibility include ARNT and SETDB1. Variants at the 1q21.3 locus do not seem to be associated with human pigmentation or measures of nevus density.  相似文献   
479.
Mutations affecting ciliary components cause ciliopathies. As described here, we investigated Tectonic1 (Tctn1), a regulator of mouse Hedgehog signaling, and found that it is essential for ciliogenesis in some, but not all, tissues. Cell types that do not require Tctn1 for ciliogenesis require it to localize select membrane-associated proteins to the cilium, including Arl13b, AC3, Smoothened and Pkd2. Tctn1 forms a complex with multiple ciliopathy proteins associated with Meckel and Joubert syndromes, including Mks1, Tmem216, Tmem67, Cep290, B9d1, Tctn2 and Cc2d2a. Components of this complex co-localize at the transition zone, a region between the basal body and ciliary axoneme. Like Tctn1, loss of Tctn2, Tmem67 or Cc2d2a causes tissue-specific defects in ciliogenesis and ciliary membrane composition. Consistent with a shared function for complex components, we identified a mutation in TCTN1 that causes Joubert syndrome. Thus, a transition zone complex of Meckel and Joubert syndrome proteins regulates ciliary assembly and trafficking, suggesting that transition zone dysfunction is the cause of these ciliopathies.  相似文献   
480.
A20 (TNFAIP3) is a protein that is involved in the negative feedback regulation of NF-κB signaling in response to specific proinflammatory stimuli in different cell types and has been suggested as a susceptibility gene for rheumatoid arthritis. To define the contribution of A20 to rheumatoid arthritis pathology, we generated myeloid-specific A20-deficient mice and show that specific ablation of Tnfaip3 in myeloid cells results in spontaneous development of a severe destructive polyarthritis with many features of rheumatoid arthritis. Myeloid-A20-deficient mice have high levels of inflammatory cytokines in their serum, consistent with a sustained NF-κB activation and higher TNF production by macrophages. Destructive polyarthritis in myeloid A20 knockout mice was TLR4-MyD88 and IL-6 dependent but was TNF independent. Myeloid A20 deficiency also promoted osteoclastogenesis in mice. Together, these observations indicate a critical and cell-specific function for A20 in the etiology of rheumatoid arthritis, supporting the idea of developing A20 modulatory drugs as cell-targeted therapies.  相似文献   
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