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511.
512.
The structure and function of lysozyme   总被引:1,自引:0,他引:1  
L N Johnson 《Science progress》1966,54(215):367-385
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513.
Summary Imidazole pyruvate was found to be a very potent natural chelating agent in reversing the inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+. This metabolite may play a physiological role in gluconeogenesis.This work was supported by grant RR-8006 from the General Research Branch, Division of Research Resources, NIH, USA.  相似文献   
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Summary Allotransplantation of fresh, 1 or 2 week cultured parathyroid glands from Wistar rats (AgB2) to Fischer rats (AgB1) resulted in prompt rejection of the transplant in the muscle site; whereas transplantation into the adrenal site offered slightly prolonged survival, suggesting that the latter is a privileged transplantation site.Acknowledgments. The authors thank Mrs Barbara Lovett for her secretarial assistance.  相似文献   
516.
Cerebello-oculo-renal syndrome (CORS), also called Joubert syndrome type B, and Meckel (MKS) syndrome belong to the group of developmental autosomal recessive disorders that are associated with primary cilium dysfunction. Using SNP mapping, we identified missense and truncating mutations in RPGRIP1L (KIAA1005) in both CORS and MKS, and we show that inactivation of the mouse ortholog Rpgrip1l (Ftm) recapitulates the cerebral, renal and hepatic defects of CORS and MKS. In addition, we show that RPGRIP1L colocalizes at the basal body and centrosomes with the protein products of both NPHP6 and NPHP4, known genes associated with MKS, CORS and nephronophthisis (a related renal disorder and ciliopathy). In addition, the RPGRIP1L missense mutations found in CORS individuals diminishes the interaction between RPGRIP1L and nephrocystin-4. Our findings show that mutations in RPGRIP1L can cause the multiorgan phenotypic abnormalities found in CORS or MKS, which therefore represent a continuum of the same underlying disorder.  相似文献   
517.
To identify risk variants for multiple myeloma, we conducted a genome-wide association study of 1,675 individuals with multiple myeloma and 5,903 control subjects. We identified risk loci for multiple myeloma at 3p22.1 (rs1052501 in ULK4; odds ratio (OR) = 1.32; P = 7.47 × 10(-9)) and 7p15.3 (rs4487645, OR = 1.38; P = 3.33 × 10(-15)). In addition, we observed a promising association at 2p23.3 (rs6746082, OR = 1.29; P = 1.22 × 10(-7)). Our study identifies new genomic regions associated with multiple myeloma risk that may lead to new etiological insights.  相似文献   
518.
Gibbons M  Johnson C 《Nature》1970,227(5254):125-127
Do economic advances spring directly from fundamental scientific discoveries? The early history of the transistor suggests that the situation is not nearly so simple as this.  相似文献   
519.
Based on 5 high-precision ^230Th dates and 103 stable oxygen isotope ratios (51eO) obtained from the top 16 mm of a stalagmite collected from Wanxiang Cave, Wudu, Gansu, variation of monsoonal precipitation in the modern Asian Monsoon (AM) marginal zone over the past 100 years was reconstructed. Comparison of the speleothem δ^18O record with instrumental precipitation data at Wudu in the past 50 years indicates a high parallelism between the two curves, suggesting that the speleothem δ^18O is a good proxy for the AM strength and associated precipitation, controlled by "amount effect" of the precipitation. Variation of the monsoonal precipitation during the past 100 years can be divided into three stages, increasing from AD 1875 to 1900, then decreasing from AD 1901 to 1946, and increasing again thereafter. This variation is quite similar to that of the Drought/Flooding index archived from Chinese historical documents. This speleothem-derived AM record shows a close association with the Pacific Decadal Oscillation (PDO) between AD 1875 and 1977, with higher monsoonal precipitation corresponding to cold PDO phase and vice versa at decadal timescale. The monsoonal precipitation variation is out of phase with the PDO after AD 1977, probably resulting from the decadal climate jump in the north Pacific occurring at around AD 1976/77. These results demonstrate a strong linkage between the AM and associated precipitation and the Pacific Ocean via ocean/atmosphere interaction. This relationship will aid to forecast future hydrological cycle for the AM monsoon region, and to improve forecasting potential of climatic model with observation data from cave.  相似文献   
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