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111.
Lu SS Yau ST 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(1):80-82
This note answers some questions on holomorphic curves and their distribution in an algebraic surface of positive index. More specifically, we exploit the existence of natural negatively curved "pseudo-Finsler" metrics on a surface S of general type whose Chern numbers satisfy c(2)1>2c2 to show that a holomorphic map of a Riemann surface to S whose image is not in any rational or elliptic curve must satisfy a distance decreasing property with respect to these metrics. We show as a consequence that such a map extends over isolated punctures. So assuming that the Riemann surface is obtained from a compact one of genus q by removing a finite number of points, then the map is actually algebraic and defines a compact holomorphic curve in S. Furthermore, the degree of the curve with respect to a fixed polarization is shown to be bounded above by a multiple of q - 1 irrespective of the map. 相似文献
112.
Mather JN Yau SS 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(10):5946-5947
Two germs of complex analytic hypersurfaces with isolated singularities are biholomorphically equivalent if and only if they have the same dimension and their moduli algebras are isomorphic. 相似文献
113.
The effects of recombinant-DNA-derived interferons on the growth of myeloid progenitor cells 总被引:5,自引:0,他引:5
Interferons (IFNs) have been shown to have significant effects on hematopoietic cell growth. Previous studies defining these effects have utilized mouse and human alpha-, beta-, and gamma-IFN isolated from supernatants of stimulated cells. Despite purification, the possible presence of other lymphokines and soluble factors remains a concern. In this study, the effects of gene-cloned alpha- and gamma-IFN on colony- forming units of granulocyte/macrophage (CFU-GM) progenitors cultured from the peripheral blood of normal volunteers were examined. In addition, blast cell colonies from one patient with acute myelogenous leukemia (AML) were studied. The growth of normal CFU-GM and AML blast cell colonies was inhibited in a dose-dependent manner by gamma- and alpha-IFN. gamma-IFN was ten to 100 times more potent than alpha-IFN in that this species of IFN reduced colony formation by greater than 50% at concentrations of less than 15 antiviral U/mL. The effects of gamma- IFN were neutralized by a monoclonal antibody specific for gamma-IFN. These in vitro studies indicate that human gamma-IFN may be an important modulator of myelopoiesis. Although these data indicate a possible efficacy of gamma-IFN in the treatment of AML, the in vitro results should be considered for their in vivo significance. 相似文献
114.
Between 2001 and 2011, the standard of care for chronic hepatitis C virus (HCV) infection was a combination of pegylated interferon (PEGIFN) and ribavirin (RBV). In May 2011, boceprevir and telaprevir, two first-generation NS3/4A protease inhibitors, were approved in combination with PEG-IFN and RBV for 24 to 48 weeks in hepatitis C virus genotype 1 infections. In December 2013, simeprevir, a second-generation NS3/4A protease inhibitor, was approved for use with PEG-IFN and RBV for 12 weeks in genotype 1, while sofosbuvir, a NS5B nucleotide polymerase inhibitor, was approved for use with PEG-IFN and RBV for 12 weeks in genotypes 1 and 4, as well as with RBV alone for 12 weeks in genotype 2 and for 24 weeks in genotype 3. Sofosbuvir combined with simeprevir or an NS5A replication complex inhibitor (ledipasvir or daclatasvir) with or without RBV for 12 weeks in genotype 1 resulted in a sustained virological response >90%, irrespective of previous treatment history or presence of cirrhosis. Similarly impressive sustained virological response rates have been shown with ABT-450/r (ritonavir-boosted NS3/4A protease inhibitor)-based regimens in combination with other direct-acting antiviral agent(s) with or without RBV for 12 weeks in genotype 1. The optimal all-oral interferon-free antiviral regimen likely entails a combination of an NS5B nucleotide polymerase inhibitor with either a second-generation NS3/4A protease inhibitor or an NS5A replication complex inhibitor with or without RBV. Further research is needed to determine the role of resistance testing, clarify the optimal follow-up duration post-treatment, and evaluate the antiviral efficacy and safety in difficult-to-cure patient populations. 相似文献
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To clarify which hemodynamic measurement correlates best with lung mechanics in infants with congenital heart disease and left-to-right shunts, dynamic pulmonary function tests and echocardiography were performed in 26 infants with such disease (study infants) and in 37 normal, healthy infants (control infants). The tidal volume and pulmonary compliance (CL) were lower and airway resistance higher in infants with congenital heart disease than in control infants. A significant correlation was demonstrated between CL, expiratory resistance (Re), and the right pulmonary artery-to-aortic size ratio (RPA/DAO). CL and Re also correlated well with the corrected acceleration time √RR ratio (ACT/√RR: ACT, acceleration time and RR: length of the cardiac cycle) of pulmonary flow velocity. Stepwise multiple regression analysis revealed that RPA/DAO correlated best with both CL and Re. It is concluded that infants with congenital heart disease and left-to-right shunts have lower lung compliance and higher expiratory airway resistance than normal children, and that RPA/DAO is the echocardiographic parameter that correlates best with the changes in lung mechanics. Pediatr Pulmonol. 1996; 21:42–47. © 1996 Wiley-Liss, Inc. 相似文献
118.
Hiu-Yin Lao Timothy Ting-Leung Ng Ryan Yik-Lam Wong Celia Sze-Ting Wong Lam-Kwong Lee Denise Sze-Hang Wong Chloe Toi-Mei Chan Stephanie Hoi-Ching Jim Jake Siu-Lun Leung Hazel Wing-Hei Lo Ivan Tak-Fai Wong Miranda Chong-Yee Yau Jimmy Yiu-Wing Lam Alan Ka-Lun Wu Gilman Kit-Hang Siu 《Journal of clinical microbiology》2022,60(1)
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Omicron was designated by the WHO as a VOC on 26 November 2021, only 4 days after its sequence was first submitted. However, the impact of Omicron on current antibodies and vaccines remains unknown and evaluations are still a few weeks away. We analysed the mutations in the Omicron variant against epitopes. In our database, 132 epitopes of the 120 antibodies are classified into five groups, namely NTD, RBD-1, RBD-2, RBD-3, and RBD-4. The Omicron mutations impact all epitopes in NTD, RBD-1, RBD-2, and RBD-3, with no antibody epitopes spared by these mutations. Only four out of 120 antibodies may confer full resistance to mutations in the Omicron spike, since all antibodies in these three groups contain one or more epitopes that are affected by these mutations. Of all antibodies under EUA, the neutralisation potential of Etesevimab, Bamlanivimab, Casirivimab, Imdevima, Cilgavimab, Tixagevimab, Sotrovimab, and Regdanvimab might be dampened to varying degrees. Our analysis suggests the impact of Omicron on current therapeutic antibodies by the Omicron spike mutations may also apply to current COVID-19 vaccines. 相似文献