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61.
Jugran Arun K. Joshi Ravindra K. Bhatt Indra D. Rawal Ranbeer S. Palni Lok Man S. 《Proceedings of the National Academy of Sciences, India. Section B.》2019,89(1):371-378
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - In light of the recent evidences that pollinators have a significant implication for maintenance of... 相似文献
62.
Shaohong Peng Pei Guo Xiao Lin Ying An Kong Hung Sze Matthew Ho Yan Lau Zhefan Stephen Chen Qianwen Wang Wen Li Jacquelyne Ka-Li Sun Sum Yi Ma Ting-Fung Chan Kwok-Fai Lau Jacky Chi Ki Ngo Kin Ming Kwan Chun-Ho Wong Sik Lok Lam Steven C. Zimmerman Tiziano Tuccinardi Zhong Zuo Ho Yu Au-Yeung Hei-Man Chow Ho Yin Edwin Chan 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(19)
63.
Wai CT Fontana RJ Polson J Hussain M Shakil AO Han SH Davern TJ Lee WM Lok AS;US Acute Liver Failure Study Group 《Journal of viral hepatitis》2005,12(2):192-198
The role of hepatitis B virus (HBV) genotypes in the outcome of acute HBV infection is unclear. In this study, we aimed to evaluate the clinical and virological features of patients with hepatitis B-related acute liver failure (HBV-ALF) in the US. Clinical and laboratory features of consecutive patients with HBV-ALF from the US ALF Study Group were analysed. Prevalence of HBV genotypes, precore stop (G1896A) and core promoter dual (T1762A, A1764T) variants among patients with HBV-ALF were compared with a cohort of 530 patients with chronic HBV infection. Thirty-four HBV-ALF patients were studied: mean age 41 years, 56% men, 25 had detectable HBV-DNA. HBV genotypes A, B, C and D were found in 36, 24, 8 and 32% patients, respectively. Precore stop and core promoter dual variants were detected in 32 and 44% of patients, respectively. Twenty-three (68%) patients survived: 14 after liver transplant, nine without transplant. Older age was the only independent factor associated with poor outcome. Compared with patients with chronic HBV infection, patients with ALF were more likely to be non-Asians (88% vs 44%, P = 0.005) and to have genotype D (32% vs 10%, P < 0.01). A higher prevalence of HBV genotype D persisted even after matching for race and HBeAg status (32% vs 16%, P = 0.007). We concluded that HBV genotype D was more frequently found in patients with HBV-ALF than those with chronic HBV infection in the US. Further studies are needed to determine if HBV genotypes play a role in the outcome of acute HBV infection. 相似文献
64.
Gamma-crystallin family of the mouse lens: structural and evolutionary relationships. 总被引:5,自引:1,他引:5
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M L Breitman S Lok G Wistow J Piatigorsky J A Tréton R J Gold L C Tsui 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(24):7762-7766
The heterogeneity inherent among gamma-crystallins of the mouse lens was investigated by sequence analysis of three gamma-crystallin-specific cDNAs. Comparison of the nucleotide sequence of these cDNAs and one previously reported by us revealed that the four gamma-cDNAs share 80-90% homology in nucleotide sequence. The entire 3' half of the coding region shows more variability than the 5' half, whereas the greatest variability is observed in the 3' untranslated region where numerous base substitutions, deletions, and insertions seem to have occurred. Alignment of the amino acid sequences of the four mouse gamma-crystallins according to the known four structural motifs of the major calf gamma-crystallin, gamma-II, suggests that all four mouse polypeptides are structurally very similar to calf gamma-II. However, most of the mouse polypeptides differ from gamma-II by the absence of one amino acid residue, resulting in a shorter connecting peptide between the two globular domains of the protein. Primary sequence alignment also revealed that the four mouse gamma-crystallins are most divergent in the third structural motif of the polypeptide. The significance of these differences in terms of the structure and function of the gamma-crystallins in the mouse lens is discussed. 相似文献
65.
Pont LG van Gilst WH Lok DJ Kragten HJ Haaijer-Ruskamp FM;Dutch Working Group on Heart Failure 《European journal of heart failure》2003,5(2):187-193
AIMS: Internationally, research indicates that pharmacotherapy for chronic heart failure (CHF) is sub-optimal. Traditionally, assessment of drug use in heart failure has focused on the use of individual agents irrespective of CHF severity. This study investigates drug use for CHF patients in general practice with respect to the available evidence, incorporating both disease severity and the use of combination drug regimes. METHODS AND RESULTS: A cross-sectional survey of 769 Dutch CHF patients was performed as part of IMPROVEMENT of HF study. For each New York Heart Association severity classification the minimum treatment appropriate for the heart failure severity according to the scientific evidence available at the time of the study (1999) was defined. The proportion of patients treated with each drug increased with increasing severity, with the exception of the beta-blockers. Patients with less severe heart failure were approximately four to eight times more likely to receive evidence-based treatment than those with more severe heart failure. DISCUSSION: To assess pharmacological treatment of heart failure, in relation to the available evidence, it is important to take severity into account. While the number of drugs prescribed increased with increasing severity, the use of evidence-based regimes was lower in patients with more severe heart failure. 相似文献
66.
Kuan Rong Chan Eugenia Z. Ong Hwee Cheng Tan Summer Li-Xin Zhang Qian Zhang Kin Fai Tang Nivashini Kaliaperumal Angeline Pei Chiew Lim Martin L. Hibberd Soh Ha Chan John E. Connolly Manoj N. Krishnan Shee Mei Lok Brendon J. Hanson Chao-Nan Lin Eng Eong Ooi 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(7):2722-2727
Viruses must evade the host innate defenses for replication and dengue is no exception. During secondary infection with a heterologous dengue virus (DENV) serotype, DENV is opsonized with sub- or nonneutralizing antibodies that enhance infection of monocytes, macrophages, and dendritic cells via the Fc-gamma receptor (FcγR), a process termed antibody-dependent enhancement of DENV infection. However, this enhancement of DENV infection is curious as cross-linking of activating FcγRs signals an early antiviral response by inducing the type-I IFN-stimulated genes (ISGs). Entry through activating FcγR would thus place DENV in an intracellular environment unfavorable for enhanced replication. Here we demonstrate that, to escape this antiviral response, antibody-opsonized DENV coligates leukocyte Ig-like receptor-B1 (LILRB1) to inhibit FcγR signaling for ISG expression. This immunoreceptor tyrosine-based inhibition motif-bearing receptor recruits Src homology phosphatase-1 to dephosphorylate spleen tyrosine kinase (Syk). As Syk is a key intermediate of FcγR signaling, LILRB1 coligation resulted in reduced ISG expression for enhanced DENV replication. Our findings suggest a unique mechanism for DENV to evade an early antiviral response for enhanced infection.Despite long-lived serotype-specific immunity upon initial infection, predicted global prevalence of dengue now surpasses World Health Organization estimates by more than threefold with 390 million cases annually (1). Furthermore, the risk of severe disease is augmented by cross-reactive or subneutralizing levels of antibody (2, 3), which opsonize dengue virus (DENV) to ligate Fc-gamma receptor (FcγR) for entry into monocytes, macrophages, and dendritic cells, a phenomenon known as antibody-dependent enhancement (ADE) of DENV infection (4, 5). The resultant greater viral burden leads to increased systemic inflammation that precipitates plasma leakage, a hallmark of dengue hemorrhagic fever (6). However, ligation of the activating FcγRs by immune complexes has been shown to induce type-I IFN stimulated genes (ISGs), independent of autocrine or paracrine IFN activity, unless the inhibitory FcγRIIB is coligated (7). We and others reported recently that coligation of FcγRIIB by DENV immune complexes requires high antibody concentration, and such coligation inhibited the entry of DENV immune complexes into monocytes (8, 9). At low antibody concentrations where ADE occurs, the inhibitory FcγRIIB is not coligated (9). Ligation of the activating FcγRs by DENV opsonized with subneutralizing levels of antibody would thus induce the expression of ISGs and hinder DENV replication (10). Here, we demonstrate that DENV employs a unique evasive mechanism by coligating LILRB1 to down-regulate the early antiviral responses triggered by activating FcγRs for ADE. 相似文献
67.
68.
Cone beam computed tomography is widely used in dentistry. Incidental findings are common, with many requiring intervention or monitoring. We present a rare case of previously undiagnosed, asymptomatic multiple myeloma first identified incidentally on cone beam computed tomography and panoramic radiography. This case highlights the diverse range of lesions that may appear on cone beam computed tomography and the importance of radiologic interpretation. 相似文献
69.
Agnes N Kiragga Judith J Lok Beverly S Musick Ronald J Bosch Ann Mwangi Kara K Wools-Kaloustian Constantin T Yiannoutsos for the East Africa IeDEA Regional Consortium 《Journal of the International AIDS Society》2014,17(1)
Objective
Estimates of CD4 response to antiretroviral therapy (ART) obtained by averaging data from patients in care, overestimate population CD4 response and treatment program effectiveness because they do not consider data from patients who are deceased or not in care. We use mathematical methods to assess and adjust for this bias based on patient characteristics.Design
We examined data from 25,261 HIV-positive patients from the East Africa IeDEA Consortium.Methods
We used inverse probability of censoring weighting (IPCW) to represent patients not in care by patients in care with similar characteristics. We address two questions: What would the median CD4 be “had everyone starting ART remained on observation?” and “were everyone starting ART maintained on treatment?”Results
Routine CD4 count estimates were higher than adjusted estimates even under the best-case scenario of maintaining all patients on treatment. Two years after starting ART, differences between estimates diverged from 30 cells/µL, assuming similar mortality and treatment access among dropouts as patients in care, to over 100 cells/µL assuming 20% lower survival and 50% lower treatment access among dropouts. When considering only patients in care, the proportion of patients with CD4 above 350 cells/µL was 50% adjusted to below 30% when accounting for patients not in care. One-year mortality diverged 6–14% from the naïve estimates depending on assumptions about access to care among lost patients.Conclusions
Ignoring mortality and loss to care results in over-estimation of ART response for patients starting treatment and exaggerates the efficacy of treatment programs administering it. 相似文献70.
Objective: To determine the characteristics and risk factors of drug dependence among patients who were administered drugs with addictive potential (DAP) in an emergency department (ED).Methods: This retrospective cross-sectional study included patients who were administered DAP 3 or more times in the emergency room between September 1, 2019 and March 1, 2020. The demographic and baseline information were recorded. All the prescibed DAP, the reasons to use these drugs, secondary drug dependence, the department where DAP were first prescribed, types of doctors who preferred to prescribed DAP, and the risk factors for the development of drug dependence were determined. Results: A total of 3000 patients were screened from medical records, and among them, 80 patients developed drug dependence. Drug dependence only developed for tramadol (n=57, 71.3%), diazepam (n=11, 13.8%), and biperiden (n=12, 15.0%). Tramadol was the most frequently prescribed drug (n=57, 71.3%). The most common reason for drug dependence was psychiatric disorders (n=29, 36.3%). Drug dependence developed in renal colic patients due to the administration of tramadol (n=7, 100%). On the contrary, dependence to biperiden were mainly developed in patients with psychiatric complaints (n=12, 41.4%). The rate of secondary drug dependence was 15% (n=12). Of the Biperiden users, 41.7% developed secondary drug dependence on diazepam. Most DAP were first prescribed in the ED (n=52, 65%), and the specialist preferred to prescribe DAP (n=43, 53.8%). For the development of dependence, the presence of renal colic (OR: 3.387, 95% confidence interval (CI): 1.473-7.788, P=0.004) and low back pain (OR: 5.778, 95% CI: 2.779-12.014, P<0.001) were the risk factors. Conclusions: Most DAP were first prescribed in the ED compared to other departments, and specialist are preferred to use DAP. Tramadol is the most commonly used drugs caused drug dependence. Psychiatric disorder patients are easier to develope drug dependence. Furthermore, renal colic and low back pain patients needs more attention to avert drug dependence. 相似文献