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排序方式: 共有9831条查询结果,搜索用时 15 毫秒
31.
Concepcin Martínez Lucia del Rio Agustín Portela Esteban Domingo Juan Ortín 《Virology》1983,130(2):539-545
The complete genetic information for the neuraminidase (NA) gene of influenza virus A/Bangkok/1/79 has been cloned by in vitro synthesis of dsDNA, insertion into pBR322 plasmid, and transformation of Escherichia coli. The nucleotide sequence of the NA gene has been determined by the Maxam and Gilbert method. It is 1466 nucleotides long and contains a single open reading frame with a coding capacity for 469 amino acids. When compared to the NA genes of the N2 strains A/Victoria/3/75, A/Udorn/72, A/NT/60/68, and A/RI/5-/57, 90% of the nucleotide positions and 87% of the amino acid positions remained invariant. Forty-two nucleotide changes and 14 amino acid changes accumulated in the period 1975-1979, but the general structure of the protein appeared to remain constant. 相似文献
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33.
Role of the virology laboratory in diagnosis and management of patients with central nervous system disease. 总被引:4,自引:1,他引:4 下载免费PDF全文
A number of viruses cause acute central nervous system disease. The two major clinical presentations are aseptic meningitis and the less common meningoencephalitis. Clinical virology laboratories are now more widely available than a decade ago; they can be operated on a modest scale and can be tailored to the needs of the patients they serve. Most laboratories can provide diagnostic information on diseases caused by enteroviruses, herpesviruses, and human immunodeficiency virus. Antiviral therapy for herpes simplex virus is now available. By providing a rapid diagnostic test or isolation of the virus or both, the virology laboratory plays a direct role in guiding antiviral therapy for patients with herpes simplex encephalitis. Although there is no specific drug available for enteroviruses, attention needs to be paid to these viruses since they are the most common cause of nonbacterial meningitis and the most common pathogens causing hospitalization for suspected sepsis in young infants in the United States during the warm months of the year. When the virology laboratory maximizes the speed of viral detection or isolation, it can make a significant impact on management of these patients. Early viral diagnosis benefits patients with enteroviral meningitis, most of whom are hospitalized and treated for bacterial sepsis or meningitis or both; these patients have the advantage of early withdrawal of antibiotics and intravenous therapy, early hospital discharge, and avoidance of the risks and costs of unnecessary tests and treatment. Enteroviral infection in young infants also is a risk factor for possible long-term sequelae. For compromised patients, the diagnostic information helps in selecting specific immunoglobulin therapy. Good communication between the physician and the laboratory will result in the most benefit to patients with central nervous system viral infection. 相似文献
34.
9q34 loss of heterozygosity in a tuberous sclerosis astrocytoma suggests a growth suppressor-like activity also for the TSC1 gene 总被引:5,自引:2,他引:5
Carbonara Caterina; Longa Lucia; Grosso Enrico; Borrone Carla; Garre Maria Grazia; Brisigotti Massimo; Migone Nicola 《Human molecular genetics》1994,3(10):1829-1832
Tuberous sclerosis is an autosomal dominant disease whose characteristicfeature is the development of multiple hamartomas in a varietyof organs and tissues. Two major loci have been identified sofar: TSC1 on chromosome 9q34 and TSC2 on chromosome 16p13.3.Loss of heterozygosity at 16p13.3-associated markers has beenrecently observed in hamartomatous lesions of some tuberoussclerosis patients. Here we report the first evidence of lossof heterozygosity at the TSC1 critical region in a giant cellastrocytoma of a familial tuberous sclerosis case. Segregationanalysis showed that the 9q34 haplotype lost carried the putativenormal TSC1 gene. These data support the hypothesis of botha germline and somatic loss-of-function mutation for the developmentof tuberous sclerosis hamartomas and suggest a tumor-suppressor-likeactivity also for the TSC1 gene product. Finally, the possiblesignificance of a second small region of loss of heterozygosityat 9p21, found in the same astrocytoma, is discussed. 相似文献
35.
Heterogeneous pattern of chromosomal breakpoints involving the MYC locus in multiple myeloma 总被引:2,自引:0,他引:2
Fabris S Storlazzi CT Baldini L Nobili L Lombardi L Maiolo AT Rocchi M Neri A 《Genes, chromosomes & cancer》2003,37(3):261-269
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM. 相似文献
36.
37.
Jernimo P. Martins Lucia C. Silva Matheus S. Nunes Gabriel Rübensam Jarbas R. Oliveira Rodrigo B. M. Silva Maria M. Campos 《Nutrients》2021,13(4)
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice. 相似文献
38.
Zuzana Paduchov Barbora Katren
íkov Magdalna Vavkov Lucia Laubertov Zuzana Nagyov Iveta Garaiova Zdenka ura
kov Jana Trebatick 《Nutrients》2021,13(4)
In the DEPOXIN project, we have found that a high ratio of omega-6/omega-3 fatty acids (FA) is associated with worsening of depressive symptoms in children and adolescents with depressive disorder (DD) and that the 12-week omega-3 FA supplementation modulates DD symptoms. Here we present our results of the secondary outcomes: the levels of thromboxane (TXB), brain-derived neurotrophic factor (BDNF), homocysteine (HCy) and vitamin D. Fifty-eight patients were randomized into two arms. One group received a fish oil emulsion enriched with omega-3 FA, and the other received a sunflower oil emulsion containing omega-6 FA, for 12 weeks. Depressive symptoms were evaluated, using the Child’s Depressive Inventory (CDI). The patients with DD had elevated TXB levels and decreased vitamin D levels, as compared to healthy controls. Both CDI and omega-6/omega-3 ratio correlated positively with TXB and negatively with BDNF at baseline. Compared to the omega-6 FA group, the supplementation with omega-3 FA for 12 weeks significantly reduced plasma TXB (p = 0.024) and increased BDNF (p = 0.011) levels. No changes in HCy and vitamin D were observed. Our results demonstrate the possible role of TXB and BDNF in the pathophysiology of DD and the benefits of omega-3 FA supplementation. The study was registered with the ISRCTN registry (ISRCTN81655012). 相似文献
39.
Dan Liu Maria Lucia Pace Maria Goddard Rowena Jacobs Raphael Wittenberg Anne Mason 《Health economics》2021,30(1):36-54
Since 2010, adult social care spending in England has fallen significantly in real terms whilst demand has risen. Reductions in social care supply may also have impacted demand for NHS services, particularly for those whose care is provided at the interface of the health and care systems. We analyzed a panel dataset of 150 local authorities (councils) to test potential impacts on hospital utilization by people aged 65 and over: emergency admission rates for falls and hip fractures (“front‐door” measures); and extended stays of 7 days or longer; and 21 days or longer (“back‐door” measures). Changes in social care supply were assessed in two ways: gross current expenditure (per capita 65 and over) adjusted by local labor costs and social care workforce (per capita 18 and over). We ran negative binomial models, controlling for deprivation, ethnicity, age, unpaid care, council class, and year effects. To account for potential endogeneity, we ran instrumental variable regressions and dynamic panel models. Sensitivity analysis explored potential effects of funding for integrated care (the Better Care Fund). There was no consistent evidence that councils with higher per capita spend or higher social care staffing rates had lower hospital admission rates or shorter hospital stays. 相似文献
40.