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881.
882.
Sequences intervening between the core packaging determinants are dispensable for maintaining the packaging potential and propagation of feline immunodeficiency virus transfer vector RNAs 总被引:2,自引:0,他引:2 下载免费PDF全文
Mustafa F Ghazawi A Jayanth P Phillip PS Ali J Rizvi TA 《Journal of virology》2005,79(21):13817-13821
883.
Necatt?n?TürkmenEmail author Mustafa?Aslan Atabay?Düzenli 《Biodiversity and Conservation》2005,14(10):2291-2297
The natural flora of Karkamis Dam lake area and its surroundings was studied in 2000 and 2001 before the dam construction
was completed. During the floristic surveys, 464 species of 279 genera belonging to 70 families were recorded. The number
of endemic species is 14. The phytogeographic elements are represented in the study as follows; Irano-Turanian 104 (18.2%),
Mediterranean 66 (11.5%), Euro-Siberian 7 (1.2%), Cosmopolitan 9 (1.5%), Sharo-Arabian 1 (0.1%). The phytogeographic region
of 383 taxa (67.1%) is unknown, or multiregional. The spectrum of the basic life forms is as follows; Therophytes 50.0%, Hemicryptophytes
33.4%, Phanerophytes 5.2%, Geophytes 5.2%, Chamaephytes 4.3% and Hydrophytes 1.9%. According to the IUCN Red List Categories,
28 threatened plant species were identified in the study area. 相似文献
884.
885.
Comprehensive studies of the human skeletal features and variations between and within populations are beneficial both for clinical applications and determination of racial characteristics of populations. The aim of this study was to examine the location and anthropometric characteristics of the mental foramen in 36 adult male mandibles of the Late Byzantine period. The results demonstrated that the most common position of the mental foramen was in line with the longitudinal axis of the second premolar (50% right side; 47% left side) followed by a location between the first and second premolars (33% right side; 36% left side). When compared with the results of previous similar studies, the results obtained in the present study suggest that traits such as the localization of mental foramen may not only differ between populations of different geographic environment but also within the inhabitants of the same geography. 相似文献
886.
Bagasra O Patel D Bobroski L Abbasi JA Bagasra AU Baidouri H Harris T El-Roeiy A Lengvarszky Z Farzadegan H Wood C 《Journal of molecular histology》2005,36(6-7):401-412
SummaryObjectives: Defining the mechanism of infection with human herpesvirus-8 (HHV-8) or Kaposi’s sarcoma associated herpesvirus (KSHV) is an important clinical issue. HHV-8 has been linked to Kaposi’s sarcoma (KS) development in HIV-1-infected individuals, and KS develops in 40% of those infected with both viruses. A series of epidemiological data suggest that sexual transmission is one of the routes of transmission for HHV-8. In our studies, we sought to assess the cellular reservoirs of HHV-8 DNA in the semen of HIV-1-infected men and the potential role of HHV-8 infected spermatozoa in horizontal transmission.Design and methods: A nested polymerase chain reaction (PCR), in situ PCR (ISPCR) and a sodium iodide (NaI) DNA isolation technique that extracts both nuclear and episomal DNA were utilized to amplify specific genes in vitro and within intact cells to evaluate the types of seminal cells infected with HHV-8 in HIV-1-infected and uninfected men.Results HHV-8 was present in the spermatozoa and mononuclear cells of the semen in 64 of 73 (88%) HIV-1 infected individuals. Both the sperms as well as the mononuclear cells of the semen specimens of HIV-1 infected men were found to be infected with HHV-8. Multiplex ISPCR revealed that a significantly higher percentage of semen cells were infected with HHV-8 than HIV-1 (p>0.001). Rare (less than one in a 100,000) sperm cells were co-infected with both viruses. A co-culture of HHV-8 infected sperm with uninfected 293 or Sup-T1 cell lines resulted in an abortive infection of these cells with HHV-8. DNA isolation by NaI yielded 73% of the positive sperm, whereas the standard phenol/chloroform method resulted in significantly lower positives (45%) from the same specimens.Conclusions: Design and methods: Our data strongly suggest a potential sexual/horizontal route of transmission of HHV-8, via the HHV-8 infected sperm and other semen cells, where a large percentage of HIV-1 infected men’s sperm and other semen cells are infected with HHV-8. Co-culture studies have further supported the observations that HHV-8 in the sperm cells is infectious and capable of transmission of the virus to uninfected cells. 相似文献
887.
888.
Comparison of closely related,uncultivated Coxiella tick endosymbiont population genomes reveals clues about the mechanisms of symbiosis 下载免费PDF全文
Despina Tsementzi Juan Castro Gordillo Mustafa Mahagna Yuval Gottlieb Konstantinos T. Konstantinidis 《Environmental microbiology》2018,20(5):1751-1764
Understanding the symbiotic interaction between Coxiella‐like endosymbionts (CLE) and their tick hosts is challenging due to lack of isolates and difficulties in tick functional assays. Here we sequenced the metagenome of a CLE population from wild Rhipicephalus sanguineus ticks (CRs) and compared it to the previously published genome of its close relative, CLE of R. turanicus (CRt). The tick hosts are closely related sympatric species, and their two endosymbiont genomes are highly similar with only minor differences in gene content. Both genomes encode numerous pseudogenes, consistent with an ongoing genome reduction process. In silico flux balance metabolic analysis (FBA) revealed the excess production of L‐proline for both genomes, indicating a possible proline transport from Coxiella to the tick. Additionally, both CR genomes encode multiple copies of the proline/betaine transporter, proP gene. Modelling additional Coxiellaceae members including other tick CLE, did not identify proline as an excreted metabolite. Although both CRs and CRt genomes encode intact B vitamin synthesis pathway genes, which are presumed to underlay the mechanism of CLE‐tick symbiosis, the FBA analysis indicated no changes for their products. Therefore, this study provides new testable hypotheses for the symbiosis mechanism and a better understanding of CLE genome evolution and diversity. 相似文献
889.
890.