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91.
92.

Background

During the 2009 influenza pandemic, individuals over the age of 60 had the lowest incidence of infection with approximately 25% of these people having pre-existing, cross-reactive antibodies to novel 2009 H1N1 influenza isolates. It was proposed that older people had pre-existing antibodies induced by previous 1918-like virus infection(s) that cross-reacted to novel H1N1 strains.

Methodology/Principal Findings

Using antisera collected from a cohort of individuals collected before the second wave of novel H1N1 infections, only a minority of individuals with 1918 influenza specific antibodies also demonstrated hemagglutination-inhibition activity against the novel H1N1 influenza. In this study, we examined human antisera collected from individuals that ranged between the ages of 1 month and 90 years to determine the profile of seropositive influenza immunity to viruses representing H1N1 antigenic eras over the past 100 years. Even though HAI titers to novel 2009 H1N1 and the 1918 H1N1 influenza viruses were positively associated, the association was far from perfect, particularly for the older and younger age groups.

Conclusions/Significance

Therefore, there may be a complex set of immune responses that are retained in people infected with seasonal H1N1 that can contribute to the reduced rates of H1N1 influenza infection in older populations.  相似文献   
93.
ABSTRACT: BACKGROUND: Traditional medicine (TM) occupies a special place in the management of diseases in Uganda. Not with standing the many people relying on TM, indigenous knowledge (IK) related to TM is getting steadily eroded. To slow down this loss it is necessary to document and conserve as much of the knowledge as possible. This study was conducted to document the IK relevant to traditional medicine in the districts of Mukono, Nakapiripirit, Kanungu and Pallisa, in Uganda. METHODS: An ethnobotanical survey was conducted between October 2008 and February 2009 using techniques of key informant interviews and household interviews. RESULTS: The common diseases and conditions in the four districts include malaria, cough, headache, diarrhea, abdominal pain, flu, backache and eye diseases. Respondents stated that when they fall sick they self medicate using plant medicines or consult western-trained medicine practitioners. Self medication using herbal medicines was reported mostly by respondents of Nakapiripirit and Mukono. Respondents have knowledge to treat 78 ailments using herbal medicines. 44 species, mentioned by three or more respondents have been prioritized. The most frequently used part in herbal medicines is the leaf, followed by the stem and root. People sometime use animal parts, soil, salt and water from a grass roof, in traditional medicines. Herbal medicines are stored for short periods of time in bottles. The knowledge to treat ailments is acquired from parents and grandparents. Respondents' age and tribe appears to have a significant influence on knowledge of herbal medicine, while gender does not. CONCLUSION: This survey has indicated that IK associated with TM stills exists and that TM is still important in Uganda because many people use it as a first line of health care when they fall sick. Age and tribe influence the level of IK associated with herbal medicine, but gender does not.  相似文献   
94.
ABSTRACT: Laparoscopic colectomy is now widely applied to cases of malignancy, supported by early data from several large randomized controlled trials. Long-term follow-up is now available from those trials, supporting equivalency of cancer-free and overall survival for open and laparoscopic resections. This promising data has inspired further exploration of other applications of laparoscopic techniques, including use of single incision laparoscopy. This article reviews recent reports of long-term data for colorectal cancer resection from four randomized, prospective international trials.  相似文献   
95.
ABSTRACT: BACKGROUND: Clostridium difficile is the main cause of antibiotic associated diarrhea. In the past decade, the number of C. difficile patients has increased dramatically, coinciding with the emergence of two PCR ribotypes, 027 and 078. PCR ribotype 078 is also frequently found during C. difficile outbreaks in pigfarms. Previously, the genome of the PCR ribotype 078 strain M120, a human isolate, was described to contain a unique insert of 100 kilobases. RESULTS: Analysis of this insert revealed over 90 open reading frames, encoding proteins originating from transposons, phages and plasmids. The insert was shown to be a transposon (Tn6164), as evidenced by the presence of an excised and circularised molecule, containing the ligated 5'and 3'ends of the insert. Transfer of the element could not be shown through filter-mating experiments. Whole genome sequencing of PCR ribotype 078 strain 31618, isolated from a diarrheic piglet, showed that Tn6164 was not present in this strain. To test the prevalence of Tn6164, a collection of 231 Clostridium difficile PCR ribotype 078 isolates from human (n = 173) and porcine (n = 58) origin was tested for the presence of this element by PCR. The transposon was present in 9 human, tetracycline resistant isolates, originating from various countries in Europe, and none of the pig strains. Nine other strains, also tetracycline resistant human isolates, contained half of the transposon, suggesting multiple insertion steps yielding the full Tn6164. Other PCR ribotypes (n = 66) were all negative for the presence of the transposon. Multi locus variable tandem repeat analysis revealed genetic relatedness among transposon containing isolates. Although the element contained several potential antibiotic resistance genes, it did not yield a readily distinguishable phenotype. CONCLUSIONS: Tn6164 is a newly described transposon, occurring sporadically in C. difficile PCR ribotype 078 strains. Although no transfer of the element could be shown, we hypothesize that the element could serve as a reservoir of antibiotic resistance genes for other bacteria. Further research is needed to investigate the transfer capabilities of the element and to substantiate the possible role of Tn6164 as a source of antibiotic resistance genes for other gut pathogens.  相似文献   
96.
97.
GenBank.   总被引:4,自引:1,他引:3       下载免费PDF全文
The GenBank sequence database incorporates DNA sequences from all available public sources, primarily through the direct submission of sequence data from authors and from large-scale sequencing projects. Data exchange with the EMBL Data Library and the DNA Data Bank of Japan helps ensure comprehensive coverage. GenBank continues to focus on quality control and annotation while expanding data coverage and retrieval services. An integrated retrieval system, known asEntrez, incorporates data from the major DNA and protein sequence databases, along with genome maps and protein structure information. MEDLINE abstracts from published articles describing the sequences are also included as an additional source of biological annotation. Sequence similarity searching is offered through the BLAST family of programs. All of NCBI's services are offered through the World Wide Web. In addition, there are specialized server/client versions as well as FTP and e-mail server access.  相似文献   
98.
Oligodeoxyribonucleotides cross-linked by reductively activated mitomycin C (MC) were prepared and purified for the first time. The cross-linked products were structurally characterized by nucleoside and MC-nucleoside adduct analysis. Optimal conditions were established for the cross-linking reaction, resulting in high yields, typically in the 20-50% range. Nuclease digests of the cross-linked oligonucleotides yielded the same bifunctional MC-deoxyguanosine adduct as that previously isolated from DNA exposed to MC in vitro and in vivo [Tomasz et al. (1987) Science 235, 1204]. The cross-linked oligonucleotides displayed broad thermal melting profiles, greatly increased Tm, and complex circular dichroism spectra. Phosphodiester linkages at the cross-link were resistant to spleen exonuclease, nuclease P1, and TaqI and ClaI restriction endonucleases; snake venom diesterase action was uninhibited. The cross-links are stable to heat at neutral pH but are removed by treatment in hot piperidine or by the reducing agents Na2S2O4 and dithiothreitol. Mechanisms are proposed for these reactions. These studies define optimal methods for introducing mitomycin cross-links into DNA fragments at a specific site, providing a versatile tool to study the effects of the MC cross-links on DNA structure and function.  相似文献   
99.
100.
The effects of concentrations of volatile fatty acids on an anaerobic, glucose-limited, and pH-controlled growing culture of Salmonella enterica serovar Enteritidis were studied. Suddenly increasing volatile fatty acids to the concentrations representative of the ceca of 15-day-old broiler chickens caused washout of serovar Enteritidis. In contrast, a sudden increase to the volatile fatty acid concentrations representative of the ceca of younger broiler chickens caused a reduction in the biomass but not washout. Gradually increasing volatile fatty acids caused a gradual decrease in the biomass of serovar Enteritidis. We conclude that the concentrations of volatile fatty acids present in the ceca of broilers with a mature microflora can cause washout of serovar Enteritidis in an in vitro system mimicking cecal ecophysiology.  相似文献   
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