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1.
The results of the field trials of the vaccine "Act-Hib" against Haemophilus influenzae of type b, presented for registration by Pasteur Mérieux Connaught (France), are summarized. The vaccine was found to have low reactogenicity and high immunological effectiveness. A single injection of the vaccine induced the formation of the protective level of anti-PRP antibodies in 94% of the immunized children aged 1-4 years. After immunization the mean geometric titers of specific antibodies increased sixfold in comparison with the initial level and were equal to 3.4 mu/ml. On the basis of the data of laboratory control and field clinical trials the vaccine "Act-Hib" was registered in the Russian Federation and permission and its practical use in the public health service of the country was permitted.  相似文献   

2.
On April 17-18th 2013,the 4th meeting of the Mérieux Chinese Research Network was held in Wuhan,an event organized by Institut Mérieux,together with the Wuhan Institute of Virology,Chinese Academy of Sciences,Huangzhong University of Science and Technology,and the Chinese Society for Microbiology.  相似文献   

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4.
The BioMerieux NucliSENS easyMAG total nucleic acid extractor was evaluated for use on bacterial isolates in the clinical microbiology laboratory. Forty eight isolates were extracted, yielding quantifiable amounts of DNA for all isolates. The easyMAG is appropriate for DNA extraction from bacterial isolates and will be incorporated in the clinical laboratory.  相似文献   

5.
A current view of the emergence of pandemic influenza viruses envisages a gene flow from the aquatic avian reservoir to humans via reassortment in pigs, the hypothetical "mixing vessel." Understanding arising from recent H5N1 influenza outbreaks in Hong Kong since 1997 and the isolation of avian H9N2 virus from humans raises alternative options for the emergence of a new pandemic virus. Here we report that H9N2 influenza viruses established in terrestrial poultry in southern China are transmitted back to domestic ducks, in which the viruses generate multiple reassortants. These novel H9N2 viruses are double or even triple reassortants that have amino acid signatures in their hemagglutinin, indicating their potential to directly infect humans. Some of them contain gene segments that are closely related to those of A/Hong Kong/156/97 (H5N1/97, H5N1) or A/Quail/Hong Kong/G1/97 (G1-like, H9N2). More importantly, some of their internal genes are closely related to those of novel H5N1 viruses isolated during the outbreak in Hong Kong in 2001. This study reveals a two-way transmission of influenza virus between terrestrial and aquatic birds that facilitates the generation of novel reassortant H9N2 influenza viruses. Such reassortants may directly or indirectly play a role in the emergence of the next pandemic virus.  相似文献   

6.

Background

Except during a 1-year period when BCG vaccine was not routinely administered, annual coverage of infants with Bacillus Calmette-Guérin (BCG) in Kazakhstan since 2002 has exceeded 95%. BCG preparations from different sources (Japan, Serbia, and Russia) or none were used exclusively in comparable 7-month time-frames, September through March, in 4 successive years beginning in 2002. Our objective was to assess relative effectiveness of BCG immunization.

Methods/Findings

We compared outcomes of birth cohorts from the 4 time-frames retrospectively. Three cohorts received vaccine from one of three manufacturers exclusively, and one cohort was not vaccinated. Cohorts were followed for 3 years for notifications of clinical TB and of culture-confirmed TB, and for 21 months for TB meningitis notifications. Prevention effectiveness based on relative risk of TB incidence was calculated for each vaccinated cohort compared to the non-vaccinated cohort.Although there were differences in prevention effectiveness observed among the three BCG vaccines, all were protective. The Japanese vaccine (currently used in Kazakhstan), the Serbian vaccine, and the Russian vaccine respectively were 69%, 43%, and 22% effective with respect to clinical TB notifications, and 92%, 82%, and 51% effective with respect to culture confirmed TB. All three vaccines were >70% effective with respect to TB meningitis.

Limitations

Potential limitations included considerations that 1) the methodology used was retrospective, 2) multiple risk factors could have varied between cohorts and affected prevention effectiveness measures, 3) most cases were clinically diagnosed, and TB culture-positive case numbers and TB meningitis case numbers were sparse, and 4) small variations in reported population TB burden could have affected relative risk of exposure for cohorts.

Conclusions/Significance

All three BCG vaccines evaluated were protective against TB, and prevention effectiveness varied by manufacturer. When setting national immunization policy, consideration should be given to prevention effectiveness of BCG preparations.  相似文献   

7.
de Avila GN  de Avila GA  Gauer GJ 《Bioethics》2003,17(5-6):425-431
In the 1960s, when Dr. Belding Scribner discovered how to accomplish the process of dialysis in a repeated way, he could not imagine that in solving such a problem others as or more difficult would appear. Given the technological progress and the impossibility of assisting all patients through the most modern methods, the medical doctor often finds himself faced with the moral dilemma of choosing which patient in the waiting list will receive the treatment. This same dilemma is amplified in the case of organ transplants. Professionals, students, professors of the juridical and health fields, and the population in general, were interviewed as a means of documenting the moral concepts and opinions surrounding this problem. In the reality in which we find ourselves, it seems to us that deciding who lives, and the responsibility for all the events that culminate in such decisions, is still a subject left open to discussion.  相似文献   

8.
We studied the taxonomy and biogeography of Mazama bricenii, a brocket deer classified as Vulnerable by the IUCN, drawing on qualitative and quantitative morphology and sequences of the mitochondrial cytochrome-b gene. We used Ecological Niche Modeling (ENM) to evaluate the hypothesis that M. bricenii of the Venezuelan Cordillera de Mérida (CM) might have become isolated from populations of its putative sister species, Mazama rufina, in the Colombian Cordillera Oriental (CO). This hypothesis assumes that warm, dry climatic conditions in the Táchira Depression were unsuitable for the species. Our analyses did not reveal morphological differences between specimens geographically attributable to M. bricenii and M. rufina, and phylogenetic analyses of molecular data recovered M. bricenii nested within the diversity of M. rufina. These results indicate that M. bricenii should be regarded as a junior synonym of M. rufina. ENM analyses revealed the existence of suitable climatic conditions for M. rufina in the Táchira Depression during the last glacial maximum and even at present, suggesting that gene flow between populations in the CO and CM may have occurred until at least the beginning of the current interglacial period and may continue today. Because this pattern might characterize other mammals currently considered endemic to the CM, we examined which of these species match two criteria that we propose herein to estimate if they can be regarded as endemic to the CM with confidence: (1) that morphological or molecular evidence exists indicating that the putative endemic taxon is distinctive from congeneric populations in the CO; and (2) that the putative endemic taxon is restricted to either cloud forest or páramo, or both. Only Aepeomys reigi, Cryptotis meridensis, and Nasuella meridensis matched both criteria; hence, additional research is necessary to assess the true taxonomic status and distribution of the remaining species thought to be CM endemics.  相似文献   

9.
10.
Wild-caught flies of Drosophila melanogaster from seven natural populations of extreme regions of Brazil (São Luís, MA; Teresina, PI; Rio Cipó, MG; Maringá, PR; São José do Rio Preto, SP; Joinville, SC; and Porto Alegre, RS) were studied with the purpose of evaluating hybrid dysgenesis due to mobilization of P elements and the regulatory capacity of the strains' cytotypes. Diagnostic crosses were made and the strains classified according to their P–M phenotypes. Four strains were classified as moderate P (MA, MG, PI, and SP), two as Q (PR and RS) and one as M′ (SC). Females of southern strains (PR, SC, and RS) presented in A crosses lower degrees of gonadal dysgenesis scores than those from northern strains (MA and PI).  相似文献   

11.
Distribution-free statistical tests offer clear advantages in situations where the exact unadjusted -values are required as input for multiple testing procedures. Such situations prevail when testing for differential expression of genes in microarray studies. The Cramér-von Mises two-sample test, based on a certain -distance between two empirical distribution functions, is a distribution-free test that has proven itself as a good choice. A numerical algorithm is available for computing quantiles of the sampling distribution of the Cramér-von Mises test statistic in finite samples. However, the computation is very time- and space-consuming. An counterpart of the Cramér-von Mises test represents an appealing alternative. In this work, we present an efficient algorithm for computing exact quantiles of the -distance test statistic. The performance and power of the -distance test are compared with those of the Cramér-von Mises and two other classical tests, using both simulated data and a large set of microarray data on childhood leukemia. The -distance test appears to be nearly as powerful as its counterpart. The lower computational intensity of the -distance test allows computation of exact quantiles of the null distribution for larger sample sizes than is possible for the Cramér-von Mises test.[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25]  相似文献   

12.
The damaging effects of light that was emitted by a DRSh250-3 mercury lamp on the DNA of mouse blood leukocytes was studied in vitro. It was shown that the main DNA damage is due to the action of UVB radiation (280–320 nm). Under the combined effects of the UV radiation and the orange–red fluorescent component it was found that the additional fluorescent light with the spectral maximum at 625 nm from nanoluminophore materials (quantum dots that are based on CdSe/ZnS, CdSe/CdS/ZnS) protected the cellular DNA from the damaging effect of UV radiation. Using nanomolar concentrations of hydrogen peroxide, the hypothesis of the role of reactive oxygen species in the protective effects of the red–orange light was tested in vitro. It was shown for the first time that the mechanisms of the protective effects are associated with the induction of an adaptive response by nanomolar concentrations of hydrogen peroxide that are induced by the orange–red light.  相似文献   

13.
14.
Forest fires have environmental, social and economic impacts in many areas. Various factors related to territory directly influence both the number and the surface area of each fire. The link between different variables (climate, social and environmental) in the risk of fire and in the characteristics of fires is studied here through Partial Least Squares - Path Models. In addition, images from the Sentinel-2 sensor and geographic information systems are used to create a cartographic base of fires in the Transboundary Biosphere Reserve of Galicia and the Site of Community Importance of Xurés (Galicia) between 2015 and 2020. In all, seven variables are analyzed in this study area using the partial least squares-path modeling method: climate, topography, land use, type of environmental protection, the anthropogenic factor, fire defense, and fire data (severity and area). The parameters for each variable are used to obtain weights and thus determine the importance of each one. The areas where the problem of forest fires is greatest are those with the greatest environmental protection. Up to 31% of the surface area of the Natura 2000 Network was burned in the 6-year study period. Topography and land use are also shown to be relevant factors in the effects of forest fires in this territory. By contrast, higher population density and the development of infrastructures such as roads and water tanks mitigate the impact of fires. The problem of forest fires encompasses many variables that need to be studied. By contextualizing each study area as far as possible, specific measures to prevent and reduce damage can be drawn up.  相似文献   

15.
Through histological analyses, this study reveals an unusually high incidence of hermaphroditism in Chiton articulatus. Specimens were sampled every 30?days between September 2010 and September 2011 at two locations (Las Brisas and Jaramillo beaches, Acapulco) on the tropical eastern Pacific coast of Mexico. At both sites, hermaphroditism was found throughout the year, although in varying proportions. Higher percentages of hermaphroditism were found during the pre-spawning summer months (Las Brisas Beach 63%, Jaramillo Beach 68%). Two different kinds of hermaphroditic gonads were found, showing a preponderance of either male or female tissues but, commonly, female tissues occupied the greatest part of the gonad cross sections. Similar to other species of polyplacophorans, there was a predominance of males, although M:F sex ratios ranged from 0.7 to 4.5: 1 at Las Brisas Beach and 0.3–8: 1 at Jaramillo Beach.  相似文献   

16.
Bacillus and Pseudomonas are the dominant groups of bacteria known for their antagonistic potential against many plant and animal pathogens. Presently, exploration of these genera with antagonistic property for disease management of aquaculture system is gaining more importance to overcome the use of antibiotics and related resistance issues. Rapid screening and identification of these genera from diverse bacterial populations by conventional methods is laborious, cost-intensive, and time-consuming. To overcome these limiting factors, in the present study, a colony multiplex PCR (cmPCR) method was developed and evaluated for the rapid detection of Bacillus and Pseudomonas. The technique amplifies the partial 16S rRNA gene of Bacillus and Pseudomonas with a product size of ~1,100 and ~375 bp, respectively, using single forward (BSF2) and two reverse primers (PAGSR and BK1R). Reliability of the cmPCR method was confirmed by screening 472 isolates obtained from ten different eco-stations, of which 133 isolates belonged to Bacillus and 32 to Pseudomonas. The cmPCR method also helped to identify six different Pseudomonas spp. and 14 different Bacillus spp. from environmental samples. Of the total 472 isolates studied, 46 showed antagonistic activity, among which 63 % were Bacillus and 17.4 % were Pseudomonas. Thus, the newly developed molecular approach provides a quick, sensitive, and potential screening tool to detect novel, antagonistically important Bacillus and Pseudomonas genera for their use in aquaculture. Further, it can also act as a taxonomic tool to understand the distribution of these genera from wide ecological niches and their exploitation for diverse biotechnological applications.  相似文献   

17.
This study explores the management of inland fisheries on common lands (ejidos) within the Mayan Zone of Quintana Roo, Mexico. Qualitative survey data are used to examine whether there are (a) ongoing fishery conservation activities; (b) local caretakers of fishing sites; (c) restrictions on where fishing can take place; and (d) particular groups of individuals who lack the right to fish within the ejidos. Results indicate that in contrast to other local resources, fisheries in the ejidos have less defined use rights, being viewed as largely “open access”. In particular, most feel that outsiders can fish in an ejido if they abide by local rules (notably not damaging the local water bodies, asking consent to fish, and having a friend or relative in the community). However, there are within-community differences in views concerning management and conservation, with those more dependent on fishing being more likely to support exclusion of outsiders.  相似文献   

18.
Two new species of diphyllidean cestodes, Echinobothrium mexicanum n. sp., and Echinobothrium fautleyae n. sp., are described, the former from the spiral intestines of the bat rays Myliobatis californicus and Myliobatis longirostris and the latter from the spiral intestine of the cownose ray Rhinoptera steindachneri, all caught in the Gulf of California, México. Echinobothrium mexicanum is most easily distinguished from the majority of the species of the genus by the number of large apical hooks in each dorsoventral group (23) and from the remainder in the number of lateral hooklets in each group on the scolex. Echinobothrium fautleyae differs conspicuously from all other members of the genus in that the first and last lateral hooklets in each group are distinctly larger than the other hooklets in each group. Serial sections of the scoleces of these 2 new species confirm that the attachment structures on the scolex are bothria, rather than bothridia, as has been described in other species in the genus, suggesting that the attachment structures of the scolex should be examined in more detail in the genus in general. Palmate microtriches of various forms cover the proximal bothrial surfaces of both new species and are also found on the dorsal bothrial surfaces of E. fautleyae. The distal bothrial surfaces of E. mexicanum are covered with slender spiniform and short filiform microtriches. The cephalic peduncles of both species possess short filiform microtriches only. Comparison of these 2 new species with the other 3 species in this genus that have been examined with SEM suggests that the various forms and distributions of these microtriches is unique in each of these 2 species. We believe these features will prove to be taxonomically useful.  相似文献   

19.
Mobile genetic elements are responsible for most spontaneous mutations in Drosophila melanogaster. The discovered in the 1980s phenomenon of frequent change of the wild-type yellow phenotype for a mutant one, and vice-versa, in strains of D. melanogaster isolated from the Uman' natural population can be, according to our data, explained by repeated inversions and reinversions of the gene regulatory region located between the two copies of the hobo transposon. However, most molecular genetic events accompanying the process can occur without the phenotype change. After several generations, the strains, remaining phenotypically unchanged, can possess different molecular genetic properties with respect to yellow. Using genetically homogenous or isogenic strains for the genetic analysis or for production of the new plant cultivars or animal breeds, geneticists and breeders often face the problem of stability of the strains. In the present study, the mechanism underlying the generation of instability at the yellowlocus of D. melanogaster determined by the hobo-induced genome instability is described.  相似文献   

20.
Mutations at codons 526 and 531 in the rpoB gene and at 315 in the katG gene are considered diagnostic markers for resistance to rifampin and isoniazid in tuberculosis. The aim of this study was to design and evaluate three TaqMan probes for the identification of these mutations in 138 respiratory samples positive for acid-fast bacilli, and 32 clinical isolates from a region with considerable levels of drug resistance. The specificities of the probes for the diagnosis of resistance to both drugs were 100%; however, the sensitivities were calculated to be 50% for isoniazid and 56% for rifampin. DNA sequencing of rpoB and katG; and the spoligotyping assay of the clinical isolates, confirmed the diversity of the mutations and the presence of 11 spoligotypes with a shared international type and eight unique spoligotypes. Analysis of the respiratory samples identified 22 (16%) as drug-resistant and 4 (3%) as multidrug-resistant tuberculosis. The diagnostic value of the TaqMan probes was compromised by the diversity of mutations found in the clinical isolates. This highlights the need for better understanding of the molecular mechanisms responsible for drug resistance prior to the use of molecular probes, especially in regions with significant levels of drug-resistant tuberculosis.  相似文献   

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