Evolution of the digestive microflora in a unit of specified-pathogen-free mice: efficiency of the barrier.

RhoIco strain], barrier-maintained since 1970, is described. Some "contaminants" appeared spontaneously during the period 1971-1973, but microorganisms belonging to the genera Lactobacillus Streptococcus, Enterobacteria, Escherichia and Bacillus remained stable. The methods of investigation used were not suitable for the assessment of strictly anaerobic strains. The stability of the digestive microflora durine the last 2 years of this study is believed to be related to the skill and conscientiousness of the technicians responsible for the daily care of these mice.     

澜沧江两条支流捕食线虫真菌水陆分布差异及关联性

为探究微生物在流域中的水、陆分布差异和相互关系,对澜沧江两条支流捕食线虫真菌多样性水陆分布进行了调查研究。在枯水期,以澜沧江一级支流沘江和黑惠江为研究区域,系统布设12个采样点(水流交汇点),每个采样点采集水、陆对称样品各5份,共采集土样120份。结合传统分离纯化、形态学及分子生物学方法筛选和鉴定菌株,按照《Nematode-Trapping Fungi》进行分类,共获得2属13种88株捕食线虫真菌;其中,陆地样品中共分离到2属11种45株,水体底泥中分离出1属10种43株,检出率分别为41.67%和53.33%。结果表明,澜沧江两条支流捕食线虫真菌在物种、属、群落结构3个层面上均存在水陆差异,也相互联系;陆地土壤可能是流域内捕食线虫真菌多样性的源,水流是其重要的传播因子。在流域生态系统内,水陆间的扩散限制和水流的连通性都是维持微生物物种多样性的重要机制。     

宏基因组测序分析东寨港红树林淤泥和水体微生物的多样性

为深入了解海南东寨港红树林生态系统微生物多样性及其在氮、磷、硫等代谢循环中的功能特点,本研究采用宏基因组测序,从物种注释与丰度、群落功能及多样性指数等角度,分析红树林淤泥和水体生境中微生物群落结构及生态功能的特异性。结果显示,在淤泥中检测到53个门、909个属的微生物类群,有3个占比超过1%的优势门类,其中变形杆菌门为83.78%,处于绝对优势,其下的12个优势属全部来自变形杆菌门;不动杆菌属是聚磷微生物的主要类群,其在淤泥中含量是水体的107.7倍,硫氧化单胞菌属、脱硫杆菌属是硫化物代谢的主要菌属,主要存在于淤泥生境当中。在水体中检测到64个门、1 522个属,包括13个优势门类、7个优势属;Nitrospinae和硝化螺旋菌门是亚硝酸盐氧化代谢的关键类群,两者在水体中占比分别是淤泥中的28.1倍和6.8倍。多样性评估得知,水体样品中的Shannon Wiener指数和Simpson指数均高于淤泥样品,两样品在属分类学单元上的Simpson指数趋近于1,表明红树林生态系统具有非常高的微生物多样性,水体生境的微生物多样性高于淤泥;亚硝酸盐的微生物代谢循环主要发生在水体生境中,微生物对磷的富集作用和硫化合物的氧化还原代谢主要发生在淤泥生境中。本研究有助于认识东寨港红树林湿地生境中的微生物资源状况,为保护红树林生态系统和开发利用其中的微生物资源提供依据。     

New approaches for isolation of previously uncultivated oral bacteria

A significant number of microorganisms from the human oral cavity remain uncultivated. This is a major impediment to the study of human health since some of the uncultivated species may be involved in a variety of systemic diseases. We used a range of innovations previously developed to cultivate microorganisms from the human oral cavity, focusing on anaerobic species. These innovations include (i) in vivo cultivation to specifically enrich for species actively growing in the oral cavity (the "minitrap" method), (ii) single-cell long-term cultivation to minimize the effect of fast-growing microorganisms, and (iii) modifications of conventional enrichment techniques, using media that did not contain sugar, including glucose. To enable cultivation of obligate anaerobes, we maintained strict anaerobic conditions in most of our cultivation experiments. We report that, on a per cell basis, the most successful recovery was achieved using minitrap enrichment (11%), followed by single-cell cultivation (3%) and conventional plating (1%). Taxonomically, the richest collection was obtained using the single-cell cultivation method, followed by minitrap and conventional enrichment, comprising representatives of 13, 9, and 4 genera, respectively. Interestingly, no single species was isolated by all three methods, indicating method complementarity. An important result is the isolation and maintenance in pure culture of 10 strains previously only known by their molecular signatures, as well as representatives of what are likely to be three new microbial genera. We conclude that the ensemble of new methods we introduced will likely help close the gap between cultivated and uncultivated species from the human oral cavity.     

青藏高原垫状点地梅叶际及内生可培养微生物多样性

【背景】垫状点地梅作为青藏高原最具代表性的垫状植物,其叶际和内生微生物对适应极端环境有重要意义,同时也是一种独特的资源。【目的】探究垫状点地梅叶际和叶内可培养微生物多样性,以及不同生存状态个体之间的微生物差异。【方法】采用纯培养方法分离和纯化3个不同地区垫状点地梅叶际和叶内的细菌、酵母菌和丝状真菌,并用16S rRNA基因和ITS区域序列进行分析鉴定。【结果】最终得到叶际微生物350株,鉴定为22属49种,优势种为Penicillium sajarovii;内生微生物274株,鉴定为19属45种,优势种为Bacillusmycoides;两者的优势属均为Penicillium。垫状点地梅叶际和叶内之间及不同生存状态个体之间微生物的α多样性大多无显著差异,各群落间的成员也有重叠,但物种组成存在显著的空间异质性。【结论】垫状点地梅叶际和叶内有着丰富的可培养微生物资源,来源于不同生存状态的个体或不同部位的微生物物种组成差别较大,微生物对不同环境的选择偏好形成了不同的群落模式。但这些不同来源的微生物群落之间同样存在高比例的共有菌株,这些共有菌株的异养方式和生态位并不固定,可兼共生和腐生生存,生...     

Analysis of Corynebacterium vaginale by an Immunodiffusion Technique

An immunodiffusion technique was employed to study the antigenic relationship of Corynebacterium vaginale isolates, vaginal diphtheroids, and members of the genera Corynebacterium and Lactobacillus. Antisera were prepared against C. vaginale ATCC strain 14018 grown diphasically and on blood agar plates and were tested against extracts of organisms prepared by sonication. Ouchterlony analysis demonstrated that all of the isolates of C. vaginale examined possess a common antigenic determinant. No antigenic relationship was detected between C. vaginale and members of the genera Corynebacterium or Lactobacillus. This study also demonstrated that alterations in the cultural conditions can cause variations in the antigenic composition of C. vaginale.     

Investigation of microbial diversity of underground waters in monitoring deep horizons of the Earth’s crust

In the present study, the gas-chromatography—mass-spectrometry methods and classic bacteriology were used for investigation of microbiological diversity of underground waters in the Vorotilov deep well (East European platform, at 1500, 1900, 3200, 3800, and 4500 m). Mineralization of underground waters was high, 160–190 g/l. The data on microbial diversity (21–27 species of bacteria depending on fluid permeability) and total number of microorganisms (1–1000 g/ml) were obtained by gas-chromatography-mass-spectrometry analysis of specific biomarkers of microbial cells and by classical bacteriological cultivation on selectve media. Dominant groups among native microorganisms were the genera Clostridium, Corynebacterium, and Rhodococcus. Prevalence of heterotriophic processes was noted. The number of chemolithoautotrophic microorganisms was insignificant, but they increase when there is lower pollution of water. The number of chemolithoautotrophs was low. However, they increased when water pollution was lower (which was shown by classic bacteriology methods). The “detritus” type of the investigated subsurface ecosystem might result from contamination of underground water by a drilling solution. Biomarker monitoring along the column of a deep well reflected the hydrodynamics determined both by geological conditions and exploitation of the well.     

Using 18S rDNA to resolve diaptomid copepod (Copepoda: Calanoida: Diaptomidae) phylogeny: an example with the North American genera

The phylogenetic relationships among the numerous genera of diaptomid copepods remain elusive due to difficulties in obtaining sufficient numbers of phylogenetically informative morphological characters for cladistic analysis. Molecular phylogenetic techniques offer high potential to resolve phylogenetic relationships in the absence of sufficient morphological characters because of the ease in which many characters can be unambiguously coded. I present the first molecular phylogeny for diaptomid copepod genera using 18S rDNA. Specifically, I test Light’s (1939) hypothesis regarding the interrelationships among the North American diaptomid genera. The 18S phylogeny is remarkably consistent with Light’s hypothesis. The endemic North American genera represent a monophyletic group exclusive of the non-endemic genera. Moreover, his hypothesized basal genus for the North America genera, Hesperodiaptomus, is the basal genus in this analysis. However, his Leptodiaptomus group is not reciprocally monophyletic with his Hesperodiaptomus group, but is rather a derived member of the latter group. Finally, the genus Mastigodiaptomus is found to be more closely allied with the non-endemic genera, as Light suggested. This phylogeny contributes heavily to the understanding of phylogenetic relationships among North American diaptomids and has large implications for the systematics of diaptomids in general. The use of 18S rDNA sequences in phylogenetic analyses of diaptomid copepods can be used to confirm the monophyly of recognized genera, the interrelationships among genera, and subsequent biogeographic interpretation of the family’s diversification. The use of molecular data, such as 18S rDNA sequences, to test phylogenetic hypotheses based on a very limited number of morphological characters will be a particularly useful approach to phylogenetic analysis in this system.     

DNA binding and antigenic specifications of DNA gyrase.

Complexes of DNA gyrase and minichromosomal DNA containing the origin of replication of Escherichia coli (oriC) can be formed without metabolic energy and visualised by electron microscopy. The A subunit, part of the A2B2-DNA gyrase complex is the binding protein. Various binding sites are scattered around the minichromosomal DNA including oriC. The minimal origin contains the only prominent and reproducible binding site. Binding to this site is suppressed by oxolinic acid and the ATP analogue beta-y-imido ATP. If gyrase isolated from the gram-positive bacterium Bacillus subtilis is used no binding to oriC is seen. This observation is consistent with antigenic differences between the A subunits of the two microorganisms. The binding to oriC might reflect a requirement for DNA gyrase during the initiation of DNA replication.     

A broad spectrum monoclonal antibody to alpha-tubulin does not recognize all protozoan tubulins

Summary Monoclonal antibodies able to recognize single antigenic determinants are a powerful tool for the study of immunological heterogeneity of antigens. In this paper we have used a monoclonal antibody against the -subunit of pig brain tubulin (TU-01) to investigate the immunoreactivity of tubulins from mammals, avians, amphibia, echinodermata, plathelmints, slime moulds and protozoa. Immunoreactivity was detected using immunoblotting and indirect immunofluorescence of isolated cells. Our results show that the antigenic determinant recognized by the TU-01 antibody is present in all metazoan tubulin tested and among the eukaryotic microorganisms only in the flagellateTrichomonas vaginalis. Indirect immunofluorescence also reveals that not allTrichomonas microtubules are stained by TU-01 antibody indicating the presence of different tubulins within a single cell. This results are consistent with the multitubulin hypothesis (Fulton andSimpson 1976).     

Monitoring of microbial degraders in manned space stations

Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium, Aspergillus, Cladosporium, and Aureobasidium; 3 yeast species belonging to the genera Debaryomyces, Candida, and Rhodotorula; and 4 bacterial species belonging to the genera Bacillus, Myxococcus, and Rhodococcus. The predominant species in all samples was Penicillium chrisogenum. It was shown that the fungi isolated could damage polymers and induce corrosion of aluminum-magnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.     

A comparative analysis of phloem exudate proteins from Cucumis melo,Cucumis sativus and Cucurbita maxima by polyacrylamide gel electrophoresis and isoelectric focusing

Summary Proteins in sieve tube exudate from Cucumis melo L., Cucumis sativus L. and Cucurbita maxima Duch. were analysed by gel electrophoresis and isoelectric focusing. Estimated molecular weights and isoelectric points for the major and minor proteins from each plant species are presented. Electrophoresis revealed striking differences between the protein complements of exudatc from the two genera investigated. Similarly, although a few exudate proteins from the two species of Cucumis possessed identical molecular weights, several major proteins were peculiar to each species. Isoelectric focusing of proteins in exudate samples from the three plants confirmed the marked differences in their protein complements. Furthermore, focusing also revealed differences between cultivars of Cucumis sativus. Both Cucumis sativus and Cucurbita maxima possessed relatively large amounts of basic proteins; these were absent in exudate from Cucumis melo. The implications of these results are discussed in relation to present concepts regarding the interrelationships and possible functional roles of P-proteins.Abbreviations DTT dithiothreitol - Bis N,N-methylenebisacrylamide - SDS Sodium dodecyl sulphate - TCA trichloroacetic acid     

Quantifying Antigenic Relationships among the Lyssaviruses

All lyssaviruses cause fatal encephalitis in mammals. There is sufficient antigenic variation within the genus to cause variable vaccine efficacy, but this variation is difficult to characterize quantitatively: sequence analysis cannot yet provide detailed antigenic information, and antigenic neutralization data have been refractory to high-resolution robust interpretation. Here, we address these issues by using state-of-the-art antigenic analyses to generate a high-resolution antigenic map of a global panel of 25 lyssaviruses. We compared the calculated antigenic distances with viral glycoprotein ectodomain sequence data. Although 67% of antigenic variation was predictable from the glycoprotein amino acid sequence, there are in some cases substantial differences between genetic and antigenic distances, thus highlighting the risk of inferring antigenic relationships solely from sequence data at this time. These differences included epidemiologically important antigenic differences between vaccine strains and wild-type rabies viruses. Further, we quantitatively assessed the antigenic relationships measured by using rabbit, mouse, and human sera, validating the use of nonhuman experimental animals as a model for determining antigenic variation in humans. The use of passive immune globulin is a crucial component of rabies postexposure prophylaxis, and here we also show that it is possible to predict the reactivity of immune globulin against divergent lyssaviruses.Rabies remains a globally important zoonosis, despite being one of the oldest recognized infectious diseases (27, 55). The majority of rabies in terrestrial animals and humans is caused by classical rabies virus (RABV), a lyssavirus in the family Rhabdoviridae. Since the 1950s, many related lyssaviruses which are capable of causing clinical rabies have been identified. The majority of those viruses have been isolated from bats (Chiroptera), including four divergent viruses, which were isolated in separate geographic locations throughout Eurasia in the past 18 years (2, 29, 31). The Chiroptera, therefore, represent a global reservoir for lyssaviruses, creating the potential for “spillover” infection to terrestrial mammals, including humans. Occasionally transmission between members of a new host species will occur, with potential for a subsequent adaptation in that species (35). Phylogenetic evidence suggests that one or more host-switching events from bats into terrestrial mammals were originally responsible for the ongoing global epidemic of terrestrial RABV (6).Pre- or postexposure prophylaxis, using vaccination and passive immune globulin administration according to World Health Organization (WHO) guidelines, is currently the only effective way to prevent rabies after infection with a lyssavirus (1). The efficacy of both active and passive immunization is likely to be affected by antigenic differences between viruses. The lyssavirus trimeric glycoprotein is the primary surface antigen, the major target for neutralizing antibodies (8), and is involved in cell binding and entry (34, 36, 53). Antigenic sites on the glycoprotein have been described using monoclonal antibody escape mutants (8, 16, 47, 51). These studies have elucidated two major sites (sites II and III) and multiple minor sites. Although estimates of antigenic differences can be made using information regarding these known antigenic sites, protein structure, and amino acid properties, predictions of the relative importance of those sites and specific mutations within those sites cannot be quantitatively tested without a method to reliably measure antigenic effect.The use of serological cross neutralization data to measure antigenic difference is limited by the reliability of the serological test and, more importantly, by paradoxes, or irregularities in the data. These irregularities include higher heterologous than homologous titers and individual variations between sera raised against the same antigen (22, 52). Hence, serological data are considered to have low resolution, and they are often used only qualitatively. Despite these difficulties, studies have attempted to further quantify antigenic differences among lyssaviruses. Badrane et al. (5) showed a linear correlation between the glycoprotein amino acid identity and four cross neutralization titers. Other studies have demonstrated variable serological cross-reactivity between European bat lyssaviruses (EBLV) and RABVs (10, 11) and suggested that antigenic relationships between EBLV-1 and EBLV-2 may not be fully reflected in the genetic relationships (41). Recent investigations into the efficacy of biologics against the Eurasian lyssaviruses showed an array of relatedness between lyssavirus species, with, for example, a murine anti-Aravan virus (anti-ARAV) serum neutralizing Khujand virus (KHUV) and ARAV equally but an anti-KHUV serum being less effective at neutralizing ARAV than KHUV (22). Until recently, however, there were no established tools for the quantitative analysis of antigenic data.Here we resolve the issue of quantitative interpretation of antigenic data using antigenic cartography. Antigenic cartography is a theory and associated computational method that resolves the paradoxes in the interpretation of antigenic data and makes possible high-resolution quantitative analyses and visualizations of binding assay data (15, 20, 25, 44, 49, 52).Integrating antigenic data with direct sequencing data, here we quantify the antigenic and genetic variation among a global panel of lyssaviruses, including representatives from all lyssavirus species. Furthermore, we address two key issues in the development of antilyssavirus biologics: the appropriateness of animal models and the development of efficacious alternatives to human rabies immune globulins (HRIGs).     

Intragranular processing of pro-opiomelanocortin in the intermediate cells of the rat pituitary glands

Summary Quantitative immunocytochemical studies were done by using the immunogold technique on sections of the intermediate lobe of rat pituitary. Antibodies raised (in rabbits) against the precursor proteins pro-opiomelanocortin (POMC) and ACTH were used. The results clearly indicate that the immature granules are the major site of POMC, as their antigenic density (gold beads/m²) was almost 3 times as high as that of ACTH. In the mature igranules, the antigenic density of ACTH was increased by 2.7-fold compared with the immature granules. Using a computer-assisted method, it was possible to categorize the granules antigenic density according to their size. Using this approach it was found that the antigenic density of POMC remained constant in all mature granules of varied sizes, whereas the antigenic density of ACTH decreased with increasing granule size. The relationship between granule size, degree of maturation, and antigenic density is discussed.     

Phospholipide Turnover in Microsomal Membranes of the Pancreas during Enzyme Secretion

After incubation of pigeon pancreas slices with P³² and isolation of various fractions by differential centrifugation the deoxycholate extract of the microsome fraction was found to account for over half of the phospholipide P and over half of the P³² incorporated into the phospholipides. The remaining phospholipide P and P³² were fairly evenly distributed in the nuclei, zymogen granules, mitochondria, microsomal ribonucleoprotein particles, and the soluble fraction. When enzyme secretion was stimulated with acetylcholine about two-thirds of the increment in radioactivity in the total phospholipides was found in deoxycholate soluble components of the microsome fraction. The remainder of the increment was distributed in the other fractions. This indicates that the cellular component in which the increase in phospholipide turnover occurs on stimulation of secretion is a membranous structure. Evidence is presented which indicates that the increment in radioactivity in the non-microsomal fractions on stimulation of secretion is due to contamination of these fractions with fragments of the stimulated membranous structure. The distribution of P³² radioactivity in each of the chromatographically separated phospholipides in the various fractions from unstimulated tissue paralleled the distribution of radioactivity in the total phospholipide fraction, indicating that individual phospholipides are not concentrated in different fractions but are associated together in the membranous structures of the microsome fraction. The major proportion of the stimulation of the turnover of the individual phospholipides also occurred in the microsome fraction. The distribution of radioactivity from glycerol-1-C¹⁴ in the total phospholipides and in the individual phospholipides in the various fractions was similar to the distribution of P³². In the microsome fraction acetylcholine stimulated the incorporation of glycerol-1-C¹⁴ in each phospholipide which showed a stimulation of P³² incorporation. The significance of the turnover of phosphatides in microsomal membranes in relation to the mechanism of secretion is discussed.     

Phylogenetic relationships of fossil and Recent gonorynchiform fishes (Teleostei: Ostariophysi)

This paper represents the first cladistic analysis of the interrelationships of all nominal fossil and living gonorynchiform genera. Gonorynchiformes is the basal group of the superorder Ostariophysi, and is confirmed as monophyletic on the basis of 12 synapomorphies. The Gonorynchiformes is be subdivided into two monophyletic suborders, Chanoidei and Gonorynchoidei. The Chanoidei includes the family Chanidae, which in turn includes the Recent Chanos plus five fossil genera, grouped in two subfamilies: Chaninae (( Chanos +† Tharrhiai) + † Parachanos +† Dastilbe ) and † Rubiesichthyinae († Rubiesichthys +† Gordichthys ). † Aethalionopsis is the sister-group to the Chanidae. Gonorynchoidei includes two families Gonorynchidae and Kneriidae. Gonorynchidae is formed by ( Gonorynchus, † Notogoneus ) and four fossil taxa of uncertain definition and interrelationships: †Charitosomus, † Charitopsis, † Ramallichthys, and †fudeichthys. The last four genera were previously included in the families †Charitosomidae and †Judeichthyidae, which could not be supported as monophyletic in this analysis. Kneriidae consists of two subfamilies Phractolaeminae with one genus Phractolaemus, and Kneriinae which includes (( Kneria + Parakneria ) + ( Grasseichthys + Cromeria )), the latter two being paedomorphic forms. The Phractolaeminae and the Kneriinae are freshwater African taxa with no known fossil record. The order Gonorynchiformes is represented herein by 18 genera, extending back to the Early Cretaceous. More work is required to clarify the interrelationships of the Gonorynchidae and the paedomorphic characters that apparently played an important role in the evolution of this morphologically diverse group of fishes.     

Molecular resolution of the systematics of a problematic group of fishes (Teleostei: Osmeridae) and evidence for morphological homoplasy

Relationships among the species of Northern Hemisphere smelts (family Osmeridae) have long been debated in the fish systematics literature. Eight independent studies based on morphological characters failed to reach any consensus on osmerid interrelationships. We reconstruct the osmerid phylogeny based on DNA sequence data from three mitochondrial (cytb, 16S, 12S) and three nuclear (ITS2, S71, RAG1) gene regions from multiple individuals of the 14 species in 6 genera, using the Japanese ayu (Plecoglossus altivelis) as the outgroup. Analyses with different combinations of nuclear and mitochondrial datasets yielded a generally well-resolved phylogeny of the genera that conflicts with previous hypotheses of osmerid interrelationships, and Shimodaira–Hasegawa tests suggest our topology with the current molecular dataset is significantly better than earlier reconstructions. In addition, mapping 114 morphological characters used in previous studies onto our phylogeny shows widespread homoplasy, which is likely the source of the systematic disagreement produced in earlier works.     

Antibiotic sensitivity and other properties of bacteria of the genus Aeromonas

Antibiotic sensitivity and other biological properties of Aeromonas and NAD-vibrios isolated from water of open waterbodies were studied comparatively. It was found that the organisms of these genera had a definite similarity with respect to antibiotic sensitivity, morphological, cultural and some antigenic properties. The differences in the antibiotic sensitivity of these organisms were not sufficient for definition of the taxonomic features.     

Schistosoma mansoni: detection and characterization of antigens and antigenemia by inhibition enzyme-linked immunosorbent assay (IELISA)

An inhibition enzyme-linked immunosorbent assay (IELISA) was used to detect the presence of schistosome antigens obtained from cercariae, adult worms, and eggs of the parasite. Using appropriate titers of Schistosoma mansoni infected mouse serum (IMS), it was possible to detect less than 10 ng/ml of schistosome antigen when added to phosphate-buffered saline (PBS, pH 7.2) or normal human serum (NHS). The sensitivity of the test was highly contingent on the number of experimental variables including antibody titer and antigenic source. The results of specificity studies were complicated. Although there was no cross-reactivity detected with other unrelated antigen preparations, extensive cross-reactivity between various schistosome species and "stage-specific" antigens was observed. The IELISA, utilizing IMS, can quantitate the degree of antigenic cross-reactivity, i.e., genus-specific and cross-reacting antigenic determinants. Soluble egg antigen (SEA) preparations obtained from S. mansoni and S. japonicum actually "cross-reacted" more than cercarial- and egg-derived antigens obtained from the same species (S. mansoni). This test also showed a 32-fold increase in specificity for the quantitative detection of specific antigenic determinants when monoclonal antibodies were used to restrict the heterogeneity of the measured response. The technique proved satisfactory for the quantification of parasitic burden in mice and the detection of active infections in humans. Circulating antigen disappeared with a t 1/2 of 72-96 hr after successful treatment.     

常见变质水性工业产品中的微生物种类和耐药性分析

为了科学治理常见变质水性工业产品中的腐败微生物,对其进行分离、鉴定和分类,同时以卡松、布罗波尔、甲基异噻唑啉酮和苯并异噻唑啉酮四种杀菌防腐剂对6种标准细菌菌株的最小抑菌浓度(MIC)作为耐药性标准,对腐败细菌进行耐药性评估分析.结果显示,日化用品变质样中革兰氏阴性细菌约占80.00％(克雷伯氏菌属、假单胞菌属、伯克霍尔...