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1.
The viability of the human probiotic strains Lactobacillus paracasei NFBC 338 and Bifidobacterium sp. strain UCC 35612 in reconstituted skim milk was assessed by confocal scanning laser microscopy using the LIVE/DEAD BacLight viability stain. The technique was rapid (<30 min) and clearly differentiated live from heat-killed bacteria. The microscopic enumeration of various proportions of viable to heat-killed bacteria was then compared with conventional plating on nutrient agar. Direct microscopic enumeration of bacteria indicated that plate counting led to an underestimation of bacterial numbers, which was most likely related to clumping. Similarly, LIVE/DEAD BacLight staining yielded bacterial counts that were higher than cell numbers obtained by plate counting (CFU) in milk and fermented milk. These results indicate the value of the microscopic approach for rapid viability testing of such probiotic products. In contrast, the numbers obtained by direct microscopic counting for Cheddar cheese and spray-dried probiotic milk powder were lower than those obtained by plate counting. These results highlight the limitations of LIVE/DEAD BacLight staining and the need to optimize the technique for different strain-product combinations. The minimum detection limit for in situ viability staining in conjunction with confocal scanning laser microscopy enumeration was ~108 bacteria/ml (equivalent to ~107 CFU/ml), based on Bifidobacterium sp. strain UCC 35612 counts in maximum-recovery diluent.  相似文献   

2.
The role of the food delivery matrix in probiotic performance in the intestine is not well understood. Because probiotics are often provided to consumers in dairy products, we investigated the contributions of milk to the health-benefiting performance of Lactobacillus casei BL23 in a dextran sulfate sodium (DSS)-induced murine model of ulcerative colitis. L. casei BL23 protected against the development of colitis when ingested in milk but not in a nutrient-free buffer simulating consumption as a nutritional supplement. Consumption of (acidified) milk alone also provided some protection against weight loss and intestinal inflammation but was not as effective as L. casei and milk in combination. In contrast, L. casei mutants deficient in DltD (lipoteichoic acid d-alanine transfer protein) or RecA (recombinase A) were unable to protect against DSS-induced colitis, even when consumed in the presence of milk. Mice fed either L. casei or milk contained reduced quantities of colonic proinflammatory cytokines, indicating that the L. casei DltD and RecA mutants as well as L. casei BL23 in nutrient-free buffer were effective at modulating immune responses. However, there was not a direct correlation between colitis and quantities of these cytokines at the time of sacrifice. Identification of the cecal microbiota by 16S rRNA gene sequencing showed that L. casei in milk enriched for Comamonadaceae and Bifidobacteriaceae; however, the consumption of neither L. casei nor milk resulted in the restoration of the microbiota to resemble that of healthy animals. These findings strongly indicate that probiotic strain efficacy can be influenced by the food/supplement delivery matrix.  相似文献   

3.
There has been much research on the effects of garlic (Allium sativum) on numerous pathogens, but very few, if any, studies on its effect on beneficial, probiotic bifidobacteria. We have recently shown that garlic exhibits antibacterial activity against bifidobacteria. The mechanism by which garlic kills bifidobacteria is yet to be elucidated. This study sought to determine the mechanism of action of garlic clove extract on selected Bifidobacterium species using scanning and transmission electron microscopy and SDS-PAGE analysis. SEM micrographs revealed unusual morphological changes such as cell elongation, cocci-shaped cells with cross-walls, and distorted cells with bulbous ends. With TEM, observed changes included among others, condensation of cytoplasmic material, disintegration of membranes, and loss of structural integrity. SDS-PAGE analysis did not reveal any differences in whole-cell protein profiles of untreated and garlic clove extract-treated cells. The current study is the first to reveal the mechanism of action of garlic clove extract on probiotic Bifidobacterium species. The results indicate that garlic affects these beneficial bacteria in a manner similar to that exhibited in pathogens. These results therefore further highlight that caution should be taken especially when using raw garlic and probiotic bifidobacteria simultaneously as viability of these bacteria could be reduced by allicin released upon crushing of garlic cloves, thereby limiting the health benefits that the consumer anticipate to gain from probiotics.  相似文献   

4.
Human body has developed a holistic defence system, which mission is either to recognize and destroy the aggressive invaders or to evolve mechanisms permitting to minimize or restore the consequences of harmful actions. The host immune system keeps the capital role to preserve the microbial intestinal balance via the barrier effect. Specifically, pathogenic invaders such as, bacteria, parasites, viruses and other xenobiotic invaders are rejected out of the body via barriers formed by the skin, mucosa and intestinal flora. In case physical barriers are breached, the immune system with its many components comes into action in order to fence infection. The intestine itself is considered as an “active organ” due to its abundant bacterial flora and to its large metabolic activity. The variation among different species or even among different strains within a species reflects the complexity of the genetic polymorphism which regulates the immune system functions. Additionally factors such as, gender, particular habits, smoking, alcohol consumption, diet, religion, age, gender, precedent infections and vaccinations must be involved. Hormonal profile and stress seems to be associated to the integrity microbiota and inducing immune system alterations. Which bacterial species are needed for inducing a proper barrier effect is not known, but it is generally accepted that this barrier function can be strongly supported by providing benefic alimentary supplements called functional foods. In this vein it is stressed the fact that early intestinal colonization with organisms such as Lactobacilli and Bifidobacteria and possibly subsequent protection from many different types of diseases. Moreover, this benefic microflora dominated but Bifidobacteria and Lactobacilli support the concept of their ability to modify the gut microbiota by reducing the risk of cancer following their capacity to decrease β-glucoronidase and carcinogen levels. Because of their beneficial roles in the human gastrointestinal tract, LAB are referred to as “probiotics”, and efforts are underway to employ them in modern nutrition habits with so-called functional foods. Members of Lactobacillus and Bifidobacterium genera are normal residents of the microbiota in the human gastrointestinal tract, in which they developed soon after birth. But, whether such probiotic strains derived from the human gut should be commercially employed in the so-called functional foods is a matter of debate between scientists and the industrial world. Within a few hours from birth the newborn develops its normal bacterial flora. Indeed human milk frequently contains low amounts of non-pathogenic bacteria like Streptococcus, Micrococcus, Lactobacillus, Staphylococcus, Corynebacterium and Bifidobacterium. In general, bacteria start to appear in feces within a few hours after birth. Colonization by Bifidobacterium occurs generally within 4 days of life. Claims have been made for positive effects of Bifidobacterium on infant growth and health. The effect of certain bacteria having a benefic action on the intestinal ecosystem is largely discussed during the last years by many authors. Bifidobacterium is reported to be a probiotic bacterium, exercising a beneficial effect on the intestinal flora. An antagonism has been reported between B. bifidum and C. perfringens in the intestine of newborns delivered by cesarian section. The aim of the probiotic approach is to repair the deficiencies in the gut flora and restore the protective effect. However, the possible ways in which the gut microbiota is being influenced by probiotics is yet unknown.  相似文献   

5.
In the present study, probiotic Dahi (LaBb Dahi) containing Lactobacillus acidophilus LaVK2 and Bifidobacterium bifidum BbVK3 was selected as a probiotic therapy to investigate its protective effect on dextran sodium sulfate (DSS)-induced ulcerative colitis model in mice that mimics the picture in human. LaBb Dahi was prepared by co-culturing Dahi bacteria (Lactococcus lactis ssp. cremoris NCDC-86 and Lactococcus lactis ssp. lactis biovar diacetylactis NCDC-60) along with selected strain of L. acidophilus LaVK2 and B. bifidum BbVK3 in buffalo milk (3% fat). Four groups of swiss albino male mice (12 each) were fed buffalo milk (3% fat), buffalo milk (3% fat) plus DSS, Dahi plus DSS, and LaBb Dahi plus DSS, respectively, for 17?days with basal diet. The myeloperoxidase (MPO) activity, levels of tumor necrosis factor-?? (TNF-??), interleukin-6 (IL-6) and interferon (IFN-??) were assessed as inflammatory markers, and the histopathological picture of the colon of mice was studied. DSS-induced colitis appeared to induce significant increase in MPO activity, levels of TNF-??, IL-6 and IFN-??. Feeding with LaBb Dahi offered significant reduction in MPO activity, levels of TNF-??, IL-6 and IFN-?? when compared to either buffalo milk group or group III (Dahi). The present study suggests that LaBb probiotic Dahi can be used to combat DSS-induced biochemical and histological changes and to achieve more effective treatment for ulcerative colitis.  相似文献   

6.
Bacteriocins are ribosomally-synthesized antibacterial peptides. These compounds are produced by a broad variety of different bacteria belonging mainly to the genus Bifidobacterium, to which health promoting properties have frequently been attributed. However, despite the fact that the identification of Bifidobacterium-associated bacteriocins was first reported in 1980 and that they exhibit antimicrobial activity against pathogenic microorganisms such as Listeria monocytogenes, Clostridium perfringens, and Escherichia coli, relatively little information is still available about the antimicrobial compounds produced by strains of this genus. More detailed understanding of the action mechanisms of these antimicrobials could allow us to determine the extent to which their production contributes to the probiotic properties of specific bifidobacteria strains and, potentially, be of crucial significance for ultimate preservation of functional foods or pharmaceutical applications. Here we review what is already known about their structure, classification, mode of action, functionality, immunity, production and purification.  相似文献   

7.
The probiotic adjunct Lactobacillus plantarum K25 was inoculated into milk to produce probiotic cheese. The effect of Lb. plantarum K25 on cheese composition, microbiological growth and survival during the manufacturing and ripening period, primary and secondary proteolysis during cheese ripening, and the in vivo cholesterol-lowering ability of the probiotic cheese were investigated. The results showed that the use of adjunct Lb. plantarum K25 in Cheddar cheese did not affect the cheese components including moisture, protein, fat, salt content and the pH value of cheese. During the whole ripening period, the probiotic adjunct maintained its viability, suggesting the effectiveness of Cheddar cheese as a vehicle for delivery of probiotic bacteria. No significant differences were observed in water-soluble nitrogen, 70?% ethanol-soluble nitrogen, 5?% phosphotungstic acid-soluble nitrogen, free amino acids and urea-PAGE patterns between the control and probiotic cheeses. Assessment of the in vivo cholesterol-lowering property of cheese with Lb. plantarum K25 showed that the levels of serum total cholesterol, low-density lipoprotein cholesterol and triglycerides decreased significantly, and the level of serum high-density lipoprotein cholesterol increased in mice fed with the probiotic cheese. The results indicated the potential function as a dietary item of the probiotic cheese with Lb. plantarum K25 to reduce the risk of cardiovascular diseases.  相似文献   

8.
Bacterial species of Bacillus, Lactobacillus, and Bifidobacterium in the intestinal tract have been used as probiotics. Selections for probiotic candidates by the culture-based approaches are time-consuming and labor-consuming. The aim of this study was to develop a new method based on sequencing strategies to select the probiotic Bacillus, Lactobacillus, and Bifidobacterium. The Illumina-based sequencing strategies with different specific primers for Bacillus, Clostridium, and Bifidobacterium were applied to analyze diversity of the genera in goat feces. The average number of different Bacillus, Clostridium, and Bifidobacterium OTUs (operational taxonomic units) at the 97% similarity level ranged from 1922 to 63172. The coverage index values of Bacillus, Clostridium, and Bifidobacterium calculated from the bacterial OTUs were 0.89, 0.99, and 1.00, respectively. The most genera of Bacillus (37.9%), Clostridium (53%), and Bifidobacterium (99%) were detected in goat feces by the Illumina-based sequencing with the specific primers of the genera, respectively. Higher phylogenetic resolutions of the genera in goat feces were successfully established. The results suggest that the selection for probiotic Bacillus, Clostridium, and Bifidobacterium based on the Illumina sequencing with their specific primers is reliable and feasible, and the core Bacillus, Clostridium, and Bifidobacterium species of healthy goats possess the potentials as probiotic microbial consortia.  相似文献   

9.
Fermentation is one of the oldest ways of processing food. Some fermented food is produced industrially, but can also be produced in an artisanal way by certain ethnic groups, called traditional fermented foods. In Mexico, there are a variety of traditional fermented beverages which are produced in an artisanal way. They include those made with maize (atole agrio, pozol, and tesgüino), fruit (tepache and colonche), and obtained by plant fermentation (pulque, tuba, and taberna). These beverages have been used since ancient times for religious and medicinal purposes. The medicinal effect may be due to fermented microorganisms. The presence of beneficial microorganisms known as probiotics provides beneficial effects to consumer health, improving the balance of intestinal host, and reducing the risk of gastrointestinal diseases, mainly. Most probiotics belong to the genus Lactobacillus, but Bifidobacterium, Bacillus, and yeast are also found. Therefore, it is important that the microbiological diversity of the beverages is studied and documented. This review includes information on the microbial diversity and probiotic potential of the most important traditional fermented beverages from Mexico.  相似文献   

10.
This study is aimed to isolate some novel probiotics from the soils of North East Himalayas. Eleven Gram positive isolates were obtained in MRS with Oxgall media from soil samples. Four of the isolates withstood the in vitro gastric juice pH 3.0 and 0.45% bile salt tolerance screening. Among these, PBT 3 showed high cell surface hydrophobicity and adhered to the Caco-2 cells. 16s rDNA gene sequences of this probiotic strains were identified as Bacillus amyloliquefaciens (accession no: JF836079). In in vivo bioefficacy evaluation by DSS-induced colitis animals, B. amyloliquefaciens significantly ameliorated the loss in body weight. Further, the treatment altered the levels of myeloperoxidase, lipoperoxides, and mucous content in the colon tissues compared with normal colon. It reduced the protein and mRNA levels of pro-inflammatory cytokines such as TNF-α and IL-1β. These biochemical findings were supported by histopathological evidences. Our study reports the use of B. amyloliquefaciens isolated from Himalayan soil as probiotic and its beneficial effect on IBD for the first time and suggests that this could be used as potential probiotics in functional foods or as a curative agent.  相似文献   

11.
Gulcin Alp  Belma Aslim 《Anaerobe》2010,16(2):101-105
The purpose of this study was to investigate a possible relation between resistance to bile salts and low pH with exopolysaccharide (EPS) producing of Bifidobacterium spp. In this study, a total of 31 Bifidobacterium spp. were isolated from breast fed infants feces and breast milk samples. As a result of the identification tests, isolates were identified as Bifidobacterium breve (15 strains), B. bifidum (11 strains), B. pseudocatenulatum (3 strains) and B. longum (2 strains). Bifidobacterium spp. were determined exopolysaccharide (EPS) production. EPS productions observed at chance rations (38.00–97.64 mg/l) among of Bifidobacterium spp. Furthermore, Bifidobacterium spp. were determined resistance to bile salts and low pH. Positive correlations between production of exopolysaccharide and resistance to bile salts (p < 0.01) or low pH (p < 0.01) were found Bifidobacterium spp. This investigation showed that high EPS production of Bifidobacteria may be important in the selection of probiotic strains for resistance to bile salts and low pH.  相似文献   

12.
Lactobacillus paracasei subsp. paracasei LC01 (LC01) can tolerate intestinal stresses and has antioxidant activity. To evaluate the effect of the bacterium on human intestinal microflora, a randomized, double-blind, placebo-controlled human trial was carried out. Fifty-two healthy adult volunteers were randomized equally to two groups. One group consumed 12% (wt/vol) skimmed milk supplemented with 1010 CFU of LC01 each day for the 4-week treatment period, and then consumed placebo in the next treatment period, separated by a 2-week washout. The other group followed the reverse order. Group-specific real-time PCR and biochemical analyses was used to determine the intestinal bacterial composition of fecal samples collected at the end of every period, and the concentration of short-chain fatty acids and ammonia. A significant inhibition in fecal Escherichia coli and increase in Lactobacillus, Bifidobacterium, and Roseburia intestinalis were observed after consumption of LC01. Acetic acid and butyric acid were significantly higher in the probiotic stage and fecal ammonia was significantly lower. The results indicated a modulation effect of LC01 on the intestinal microflora of young adults, suggesting a beneficial effect on bowel health. LC01 may have potential value as a probiotic.  相似文献   

13.
Lactic acid bacteria have long been used to improve the safety of foods through fermentation. Some fermented products were also early used for their perceived health benefits, which lead to the development of probiotics as we now know them. Probiotics mainly belong to the genera Lactobacillus and Bifidobacterium. Most members of these genera are not considered pathogens or even opportunistic pathogens. Nevertheless, rare cases of Lactobacillus and Bifidobacterium infection have been reported, possibly even associated with the consumption of probiotic products. Such cases are extremely rare and the subjects always had severe underlying conditions most often affecting the immune system. There does not seem to be any risk for the general population. Safety assessments can be performed and many possible tests exist. It is, however, not certain these tests will prevent rare case of Lactobacillus infection in certain high-risk patients. The benefits of probiotic use should be weighed against the possible small risk. Such an evaluation will, in most cases, be favourable and should therefore not discourage consumption of probiotics. Presented at the Second Probiotic Conference, Košice, 15–19 September 2004, Slovakia.  相似文献   

14.

According to FAO and WHO, probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Most probiotic bacteria used today belong to the genera Lactobacillus and Bifidobacterium and are of animal or human origin. The fundamental characteristic routinely evaluated in potential probiotics strains is their limited viability loss during gastrointestinal transit (GIT), but to date, no studies reported whether probiotics, besides viability, still also maintain their beneficial properties intact. To study this aspect, we considered two strains, Lactobacillus rhamnosus DTA 79 and L. paracasei DTA 83, previously characterised for the presence of some probiotic properties, isolated from faeces of 7- to 21-day-old babies. Here, we examined some additional properties, namely antibiotic resistance, resistance to lysozyme, presence of haemolytic activity and inhibition of pathogen biofilm formation. We then tested the effect of in vitro GIT on all these features and our results show evidence that this procedure had in some cases limited and in others no significant effects on them. Additionally, we examined the gastrointestinal resistance of the strains after skim milk fermentation and successive storage of the product for 20 and 40 days at refrigeration temperature, to see whether prolonged storage could weaken cell resistance to GIT. Our results demonstrate that a protracted refrigeration period before in vitro GIT did not affect or influenced very weakly this essential probiotic property.

  相似文献   

15.
Probiotics are live microorganisms that potentially confer beneficial outcomes to host by modulating gut microbiota in the intestine. The aim of this study was to comprehensively investigate effects of probiotics on human intestinal microbiota using 454 pyrosequencing of bacterial 16S ribosomal RNA genes with an improved quantitative accuracy for evaluation of the bacterial composition. We obtained 158 faecal samples from 18 healthy adult Japanese who were subjected to intervention with 6 commercially available probiotics containing either Bifidobacterium or Lactobacillus strains. We then analysed and compared bacterial composition of the faecal samples collected before, during, and after probiotic intervention by Operational taxonomic units (OTUs) and UniFrac distances. The results showed no significant changes in the overall structure of gut microbiota in the samples with and without probiotic administration regardless of groups and types of the probiotics used. We noticed that 32 OTUs (2.7% of all analysed OTUs) assigned to the indigenous species showed a significant increase or decrease of ≥10-fold or a quantity difference in >150 reads on probiotic administration. Such OTUs were found to be individual specific and tend to be unevenly distributed in the subjects. These data, thus, suggest robustness of the gut microbiota composition in healthy adults on probiotic administration.  相似文献   

16.
Summary: Since the discovery in 1899 of bifidobacteria as numerically dominant microbes in the feces of breast-fed infants, there have been numerous studies addressing their role in modulating gut microflora as well as their other potential health benefits. Because of this, they are frequently incorporated into foods as probiotic cultures. An understanding of their full interactions with intestinal microbes and the host is needed to scientifically validate any health benefits they may afford. Recently, the genome sequences of nine strains representing four species of Bifidobacterium became available. A comparative genome analysis of these genomes reveals a likely efficient capacity to adapt to their habitats, with B. longum subsp. infantis exhibiting more genomic potential to utilize human milk oligosaccharides, consistent with its habitat in the infant gut. Conversely, B. longum subsp. longum exhibits a higher genomic potential for utilization of plant-derived complex carbohydrates and polyols, consistent with its habitat in an adult gut. An intriguing observation is the loss of much of this genome potential when strains are adapted to pure culture environments, as highlighted by the genomes of B. animalis subsp. lactis strains, which exhibit the least potential for a gut habitat and are believed to have evolved from the B. animalis species during adaptation to dairy fermentation environments.  相似文献   

17.
Probiotics from an industrial perspective   总被引:1,自引:0,他引:1  
Probiotic products have gained popularity with consumers that expect that the products they consume are healthy and help them maintain health. Hence, the need and preferences of the consumers are translated into a product format concept. Probiotics have been used for a long time as natural components in supplements and functional foods, mainly in fermented dairy products. Most of the strains used as probiotics belong to the genera Lactobacillus and Bifidobacterium. By definition, a strain has to have documented health benefits, in order to be called a probiotic. Although each bacterial strain is unique, there are some points that are essential when selecting a probiotic regarding the genetic stability, survival, and technical properties of a strain. Proper components, food matrices and production processes need to be selected since the matrices may affect the viability of the strain in the product and the intestine. Survival in the product is considered a requirement for the beneficial effects of probiotics.  相似文献   

18.
Nowadays, the strong relationship between diet and health is well known. Although the primary role of diet is to provide nutrients to fulfill metabolic requirements, the use of foods to improve health and the state of well-being is an idea increasingly accepted by society in the last three decades. During the last years, an important number of scientific advances have been achieved in this field and, although in some situations, it is difficult to establish a distinction between “harmful” and “good” bacteria, experts agree in classifying the genera Bifidobacterium and Lactobacillus as beneficial bacteria. Thus, several strategies can be used to stimulate the proliferation of these beneficial intestinal bacteria, being one of them the consumption of prebiotics. The development of new prebiotics, with added functionality, is one of the most serious challenges shared not only by the scientific community but also by the food industry. The objective of this work was to evaluate the potential prebiotic effect of red and white grape residues, both obtained during the winemaking process. For such purpose, an in vitro study with pure cultures of Lactobacillus and Bifidobacterium was first conducted. Secondly, a study with mixed cultures using human fecal inocula was carried out in a simulator of the distal part of the colon. The obtained results showed an increase in the Lactobacillus and Bifidobacterium population, indicating that these ingredients are serious candidates to be considered as prebiotics.  相似文献   

19.
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis (JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with 16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target for using probiotics in the management of IgE-mediated allergic disorders including JCPsis.  相似文献   

20.
The nutritional status of pregnant women is vital for healthy outcomes and is a concern for a large proportion of the world''s population. The role of the microbiota in pregnancy and nutrition is a promising new area of study with potential health ramifications. In many African countries, maternal and infant death and morbidity are associated with malnutrition. Here, we assess the influence of probiotic yogurt containing Lactobacillus rhamnosus GR-1, supplemented with Moringa plant as a source of micronutrients, on the health and oral, gut, vaginal, and milk microbiotas of 56 pregnant women in Tanzania. In an open-label study design, 26 subjects received yogurt daily, and 30 were untreated during the last two trimesters and for 1 month after birth. Samples were analyzed using 16S rRNA gene sequencing, and dietary recalls were recorded. Women initially categorized as nourished or undernourished consumed similar calories and macronutrients, which may explain why there was no difference in the microbiota at any body site. Consumption of yogurt increased the relative abundance of Bifidobacterium and decreased Enterobacteriaceae in the newborn feces but had no effect on the mother''s microbiota at any body site. The microbiota of the oral cavity and GI tract remained stable over pregnancy, but the vaginal microbiota showed a significant increase in diversity leading up to and after birth. In summary, daily micronutrient-supplemented probiotic yogurt provides a safe, affordable food for pregnant women in rural Tanzania, and the resultant improvement in the gut microbial profile of infants is worthy of further study.  相似文献   

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