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1.
The correlation of plasmid profiles with infectivity was investigated by using five clones of Borrelia burgdorferi sensu stricto strain B31 (ATCC 35210). Plasmid profiles were determined by pulsed-field and two-dimensional gel electrophoresis. The 50% infectious dose (ID50) in hamsters was determined. The ID50 of the clone that possessed a full complement of eight linear and three circular plasmids was 10(3) cells. The loss of the 27.5- and 40-kb linear plasmids did not decrease the infectivity of these cells. Rather, the loss of the 27.5-kb linear plasmid was associated with a more disseminated infection. A moderate decrease of the ID50 from 10(3) to 10(5) cells correlated with the loss of the 9.0-kb circular plasmid and the 27.5-kb linear plasmid. A major loss of infectivity (ID50 > 10(3) cells) occurred with cells that lost the 24.7- and 27.5-kb linear plasmids and the 9.0-kb circular plasmid. A 3.0-kb HindIII fragment of the 24.7-kb linear plasmid was used as a probe to determine the presence of the homologous sequences in the three genospecies of Lyme disease spirochetes. An analysis of 21 infectious strains of B. burgdorferi sensu stricto, B. garinii, and B. afzelii revealed a consistent association of infectivity with strains possessing a linear plasmid (size range, 24 to 36 kb) that hybridized with the HindIII fragment. Western immunoblotting with hamster antisera against infectious B31 clone C-3 revealed two proteins with molecular masses of 28 and 43 kDa that were absent in the noninfectious B31 clone C-1. Additionally, a 14-kDa protein was absent in C-1 but present in infectious clone C-9 as shown by two-dimensional polyacrylamide gel electrophoresis.  相似文献   

2.
The performance of Western blots (immunoblots) prepared with eight strains of Borrelia burgdorferi representing B. burgdorferi sensu stricto, B. garinii, and B. afzelii genospecies was tested with a panel of sera with various clinical presentations collected from eight geographic regions. European sera were generally more reactive to blots prepared with B. garinii or B. afzelii strain antigens, in particular B. garinii 20047 and B. afzelii VS461. North American sera were more reactive with B. burgdorferi sensu stricto strains. Our observation of significant differences in the levels of reactivity of some sera on Western blots of certain strains is potentially important for the development and implementation of generic interpretive criteria. Preferential reactivity of sera from patients with nerve and/or palsy symptoms to B. garinii strains and with cutaneous disease to B. afzelii strains was observed. On the basis of our results, we have concluded that strain 20047 is the best strain to use for the development of a generic Lyme borreliosis Western blot for Europe.  相似文献   

3.
Involvement of the nervous system in Lyme borreliosis may occur with or without erythema migrans and it may present with a variety of neurological symptoms. In this study we analysed phenotypic and genotypic characteristics of 40 Borrelia strains isolated from cerebrospinal fluid (CSF) of 38 Slovenian patients with different clinical manifestations of Lyme borreliosis. In seven of the patients, Borreliae were also isolated from skin lesions. Species identification and plasmid profiles were determined by pulsed-field gel electrophoresis and protein profiles by SDS-PAGE. MluI digestion profiles of Borrelia burgdorferi sensu lato DNA showed that 25 (62.5%) isolates were B. garinii, 14 (35%) B. afzelii, and one (2.5%) B. burgdorferi sensu stricto. All strains, except one, possessed a large plasmid and a varying number of smaller plasmids. Three (7.5%) isolates exhibited an unusual plasmid profile, with a large plasmid dimer or three copies of the large plasmid. In protein analyses, all strains expressed OspA protein. OspB was present significantly more often in B. afzelii than B. garinii strains (p=0.0000), while OspC was more often present in B. garinii than B. afzelii strains (p=0.0052). In the seven patients with Borreliae isolated also from the skin, the CSF and skin isolates were identical, either B. garinii (six patients) or B. afzelii (one patient). Species and plasmid heterogeneity as well as antigen diversity could play a role in the pathogenesis of the infection. When combined with our own earlier data, the results suggest species-related organotropism.  相似文献   

4.
Lyme borreliosis is the most prevalent tick-borne infection in Slovenia. Skin disorders are the most frequent clinical manifestations. The aim of the present study was to assess the phenotypic and genotypic diversity of a large number of human Borrelia burgdorferi sensu lato isolates and to evaluate any association between the isolates and different clinical manifestations. All 103 strains tested were from patients suffering from the skin disorders of Lyme borreliosis. Skin biopsies, cerebrospinal fluid and blood samples from patients were inoculated into modified Kelly Pettenkofer medium. Protein profiles were determined by SDS-PAGE and species identification and plasmid profiles by pulsed-field gel electrophoresis. MluI digestion profiles showed that 87 (84.5%) isolates belonged to B. afzelii, 15 (14.5%) to B. garinii and 1 (1%) to B. burgdorferi sensu stricto. The number of plasmids in each strain varied from three to seven, and the plasmid size ranged from 15 to 65 kb. Four isolates of B. garinii possessed multiple large plasmids and four isolates had a large plasmid dimer (three B. afzelii and one B. garinii). Isolates showed qualitative and quantitative differences in protein expression. The study found differences in the expression of OspB and OspC proteins between B. afzelii and B. garinii strains. OspB was expressed significantly more often by B. afzelii (78 of 87, 89.6%) than by B. garinii (4 of 15, 26.6%) isolates, while OspC protein was expressed significantly more often by B. garinii (14 of 15, 93.3%) than by B. afzelii (51 of 87, 58.6%) isolates. In Slovenia, B. afzelii causes the majority of skin lesions. The isolates investigated showed plasmid and protein diversity. Heterogeneity of the spirochaetes may be important for virulence, and may have implications for pathogenesis and therapy of the infection. Differences in immunodominant proteins also have an important impact on serological testing and vaccine development.  相似文献   

5.
Between 1993 and 1998, we isolated Borrelia burgdorferi sensu lato from 55 of the 119 patients with clinically diagnosed Lyme borreliosis who were admitted to "San Martino" Hospital in Belluno, Veneto, an Adriatic region in northeastern Italy where Lyme borreliosis is endemic. Upon hospitalization, all patients presented erythema migrans. Isolates were typed using ribosomal DNA PCR-restriction fragment length polymorphism (RFLP) analysis of the rrfA-rrlB intergenic spacer. Of the 41 isolates typed, 37 belonged to Borrelia afzelii, 2 to Borrelia garinii, and 2 to B. burgdorferi sensu stricto. Pulsed-field gel electrophoresis, performed on 21 strains (13 new isolates and 8 controls), revealed different RFLP patterns within the B. garinii and B. afzelii strains; among the five B. garinii strains and the 12 B. afzelii strains, three or two different RFLP patterns were identified, according to the restriction enzyme used. The protein patterns of the new isolates confirmed their genotypic classification and revealed the level of expression of some immunodominant proteins like OspA and other characteristic Osps. These findings constitute the first report of such a high recovery rate of B. burgdorferi from patients in a very restricted area in Italy; they also indicate the predominance of the genospecies B. afzelii in the study area and the heterogeneity of the circulating strains.  相似文献   

6.
A total of 46 Borrelia burgdorferi sensu lato isolates that were isolated from patients with Lyme borreliosis and infected animals or were extracted from ticks of the genus Ixodes were analyzed. Large restriction fragment patterns obtained after cleavage of genomic DNAs with MluI were analyzed by pulsed-field gel electrophoresis (PFGE). To eliminate the contribution of plasmid DNA, only fragments greater than 70 kb were used for the analysis. The results indicated that each of the 14 B. burgdorferi sensu stricto isolates were recognized by a band at 135 kbp, each of the 12 Borrelia garinii isolates by two bands (220 and 80 kbp), and each of the 20 Borrelia afzelii isolates by three bands (460, 320, and 90 kbp). Whereas differences in the PFGE patterns among B. burgdorferi sensu stricto isolates and B. garinii isolates were noted, B. afzelii isolates were all similar. Identification of isolates by PFGE correlates with their belonging to a given species within B. burgdorferi sensu lato.  相似文献   

7.
Detection of the Borrelia burgdorferi sensu lato complex in biological samples is currently done by conventional immunological and molecular biological methods. To improve on the accuracy of these methods and to simplify the procedure for testing large numbers of samples, a solid-phase sandwich hybridization system readily applicable to the detection of PCR products has been designed. This colorimetric detection system relies on the use of polybiotinylated detection probes and of specific capture oligonucleotides covalently linked at allocated positions on nylon membrane strips. From a phylogenetic analysis on a great number of ospA gene sequences, we have designed and synthesized a set of PCR primers specific to the five Borrelia burgdorferi sensu lato genospecies present in Europe and a subset of probes (capture and detection probes) specific to these five genospecies (B. burgdorferi sensu stricto, B. garinii, B. afzelii, B. valaisiana, and B. lusitaniae). This combined PCR hybridization system was evaluated with a large number of various B. burgdorferi isolates and clinical specimens. These analyses clearly showed that the system could be used as a typing method to distinguish five genospecies belonging to the B. burgdorferi sensu lato complex. In addition, the study showed that B. valaisiana strains might be more heterologous than suspected up to now and clustered into three genomic groups.  相似文献   

8.
Lyme borreliosis often presents initially with erythema migrans. Borreliae may disseminate from the primary skin lesion, and different organs and systems could be affected. Borrelia strains were isolated from blood of 70 patients with Lyme borreliosis, including 10 patients from whom borreliae were also isolated from skin. The aim of the present study was to characterise the isolates with regard to their phenotypic and genotypic characteristics. Borreliae were cultivated in MKP medium. Species identification and plasmid profiles were determined by pulsed-field gel electrophoresis (PFGE) and protein profiles by SDS-PAGE. Digestion of Borrelia burgdorferi sensu lato DNA showed 63 (90%) B. afzelii Mla1 and 7 (10%) B. garinii Mlg2. No B. burgdorferi sensu stricto were isolated. Borreliae were isolated from both skin and blood of 10 patients, nine pairs of isolates were identical: seven B. afzelii and two B. garinii. B. afzelii was isolated from the skin and B. garinii from blood of the tenth patient. All but one isolate possessed at least one large plasmid and varying numbers of smaller plasmids. Eight (11.4%) of 70 isolates possessed an unusual plasmid profile (2 of 63 B. afzelii and 6 of 7 B. garinii). Borreliae differed in their protein profiles. OspA and OspB proteins were expressed by all B. afzelii isolates; 85.7% of B. garinii isolates expressed OspA and 71.4% expressed OspB. OspC was expressed by 65% of B. afzelii isolates and all B. garinii isolates. The ratios of B. afzelii and B. garinii isolated from blood and skin were similar. These results do not support the hypothesis that B. garinii has a higher propensity for haematogenous dissemination than B. afzelii. Antigen diversity as well as species and plasmid heterogeneity could play a role in the pathogenesis of the infection, suggesting distinctive strain organotropism.  相似文献   

9.
To differentiate the Borrelia burgdorferi sensu lato genospecies, LightCycler real-time PCR was used for the fluorescence (SYBR Green I) melting curve analysis of borrelial recA gene PCR products. The specific melting temperature analyzed is a function of the GC/AT ratio, length, and nucleotide sequence of the amplified product. A total of 32 DNA samples were tested. Of them three were isolated from B. burgdorferi reference strains and 16 were isolated from B. burgdorferi strains cultured from Ixodes ricinus ticks; 13 were directly isolated from nine human biopsy specimens and four I. ricinus tick midguts. The melting temperature of B. garinii was 2 degrees C lower than that of B. burgdorferi sensu stricto and B. afzelii. Melting curve analysis offers a rapid alternative for identification and detection of B. burgdorferi sensu lato genospecies.  相似文献   

10.
A DNA microarray containing fragments of 137 Borrelia burgdorferi B31 putative lipoprotein genes was used to examine Lyme disease spirochetes. DNA from B. burgdorferi sensu stricto B31, 297, and N40; Borrelia garinii IP90; and Borrelia afzelii P/Gau was fluorescently labeled and hybridized to the microarray, demonstrating the degree to which the individual putative lipoprotein genes were conserved among the genospecies. These data show that a DNA microarray can globally examine the genes encoding B. burgdorferi lipoproteins.  相似文献   

11.
We report the results of a study of the prevalences of three clinically relevant Borrelia burgdorferi sensu lato genospecies (Borrelia burgdorferi sensu stricto, Borrelia afzelii, and Borrelia garinii) in 1,040 questing Ixodes ticks from all regions of Latvia, where Lyme borreliosis is endemic. The prevalences of Borrelia in Ixodes ricinus and Ixodes persulcatus were 22.6 and 27.9%, respectively. Molecular typing of B. burgdorferi from infected ticks was performed by restriction fragment length polymorphism (RFLP) analysis of PCR-amplified fragments of the 16S-23S (rrs-rrlA) rRNA intergenic spacer by using species-specific primers and subsequent sequencing. The dominant Borrelia species in both Ixodes species was B. afzelii. In addition, different restriction patterns of B. garinii and B. afzelii were also identified. This study demonstrates that the 16S-23S rRNA PCR-RFLP typing method is simple, sensitive, and fast and that it allows one to differentiate among B. burgdorferi species and subspecies with various degrees of pathogenic potential directly in ticks. These features are important in monitoring Lyme disease.  相似文献   

12.
Oligonucleotide primers based on Borrelia burgdorferi sensu lato ospA gene sequences have been designed for use in the PCR to type all (SL primers) or each (GI to GIII primers) of the B. burgdorferi sensu lato genospecies involved in Lyme disease. These genospecies-specific primers were then used in the PCR on 24 biological fluids collected from 18 neuroborreliosis patients. Among the samples tested, 20 contained DNA from Borrelia garinii, 11 contained DNA from B. burgdorferi sensu stricto, and 10 contained DNA from Borrelia afzelii. In toto, 10 patients appeared to have been infected by a single genospecies and 8 were infected by more than one Lyme disease-associated genospecies. Serum specimens from six patients were absorbed with heterologous antigens and tested by Western blotting (immunoblotting). In four cases, residual immunodetection revealed specific epitopes of genospecies also detected by PCR; in two of them, the concordant results indicated pluri-infection of the patients. In the other two cases, Western blotting showed specific antibodies for two genospecies of Borrelia, while PCR detected DNA from only one. In summary, the data underscored the relatively high prevalence of pluri-infections in Lyme disease and confirmed the association of B. garinii with neuroborreliosis.  相似文献   

13.
Objective: To evaluate by species-specific immunoblots the association of Borrelia burgdorferi sensu stricto, B. garinii and B. afzelii with neuroborreliosis in Switzerland.
Methods: Borrelia strains isolated from the cerebrospinal fluid (CSF) of three children with neuroborreliosis were typed by phenotypic and genotypic analysis. The serologic reactions (IgG) of these three patients as well as those of 28 patients, including one of these three children, with confirmed neuroborreliosis were characterized and scored by immunoblots on the three individual Borrelia species antigens. Twenty patients with typical erythema migrans served as a control group.
Results: Phenotypic and genotypic analysis confirmed that all three CSF isolates were B. garinii. In the 28 patients with neuroborreliosis, the comparatively strongest reactions were as follows: 18 to B. garinii , three to B. burgdorferi sensu stricto and two to B. afzelii ; five were inconclusive. In the control group (erythema migrans), the comparatively strongest reactions were as follows: six B. garinii , one to B. burgdorferi sensu stricto and five to B. afzelii ; eight were indeterminate.
Conclusions: Typing of these three CSF isolates and characterization by immunoblots of the antibody reactions of patients with neuroborreliosis give additional evidence of the association of B. garinii and neuroborreliosis. Our serologic results suggest that B. burgdorferi sensu stricto and B. afzelii are also responsible for some neuroborreliosis cases in Switzerland. Our immunoblots and the scoring system proved particularly useful for the serologic typing of patients with late Lyme borreliosis.  相似文献   

14.
The most characteristic features of the Lyme disease pathogens, the Borrelia burgdorferi sensu lato (s.l.) group, are their ability to invade tissues and to circumvent the immune defenses of the host for extended periods of time, despite elevated levels of borrelia-specific antibodies in serum and other body fluids. Our aim in the present study was to determine whether B. burgdorferi is able to interfere with complement (C) at the level of C3 by accelerating C3b inactivation and thus to inhibit the amplification of the C cascade. Strains belonging to different genospecies (Borrelia garinii, B. burgdorferi sensu stricto, and Borrelia afzelii) were compared for their sensitivities to normal human serum and abilities to promote factor I-mediated C3b degradation. B. burgdorferi sensu stricto and B. afzelii strains were found to be serum resistant. When the spirochetes were incubated with radiolabeled C3b, factor I-mediated degradation of C3b was observed in the presence of C-resistant B. afzelii (n = 3) and B. burgdorferi sensu stricto (n = 1) strains but not in the presence of C-sensitive B. garinii (n = 7) strains or control bacteria (Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis). Immunoblotting and radioligand binding analyses showed that the C-resistant strains had the capacity to acquire the C inhibitors factor H and factor H-like protein 1 (FHL-1) from growth medium and human serum. A novel surface protein with an apparent molecular mass of 35 kDa was found to preferentially bind to the N terminus region of factor H. Thus, the serum-resistant B. burgdorferi s.l. strains can circumvent C attack by binding the C inhibitors factor H and FHL-1 to their surfaces and promoting factor I-mediated C3b degradation.  相似文献   

15.
The molecular and antigenic variabilities of BmpA (P39) among European isolates of Borrelia burgdorferi were analyzed. The bmpA sequences of 12 isolates representing all three species of B. burgdorferi sensu lato pathogenic for humans were amplified by PCR, cloned, and sequenced. The BmpA protein of Borrelia garinii is heterogeneous, with an amino acid sequence identity ranging from 91 to 97%, whereas the BmpA proteins of Borrelia afzelii and B. burgdorferi sensu stricto strains appear to be highly conserved (>98.5% intraspecies identity). The interspecies identities ranged from 86 to 92%. Cluster analysis of BmpA reflected the subdivision of B. burgdorferi sensu lato isolates into the three species as well as a considerable heterogeneity among B. garinii strains. The BmpA protein of each species of B. burgdorferi sensu lato was recombinantly expressed in Escherichia coli, purified, and used to generate monoclonal antibodies. Seven BmpA-specific antibodies were identified; six of them recognized conserved epitopes of all three species, whereas one was specific for BmpA of B. afzelii and B. garinii. A monoclonal antibody (H1141) recommended by the Centers for Disease Control and Prevention for use in the standardization of immunoblots showed strong reactivity with BmpA of B. burgdorferi sensu stricto but no or only weak reactivity with BmpA of B. garinii and B. afzelii, respectively. Sera from 86 European patients with Lyme borreliosis in different stages and 73 controls were tested in immunoglobulin G (IgG) and IgM immunoblots with the recombinant BmpA proteins of the three species, revealing specificities of 98.6 to 100%. IgM antibodies against recombinant BmpA were only rarely detected (1.1 to 8.1%). With the BmpA proteins of B. afzelii and B. garinii, sensitivities for the IgG test (sera from stages I to III) were 36.0 and 34.9%, respectively, in contrast to 13.9% with BmpA of B. burgdorferi sensu stricto. Therefore, we recommend that recombinant BmpA of B. afzelii or B. garinii should be used solely, or in addition to B. burgdorferi sensu stricto BmpA, in serodiagnostic tests for Lyme borreliosis in Europe.  相似文献   

16.
A LightCycler-based PCR protocol was developed which targets the ospA gene for the identification and quantification of the different Borrelia burgdorferi sensu lato species in culture and in ticks, based on the use of a fluorescently labeled probe (HybProbe) and an internally labeled primer. The detection limit of the PCR was 1 to 10 spirochetes. A melting temperature determined from the melting curve of the amplified product immediately after thermal cycling allowed the differentiation of the three different B. burgdorferi sensu lato genospecies (B. burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii) that are clinically relevant in Europe in a single PCR run. This method represents a simplified approach to study the association of different Borrelia species in ticks, the risk of Lyme borreliosis, and the putatively species-specific clinical sequelae. To determine the reliability of the real-time PCR protocol, we studied the prevalence of B. burgdorferi sensu lato infection in Ixodes ricinus ticks. A total of 1,055 ticks were collected by flagging vegetation in five different sites in the region of Konstanz (south Germany) and were examined for the distribution of B. burgdorferi species by real-time PCR. The mean infection rate was 35%. Of 548 adult ticks, 40% were positive, and of 507 nymphs, 30% were positive. The predominant genospecies (with 18% mixed infections) in the examined areas was B. afzelii (53%), followed by B. garinii (18%) and B. burgdorferi sensu stricto (11%); 0.8% of the infecting Borrelia could not be identified.  相似文献   

17.
Molecular analyses of the genes encoding OspC, a major immunodominant protein of Borrelia burgdorferi sensu lato, revealed a considerable degree of heterogeneity. In the present study, we investigated whether a similar heterogeneity of the OspC phenotype can be shown by analysis with monoclonal antibodies (MAbs). Thirteen OspC-specific MAbs (L22 MAbs) were produced by immunizing mice with either different combinations of whole-cell antigens or recombinantly expressed OspCs cloned from strains belonging to different Borrelia spp. Ten of them differed in their reactivities with various strains. Western blot (immunoblot) analyses of 38 B. burgdorferi sensu lato strains resulted in 13 different reactivity patterns. These 13 different patterns were observed among only six different OspA serotypes, indicating that OspC is more heterogeneous than OspA. Patterns 1 to 4 were present only in B. burgdorferi sensu stricto, patterns 5 to 7 were present only in Borrelia afzelii, and patterns 9 to 13 were present only in Borrelia garinii. Pattern 8 was observed among B. afzelii and B. garinii strains but not among B. burgdorferi sensu stricto strains. One L22 MAb (2B8) recognized a common OspC-specific epitope of all 38 B. burgdorferi sensu lato strains analyzed, and another one (22C11) recognized a common epitope of OspC from both B. afzelii and B. garinii and was not reactive with OspC from B. burgdorferi sensu stricto. Western blot and sequence analysis of truncated OspCs located the 22C11 epitope as well as a species-specific sequence motif between amino acids 20 and 35.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
The growth of 29 human strains from the three main pathogenic species of Borrelia burgdorferi sensu lato on a solid BSK-based medium was compared in two culture atmospheres: 3% CO(2) air and anaerobiosis. All strains grew under anaerobic conditions, whereas only 13 strains were able to grow in aerobiosis with 3% CO(2) (P<0.001). In the latter condition, 75% of the B. burgdorferi sensu stricto strains grew versus 33% of the B. garinii and B. afzelii strains. These data suggest that, especially for B. garinii and B. afzelii species, anaerobic conditions enhance growth yield and speed of low-passage Borrelia strains.  相似文献   

19.
To further investigate the pathogenic potential of different Borrelia burgdorferi genospecies, specimens from 27 patients with different manifestations of Lyme borreliosis were analyzed by PCR and reverse line blotting (RLB). In samples from Lyme arthritis patients, B. burgdorferi sensu stricto was predominantly identified, while in patients with neuroborreliosis or acrodermatitis, Borrelia garinii and Borrelia afzelii, respectively, were exclusively detected. The results demonstrate that PCR-RLB is a valuable tool for epidemiological and pathogenetic studies of Lyme borreliosis.  相似文献   

20.
An immunoglobulin G immunoblot was developed with antigenic extracts of Borrelia burgdorferi sensu stricto, B. garinii, B. afzelii, and B. valaisiana genospecies and was reacted with sera from patients with neuroborreliosis, acrodermatitis, and Lyme arthritis. A detailed analysis of the reactivities of the protein bands was performed, and a two-step scoring procedure was selected to determine the preferential reactivity of sera to one particular genospecies. The discriminative potential of 5 proteins (12-kDa, 16-kDa, 18-kDa, OspA, and 66-kDa proteins) was used as a rapid first-step scoring method, followed by scoring of 14 additional protein bands if necessary. The advantage of this procedure is the low percentage of serum samples with inconclusive results for one of the four species (10% for patients with neuroborreliosis, 6% for patients with acrodermatitis chronica atrophicans, and 6% for patients with Lyme arthritis). Among 31 serum samples from patients with neuroborreliosis, 16 were more reactive to B. garinii, 7 were more reactive to B. afzelii, 3 were more reactive to B. valaisiana, and 2 were more reactive to B. burgdorferi sensu stricto. Of 31 serum samples from patients with acrodermatitis, 26 showed a higher level of reactivity to B. afzelii. Of 34 serum samples from patients with Lyme arthritis, 21 were more reactive to B. burgdorferi sensu stricto, 10 were more reactive to B. afzelii, and 1 was more reactive to B. valaisiana. Our results suggest an organotropism of Borrelia species and provide some evidence of a pathogenic potential of B. valaisiana in humans.  相似文献   

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