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21.
A real-time PCR assay targeting the capsulation locus of Haemophilus influenzae type b (Hib) was developed. The linear detection range was from 1 to 10(6) microorganisms per reaction mixture. No H. influenzae other than Hib or any other control bacteria typically found in the upper respiratory tract was detected.  相似文献   
22.
The human malignant pleural mesothelioma is related to the use of asbestos in the majority of cases. Though the use of asbestos has been prohibited since the 1990s, the incidence of pleural mesothelioma is still increasing because of a latency period of at least 20 years. This study investigated the benefit of single therapy with cyclophosphamide or hyperthermia or the combination of both on cells of a human pleural mesothelioma cell line, xenotransplanted subcutaneously in the paw of mice. A CONTROL group received the same volume of physiological saline. The oxygenation of tumours was measured, tumour growth was followed over 3 weeks, immunohistochemical studies and a light and electron microscopic evaluation were performed. Chemotherapy or hyperthermia alone was only temporarily effective. The greatest benefit was achieved using combined thermochemotherapy consisting of cyclophosphamide plus hyperthermia: 50% of this group had partial remissions, and 67% responded to this therapy. After 3 weeks tumours grew again. Superior effects could be achieved by performing additional cycles of chemotherapy or adding another drug or radiation for instance. This study shows promising results in the treatment of malignant pleural mesothelioma.  相似文献   
23.
The pitch identification performance of absolute pitch possessors has previously been shown to depend on pitch range, key color, and timbre of presented tones. In the present study, the dependence of pitch identification performance on key color and timbre of musical tones was examined by analyzing hit rates, reaction times, and pupillary responses of absolute pitch possessors (n = 9) and nonpossessors (n = 12) during a pitch identification task. Results revealed a significant dependence of pitch identification hit rate but not reaction time on timbre and key color in both groups. Among absolute pitch possessors, peak dilation of the pupil was significantly dependent on key color whereas the effect of timbre was marginally significant. Peak dilation of the pupil differed significantly between absolute pitch possessors and nonpossessors. The observed effects point to the importance of learning factors in the acquisition of absolute pitch.  相似文献   
24.
From Escherichia coli PCM 271 cells two penicillin amidases were separated by affinity chromatography on immunoadsorbent column. In cells grown in organic medium the activities of the amidase 1 and 2 were 30 and 70% respectively, whereas the activity of the amidase 1 in the cells grown in inorganic medium increased up to 98%. The amidase 1 migrated faster in polyacrylamide gel electrophoresis and was retained on DEAE-cellulose in 10 mM phosphate buffer, pH 8. No catalytic differences were demonstrated between the amidases.  相似文献   
25.
A typology of 156 convicted driving-while-intoxicated (DWI) offenders was developed using cluster analysis and external validation procedures. The typology was derived from 4 variables (alcohol dependence severity, psychiatric severity, bad-driving index, and social instability) selected to maximize the feasibility of performing treatment matching with DWI offenders. Five clusters that suggested specific treatment matching opportunities were identified. The largest, Cluster 4 (31% of cases), showed a low problem profile. However, a moderate-severity group (Cluster 1), a high-risk driver group (Cluster 2), and two high problem-severity groups (Clusters 3 and 5) were also found. Clusters 3 and 5 had high levels of alcohol dependence and psychiatric symptoms but differed significantly on social instability.  相似文献   
26.
The Fc gamma receptor of guinea-pig peritoneal macrophages was purified by affinity chromatography by using rabbit IgG or guinea-pig IgG2 coupled to Sepharose. Lysates prepared by treatment of 125I-labeled macrophages with NP-40 were first applied to BSA-Sepharose and then to IgG-Sepharose and eluted with 0.5 M acetic acid containing 1% NP-40. The specific binding was determined by interaction of the 125I-labeled receptor with IgG-Sepharose in the presence and absence of soluble IgG. The specific binding of the purified receptor was 42-82%. Interactions of the purified receptor with IgG-Sepharose were equally well inhibited by soluble rabbit IgG or guinea-pig IgG2, but not by F(ab')2 fragments. Inclusion of NP-40 in the buffer used in the assay reduced nonspecific binding of the receptor to the affinity gels. The purified receptor can be stored for 20 days at 4 degrees C without a significant loss of the specific binding activity. Analysis of the receptor by SDS-polyacrylamide gel electrophoresis, under nonreducing and reducing conditions, revealed two major peaks of radioactivity corresponding to mol. wts of about 50,000 and 25,000, and one very minor peak corresponding to a mol. wt of about 30,000. The results obtained suggest that the protein of the second major peak is a product of the dissociation of the protein of the first major peak rather than a product of its reduction by 2-mercaptoethanol.  相似文献   
27.
Virulent, viable Shigella sonnei bacilli introduced orally, induced in mice resistance against lethal intravenous (i.v.) infection with dysentery bacilli. The immunized animals survived lethal infection and also bacilli were effectively destroyed in the spleen and liver of the immunized animals. It was shown that orally induced immunity may be transferred into nonimmunized mice by means of serum and spleen cells taken on definite days after immunization of donors. Protective activity of serum appeared to be dependent on the presence of specific antibodies and was correlated with their titer. Protective activity of spleen cells occurred about 6 days after immunization of the cell donors with the bacilli. Cell suspensions, prepared from the spleens taken from donors on day 6, protected 100% of the recipients of these cells from lethal infection. Results of these studies indicate that bacterial infection developing in the intestine mobilizes besides local immunity also general immunity. Mechanism of the general immunity induced by orally administered dysentery bacilli is discussed.  相似文献   
28.
Our knowledge about the kinetics and dynamics of complex pathogen-specific CD8(+) T cell responses and the in vivo development of CD8(+) memory T cells has increased substantially over the past years; in comparison, relatively little is known about the CD4(+) T cell compartment. We monitored and directly compared the phenotypical changes of pathogen (Listeria monocytogenes)-specific CD8(+) and CD4(+) T cell responses under conditions leading to effective and long-lasting protective immunity. We found that the general kinetics of bacteria-specific CD8(+) and CD4(+) T cells during the effector and post-effector phases are synchronized. However, later during the memory phase, CD8(+) and CD4(+) T cell populations differ substantially. Whereas CD8(+) memory T cell populations with immediate effector function are readily detectable in lymphoid and non-lymphoid tissues and remain remarkably stable in size, antigen-specific CD4(+) effector-memory T cells decline continuously in frequency over time. These findings have important implications for the better understanding of the in vivo development of protective immunity towards intracellular pathogens.  相似文献   
29.
Mitogenic properties of a proline-rich polypeptide were investigated. The mitogenic action of PRP was compared with the mitogenic action of Il-1. PRP was not mitogenic for thymocytes at doses 0.01-50 micrograms/ml. PRP, at doses 0.1-50 micrograms/ml, augmented the proliferative response of thymocytes to Con A in a similar fashion as Il-1. At doses higher than 10 micrograms/ml, PRP induced proliferation of lymph node cells and splenocytes as well as T cells from the lymph nodes. It did not, however, cause significant proliferation of B cells from the lymph nodes, at the doses used. PRP did not induce proliferation of an antigen specific Lyt 1+ T cell clone. Il-1 behaved in a similar way as PRP in all the tests described. We consider a possibility that under physiological conditions, at a very early stage of postneonatal life, PRP may replace some functions of Il-1.  相似文献   
30.
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