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1.
Immunosuppressive effects of cyclosporin A (CsA) and FK 506 (FK) on peripheral blood lymphocytes were studied in dogs in respect to mixed lymphocyte reaction, proliferative responses to recombinant interleukin-2 (rIL-2), phytohemagglutinin (PHA) and concanavalin-A (Con-A); phenotypes of OKIa1, CD3, CD8 and surface IgM; cytotoxic activity against xenogeneic tumor cells. CsA (2.0 or 5.0 mg/kg, intravenously) or FK (0.16 mg/kg, intramuscularly) was given to mongrel dogs every morning for serial 21 days. The blood concentrations of CsA, measured as trough levels by fluorescence polarization method, ranged from 37 to 350 ng/ml in dogs administered at 2.0 mg/kg and from 170 to 894 ng/ml in dogs administered at 5.0 mg/kg during treatment, respectively. In dogs treated with FK at a dose of 0.16 mg/kg, the drug concentrations in the plasma during treatment ranged from 0.16 to 1.8 ng/ml. Mixed lymphocyte reaction and proliferative responses to rIL-2, PHA and Con-A, which were declined by CsA, were not affected by FK. In contrast, the proportion of OKIa1+ cells was not affected by CsA, whereas FK decreased the proportion of OKIa1+ cells progressively during the course of treatment. Cytotoxic activity was suppressed by both CsA and FK. These results possibly indicate that CsA and FK exert their immunosuppressive effects via different mechanisms.  相似文献   
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Using the technique of allele-specific priming of the polymerase chain reaction (PCR), the C-T substitution in codon 39 was identified as the cause of -thalassaemia in an Irish family. Analysis of the restriction fragment length polymorphisms (RFLPs) in the -globin gene cluster established linkage of the -thalassaemia mutation to a particular -haplotype but indicated that a recombinational event had occurred in the paternal chromosome in the younger of two affected children. Non-paternity was excluded by DNA fingerprinting analysis with hypervariable minisatellite probes. This is the fourth case of recombination in the -globin gene cluster to be reported. The event has occurred 5 of the polymorphic RsaI site at position-550 bp upstream of the -globin gene mRNA Cap site, within the 9.1-kb region that has been shown to be a hot spot for recombination in the -globin gene cluster.  相似文献   
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This study identifies the main changes in protein expression in human breast tumors compared to normal breast tissue. Malignant tumors (32) and normal breast tissue samples (23), from formaldehyde‐fixed, paraffin‐embedded specimens are subjected to discovery proteomics using liquid chromatography/tandem mass spectrometry, with spectral counts for quantitation. The dataset contains 1406 proteins. Differential expression is measured using a method that takes advantage of estimates of the percentage of tumor on a slide. This analysis shows that the major classes of proteins over‐expressed by tumors are RNA‐binding, heat shock and DNA repair proteins. RNA‐binding proteins, including heterogeneous nuclear ribonucleoproteins (HNRNPs), SR splice factors (SRSF) and elongation factors form the largest group. Comparison with results from another study demonstrates that the RNA‐binding proteins are associated specifically with malignant transformation, rather than with cell proliferation. HNRNP and SRSF proteins help define splice sites in normal cells. Their over‐expression may dysregulate splicing, which in turn has the potential to promote malignant transformation.  相似文献   
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Although Myanmar exports millions of dollars of rattan cane each year, the last systematic treatment of rattans in this country was done over 100 years ago, and virtually nothing has been written about the collection and trade of this important forest resource. Here we report the results from a study of rattans in the Hukaung Valley Tiger Reserve in northern Myanmar. A total of 15 species of rattan were encountered; seven species are new records for Myanmar and two species are new to science. Inventory transects revealed that the density of commercial rattans in local forests averages 40.5 canes ≽4m long/hectare. Populations of all species appear to be actively regenerating. The current pattern of rattan exploitation, however, is largely uncontrolled and will eventually lead to resource depletion unless some form of management is implemented.  相似文献   
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Background

Leptospirosis is an emerging zoonosis that is often under-recognized in children and commonly confused with dengue in tropical settings. An enhanced ability to distinguish leptospirosis from dengue in children would guide clinicians and public health personnel in the appropriate use of limited healthcare resources.

Methodology/Principal Findings

We conducted a prospective, hospital-based, study of children with acute febrile illnesses and dengue in Thailand. Among the children without dengue, we identified those with leptospirosis using anti-leptospira IgM and microscopic agglutination titers in paired acute and convalescent blood samples. We then performed a case-control comparison of symptoms, signs, and clinical laboratory values between children with leptospirosis and dengue.In a semi-rural region of Thailand, leptospirosis accounted for 19% of the non-dengue acute febrile illnesses among children presenting during the rainy season. None of the children with leptospirosis were correctly diagnosed at the time of hospital discharge, and one third (33%) were erroneously diagnosed as dengue or scrub typhus. A predictive model to distinguish pediatric leptospirosis from dengue was generated using three variables: the absolute neutrophil count, plasma albumin, and aspartate aminotransferase levels in the first 72 hours of illness.

Conclusions/Significance

Unrecognized leptospirosis can be a significant cause of “dengue-like” febrile illness in children. Increased awareness of pediatric leptospirosis, and an enhanced ability to discriminate between leptospirosis and dengue early in illness, will help guide the appropriate use of healthcare resources in often resource-limited settings.  相似文献   
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Mycoplasma haemocanis (formerly Haemobartonella canis) is a red blood cell parasite that causes disease mainly in immunosuppressed and splenectomized dogs. Clinical outbreak of the disease resulted in failure of a large experimental project. We aimed to identify whether M. haemocanis has increased prevalence in kennel-raised dogs. In a prospective study, we compared the prevalence of M. haemocanis in whole blood (anti-coagulated by use of EDTA) collected from pet dogs (University of Illinois, Urbana Champaign, Ill.; n = 60) with that in blood from dogs raised in three distinct kennels in western Europe (WE; n = 23), eastern Europe (EE; n = 20), and North America (NA; n = 20). Screening included antibody testing and microscopy of blood smears. The presence of M. haemocanis was identified using a polymerase chain reaction (PCR) assay for specific DNA of the organism. None of the pet dogs (0%) was test positive for M. haemocanis DNA. Mycoplasma haemocanis was found in dogs tested at all of the kennels. Infection rate in the three kennels was 30, 35, and 87%, respectively (all P < 0.001 versus control, chi2-test). Latent infection with M. haemocanis was not a single observation in kennel-raised dogs. Prevalence may be higher than that in a pet dog population. The potential exists for these latent infections to adversely affect or confound research results.  相似文献   
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