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21.
Tortoriello DV; McGovern PG; Colon JM; Loughlin J; Santoro N 《Human reproduction (Oxford, England)》1998,13(11):3005-3008
We report an instance of critical ovarian hyperstimulation syndrome in a
highly responsive in-vitro fertilization patient despite the preventive
measure of a 4 day 'coast' interval during which no gonadotrophins were
administered while gonadotrophin-releasing hormone agonist therapy
continued until serum oestradiol concentrations fell below 3000 pg/ml.
相似文献
22.
23.
Middleton JR Fales WH Luby CD Oaks JL Sanchez S Kinyon JM Wu CC Maddox CW Welsh RD Hartmann F 《Journal of clinical microbiology》2005,43(6):2916-2919
Staphylococcus aureus isolates (n = 70) from 65 patients (36 canine, 18 equine, 7 bovine, 2 avian, and 2 feline) at seven veterinary teaching hospitals in the United States were studied. The majority of patients (83%) with an S. aureus infection were canine and equine, but this may have reflected a sample bias based on clinic case loads and diagnostic lab submissions at the participating institutions. Fourteen percent of patients with an S. aureus infection were infected with a methicillin-resistant S. aureus (MRSA) isolate. Six of seven institutions had at least one MRSA infection during the study. Pulsed-field gel electrophoresis on 63 of the 70 isolates yielded 58 unique strains of S. aureus. None of the strain types of the MRSA isolates matched each other or the type of any other S. aureus isolate. The proportions of patients infected with an MRSA isolate were not significantly different between institutions or animal species (P > or = 0.222). Methicillin-resistant S. aureus isolates in this study seemed to be community acquired rather than hospital acquired. 相似文献
24.
Length polymorphisms in tRNA intergenic spacers detected by using the polymerase chain reaction can distinguish streptococcal strains and species. 下载免费PDF全文
Intergenic tRNA spacers from strains of streptococcal groups A, B, and G were amplified by using the polymerase chain reaction (PCR) at low stringency with consensus tRNA gene primers. Cloning and sequencing showed that many of the homologous intergenic spacers differed in length between species. The sequences of the tRNA genes that flank these polymorphic spacers were determined and used to synthesize fully complementary primers. With these primers at high stringency, PCR products which varied in lengths from 53 to 71 bp, depending on the species or strain, were obtained from streptococcal DNAs, even in the presence of a 1,000-fold mass excess of human DNA. PCR products, the lengths of which could also be used for classification, were obtained at high stringency from a few genera closely related to Streptococcus. No products were obtained from genomic DNAs from more distantly related genera. Production of species- or strain-specific tRNA intergenic length polymorphisms with primers that generate characteristic products from a variety of species within the same genus should be applicable to many organisms, including those that would otherwise be difficult to culture or identify. 相似文献
25.
Generation of CD8(+) T-cell responses to Mycobacterium bovis and mycobacterial antigen in experimental bovine tuberculosis 下载免费PDF全文
Protective immunity against tuberculosis is considered to be essentially cell mediated, and an important role for CD8(+) T lymphocytes has been suggested by several studies of murine and human infections. The present work, using an experimental model of infection with Mycobacterium bovis in cattle, showed that live M. bovis elicits the activation of CD8(+) T cells in vitro. However, a sonic extract prepared from M. bovis (MBSE) and protein purified derivative (PPDb) also induced a considerable degree of activation of the CD8(+) T cells. Analysis of proliferative responses of peripheral blood mononuclear cells, purified CD8(+) T cells, and CD8(+) T-cell clones to M. bovis and to soluble antigenic preparations (MBSE, PPDb) showed that the responses of all three types of cells were always superior for live mycobacteria but that strong responses were also obtained with complex soluble preparations. Furthermore, while cytotoxic capabilities were not investigated, the CD8(+) T cells were found to produce and release gamma interferon in response to antigen (live and soluble), which indicated one possible protective mechanism for these cells in bovine tuberculosis. Finally, it was demonstrated by metabolic inhibition with brefeldin A and cytochalasin D at the clonal level that an endogenous pathway of antigen processing is required for presentation to bovine CD8(+) cells and that presentation is also dependent on phagocytosis of the antigen. 相似文献
26.
L Vera-Cabrera M C Salinas-Carmona O Welsh M A Rodriguez 《Journal of clinical microbiology》1992,30(5):1183-1188
Two immunogenic proteins from a crude extract of Nocardia brasiliensis were purified to homogeneity. A 61-kDa protein (P61) was isolated from a 50% ammonium sulfate precipitate in two steps. Initially, P61 was obtained by electroelution in a 10% nondenatured preparative polyacrylamide gel electrophoresis (PAGE). In a second step, the eluate from the nondenatured gel was run in a 12% sodium dodecyl sulfate (SDS) preparative polyacrylamide gel. After elution, a single band was demonstrated by SDS-PAGE and Western blot (immunoblot). Also, a 24-kDa immunogenic protein (P24) was isolated by gel filtration in a Sephadex G-100 column and then by electroelution in a 12% nondenatured polyacrylamide gel. In a previous paper, we showed by Western blot assays that these proteins are recognized by the sera of mycetoma patients and not by sera from mycobacterial-infected or healthy individuals. We consider these proteins to be good candidates for the study of the host-parasite relationship in nocardial infections. The possible clinical application of these purified antigens in a serological diagnosis is discussed. 相似文献
27.
28.
Immunoglobulin heavy chain switch region restriction fragment length polymorphisms are associated with renal disease. 总被引:3,自引:1,他引:3
A G Demaine D H Taube R W Vaughan L A Kerr K I Welsh 《Clinical and experimental immunology》1986,66(2):406-413
We describe here, to our knowledge for the first time, associations between polymorphisms at the genomic DNA level in the immunoglobulin gene region and renal diseases which lead to chronic renal failure. Recent studies have shown that protein polymorphisms, present in immunoglobulin (Ig) heavy chains (Gm allotypes) are associated with certain forms of renal disease and with end stage renal failure per se. To investigate this association at the DNA level we have used probes which recognize Ig heavy chain genes and this report describes results obtained with one of these, the S mu switch region probe. With the restriction endonuclease Sst 1 (or the isoschizomer; Sac I) a number of restriction fragment length polymorphisms (RFLP) can be obtained which are recognized by this probe and there is a highly significant association between certain of these and renal disease. This is the first report of Ig switch region polymorphisms being associated with disease, yet our results suggest that S mu RFLP are more closely linked to renal disease than Ig protein polymorphisms. 相似文献
29.
Notch signaling regulates left-right asymmetry determination by inducing Nodal expression 总被引:1,自引:0,他引:1 下载免费PDF全文
30.
Battaglia C; Artini PG; Giulini S; Salvatori M; Maxia N; Petraglia F; Volpe A 《Human reproduction (Oxford, England)》1997,12(11):2477-2482
The objective of this study was to evaluate the Doppler flow variations
which occur following the use of different protocols of ovarian stimulation
in an IVF programme, and to investigate the thromboxane production by
cultured endometrial cells and its influence on embryo implantation. A
total of 60 patients underwent three different ovarian stimulation
protocols: long gonadotrophin-releasing hormone agonist (GnRH-a), short
GnRH-a and no GnRH-a. Transvaginal ultrasonography and colour Doppler
analysis were performed before and during the treatment. On the day that
the Doppler examination took place, luteinizing hormone, follicle
stimulating hormone, plasma oestradiol and thromboxane concentrations were
assayed. On the day of oocyte retrieval, endometrial cells were collected
and cultured, and their thromboxane production evaluated. No significant
differences in hormonal, ultrasonographic or Doppler parameters were
observed between the three groups. Ten out of 56 patients who had a
successful embryo transfer became pregnant. In the group of pregnant women
the pulsatility index values of both uterine and spiral arteries was lower
than in non-pregnant patients, and was associated with significantly lower
thromboxane concentrations from cultured endometrial cells. It is concluded
that thromboxane plays a role in embryo implantation, and that Doppler flow
analysis of uterine and spiral arteries in infertile patients may be
important in the management of ovarian stimulation.
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