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11.
This case report describes a successful pregnancy and deliveryin a woman presenting with ovarian autoimmunity who had previouslybeen involved in two unsuccessful in-vitro fertilization (IVF)attempts. Ten days before a third attempt, she began a regimenof 25 mg per day of prednisolone which was continued throughoutthe whole IVF protocol. Ovulation was induced by human menopausalgonadotrophin. After administration of 5000 IU of human chorionicgonadotrophin, 18 oocytes were collected. At 48 h after inseminationwith the patient's husband's spermatozoa, four 4-cell pre-embryoswere transferred. A singleton pregnancy developed and led tothe birth of a girl who is doing well 10 months later.  相似文献   
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Background: The effects of epidural needle design, angle, and bevel orientation on cerebrospinal fluid leak after puncture have not been reported. The impact of these factors on leak rate was examined using a dural sac model. Dural trauma was examined using scanning electron microscopy.

Methods: Human cadaveric dura, mounted on a cylindrical model, was punctured with epidural needles using a micromanipulator. Tissue was punctured at 15 cm H2O (left lateral decubitus) system pressure, and leak was measured at 25 cm H2O (semisitting) pressure. Leak rates and trauma were compared for the following: (1) six different epidural needles at 90[degrees], bevel parallel to the dural long axis; (2) 18-gauge Tuohy and 18-gauge Special Sprotte(R) epidural needles, 30[degrees]versus 90[degrees]; (3) 18-gauge Tuohy, bevel perpendicular versus parallel to the dural long axis.

Results: With the 90[degrees] puncture, bevel parallel, the greatest leak occurred with a 17-gauge Hustead (516 +/- 319 ml/15 min), and the smallest leak occurred with a 20-gauge Tuohy (100 +/- 112 ml/15 min; P = 0.0018). A 20-gauge Tuohy puncture led to statistically significant reductions in leak (P value range, 0.0001-0.0024) compared with all needles except the Special Sprotte(R). With the 30[degrees]versus 90[degrees] angle, 30[degrees] punctures with an 18-gauge Tuohy produced nonstatistically significant leak reductions compared with the 18-gauge Tuohy at 90[degrees]. The puncture angle made no difference for the Special Sprotte(R). Nonsignificant reductions were found for the Special Sprotte(R) compared with the Tuohy. With the 18-gauge Tuohy bevel orientation, perpendicular orientation produced nonstatistically significant reductions in leak compared with parallel orientation.  相似文献   

13.
Immune response to intraocular injection of retinal S-antigen in adjuvant   总被引:1,自引:0,他引:1  
It has been proposed that the introduction of foreign material into the eye at the moment of a penetrating trauma provides an adjuvant effect which, coupled with the release of antigen, might be responsible for sensitizing the immune system to produce a contralateral sympathetic ophthalmia. We addressed that hypothesis by injecting S-antigen with complete Freund's adjuvant (CFA) into the anterior chamber (AC) of the eye of Lewis rats. The injection of an identical dose of antigen (30 g S-Ag in CFA in a total volume of 10 l) via the foodpad (FP) or under the conjunctiva (SC) could induce typical experimental autoimmune uveitis (EAU). By immunizing via the AC route, we could demonstrate a positive sensitization of the immune system, manifested by serum antibody production against S-Ag and by the presence of S-Ag-specific, responsive T-lymphocytes in the spleen. However, immunization via the AC route did not induce contralateral uveitis, and the animals did not produce a DTH skin response when challenged intradermally with S-Ag as they did after FP immunization. In the light of these results, we evaluated the possibility that a DTH suppressive response was elicited by intracameral (IC) injection as seen in anterior chamber-associated immune deviation (ACAID): we tested the effect of splenectomy and cyclophosphamide pretreatment before IC immunization and the effect of secondary footpad immunization as well as T-helper cell transfer after IC immunization. The results given by these approaches argue against the induction of suppressor cells by IC immunization. We believe that the absence of lymphatic drainage from the interior of the eye is probably responsible for the absence of EAU induction through the IC route and that extrusion of the antigen under the conjunctiva might be required for the activation of EAU effector cells.  相似文献   
14.
Seven flavonol 3- O-glycosides were isolated from the flowers of CALENDULA OFFICINALIS L. Their structures were elucidated as isorhamnetin 3- O-glucoside, rutinoside, neohesperidoside, 2 (G)-rhamnosylrutinoside, quercetin glucoside, neohesperidoside, and 2 (G)-rhamnosylrutinoside by paper and thin layer chromatography, UV, (13)C-NMR, and mass spectroscopy. The interglycosidic linkages of isorhamnetin 3- O-neohesperidoside, 2 (G)-rhamnosylrutinoside, quercetin 3- O-neohesperidoside and structural determination of quercetin 2 (G)-rhamnosylrutinoside are described for the first time in CALENDULA OFFICINALIS.  相似文献   
15.
Allotype- or idiotype-specific CD4+ T cells have been reported to recognize immunoglobulin (Ig) peptides presented by class II molecules. In contrast, few data are available concerning the generation of Ig peptide-specific CD8+ T cells. We have therefore investigated whether T-depleted spleen cells from Ig x light chain-expressing 129/Sv mice (129x+/+) could induce, in Cx knockout mice (129 x?/?), the generation of Ig constant x light chain region (Cx)-specific cytotoxic T lymphocytes (CTL). The determination of TCRβ chain expressed by nine CTL clones, together with the use of a library of overlapping peptides spanning the whole Cx sequence, show that the B cells from x+/+ mice are able to elicit in Cx knockout mice, the emergence of a diverse CTL repertoire that recognizes one single Cx peptide presented by the H-2Kb class I molecule. In addition, these data support the notion that B cells are able to process and present on their class I molecules, peptides generated from their own x light chains.  相似文献   
16.
Patients with renal failure represent a population at risk for hepatitis B, since only 50 to 60% of them develop protective humoral responses after vaccination. As this could be due to an altered regulation of cellular immune responses, the objectives of the present study were to evaluate the proliferative abilities of lymphocytes from patients with chronic renal failure after stimulation in vitro with a mitogen (pokeweed mitogen [PWM]) or HBsAg. In order to differentiate between the immunodeficiency associated with renal failure and that due to immunosuppression posttransplantation, the same subjects were tested before and 4 months after kidney transplantation. The lymphoproliferation assay used was performed by flow cytometry, which is based on sequential analysis of the cell cycle and which allows analysis of cytokine production. Serologically, the group of 36 patients tested comprised 22% nonresponders, 30% poor responders, and 48% responders. Lymphocyte growth was observed for all patients after stimulation with PWM, indicating that these cells had the capacity to proliferate in vitro. The level of lymphoproliferation in response to PWM was significantly reduced after transplantation, yet both before and after transplantation, all serologic nonresponders developed cellular responses to at least two vaccines. No correlation between humoral and cellular responses was shown. Proliferating cells were lymphocytes, which mostly secreted interleukin 4 (IL-4) and IL-10 for the three serologic groups. This study suggests that even when repeated vaccination fails to induce significant antibody levels in patients with renal failure, specific HBs cellular responses develop, and these may prove to be efficient in protecting these patients against hepatitis B.  相似文献   
17.
Hereditary pancreatitis (HP) is a rare inherited disorder, characterised by recurrent episodes of pancreatitis often beginning in early childhood. The mode of inheritance suggests an autosomal dominant trait with incomplete penetrance. The gene, or at least one of the genes, responsible for hereditary pancreatitis has been mapped to the long arm of chromosome 7 and a missense mutation, an arginine to histidine substitution at residue 117 in the trypsinogen cationic gene (try4) has been shown to segregate with the HP phenotype. The aim of this work was to investigate the molecular basis of hereditary pancreatitis. This study was performed on 14 HP families. The five exons of the trypsinogen cationic gene were studied using a specific gene amplification assay combined with denaturing gradient gel electrophoresis (DGGE). The present paper describes three novel mutations, namely K23R and N29I and a deletion -28delTCC in the promoter region. We also found a polymorphism in exon 4, D162D. In eight of these families we found a mutation which segregates with the disease. A segregation analysis using microsatellite markers carried out on the other families suggests genetic heterogeneity in at least one of them. Our findings confirm the implication of the cationic trypsinogen gene in HP and highlight allelic diversity associated with this phenotype. We also show that the pattern of inheritance of HP is probably complex and that other genes may be involved in this genetic disease.  相似文献   
18.
Congenital central hypoventilation syndrome (CCHS, Ondine's curse) is a rare disorder of the chemical control of breathing. It is frequently associated with a broad spectrum of dysautonomic symptoms, suggesting the involvement of genes widely expressed in the autonomic nervous system. In particular, the HASH-1-PHOX2A-PHOX2B developmental cascade was proposed as a candidate pathway because it controls the development of neurons with a definitive or transient noradrenergic phenotype, upstream from the RET receptor tyrosine kinase and tyrosine hydroxylase. We recently showed that PHOX2B is the major CCHS locus, whose mutation accounts for 60% of cases. We also studied the proneural HASH-1 gene and identified a heterozygous nucleotide substitution in three CCHS patients. To analyze the functional consequences of HASH-1 mutations, we developed an in vitro model of noradrenergic differentiation in neuronal progenitors derived from the mouse vagal neural crest, reproducing in vitro the HASH-PHOX-RET pathway. All HASH-1 mutant alleles impaired noradrenergic neuronal development, when overexpressed from adenoviral constructs. Thus, HASH-1 mutations may contribute to the CCHS phenotype in rare cases, consistent with the view that the abnormal chemical control of breathing observed in CCHS patients is due to the impairment of noradrenergic neurons during early steps of brainstem development.  相似文献   
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