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1.
The precise relationship between epidural use and genital tract lacerations in normal childbirth is unclear. Data from a clinical trial on measures to lower genital tract trauma in vaginal birth were used for a secondary analysis. The goal was to assess whether epidurals affect the rate of spontaneous obstetric lacerations in normal vaginal births. Maternal characteristics and intrapartum variables were compared in women who did and did not use an epidural in labor, and also in those with and without any sutured lacerations following vaginal birth. Variables that were statistically different in both cases were entered into regression equations for simultaneous adjustment. Epidural use was not an independent predictor of sutured lacerations. Predictors of sutured lacerations included nulliparity, a prolonged second stage, being non-Hispanic white, and an infant birthweight greater than 4000 grams. Elements of midwifery management need further research.  相似文献   
2.
Autosomal-recessive osteopetrosis is a severe genetic disease caused by osteoclast failure. Approximately 50% of the patients harbor mutations of the ATP6i gene, encoding for the osteoclast-specific a3 subunit of V-ATPase. We found inactivating ATP6i mutations in four patients, and three of these were novel. Patients shared macrocephaly, growth retardation and optic nerve alteration, osteosclerotic and endobone patterns, and high alkaline phosphatase and parathyroid hormone levels. Bone biopsies revealed primary spongiosa lined with active osteoblasts and high numbers of tartrate-resistant acid phosphatase (TRAP)-positive, a3 subunit-negative, morphologically unremarkable osteoclasts, some of which located in shallow Howship lacunae. Scarce hematopoietic cells and abundant fibrous tissue containing TRAP-positive putative osteoclast precursors were noted. In vitro osteoclasts were a3-negative, morphologically normal, with prominent clear zones and actin rings, and TRAP activity more elevated than in control patients. Podosomes, alphaVbeta3 receptor, c-Src, and PYK2 were unremarkable. Consistent with the finding in the bone biopsies, these cells excavated pits faintly stained with toluidine blue, indicating inefficient bone resorption. Bone marrow transplantation was successful in all patients, and posttransplant osteoclasts showed rescue of a3 subunit immunoreactivity.  相似文献   
3.
The progressive reduction in p27(Kip1) (p27) protein immunohistochemical staining with increasing histological grading is a well-established finding occurring in breast cancer, and its role as diagnostic complement and prognostic marker has been thoroughly evaluated. To clarify whether this test may be applied to breast cytopathology, we performed p27 immunostaining on fresh fine-needle cytology (FNC) samples from 10 benign and 40 malignant breast lesions. On average, p27 immunostaining was significantly lower in carcinomas than in benign lesions (P < 0.005). In particular, among carcinomas, p27 immunostaining progressively reduced from well-to poorly differentiated lesions (G1 vs. G2, P < 0.05; G1 vs. G3, P < 0.001; G2 vs. G3; P < 0.001). A similar trend was noted in a subgroup of 20 matched FNCs and histological samples of breast carcinomas, when p27 immunostaining on FNCs was stratified according to the histological grading (G1 vs. G2, P = 0.18; G1 vs. G3, P < 0.05; G2 vs. G3, P < 0.05). In addition, p27 immunostaining on FNCs showed a good positive correlation with that on histology (Spearman R = 0.58; P < 0.01), with a diagnostic concordance between samples of 85%, by using the standard 50% positive cell cutoff. Taken in concert, our data suggest that p27 immunostaining is a reliable marker of tumor cell differentiation in breast cytopathology as well as in histopathology. Accordingly, staining FNCs for p27 may be an useful complement in addition to cytological grading in the preoperative assessment of breast cancer.  相似文献   
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The literature contains conflicting reports on the association of common variants of the interleukin (IL)-4 receptor alpha (IL4RA) gene with atopic asthma. The purpose of the present study was to investigate the linkage and association of several gene polymorphisms with atopic asthma in a large series of well-characterized individuals. Analysis of five polymorphisms (I50V, E375A, C406R, S478P and Q551R) of the IL4RA gene was performed in 823 individuals from 182 families with atopic asthmatic children from north-east Italy. The subjects were tested for clinical asthma, total serum IgE level, skin prick test positivity to common aeroallergens, and bronchial hyperresponsiveness to methacholine. The frequency of the polymorphisms was similar to that reported for other populations. The 375, 406, 478 and 551 polymorphisms were in linkage disequilibrium, as previously reported. No linkage or transmission disequilibrium was observed in the families between any mutation and any of the phenotypes investigated. No multipoint haplotype was associated with any phenotype. In conclusion, the IL4RA gene does not seem to play an important role in genetic predisposition to atopic asthma in the population tested.  相似文献   
6.
PROBLEM: Plasma interferon (IFN)-beta levels, lymphocyte responsiveness, and evaluation of the relationship between circulating antiviral activity (AA) and IFN-gamma production were studied in pregnant women and nonpregnant age-matched controls with the objective of elucidating the downregulation of IFN-gamma production in successful pregnancy. METHOD OF STUDY: In plasma and supernatants of peripheral blood mononuclear cell (PBMC) cultures, stimulated with staphylococcal enterotoxin A (SEA) superantigen, from 43 pregnant women with a history of normal pregnancy and 30 healthy nonpregnant age-matched controls, levels of AA were measured in a micromethod by inhibition of the cytopathic effect (CPE) caused by vesicular stomatitis virus (VSV) in the human amnionic cell line (WISH). RESULTS: Significantly higher plasma AA (60% was IFN-gamma and residual activity was acid-labile IFN-like) was present in pregnant women than controls. On the other hand, SEA-activated PBMCs from pregnant women produced significantly lower IFN-gamma levels than those of nonpregnant women. Furthermore, maternal plasma AA levels correlated negatively with IFN-gamma production by SEA-stimulated PBMCs. CONCLUSION: The hypothesis that successful pregnancy requires downregulation of IFN-gamma is only partially sustained, suggesting that the immunology of pregnancy is more complex and that murine and human pregnancy have different cytokine profiles.  相似文献   
7.
The engraftment potential of murine stem cells (HSC) is greatly reduced when these cells are expanded in vitro with stem cell factor and interleukin-3. We have evaluated if the addition of MIP-1 alpha or LIF to these cultures would protect the ability of murine wild type HSC to engraft the stem cell defective W/Wv recipient. In this transplantation model red and white blood cell reconstitution is assessed by hemoglobin electrophoresis and c-kit PCR genotyping, respectively. The results obtained indicate that both MIP-1 alpha and LIF protect, at least transiently, the HSC repopulating ability in vivo in spite of the modest expansion in the number of nucleated and progenitor cells observed.  相似文献   
8.
The small volume of placental/umbilical cord blood (PUCB) collectable restricts the use of these stem cells to pediatric transplantation. To extend the use of PUCB to adult recipients, many laboratories are investigating the feasibility of ex vivo PUCB expansion. The present study analyses the effects that PUCB banking cell manipulations (cell sedimentation, cryopreservation and thawing, mononuclear and CD34+ cell isolation) have on the number, viability and ex vivo expansion potential of PUCB cells. The results presented indicate the necessity of an open discussion on whether procedures used for handling the cells in PUCB banks can be extrapolated or not as such to the clinical use of ex vivo expanded PUCB.  相似文献   
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The vestibulo-ocular reflex (VOR) is the main retinal image stabilising mechanism during rapid head movement. When the VOR does not stabilise the world or target image on the retina, retinal image slip occurs generating an error signal that drives the VOR response to increase or decrease until image slip is minimised, i.e. VOR adaptation occurs. Visual target contrast affects the human smooth pursuit and optokinetic reflex responses. We sought to determine if contrast also affected VOR adaptation. We tested 12 normal subjects, each over 16 separate sessions. For sessions 1–14, the ambient light level (lx) during adaptation training was as follows: dark, 0.1, 0.2, 0.3, 0.5, 0.7, 1, 2, 8, 16, 32, 64, 128 and 255 lx (light level for a typical room). For sessions 15–16, the laser target power (related to brightness) was halved with ambient light at 0 and 0.1 lx. The adaptation training lasted 15 min and consisted of left/right active head impulses. The VOR gain was challenged to increment, starting at unity, by 0.1 every 90 s for rotations to the designated adapting side and fixed at unity towards the non-adapting side. We measured active and passive VOR gains before and after adaptation training. We found that for both the active and passive VOR, there was a significant increase in gain only towards the adapting side due to training at contrast level 1.5 k and above (2 lx and below). At contrast level 261 and below (16 lx and above), adaptation training resulted in no difference between adapting and non-adapting side gains. Our modelling suggests that a contrast threshold of ~ 1000, which is 60 times higher than that provided by typical room lighting, must be surpassed for robust active and passive VOR adaptation. Our findings suggest contrast is an important factor for adaptation, which has implication for rehabilitation programs.  相似文献   
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