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71.
The first stages of the pathway by which lymphocytes differentiate from hemopoietic stem cells were studied at a clonal level. When 211 interleukin 3 (IL-3)-induced blast colonies shown to be capable of differentiating into a variety of hemopoietic cells were individually transferred into wells containing a monolayer of stromal cells, growth in granulocyte, macrophage, megakaryocyte, or mast cell lineages was observed in 192 wells. In seven of these 192 wells, lymphoid cell growth also was seen. The lymphoid cells were proved to be B lymphocytes by phenotype and immunoglobulin gene rearrangement analyses and by demonstration of surface expression of IgM. The clonal origin of myeloid and B lymphocyte lineage cells was further confirmed by the generation of both myeloid and B lymphoid cells in the same well following FACS clone-sorting of IL-3 induced blast cells. These results provide in vitro evidence that cells of B lymphoid and myeloid lineage can originate clonally from single primitive hemopoietic stem cells.  相似文献   
72.
One hundred and seven smears demonstrating a low-grade squamous intraepithelial lesion (LSIL) were analyzed for features predicting subsequent biopsy confirmation. Twelve (29%) of 41 smears showing few LSIL cells were biopsy confirmed compared to 33 (60%) of 55 containing an intermediate number of LSIL cells and 9 (82%) of 11 displaying many LSIL cells (P < 0.002). Thirty-seven (47%) of 78 smears showing mainly condylomatous atypia (CA), 7 (54%) of 13 revealing predominantly cervical intraepithelial neoplasia 1 (CIN 1), and 10 (63%) of 16 displaying both CA and CIN 1 were histologically confirmed (N.S.). Biopsy confirmation was obtained in 35 (65%) of 54 women whose repeat smears obtained at colposcopy demonstrated SIL compared to four (15%) of 26 patients whose repeat smears were normal or contained atypical squamous cells of undetermined significance (P < 0.001). These results suggest that the number of diagnostic cells in an LSIL smear predicts biopsy confirmation and affirm the validity of combining CA and CIN 1 under the category of LSIL in the Bethesda System. © 1994 Wiley-Liss, Inc.  相似文献   
73.
Anisakis simplex, a relevant etiologic factor in acute urticaria   总被引:1,自引:0,他引:1  
Del Pozo MD, Audícana M, Diez JM, Muñoz D, Ansotegui IJ, Fernández E, García M, Etxenagusia M, Moneo I, Fernández de Corres L. Anisakis simplex , a relevant etiologic factor in acute urticaria.
Anisakis simplex , a parasite of fish and cephalopods, can induce IgE-mediated reactions. This study aimed to determine the etiologic role of A. simplex in patients affected by urlicaria/angioedema 'AE' or anaphylaxis. We studied 100 adult subjects suffering acute episodes of urticaria/AE, by anamnesis, prick tests with A. simplex and fish-mix extracts, and total and specific IgE to both A. simplex and cod. The following criteria of A. simplex allergy were considered: 1' urticaria/AE within 6 h after fish ingestion; 2' specific IgE to A. simplex; 3' positive prick test to A. simplex extract; 4' exclusion of other suspected causes. Double-blind, placebo-controlled food challenge was not carried out because ethical considerations forbid challenge with a parasite. Specific IgE to A. simplex '<0.7 kU/1' was found in 22 subjects, but only eight were diagnosed as having A. simplex allergy. Other allergens were involved in 37 patients, and 55 cases were considered idiopathic. Specific IgE to fish '<0.7 kU/1' was found in two patients, but only one was diagnosed as having fish allergy. We concluded that A. simplex is an important etiologic factor in acute urticaria. We suggest that it should be considered in cases of urticaria/AE or anaphylaxis, especially after fish ingestion.  相似文献   
74.
Two siblings with a partial duplication 16q, born to a woman with a balanced translocation (6;16), are described. The first infant died at 8 weeks of age; the second died at 4 months. Fifteen other cases of duplications involving 16q have been reported, all of them derived from a balanced parental translocation. The most frequent physical findings have included dysmorphic facies characterized by high forehead, prominent nose, antimongoloid slant, malformed ears, and micrognathia, as well as flexion contractures of the joints, deformity of the feet, and genital hypoplasia in the male. Anorectal, intestinal and cardiac malformations were less frequent findings. Most of the affected infants died at ages ranging from 8 days to 6 months. The few with longer survival (up to 6 years) had a shorter, more distal segment duplication of chromosome 16. Although intrauterine growth retardation and microcephaly were not always present at birth, most of the infants had postnatal growth failure. The phenotypic and clinical findings of the two infants in this report are compared with those of previously reported cases, from which there appears to be correlation of the length of the 16q duplication with clinical phenotype and survivals.  相似文献   
75.
Anandamide (N-arachidonoylethanolamine, AEA) is a major endocannabinoid, known to impair mouse pregnancy and embryo development and to induce apoptosis in blastocysts. Here we show that mouse blastocysts rapidly (within 30 min of culture) release a soluble compound, that increases by approximately 2.5-fold the activity of AEA hydrolase (fatty acid amide hydrolase, FAAH) present in the mouse uterus, without affecting FAAH gene expression at the translational level. This "FAAH activator" was produced by both trophoblast and inner cell mass cells, and its initial biochemical characterization showed that it was fully neutralized by adding lipase to the blastocyst-conditioned medium (BCM), and was potentiated by adding trypsin to BCM. Other proteases, phospholipases A(2), C or D, DNAse I or RNAse A were ineffective. BCM did not affect the AEA-synthesizing phospholipase D, the AEA-binding cannabinoid receptors, or the selective AEA membrane transporter in mouse uterus. The FAAH activator was absent in uterine fluid from pregnant mice and could not be identified with any factor known to be released by blastocysts. In fact, platelet-activating factor inhibited non-competitively FAAH in mouse uterus extracts, but not in intact uterine horns, whereas leukotriene B(4) or prostaglandins E(2) and F(2)alpha had no effect. Overall, it can be suggested that blastocysts may protect themselves against the noxious effects of uterine endocannabinoids by locally releasing a lipid able to cross the cell membranes and to activate FAAH. The precise molecular identity of this activator, the first ever reported for FAAH, remains to be elucidated.  相似文献   
76.
An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.  相似文献   
77.
Endometriotic tissue grows invasively. The plasminogen-activating system is suggested to participate in degradation of extracellular matrix (ECM) and modulation of cell adhesion and migration. We have previously demonstrated elevated levels of the fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor (PAI-1) in endometriotic tissue and endometrium from women with endometriosis. The aim of the present study was to localize the uPA, PAI-1 and urokinase plasminogen activator receptor (uPAR) mRNA in endometriotic tissue and in endometrium both from women with and without endometriosis. With in situ hybridization, we found that uPA mRNA seems to be up-regulated in endometriotic glands and endometrial stroma as well as PAI-1 mRNA in endometriotic and endometrial stroma from women with endometriosis. uPAR mRNA likewise appears to be up-regulated in both glands and stroma in endometriotic tissue and in endometrial glands from patients compared to endometrial glands and stroma from healthy women. These differences might be important for menstrual shedding and adherence of endometrial fragments to peritoneal lining in women developing endometriosis and for the invasive growth of endometriotic tissue.  相似文献   
78.
Regional cerebral blood flow after occlusion of the middle cerebral artery   总被引:3,自引:0,他引:3  
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
79.
通过开展以“合理用药”为核心的重点监控药品管理,促进合理用药水平提升。采取事后处方点评及处方前置审核,建立和完善重点监控药品管理方案,对不合理用药进行拦截、宣教、绩效处罚、限量采购、约谈等,实现了重点监控药品规范化管理。实践后,不合理医嘱减少,处方点评合格率提升,辅助用药种类减少。认为建立重点监控药品管理的相关制度及流程,对提升合理用药水平有一定促进作用。  相似文献   
80.
目的通过分析2018年吉林市重点职业病监测结果,为吉林市职业病防治工作提供必要参考。方法通过吉林市7家职业健康检查机构的职业病报告系统个案导出数据、职业健康检查系统导出数据,收集2018年接触煤尘(煤矽尘)、矽尘、苯、铅、噪声、石棉等6种职业病危害因素,对作业人员的职业健康检查数据进行汇总分析,评估职业健康风险。结果 2018年吉林市全年接触重点职业病危害因素劳动者中疑似职业病人检出率为0.14%,职业禁忌证检出率为0.26%。专项检查指标异常情况:矽尘所致肺功能异常比例为54.88%,煤尘(煤矽肺)所致肺功能异常比例为16.7%,苯所致专项指标异常者比例分别为白细胞异常率2.28%、中性粒细胞异常率2.20%、血小板异常率0.18%,接触噪声作业人员双耳高频平均听阈≥40 dB的比例为11.46%。结论噪声、矽尘、煤尘(煤矽尘)仍是吉林市主要的职业病危害因素,重点职业病仍是尘肺病和噪声聋,主要分布行业集中在采矿业和制造业,应作为吉林地区职业病防治工作的重点。  相似文献   
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