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排序方式: 共有451条查询结果,搜索用时 31 毫秒
431.
Study of aneuploidy in normal and abnormal germ cells from semen of fertile and infertile men 总被引:4,自引:16,他引:4
Bernardini L; Borini A; Preti S; Conte N; Flamigni C; Capitanio GL; Venturini PL 《Human reproduction (Oxford, England)》1998,13(12):3406-3413
This study was undertaken with the aim of investigating the cytogenetic
constitution of normal as well as abnormal spermatozoa and immature germ
cells found in semen of normal men and infertile patients. A specific
protocol of double in-situ hybridization for chromosomes 1 and 17 based on
colorimetric detection of the hybridization signals (ISH) and brightfield
microscopy analysis of cellular morphology was applied. Also the influence
of paternal age on sperm aneuploidy was investigated. We found that, at
least in the age range analysed (28-54 years) and for semen of good quality
(total normal motile counts above 10 x 10(6)) (n = 17), paternal age has no
influence on baseline rates of sperm aneuploidy. However, with decreasing
semen quality (total normal motile sperm counts below 5 x 10(6)) (n = 6)
significantly higher rates of sperm aneuploidy for autosomes 1 and 17 were
scored (0.8 versus 1.43%) (P < 0.001). Regardless of the type of semen
analysed, a number of morphologically abnormal spermatozoa were found to be
hyperhaploid or diploid in a high percentage of cases (20 and 10%
respectively). The same was found for immature germ cells (aneuploidy rate
of 18%). We conclude that in infertile men with poor quality semen a direct
relationship may exist between the impairment of the spermatogenesis
process (as reflected by an increased production of morphologically and
cytogenetically abnormal germ cells) and rates of baseline aneuploidy
occurring in normal spermatozoa. Infertile couples undergoing assisted
reproduction treatment need to be counselled about the risk of using
spermatozoa which may carry higher rates of non- disjunction for different
chromosomes. While sperm hyper- or hypohaploidy for some chromosomes (X,Y)
implies counselling couples about the risk of abnormal phenotype in their
offspring, most autosomal sperm aneuploidies probably translate only into
lower rates of embryo fertilization and survival.
相似文献
432.
Kuper HH; van Leeuwen MA; van Riel PL; Prevoo ML; Houtman PM; Lolkema WF; van Rijswijk MH 《Rheumatology (Oxford, England)》1997,36(8):855-860
An assessment of the onset of radiographic damage in the large joints (hip,
knees, shoulders, elbows, ankles and tarsus) in patients with early
rheumatoid arthritis, and the relationship of the progression of large
joint damage with joint damage in hands and feet, with physical disability,
and with cumulative disease activity, was performed in a prospective 6 yr
follow-up study. Large joint damage appeared to be an early phenomenon with
20% of the patients having some damage in at least one large joint within 1
yr, and 50% of the patients within 6 yr after disease onset. Radiographic
damage in large joints was significantly related to the damage in hands and
feet, the physical disability index, and the cumulative disease activity.
The initial disease activity at study entry was the only prognostic factor
that reached significance.
相似文献
433.
Antin JH; Smith BR; Ewenstein BM; Arceci RJ; Lipton JM; Page PL; Rappeport JM 《Blood》1986,67(1):160-163
We prospectively documented the development of a fatal, secondarily acquired severe immunodeficiency in a 19-year-old man who underwent uncomplicated bone marrow transplantation. He had no graft v host disease (GVHD) and had normal recovery of his immune system as determined by lymphocyte phenotyping, mitogenic responses of his peripheral blood lymphocytes, and his ability to secrete immunoglobulin. This alteration in immunity was associated with the acquisition of antibody to HTLV-III. His only risk factor for the development of HTLV-III infection was the transfusions he had received during the transplant and recovery period. Two of his 54 transfusions were from an asymptomatic individual at high risk for acquired immunodeficiency syndrome (AIDS), who was subsequently found to be seropositive for anti-HTLV-III and from whom HTLV-III was isolated. The loss of immunocompetence in patients without chronic GVHD disease is unusual, and our data support the view that this patient's immunodeficiency was due to HTLV-III. When bone marrow transplant recipients without chronic GVHD develop late opportunistic infections, consideration should be given to transfusion-associated AIDS. 相似文献
434.
Human platelets secrete chemotactic activity for eosinophils 总被引:2,自引:1,他引:2
Thrombin-stimulated platelets liberate factors that induce chemotaxis of eosinophils and raise their cytosolic Ca2+ content ([Ca2+]i). The sources of this activity are the dense- and alpha-granules because inhibition of prostaglandin endoperoxide/thromboxane A2 formation and the platelet-activating factor receptor-antagonist WEB 2086 have no effect. Platelets from patients with Storage-Pool Deficiency show about 60% of the normal chemotactic activity with little effect on [Ca2+]i, whereas completely degranulated platelets fail to affect eosinophils. In concentrations secreted by the platelets, adenosine diphosphate (ADP), and platelet factor 4 have no effect, whereas adenosine triphosphate (ATP) induces a strong chemotactic response and increases [Ca2+]i. However, apart from ATP other modulating factors must be involved as platelet releasates induce more chemotaxis than ATP alone. Thus, platelets secrete factors that activate eosinophils and may contribute to inflammatory and allergic processes. 相似文献
435.
Live Newcastle disease virus (NDV) was used to investigate the in vitro effects of a viral infection on phagocytosis, chemiluminescence generation, superoxide production, oxygen consumption, NADPH-oxidase activity, and intracellular killing of bacteria by Ficoll-Hypaque separated human neutrophils. Phagocytosis of oil red O particles by NDV- treated PMN was inhibited by 50%. Chemiluminescence by PMN was inhibited 79% after zymosan stimulation and 86% after tetradeconyl phorbol acetate stimulation. Superoxide generation was inhibited by 68%. Oxygen consumption was inhibited in the presence of NDV by 37% after stimulation with phorbol myristate acetate, while membrane- associated NADPH-enzyme activity was decreased by 19%. The percent of surviving intracellular S. aureus was significantly elevated in NDV- treated PMN after 60 and 120 min of incubation. Purified bacterial neuraminidase markedly suppressed chemiluminescence, while neuraminic acid blocked the effects of the virus. These observations suggest that infections with myxoviruses may suppress a number of vital neutrophil functions. It appears that the effects may be partly mediated by the interaction of viral neuraminidase with the external neutrophil membrane. 相似文献
436.
Nicholas JH Ngiam Benjamin YQ Tan Ching-Hui Sia Bernard PL Chan Gopinathan Anil Yang Cunli Staffan Holmin Tommy Anderssen Kian-Keong Poh Leonard LL Yeo Vijay K Sharma 《Interventional neuroradiology》2020,26(6):793
Background and aimBi-directional feedback mechanisms exist between the heart and brain, which have been implicated in heart failure. We postulate that aortic stenosis may alter cerebral haemodynamics and influence functional outcomes after endovascular thrombectomy for acute ischaemic stroke. We compared clinical characteristics, echocardiographic profile and outcomes in patients with or without aortic stenosis that underwent endovascular thrombectomy for large vessel occlusion acute ischaemic stroke.MethodsConsecutive acute ischaemic stroke patients with anterior and posterior circulation large vessel occlusion (internal carotid artery, middle cerebral artery and basilar artery) who underwent endovascular thrombectomy were studied. Patients were divided into those with significant aortic stenosis (aortic valve area <1.5 cm2) and without. Univariate and multivariate analyses were employed to compare and determine predictors of functional outcomes measured by modified Rankin scale at three months.ResultsWe identified 26 (8.5%) patients with significant aortic stenosis. These patients were older (median age 76 (interquartile range 68–84) vs. 67 (interquartile range 56–75) years, p = 0.001), but similar in terms of medical comorbidities and echocardiographic profile. Rates of successful recanalisation (73.1% vs. 78.0%), symptomatic intracranial haemorrhage (7.7% and 7.9%) and mortality (11.5% vs. 12.6%) were similar. Significant aortic stenosis was independently associated with poorer functional outcome (modified Rankin scale >2) at three months (adjusted odds ratio 2.7, 95% confidence interval 1.1–7.5, p = 0.048), after adjusting for age, door-to-puncture times, stroke severity and rates of successful recanalisation.ConclusionIn acute ischaemic stroke patients managed with endovascular thrombectomy, significant aortic stenosis is associated with poor functional outcome despite comparable recanalisation rates. Larger cohort studies are needed to explore this relationship further. 相似文献
437.
Thomas ED; Sanders JE; Flournoy N; Johnson FL; Buckner CD; Clift RA; Fefer A; Goodell BW; Storb R; Weiden PL 《Blood》1983,62(5):1139-1141
Twenty-two patients with acute lymphoblastic leukemia in second or subsequent remission and 26 with acute lymphoblastic leukemia in relapse were given cyclophosphamide (60 mg/kg on each of 2 days), total body irradiation (920 rad), and marrow transplants from HLA-identical siblings. With a minimum follow-up of more than 5 yr, an actuarial analysis shows a survival and apparent cure of 27% of the patients transplanted in remission and 15% of the patients transplanted in relapse. 相似文献
438.
2-Aminoethylisothiouronium bromide (AET) increases the sensitivity of blood cells to complement-mediated immune lysis. We compared the sensitivities of untreated or AET-treated platelets to immune lysis induced by different types of platelet antibody in the 51Cr platelet lysis test. AET platelets were 8-16 times more sensitive to autoantibody and alloantibody, but 8-16 times less sensitive to drug- dependent antibody. AET-platelets bound similar amounts of alloantibody but less drug-dependent antibody, and they lysed at higher complement dilutions than did untreated platelets. AET-platelets detected 10 of 25 autoantibodies, 9 of 9 alloantibodies, and 5 of 8 drug-dependent antibodies. Untreated platelets detected 1 of 25, 6 of 9, and 7 of 8 of these respective platelet antibodies. The use of AET-platelets in the 51Cr platelet lysis test increases its sensitivity for detecting non- drug-dependent platelet antibodies. AET-platelets resemble paroxysmal nocturnal hemoglobinuria (PNH) platelets in their enhanced sensitivity to complement-mediated lysis. They differ from PNH platelets in their insensitivity to immune lysis induced by drug-dependent antibodies and, in this respect, are similar to Bernard-Soulier syndrome platelets. 相似文献
439.
We report here a case of moderately severe hemolytic disease of the newborn (HDN) due to anti-Ata. The gravida 5 proposita was group A rr and previously was found to have anti-Ata and -D. At the 35-week mark of this pregnancy, her anti-Ata demonstrated a titer of 256, score 79. Fluid obtained by amniocentesis at 36 weeks showed an optical density at 450 nm of 0.08 (midzone). The baby was delivered at 38 weeks by cesarean section. The cord cells were group A rr with a 3+ direct antiglobulin test. The dichloromethane eluate of the infant's cells demonstrated anti-Ata specificity only. At birth, the infant's total bilirubin (TB) was 2.1 mg per dl and the hematocrit level (Hct) was 33.8 percent. Within 8 hours, the TB had risen to 3.8 mg per dl. Phototherapy was initiated at 7-1/2 hours and maintained for 40 hours. The infant's TB rose to a maximum level of 10.5 mg per dl 24 hours after phototherapy was discontinued. At discharge 4 days postpartum, the infant's TB had dropped to 9.2 mg per dl, and the Hct value was 38 percent. On a visit 7 days postpartum, the infant's TB level had fallen to 6.5 mg per dl and the hct value was 38 percent. Transfusions were not necessary. 相似文献
440.
Animal transfusion models were established to assess treatment programs for preventing or reversing platelet alloimmunization. Five control baboons given weekly transfusions of radiolabeled platelets from a single unrelated donor became immunized after an average of 2.4 +/- 2.1 transfusions. Similarly, 18 of 21 (86%) dogs given up to eight platelet transfusions from a single unrelated donor became immunized after an average of 2.3 +/- 1.7 transfusions. In six of seven baboons, prednisone or antithymocyte globulin alone or in combination effectively delayed platelet alloimmunization. In contrast, only two of 12 (17%) dogs given prednisone or antithymocyte serum (ATS) resisted alloimmunization. Neither splenectomy nor cyclophosphamide prevented alloimmunization in the baboon. In addition, attempts to reduce the immunogenicity of transfused platelets by inactivating the contaminating leukocytes with gamma radiation or by giving leukocyte-poor platelets were of no benefit in dogs. Reversal of platelet alloimmunization was achieved in two of three dogs treated with ATS and procarbazine hydrochloride. However, neither splenectomy, cyclophosphamide, ATS plus prednisone, nor vincristine sulfate produced any improvement. These studies show that the highly immunogenic nature of platelet transfusions in animals makes feasible the study of the prevention and reversal of platelet alloimmunization. 相似文献