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1.
Alexey V. Mazurov Dimitry V. Vinogradov Svetlana G. Khaspekova Anatoly V. Krushinsky Ludmila V. Gerdeva Sergei A. Vasiliev 《European journal of haematology》1996,57(1):38-41
Abstract: Patient B.G. is a 29-yr-old female with a lifelong bleeding disorder characterized clinically by a highly increased bleeding time, menorrhagias, long-lasting bleeding after cuts and tooth extractions and large post-traumatic haematomas. Her coagulation tests were within normal range, platelet count was 140,000–160,000 per μl, but platelet function was impaired as demonstrated by the absence of collagen-induced aggregation, although no abnormalities were detected in aggregation response to ADP and ristocetin. Morphologically her platelets were characterized by gigantic size – average profile area was about 2.5 times higher than that of control donors, and severe deficiency of α-granules – only 16% of their number in control donors. These features taken together indicated the diagnosis of grey platelet syndrome. As has been shown by quantitative immunoblotting, patient's platelets contained small amounts of α-granule membrane protein P-selectin – about 15% of that in control donors. The content of plasma membrane glycoproteins IIb–IIIa and Ib was not reduced, suggesting the specific deficiency of α-granule membrane protein. Thus, B.G. is the second patient described in the literature (see also Lages et al, J Clin Invest 1991: 87: 919–929) with combined deficiency of α-granules and P-selectin. 相似文献
2.
Tribulova N Knezl V Okruhlicova L Drimal J Lamosova D Slezak J Styk J 《Experimental physiology》2004,89(5):629-636
Hypokalaemia increases the risk for life-threatening arrhythmias; however, data about interaction with thyroid status are lacking. The aim of this study was to investigate vulnerability of l-thyroxine (T(4))-treated adult and old rats to low K(+)-induced ventricular fibrillation (VF) as well as the ability of the heart to recover sinus rhythm. The experiments were performed on isolated heart preparations using the heart of 4- and 20-month-old female Wistar rats without and with feeding with T(4) 50 microg (100 g day)(-1) over a period of 2 weeks. Perfusion of the isolated heart with oxygenated Krebs-Henseleit solution at constant pressure was followed by perfusion with K(+)-deficient solution until occurrence of VF (< 10 min). After 2 min of sustained VF, the heart was perfused with normal solution for 10 min, during which sinus rhythm was restored. ECG, left ventricular pressure (LVP) and coronary flow were continuously monitored. The results showed that compared with untreated rats, the onset of low K(+)-induced ventricular premature beats was delayed and their number was significantly decreased in both T(4)-treated groups. Nevertheless, VF occurred earlier in T(4)-treated than in non-treated adult rats (6.78 +/- 0.28 vs. 9.59 +/- 0.55 min, P < 0.05), whereas the difference was not significant in aged animals. Furthermore, sinus rhythm appeared earlier in old T(4)-treated rats compared with non-treated rats (7.18 +/- 0.57 vs. 8.94 +/- 0.64 min, P < 0.05), whereas in adult hearts it set in at practically the same time regardless of treatment. In conclusion, our results indicate that administration of a pharmacological dose of T(4) can increase the risk of low K(+)-induced VF in adult but not in old animals; in the latter it even facilitated restoration of sinus rhythm. Moreover, enhanced mechanical function was observed in both adult and old T(4)-treated hearts. 相似文献
3.
Ji-Su Li Shu-Ping Tong Ludmila Vitvitski Christian Trpo 《Journal of medical virology》1995,45(2):151-155
Hepatitis C virus (HCV) exhibits considerable sequence variability and circulates in the blood at extremely low levels. Current methods for detecting HCV RNA are based mostly on nested polymerase chain reaction (PCR), in which part of the first amplification product is reamplified in the second tube by an internal primer pair. A novel nested PCR method was developed in which the two successive amplification processes are carried out in the same tube with a single step of physical manipulation. Careful selection of highly conserved sequences of the 5′ noncoding region as primers enabled successful detection of all three major genotypes circulating in France, including the one with variation in this region. Retaining high sensitivity of the conventional nested PCR, the novel method reduced greatly the risk of carry-over contaminations. It was also cost- and time-saving. The one-step nested PCR method is especially suitable for routine diagnosis of HCV infection in clinical laboratories. © 1995 Wiley-Liss, Inc. 相似文献
4.
5.
Alison Severn Damo Xu Jacqueline Doyle Ludmila M. C. Leal Catherine A. O'Donnell Sara J. Brett David W. Moss Foo Y. Liew 《European journal of immunology》1993,23(7):1711-1714
Murine macrophages produce nitric oxide (NO) from L-arginine on stimulation with lipopolysaccharide (LPS), alone or with interferon-γ (IFN-γ). The effect of incubation of macrophages with low concentrations of LPS on NO synthesis on subsequent stimulation was investigated, using a murine macrophage cell line, J774, and peritoneal macrophages from CBA mice. Cells which had been incubated with LPS produced significantly lower amounts of NO, and expressed lower levels of NO synthase activity, following stimulation with IFN-γ and LPS, or with a high concentration of LPS. This effect was not reversed by tumor necrosis factor-α. The ability of CBA macrophages to kill the intracellular parasite Leishmania major was markedly reduced by pre-incubation with LPS. Reduced NO production by macrophages previously exposed to LPS is a manifestation of endotoxin tolerance, and may represent an important means of regulation of NO synthesis and thus a survival mechanism for intracellular parasites. 相似文献
6.
Notes on the large scale preparation and on the properties of anti-lymphocyte serum for use in mice 下载免费PDF全文
D. Thomas Betty Mosedale Ludmila Rahr H. B. G. Epps D. C. Edwards 《Clinical and experimental immunology》1970,7(5):769-779
Mouse spleen and thymus cells have been used in the preparation of horse anti-mouse anti-lymphocyte serum (HAMLS). The cells were used either separately or in a mixture and three types of immunization schedules were used, viz. two-pulse, extended and chronic.
Antisera of marked immunosuppressive activity, as measured by the ability to prolong the life of skin homografts in mice, were obtained using all three schedules, the median survival time being, at best, 27·5 days for the chronic schedule, 26·7 days for the two-pulse schedule and 25·8 days for the extended schedule. The two-pulse and the extended schedules produced non-toxic antisera in a relatively short period of time but were uneconomic in terms of antigen and horses. The chronic schedule was preferred but after 10 weeks the development of unwanted antibodies precluded the further useful immunization of the horses.
相似文献7.
Asthma medication use in pregnancy and fetal growth 总被引:3,自引:0,他引:3
Bakhireva LN Jones KL Schatz M Johnson D Chambers CD;Organization Of Teratology Information Services Research Group 《The Journal of allergy and clinical immunology》2005,116(3):503-509
BACKGROUND: Given the high prevalence of asthma in pregnancy, it is important to understand the relationship between asthma medications and fetal growth in the context of appropriate treatment. OBJECTIVE: This study examines the effect of inhaled corticosteroids, systemic corticosteroids, and beta(2)-agonists on fetal growth in 654 infants born to women with asthma compared with 303 infants born to controls without asthma. METHODS: Subjects for this prospective study were enrolled throughout North America between 1998 and 2003 and followed up by the Organization of Teratology Information Services. Incidence of small for gestational age (SGA) infants and mean birth size measures were compared among groups. RESULTS: Mean birth weight of full-term infants born to mothers who used systemic corticosteroids (3373 g) was lower than in the beta(2)-agonist group (3552 g) and controls without asthma (3540 g; P < .05) after adjustment for other risk factors. However, no differences in the incidence of SGA for weight were observed among groups. Adjusted mean birth length was slightly shorter in the systemic steroid group compared with controls (P=.02). Incidence of SGA for length and head circumference and mean head circumference did not vary among groups (P>.05). CONCLUSION: The treatment of asthma with systemic corticosteroids resulted in a deficit of about 200 g in birth weight compared with controls and exclusive beta(2)-agonist users and no increased incidence of SGA. These results suggest that asthma management with beta(2)-agonists and/or inhaled corticosteroids during pregnancy does not impair fetal growth, whereas systemic corticosteroids have a minimal effect which should be weighed against the necessity to control severe asthma. 相似文献
8.
Mixed epithelial and stromal tumors of the kidney. A report of 22 cases 总被引:16,自引:0,他引:16
Michal M Hes O Bisceglia M Simpson RH Spagnolo DV Parma A Boudova L Hora M Zachoval R Suster S 《Virchows Archiv : an international journal of pathology》2004,445(4):359-367
Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison. 相似文献
9.
Vodicka Pavel; Bastlova Tatiana; Vodickova Ludmila; Peterkova Katerina; Lambert Bo; Hemminki Kari 《Carcinogenesis》1995,16(7):1473-1481
Occupational exposure to styrene was studied in nine workersof a hand lamination plant in Bohemia. Personal dosimeters wereused to monitor the styrene workplace exposure, and the levelsof styrene in blood and mandelic acid in urine were measured.Blood samples were taken at four occasions during a 7 monthperiod to determine styrene-specific 06-guanine DNA adductsin lymphocytes and granulocytes, DNA strand breaks and hypoxanthineguanine phosphoribosyltransferase (HPRT) mutant frequency inT-lymphocytes. Seven administrative employees in the same factory(factory controls) and eight persons in a research laboratory(laboratory controls) were used as referents. DNA adduct levelsdetermined by the 32P-postlabelling method in lymphocytes oflamina-tors were remarkably constant and significantly higher(P < 0.0001) than in factory controls at all four samplingtimes. HPRT mutant frequencies (MF) measured by the T-cell cloningassay were higher in the laminators (17.5 x106, groupmean) than in the factory controls (15.7x106, group mean)at three of the four sampling times, but the differences werenot statistically significant. However, a statistically significant(P = 0.021) difference between MF in the laminators (18.0 x106,group mean) and laboratory controls (11.8 xl06, groupmean) was observed at sampling time 4 (the only sampling timewhen this latter group was studied). This result indicates thatstyrene exposure may induce gene mutation in T-cells in vivo.DNA strand breaks were studied by the Comet assayat the fourth sampling time. The laminators were found to havesignificantly higher levels of DNA strand breaks than the factorycontrols (P = 0.032 for tail length, TL; P = 0.007 for percentageof DNA in tail, T%; and P = 0.020 for tail moment, TM). A statisticallysignificant correlation was also found between the levels oflymphocyte DNA adducts and all three DNA strand break parameters(TL P = 0.046; T% P = 0.026 and TM P = 0.034). On the contrary,no significant correlations were found between DNA adduct levelsand the HPRT mutant frequencies or between the mutant frequenciesand DNA strand breaks. Taken together, these results add furthersupport to the genotoxic and possibly mutagenic effects of styreneexposure in vivo. However, no simple quantitative relationshipseems to exist between the levels of styrene-induced DNA damageand frequency of HPRT mutation in T-lymphocytes. 相似文献
10.