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Migration and differentiation of hematopoietic stem cells were studied in autoimmune (NZB×NZW)F1 mice of different ages. Migration of stem cells was shown to be reduced in old (NZB×NZW)F1 mice. Irrespective of age, inhibition of differentiation of stem cells along the granuloid path of development was observed in (NZB×NZW)F1 mice. It is suggested that in (NZB×NZW)F1 mice there is either a defect of development of the T-lymphocyte subpopulation influencing differentiation of stem cells along the granuloid pathway or a genetic defect at the level of precursors of the granulocyte series (CFUC).Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 2, pp. 224–226, February, 1980.  相似文献   
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The aim of the study was to try thrombo ASS in combined therapy of patients with antiphospholipid syndrome (APS), to evaluate its efficacy in prevention of recurrent vascular defects. Thrombo ASS tablets (50-100 mg) were included in combined treatment of 45 patients with APS (6 males and 39 females, mean age 36.1 +/- 11.7 years, mean APS duration 10.2 +/- 9.0 years) and 8 patients with SLE (1 male and 7 females) matched for age. Antiphospholipin antibodies and clinical status were assessed before treatment and after the treatment within 9 months. It was found that addition of thrombo ASS to combined treatment of APS improves coagulation and microcirculation due to effective muscular blood flow, increases number of platelets in peripheral blood. Tablets covered with coating resistant to gastric juice reduce frequency of gastric side effects.  相似文献   
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Pulmonary hypertension with elevated pulmonary vascular resistance is a common cardiovascular complication associated with increased morbidity and mortality in preterm infants with chronic lung disease. Injury to the developing pulmonary circulation results in structural and functional abnormalities of the pulmonary vasculature. Animal studies have demonstrated that disruption of angiogenesis may contribute to the failure of normal alveolarisation in chronic lung disease. Levels of vascular endothelial growth factor in bronchoalveolar lavage fluid are lower in infants with chronic lung disease compared to preterm controls. Supplemental oxygen is commonly used to prevent and treat pulmonary hypertension, although optimal arterial oxygen saturation levels remain uncertain. Other vasodilators such as inhaled nitric oxide appear promising, but as yet have not been evaluated in the form of randomised controlled trials. Further studies are required to investigate the long-term effectiveness of pulmonary vasodilator therapy.  相似文献   
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Background:

There is paucity of information on the relationship of quality of life (QOL) in obsessive compulsive disorder (OCD) and dysthymic disorder (DD) with disability grade in India.

Aim:

To assess the relation of QOL with disability level in OCD and DD.

Materials and Methods:

This hospital based study was conducted in a medical institution in Davanagere, Karnataka, India. Data was collected by using Diagnostic and Statistical Manual IV Text Revision (DSM IV TR) criteria, WHO QOL BREF and IDEAS. Relationship between disability grade and QOL was assessed by independent sample t test.

Results:

Mild disabled OCD patients had a significantly better QOL in the Q1 domain i.e. perception on quality of life as compared to moderately disabled patients (P < 0.05), while in other domains of QOL, there was no statistically significant difference (P > 0.05). But, QOL score in physical domain showed significant difference across disability grades (56.00, SD = 6.89; 48.50, SD = 12.28) in DD, but not in other domains.

Conclusion:

Perception of QOL is better in those with mild disability in OCD, but in DD, physical domain of QOL score is more in mild disability compared to moderate disability.  相似文献   
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AIM:To study the relationship between N-ras gene mutation and p53 gene expression in the carcinogenesis and the development of human hepatocellular carcinomas (HCC).METHODS:The N-ras gene mutation and the p53 gene expression were analyzed in 29 cases of HCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemistry.RESULTS:Thirteen cases of HCCs were p53 positive (44.8%), which showed a rather high Cpercen-tage of p53 gene mutation in Guangxi. The aberrations at N-ras codon 2-37 were found in 79.31% of HCCs and 80.77% of adjacent non-tumorous liver tissues. More than 2 point mutations of N-ras gene were observed in 22 cases (75.86%). Twelve cases (41.37%) of HCCs showed both N-ras gene mutation and p53 gene expression.CONCLUSION:N-ras gene and p53 gene may be involved in the carcinogenesis and the development of HCC.That 38% of HCCs with N-ras gene mutation did not express p53 protein indicates that some other genes or factors may participate in the carcinogenesis and the development of HCC.  相似文献   
9.
Infectious complications after combustion represent the leading cause of lethal outcomes and attract an increasing attention of specialized services (anesthesiologists-resuscitators, combustiologists, infectionists, immunologists, clinical pharmacologists etc.). The increased incidence of the pyo-septic pathology in the whole world resulted first of all in the growing number of complications of burn disease in children. At the same time there appeared new pathological states which are thought to be outside the frame of traditional notions (e.g. the development of toxic shock syndrome). Many causes depending on the functional peculiarities of the children organism are responsible for the specific course of burn disease in children, the process itself having a number of peculiar features.  相似文献   
10.
PURPOSE: The premature chromosome condensation technique has been used to compare chromatin breakage and repair in noncycling V79 cells following high and low LET radiation. MATERIALS AND METHODS: Plateau-phase V79 cells were exposed to graded doses of low energy Ar ions (LET 1233 keV/microm) and X-rays. Cells were fused to mitotic V79 cells immediately after exposure to examine initial chromatin breakage or after various time intervals of post-irradiation incubation to investigate the kinetics of chromatin break rejoining as well as the fraction of unrejoined fragments. RESULTS AND CONCLUSIONS: For both radiation qualities an average initial number of about 2.4 excess PCC fragments per cell per Gy was found increasing linearly with dose. The distributions of PCC chromosomes plus excess fragments among cells followed Poisson statistics after X-ray irradiation, while an overdispersion of the frequencies was observed after Ar-irradiation indicating that a single particle traversal through a cell nucleus can produce multiple chromatin lesions. Moreover, for both radiation types the rejoining of excess fragments has been examined. Both data sets could be fitted well to first-order kinetics with a single component. Despite similar rates of rejoining cellular repair was noticeably less effective for Ar ions than for X-rays. While after 10 h of post-irradiation incubation 60% of Ar ion induced excess fragments remained unrejoined, only 14% of X-ray-induced lesions were not rejoined. Furthermore, comparison of the residual number of excess PCC fragments with recently published data on the yield of chromosome aberrations in first post-irradiation metaphases shows that for both radiation types more aberrations are detected in interphase than in metaphase cells. Yet, for comparable doses this difference is more pronounced for Ar ions indicating that scoring of high LET induced aberrations in metaphase cells might result in a significant underestimation of the produced damage.  相似文献   
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