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1.
Modern data on selection and design of poxviruses, which are able to specifically lyse tumor cells of various origins and induce antitumor immunity and apoptosis of malignant cells, are presented in this review. Work is being carried out in several areas, including attenuation of viruses, insertion of immunomodulatory protein genes, and insertion of antitumor protein genes. Thymidine kinase and viral growth factor genes, inactivation of which results in an inability of the virus to replicate in nondividing cells and thus promotes an increase in selectivity for the tumor cells, make the greatest contribution in attenuation of the virus. Among the immunomodulatory proteins, interleukins 2 and 12 and granulocyte-macrophage colony-stimulating factor were the most promising in oncolytic viral therapy. An attempt to use the p53 protein gene, expressed by the Vaccinia virus, for targeted apoptosis of the tumor cells was described. Use of double and triple viral recombinants, which carry genes of differently directed effects, seems very promising. Encouraging results were obtained using the Vaccinia virus in cancer therapy by means of prodrugs and angiogenesis inhibitors. At present, two poxvirus strains are undergoing a third stage of clinical trials as antitumor drugs in the United States.  相似文献   
2.
Sitnicka  E; Lin  N; Priestley  GV; Fox  N; Broudy  VC; Wolf  NS; Kaushansky  K 《Blood》1996,87(12):4998-5005
In this study, we explored whether thrombopoietin (Tpo) has a direct in vitro effect on the proliferation and differentiation of long-term repopulating hematopoietic stem cells (LTR-HSC). We previously reported a cell separation method that uses the fluorescence-activated cell sorter selection of low Hoescht 33342/low Rhodamine 123 (low Ho/low Rh) fluorescence cell fractions that are highly enriched for LTR-HSC and can reconstitute lethally irradiated recipients with fewer than 20 cells. Low Ho/low Rh cells clone with high proliferative potential in vitro in the presence of stem cell factor (SCF) + interleukin-3 (IL-3) + IL-6 (90% to 100% HPP-CFC). Tpo alone did not induce proliferation of these low Ho/low Rh cells. However, in combination with SCF or IL-3, Tpo had several synergistic effects on cell proliferation. When Tpo was added to single growth factors (either SCF or IL-3 or the combination of both), the time required for the first cell division of low Ho/low Rh cells was significantly shortened and their cloning efficiency increased substantially. Moreover, the subsequent clonal expansion at the early time points of culture was significantly augmented by Tpo. Low Ho/low Rh cells, when assayed in agar directly after sorting, did not form megakaryocyte colonies in any growth condition tested. Several days of culture in the presence of multiple cytokines were required to obtain colony-forming units-megakaryocyte (CFU-Mk). In contrast, more differentiated, low Ho/high Rh cells, previously shown to contain short- term repopulating hematopoietic stem cells (STR-HSC), were able to form megakaryocyte colonies in agar when cultured in Tpo alone directly after sorting. These data establish that Tpo acts directly on primitive hematopoietic stem cells selected using the Ho/Rh method, but this effect is dependent on the presence of pluripotent cytokines. These cells subsequently differentiate into CFU-Mk, which are capable of responding to Tpo alone. Together with the results of previous reports of its effects on erythroid progenitors, these results suggest that the effects of Tpo on hematopoiesis are greater than initially anticipated.  相似文献   
3.
For the first time, the Canadian Hypertension Education Program has studied the evidence supporting blood pressure control in people requiring renal replacement therapy for end-stage kidney disease, including those on dialysis and with renal transplants. According to the Canadian Organ Replacement Registry’s 2008 annual report, there were an estimated 33,832 people with end-stage renal disease in Canada at the end of 2006, an increase of 69.7% since 1997. Of these, 20,465 were on dialysis and 13,367 were living with a functioning kidney transplant. Thus, it is becoming more likely that primary care practitioners will be helping to care for these complex patients. With the lack of large controlled clinical trials, the consensus recommendation based on interpretation of the existing literature is that blood pressure should be lowered to below 140/90 mmHg in hypertensive patients on renal replacement therapy and to below 130/80 mmHg for renal transplant patients with diabetes or chronic kidney disease.  相似文献   
4.
Aim: The aim of the student is to assess whether adolescents with type 1 diabetes mellitus (T1DM) in Italy differ from their healthy peers in regard to risky behaviour. Methods: Data were collected from 215 patients, aged 14 ± 2 years with a mean disease duration of 7 ± 5 years. The control group was comprised of 464 healthy adolescents recruited among high school students. Each patient completed an anonymous confidential questionnaire to determine the prevalence of sexual behaviour, alcohol and tobacco consumption, illicit drug use, and, among patients with diabetes and frequency of mismanagement related to diabetes care. Results: Compared with controls, subjects with diabetes showed a similar rate of sexual intercourse among males and lower rates among females (34.8% vs 35.5%, p NS and 29.4% vs 41.4%, p < 0.05, respectively). Males in the diabetes group reported a higher rate of tobacco use, whereas females showed similar or higher rates of use for every illicit drug studied. Among patients with diabetes, those who are engaged in risky behaviour showed a higher rate of treatment mismanagement (76% vs 34%, p < 0.01). Conclusion: Adolescents with T1DM are as likely as their healthy peers to engage in risky behaviour, indicating the potential benefit of anticipatory guidance concerning glycaemic control and increased risk of acute and chronic complications.  相似文献   
5.
Twenty-one oligosaccharides of human milk were quantified by high-performance anion-exchange chromatography. Milk samples were collected from 18 mothers during the first 3 mo of lactation. The data show that the highest amount of all oligosaccharides is present at day 4 postpartum (20 g l−1) and then decreases by about 20% at day 30 of lactation. The protective role played by these substances against different infectious agents, in different organs and systems of the breastfed baby, is emphasized.  相似文献   
6.
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.  相似文献   
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8.
The specificity of lethal infection was studied in noninbred white mice (age--15 to 20 and 25 to 30 days) infected intraperitoneally with the EP-2 strain of cowpox virus (CPV) in doses 10(5), 10(6) and 10(7) PFU. The virus caused the lethal infection in the 15-20-day mice; while the 25-30-day mice remained healthy and survived. Virologic, immunologic-and-histochemical and electron-microscopy examinations of the 15-20-day mice revealed a replication of the EP-2 strain in tissues bordering on the virus introduction area; there was no generalization of infection. The virus replicated first in the mesothelium cells, and after that, in fibroblasts as well as in the endothelial, fatty, adventicial, cross-striated and muscle cells and in myosatellites.  相似文献   
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The study was carried out at a number of industrial enterprises at risk of silicosis by means of the methodological approach based on the mathematical theory of image discrimination. It was shown that under the given conditions of dust exposure higher or lower probability of the development of silicosis and silicotuberculosis in an individual depended on the whole set of environment and endogenic factors, involving genetic predisposition to the disease as one of the leading factors. The impact of the above factors being similar irrespective of the type of the enterprise, their comparative contribution could be different. Thus reliable prediction of high probability of the disease development could be provided by means of the method of multifactorial analysis only as applied to specific conditions of the given enterprise. In spite of low prevalence of the genotype of silicosis- and silicotuberculosis-associated resistance, under the exposure to quartz dust, high probability of the disease development was predicted only in a number of cases if other individual symptoms were taken into account along the genotype. Therefore it became possible to identify the most susceptible persons at the stage of medical vocational selection.  相似文献   
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