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31.
R. Fidler A. V. Sokolov M. Sh. Verbitskii I. P. Papazov 《Bulletin of experimental biology and medicine》1988,106(6):1727-1729
Research Institute of Human Morphology, Academy of Medical Sciences of the USSR. Research Institute of Clinical Oncology, All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 12, pp. 693–695, December, 1988. 相似文献
32.
Neurobehavioural effects of occupational exposure to organic solvents among construction painters. 下载免费PDF全文
A cross sectional study of 101 construction painters was performed to investigate the relation between exposure to mixed organic solvents and changes in central nervous system function. Solvent exposure was estimated using questionnaire data to derive an exposure index (a measure of intensity of exposure) and to estimate the duration and frequency of exposure. Adverse effects on the central nervous system were assessed by self reported questionnaires and eight tests of a computer administered neurobehavioural evaluation system. Factor analysis of both measures of effect yielded factors both biologically plausible and in agreement with other empirical evidence. A consistent positive association was observed between most measures of exposure and the occurrence of neurotoxic symptoms, notably dizziness, nausea, fatigue, problems with arm strength, and feelings of getting "high" from chemicals at work. Associations with exposure were found with the neurobehavioural evaluation system tests of symbol digit substitution and digit span; however, no consistent pattern of effect on neurobehavioural function was observed. This pattern of the occurrence of neurotoxic symptoms without clear evidence of function deficit is consistent with the type 1 toxic central nervous system disorder as classified by the World Health Organisation. 相似文献
33.
Different growth pattern and biologic behavior of human renal cell carcinoma implanted into different organs of nude mice 总被引:7,自引:0,他引:7
This study was designed to determine the influence of implantation site on the growth of local "primary tumors" and metastatic behavior of human renal cell carcinoma (HRCC) cells. HRCC lines were established in vitro from a surgical specimen (SN12C) or from a liver metastasis produced in BALB/c nude mice by cells from the original specimen implanted into their kidney (SN12L1). Cultured HRCC cells of both lines were injected into the subcutis and the renal subcapsule (RSC) of nude mice. Tumor growth and metastatic behavior were monitored. In both cell lines, tumor cells injected into the RSC displayed faster growth and produced more systemic metastases than did cells injected sc. The kidney tumors were large, invasive, highly vascularized, nonencapsulated, and with minimal central necrosis. In contrast, the subcutaneous tumors were highly encapsulated, with peripheral vascularization and extensive necrosis that developed as early as 2 weeks after sc implantation. The SN12L1 cells were also implanted into nude mice by iv, ip, and intrasplenic injections. The most dramatic production of metastasis occurred after the tumor cells were injected into the kidney. These results indicate that the biologic behavior of this HRCC is influenced by the implantation site in nude mice. At least for the HRCC tested, the kidney is the natural organ for growth. Implantation into the RSC is advantageous for the study of the biology and therapy of HRCC in nude mice. 相似文献
34.
Lario Viljoen Virginia A. Bond Lindsey J. Reynolds Constance Mubekapi‐Musadaidzwa Dzunisani Baloyi Rhoda Ndubani Anne Stangl Janet Seeley Triantafyllos Pliakas Peter Bock Sarah Fidler Richard Hayes Helen Ayles James R. Hargreaves Graeme Hoddinott 《Sociology of health & illness》2021,43(1):167-185
Despite continued development of effective HIV treatment, expanded access to care and advances in prevention modalities, HIV‐related stigma persists. We examine how, in the context of a universal HIV‐testing and treatment trial in South Africa and Zambia, increased availability of HIV services influenced conceptualisations of HIV. Using qualitative data, we explore people’s stigma‐related experiences of living in ‘intervention’ and ‘control’ study communities. We conducted exploratory data analysis from a qualitative cohort of 150 households in 13 study communities, collected between 2016 and 2018. We found that increased availability of HIV‐testing services influenced conceptualisations of HIV as normative (non‐exceptional) and the visibility of people living with HIV (PLHIV) in household and community spaces impacted opportunities for stigma. There was a shift in community narratives towards individual responsibility to take up (assumingly) widely available service – for PLHIV to take care of their own health and to prevent onward transmission. Based on empirical data, we show that, despite a growing acceptance of HIV‐related testing services, anticipated stigma persists through the mechanism of shifting responsibilisation. To mitigate the responsibilisation of PLHIV, heath implementers need to adapt anti‐stigma messaging and especially focus on anticipated stigma. 相似文献
35.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
36.
Wilmanns C Fan D Obrian C Radinsky R Bucana C Tsan R Fidler I 《International journal of oncology》1993,3(3):413-422
The purpose of the study was to determine whether the organ environment can influence the response of colon cancer cells to chemotherapy. The highly metastatic human colon cancer cell line KM12L4, previously selected for production of liver metastases in nude mice, was injected into the cecal wall and into the spleen to produce liver metastases, and into the subcutis of nude mice. Doxorubicin (DOX) at 10 mg/kg or saline (control) was injected intravenously on days 7 and 16 after tumor cell injection. The in vivo response of tumors growing in the cecum, liver, and subcutaneous (s.c.) sites as well as the DOX sensitivity of cell lines established from liver and s.c. tumors were compared. Colon cancers growing s.c. were more sensitive to DOX than tumors growing in the cecal wall or liver of nude mice. The difference in response to DOX between s.c. tumors (sensitive) and liver tumors (resistant) was not due to selection of cell populations with different sensitivity to DOX, or differences in DOX distribution. PKC activity was lower in tumors of the liver and the cecum than in s.c. tumors. The expression of P-glycoprotein as determined by flow cytometric analysis of tumor cells harvested from lesions in different organs correlated inversely with their sensitivity to DOX. Increased levels of P-glycoprotein correlated with mdr-1, mdr-3 mRNA expression as determined by Northern analysis. Collectively, the data show that the organ environment influences the response of human colon carcinoma cells to DOX and recommend that animal models of this disease for experimental therapeutic studies employ orthotopic implantation of tumor cells. 相似文献
37.
0 引言 胰腺多房性潴留性囊肿极为罕见,我科收治1例,报道如下.1 病例报告 患者,男,29岁,因发现右上腹包块11d入院,缘于11d前无明显诱因感右上腹痛,仅局限于右上腹部,无肩背部放散痛,伴间歇性发热,体温最高达38.3℃,经抗炎,对症治疗无效.并逐渐可触及右上腹有一肿块,在当地医院行穿刺检查为脓血性液体.镜检发现炎性细胞,B超示:胆囊窝下方及右肾内侧及腹腔动脉,下腔静脉外前方可见异常区,大小约9.1cm×6.6cm×7.6cm,边界清楚,形态不规则,内呈蜂窝状,可见多个大小不等的液性暗区,CT示:右上腹部上腔静脉前方6.0cm×9.0cm肿块和周围组织粘… 相似文献
38.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition 相似文献
39.
Antigen presenting cell (APC) function is central to the activation of anti-viral cytotoxic T-cells and antibody production. In previous studies we have evaluated APC function in HIV-1 infected patients as the capacity to present peptide to a well defined panel of CD4 T-cell clones. We found that APC from HIV-1 infected patients were defective in the capacity to present peptide to CD4 T-cell clones. The APC defect uncovered by this method was present early in infection and worsened with increasing viral load, suggesting that it was an important determinant of progression and anti-viral efficacy. The CD4 T-cell clones were, however, found to vary in their susceptibility to the APC defect. CD4 T-cell clones that failed to respond to peptide presented by HIV + APC were 1000-fold more readily inhibited by anti-CD4 antibody than T-cell clones which consistently responded to APC from patients infected with HIV-1 (HIV + APC). An intermediate group of T-cell clones were also identified that only responded to peptide and HIV + APC from asymptomatic patients. These results suggested that the underlying mechanism for the APC defect was binding of T-cell CD4 by APC-associated gp120. In this paper we discuss the evidence to support this hypothesis. 相似文献
40.
Fan D Poste G Obrian C Seid C Ward N Earnest L Fidler I 《International journal of oncology》1992,1(7):735-742
A variety of resistance phenotypes to cytotoxic agents in bacteria, protozoa parasites and mammalian cells are mediated by evolutionarily conserved proteins of the mdr family. The finding that chloroquine resistance in the malarial parasite, Plasmodium falciparum, that is mediated by an mdr-1 gene product can be circumvented by tricyclic antidepressant drugs has stimulated the present study to assess whether this class of agents might also modulate the multidrug resistance (MDR) phenotype(s) in mammalian tumor cells. The possible chemosensitizing effects of nine antidepressant drugs have been tested against the UV-2237M murine fibrosarcoma line and its MDR variant. At nontoxic concentrations all nine antidepressants markedly enhanced the cytotoxicity of ADR against the parental cells but were much less effective against the MDR cells. The most active antidepressant, trazodone, also enhanced the cytotoxicities of vinblastine and vincristine, but not those of actinomycin D, mitomycin C, or 5-fluorouracil. The parental cells treated with trazodone exhibited an increased accumulation of intracellular ADR, but lacked detectable alterations in the expression and drug-binding activity of plasma membrane P-glycoprotein, and trazodone did not affect the activities of isolated protein kinase C and calmodulin. These data suggest that the antidepressant drug trazodone may be useful in the reversal of the intrinsic drug resistance of tumor cells that express low levels of P-glycoprotein. 相似文献