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11.
Cleaning a firearm can be a hazardous task even when the gun is not loaded. This is the first reported case of hand injury from the barrel bore cleaning brush. Early surgical exploration and washout of the wound is required as it often heavily contaminated with rust and grime. The cleaning agents used are also highly corrosive to tissue.  相似文献   
12.
Background : The results of management of seminoma of the testis at the Department of Radiation Oncology St Vincent's Hospital, Sydney were evaluated retrospectively to: (i) establish that outcomes were in keeping with published results from centres in Australia and overseas; (ii) assess the impact of chemotherapy on management; and (iii) to determine ‘best practice’ management protocols based on our results and a review of the relevant literature. Methods : (i) Assessment of treatment results for stage I and II seminoma of the testis treated by post-orchidectomy radiotherapy and/or chemotherapy at St Vincent's Hospital between 1979 and 1993; (ii) literature review of published data from Australian and overseas centres on the management of seminoma of the testis, and in particular the use of surveillance or chemotherapy either alone, at time of relapse or combined with radiotherapy; and (iii) development of recommendations for use as management protocols in our department. Results : Our data and a review of the literature suggest that post-orchidectomy radiotherapy with chemotherapy for relapse in stage I and IIA disease results in long-term cure rates approaching 100%. Treatment with chemotherapy either routinely or selectively or using a surveillance policy is unlikely to show any improvement in outcome and may be less cost-effective and/or produce increased morbidity and the risk of secondary leukaemia. For stage IIB disease (5–10 cm) the use of initial combination chemotherapy with or without subsequent radiotherapy did not appear to give better outcomes than initial radical radiotherapy alone, reserving chemotherapy or further radiotherapy for relapse. For bulkier stage IIB disease (> 10cm). the use of initial chemotherapy plus consolidation radiotherapy appeared to be an appropriate treatment. Conclusions : Management protocols for seminoma of the testis at St Vincent's Hospital, Sydney Department of Radiation Oncology currently are (i) stage I, IA and IIB (5–10 cm): post-orchidectomy radiotherapy alone with chemotherapy or further radiotherapy for relapse; and (ii) stage IIB (> 10 cm) disease: initial chemotherapy post-orchidectomy followed by radiotherapy to sites of initial disease involvement.  相似文献   
13.
Subclinical or latent cases of gluten-sensitive enteropathy (GSE) are difficult to diagnose, and serology-positive, histology-negative (minimal morphologic change) and serology-negative, histology-positive patients have been identified. Both, particularly the histology-negative group, require the correct diagnosis for proper management, especially because the concept of minimal histologic change GSE has escaped attention in standard textbooks. We assessed the numbers and distribution of intraepithelial T cells and their subsets with CD3, CD8, and CD4 immunostaining and examined for crypt hyperplasia with mitotic and Ki-67 proliferative indices with the aim of refining the criteria for the diagnosis of minimal change GSE. Duodenal biopsies from 46 clinically suspected cases of GSE tested for antigliadin, antiendomysium, and antitissue transglutaminase antibodies were divided into four groups: serology-positive, histology-positive (S+H+, n = 20); serology-positive, histology-negative (S+H-, n = 22), representing the minimal morphologic change group; serology-negative, histology-positive (S-H+, n = 4); and serology-negative, histology-negative (S-H-, n = 28), controls with histologically normal duodenal biopsies obtained for unrelated reasons. The numbers of CD3+ and CD8+ intraepithelial T cells (IETCs) were significantly higher in histology-positive biopsies with (mean, 40.3/100 and 39.3/100 enterocytes, respectively) and without positive serology (mean, 33.3/100 and 35/100 enterocytes, respectively) compared with all other groups (S+H-, mean, 26.5/100 and 24.3/100 enterocytes, respectively; S-H-, mean, 23.3/100 and 17.9/100 enterocytes, respectively). Values for Ki-67 index in crypt enterocytes were also significantly different between histology-positive and histology-negative groups (P = 0.000). The distribution of CD3+ and CD8+ IETCs was mostly even along the surface enterocytes in histology-positive cases compared with the controls, which showed an uneven distribution. The 2 parameters that significantly discriminated between minimal morphologic change GSE (S+H-) and controls (S-H-) were Ki-67 index (P = 0.007) and the distribution pattern of CD8+ IETCs (P = 0.049). CD4 IETC counts were generally low, with no significant difference between all groups. The few S-H+ cases seen most likely represented false-negative serology, because the assessed parameters of this group and S+H+ cases were indistinguishable.  相似文献   
14.
Oncogenesis is the consequence of a series of genetic alterations that allow unrestrained cellular growth, tissue invasion, and eventual metastases. Tumor-related genes can be classified into functional categories. Proto-oncogenes/oncogenes have a stimulatory role in cell growth, and the inactivation of cancer-suppressor genes/antioncogenes results in the loss of cell cycle regulation. More recently, three other groups of tumor-related genes have been recognized. They include the antiapoptosis genes which protect from programmed cell death, the antimetastasis genes, and multidrug resistance genes. Besides aiding in tumor diagnosis, the detection of such tumor-associated genes and their products allows the identification of individuals with an inherited predisposition to neoplastic growths, and the overexpression of many of these oncogene products has been shown to be a potential marker of tumor behavior and a predictor of treatment outcome and response. The ability to utilize DNA and RNA probes for nucleic acid hybridization and polymerase chain reaction procedures in cell and tissue preparations of solid tumors and lymphoid proliferations expands and complements the information provided by immunohistochemical techniques. These probes allow direct visualization and correlation of specific genes and their protein products with cytomorphologic features, and form a powerful addition to the armamentarium of the cytopathologist and surgical pathologist. © 1995 Wiley-Liss, Inc.  相似文献   
15.
Yim EK  Reano RM  Pang SW  Yee AF  Chen CS  Leong KW 《Biomaterials》2005,26(26):5405-5413
Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features.  相似文献   
16.
AIMS: Nodal expression of the carcinoembryonic antigen (CEA), cytokeratin 20 (CK20), and guanylyl cyclase C (GCC) genes was measured in tandem in patients with colorectal cancer (CRC) to assess whether there would be sufficient agreement between these markers in their ability to detect micrometastasis to qualify one of them as a universal marker, and whether frozen and paraffin wax embedded tissues would yield similar results. METHODS: One hundred and seventy five frozen lymph nodes (FT) and 158 formalin fixed, paraffin wax embedded lymph nodes (PET) from 28 CRC cases were analysed using gene specific quantitative real time polymerase chain reaction, carried out on the LightCycler system with SYBR Green chemistry. RESULTS: There was significant disparity in positive detection of the three biomarkers in FT versus PET, with notable agreement achieved only for CEA (66.6%) in FT versus PET in Dukes' B disease, and between CK20 and GCC (44.6%) in FT, also in Dukes' B disease. One patient with full concordance in all three tumour markers with both tissue types suffered a relapse and died within two years of follow up. CONCLUSIONS: There was considerable discordance in the positive detection of the three tumour markers in both tissue types (FT versus PET). This brings into question whether using a single tumour marker to detect micrometastasis in one tissue type (FT or PET) is adequately representative, and challenges the concept of universal markers for molecular CRC metastatic detection. Multiple tumour markers would predict more accurately the metastatic potential of Dukes' B CRCs.  相似文献   
17.
Galactosylated surface is an attractive substrate for hepatocyte culture because of the specific interaction between the galactose ligand and the asialoglycoprotein receptor on hepatocytes. In this study, we described a scheme to achieve high density of immobilized galactose ligands on polyethylene terephthalate (PET) surface by first surface-grafting polyacrylic acid on plasma-pretreated PET film under UV irradiation, followed by conjugation of a galactose derivative (1-O-(6'-aminohexyl)-D-galactopyranoside) to the grafted polyacrylic acid chains. A high galactose density of 513 nmol/cm(2) on the PET surface was used in this study to investigate the behavior of cultured hepatocyte. This engineered substrate showed high affinity to fluorescein isothiocyanate-lectin binding. Primary rat hepatocytes, when seeded at a density of 2 x 10(5) cells/cm(2), attached to the galactosylated PET substrate at a similar efficiency compared with collagen-coated substrate. The hepatocytes spontaneously formed aggregates 1 day after cell seeding and showed better maintenance of albumin secretion and urea synthesis functions than those cultured on collagen-coated surface.  相似文献   
18.
The distribution of a previously described repeated DNA sequence present as a 1.3-kb PstI fragment in the genome of the rice blast fungus Magnaporthe grisea was analysed by carrying out DNA fingerprint analysis of 36 isolates including rice, non-rice and laboratory strains. The analysis of various higher-molecular-weight PstI fragments with homology to the 1.3-kb repeat revealed that these may arise predominantly from transposon insertions or point mutations. Analysis of a 5.1-kb derivative revealed both a point mutation at a PstI site and an insertion of a putative transposable element which caused an increase in molecular weight from 1.3 to 5.1 kb. Another repeat element of 1.4 kb was identified and found to exist in association with the 1.3-kb repeat. Both 1.3- and 1.4-kb elements were found to be parts of MGR583 (Hamer et al. 1989), a LINE-like element. These elements were present in a high copy number in all the rice and a majority of non-rice pathogens indicating that MGR583 is not a host-specific sequence as reported earlier. Our results suggest that repeated DNA elements in M. grisea have amplified independently of one another and further indicate that different isolates of M. grisea may have evolved from several distinct lines of origin. Received: 12 April / 12 November 1996  相似文献   
19.
Our goal was to determine the cytotoxic activity of effector cells in lymph nodes with metastatic melanoma. Lymphocytes contained within tumor cells from metastatic lymph nodes of two patients were allowed to proliferate in recombinant IL-2 (rIL-2, 100-1,000 units/ml) after 14–21 days of culture. Each set of lymphocytes showed cytotoxicity against autologous melanoma (AM, mean 72%) at effector to target ratio of 201 and K562 cells (mean 60%) using 4-h chromium-51 release assay. Using unlabeled AM and K562, each AM could partially block the activity against K562, but K562 could not block the activity against AM. These activated lymphocytes underwentin vitro sensitization (IVS) with irradiated AM cells and rIL-2 at 2-week intervals. After repeated IVS over about 50 days, each patient's lymphocytes showed cytotoxicity against AM (mean 54%) but not K562 (mean 5%,P < 0.001). These results indicate that different cytotoxic effector cells were present in the early and late phase of lymphocyte tumor culture. Repeated IVS resulted in the selection of specific cytotoxic T lymphocytes. Cold target inhibition assay demonstrated that melanoma cells contained common and individual AM-associated antigen in addition to K562-associated antigens.This work was supported by Biomedical Research Support Grant of the University of Arizona (no. 2S07 RR05675-20), the Elsa U. Pardee Foundation Grant, partly by the Arizona Chronic Disease Research Commission and partly by CA23074 from the National Institutes of Health, Bethesda, 20892, U.S.A.Recipient of the American Cancer Society Clinical Oncology Career Award, 1987–90.  相似文献   
20.
Yin C  Liao K  Mao HQ  Leong KW  Zhuo RX  Chan V 《Biomaterials》2003,24(5):837-850
The specific recognition between asialoglycoprotein receptor and galactose ligand at cell-substrate interfaces has been shown to mediate hepatocyte adhesion and maintain liver specific functions of hepatocytes. Conventionally, the success of hepatocyte attachment on engineered tissue scaffold is inferred from the degree of two-dimensional cell spreading that is measured by transmitted light microscopy. However, the actual contact mechanics and adhesion strength of hepatocytes during two-dimensional cell spreading has not been elucidated due to lack of biophysical probe. In this study, a novel biophysical technique known as confocal reflectance interference contrast microscopy (C-RICM) in conjunction with phase contrast microscopy is utilized to probe the adhesion dynamics, contact mechanics and two-dimensional spreading kinetics of HepG2 cells on galactose immobilized and collagen gel coated substrates. C-RICM demonstrates that HepG2 cells form strong adhesion contacts with both galactose-immobilized surfaces and collagen gel coated substrates. Moreover, HepG2 cells maintain their compact shapes in the presence of asialoglycoprotein receptor-mediated recognition while they become exceedingly spread under integrin-mediated adhesion on collagen gel coated substrate. The initial rate of adhesion contact formation and the steady-state adhesion energy of HepG2 cell population are highest on substrate conjugated with galactose ligand via a longer spacer. The adhesion dynamics and final adhesion energy of HepG2 cells depends both on the type of ligand-receptor interaction and the length of spacer between the ligand and substrate. Most importantly, new biophysical insights into the initial hepatocyte attachment that are critical for hepatocyte culture are provided through the decomposition of two-dimensional spreading and adhesion contact formation on bio-functional substrates.  相似文献   
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