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271.
The purpose of this study was to examine the stability of adolescents' career interests using the Strong-Campbell Interest Inventory (SCII). Students at a Midwestern high school were administered the SCII twice over a three-year period, and comparisons were made on Occupational Themes and Basic Interests. Significant differences in mean scores were found by gender and parental occupation, and these differences were relatively stable. The findings are discussed in relation to previous research and Holland's theory, and the implications are addressed. 相似文献
272.
We report a unique case of tubular polyclonal immunoglobulin G (IgG) deposition disease (PIDD) superimposed on diabetic nephropathy in an 84-year-old man presenting with subacute renal failure and proteinuria. The deposits were located exclusively between the tubular epithelial cells and the tubular basement membranes (TBMs) and stained intensely with antisera to IgG heavy chain and both kappa and lambda light chains. Electron microscopy revealed large predominantly extracellular electron-dense deposits with a distinctive curvilinear substructure. The associated light microscopic findings of tubular simplification with features of acute tubular necrosis implicate this tubulopathy as the cause of the acute renal failure. This appears to represent a unique entity that does not fit into any previously described category of renal tubular immune complex or immunoglobulin deposition disease. 相似文献
273.
274.
BACKGROUND: Portal tract eosinophil infiltration and an increase in the blood eosinophil count (EOS) have been shown to be specific markers of liver allograft rejection. The graft eosinophil infiltration is associated with the local release of eosinophil cationic protein. Therefore, serum eosinophil cationic protein concentration (ECP) is a potential marker for acute allograft rejection. We investigated the chronological relationship among and diagnostic value of serial changes in EOS, ECP, and liver function tests (LFTs) following liver transplantation. METHODS: EOS, ECP, serum alpha-glutathione S-transferase concentration, and conventional LFTs were measured in serial samples collected over the first 3 postoperative months following 58 liver transplants. The diagnostic potential of each test, alone or in combination, was reviewed over the entire follow-up period. RESULTS: EOS and ECP increased at a median period of 3.5 and 4 days, respectively, before the diagnosis of acute rejection, and this increase was significantly earlier than the corresponding changes in LFTs (P<0.05). There was a significant correlation between the day of the first increase in EOS and alpha-glutathione S-transferase (rs=0.535; P=0.009) and EOS and alanine transaminase (rs=0.629; P=0.004). The optimum combination of tests for the diagnosis of acute rejection was an increase in both EOS and GST with a predictive efficiency of 84%. CONCLUSIONS: Increases in EOS and ECP are early indicators of acute liver allograft rejection and precede evidence of hepatocellular damage. However, an increase in ECP was also frequently associated with infection. Therefore, we recommend the regular monitoring of EOS in conjunction with routine LFTs after liver transplantation as an aid to the early diagnosis of acute rejection. 相似文献
275.
Forearm rotation affects grip strength. In a study with 40 volunteers, an overall decrease in grip strength was observed when the forearm rotated from pronation to supination. In males grip strength in pronation was significantly lower compared to the neutral and supinated position, with the wrist free as well as in an immobilized wrist position. In females this was only observed with a free wrist position, but with the wrist immobilized, the grip strength was higher in supination compared to neutral and pronation. 相似文献
276.
277.
Retinal pigment epithelium transplantation has been proposed as adjunctive treatment for age-related macular degeneration following surgical excision of choroidal neovascular membranes. The goal of this study was to develop a model to evaluate retinal pigment epithelium transplantation onto human Bruch's membrane in vitro. We investigated the ability of cultured fetal human retinal pigment epithelium to colonize human cadaver Bruch's membrane, determined the incubation time needed to form a monolayer and to exhibit apical microvilli and tight junctions, and assessed the production of basement membrane. Freshly enucleated (less than 48 hours old) human eyes were cut through the pars plana, and the anterior segment, vitreous, and retina were removed. The native retinal pigment epithelium was debrided with a surgical sponge. Bruch's membrane and choroid at the macula were trephined with a 7.0 mm diameter trephine and then incubated with 1/2 ml of Dulbecco's modified Eagle's medium +15% fetal calf serum+basic fibroblast growth factor (1 ng ml-1), and fetal human retinal pigment epithelium at a concentration of 242,000 cells ml-1. Specimens were incubated for 1, 4, 6, 8, 12, or 24 hours. The specimens were fixed in half strength Karnovsky's fixative, processed, and analysed with scanning and transmission electron microscopy. The retinal pigment epithelium covered the debrided macular specimens to different degrees at different incubation times. After 1 hour, the cells started to attach and flatten (median percent coverage: 78%). The extent of Bruch's membrane coverage by fetal retinal pigment epithelium varied greatly between specimens. After 4-6 hours, the cells covered the entire debrided surface in a monolayer (median percent coverage: 97.2% at 4 hours, 99.8% at 6 hours). Tight junctions were observed, and the cells had few apical microvilli. The lateral cell borders were obliquely oriented with respect to Bruch's membrane, and the nuclei were elongated, exhibited prominent nucleoli, and were oriented parallel to Bruch's membrane. After 6-8 hours, cells started to become hexagonal (median percent coverage at 8 hours: 99.97%). Cells attached to the inner collagenous layer tended to be flatter than cells attached to residual native basement membrane. At 12 and 24 hours, expression of hexagonal shape, tight junctions, and apical microvilli were observed more frequently (median percent coverage: 99.87% at 12 and 100% at 24 hours). No newly formed basement membrane was observed at these time points. In separate experiments comparing attachment in the presence and absence of native RPE basement membrane, the presence of native retinal pigment epithelial basement membrane promoted the early attachment of the cells and more rapid expression of normal morphology. This in vitro system provides a reproducible way to study the adherence of retinal pigment epithelium to normal and diseased human Bruch's membrane. 相似文献
278.
279.
AM Krieg T Wu R Weeratna SM Efler L Love-Homan L Yang AK Yi D Short HL Davis 《Canadian Metallurgical Quarterly》1998,95(21):12631-12636
Unmethylated CpG dinucleotides in particular base contexts (CpG-S motifs) are relatively common in bacterial DNA but are rare in vertebrate DNA. B cells and monocytes have the ability to detect such CpG-S motifs that trigger innate immune defenses with production of Th1-like cytokines. Despite comparable levels of unmethylated CpG dinucleotides, DNA from serotype 12 adenovirus is immune-stimulatory, but serotype 2 is nonstimulatory and can even inhibit activation by bacterial DNA. In type 12 genomes, the distribution of CpG-flanking bases is similar to that predicted by chance. However, in type 2 adenoviral DNA the immune stimulatory CpG-S motifs are outnumbered by a 15- to 30-fold excess of CpG dinucleotides in clusters of direct repeats or with a C on the 5' side or a G on the 3' side. Synthetic oligodeoxynucleotides containing these putative neutralizing (CpG-N) motifs block immune activation by CpG-S motifs in vitro and in vivo. Eliminating 52 of the 134 CpG-N motifs present in a DNA vaccine markedly enhanced its Th1-like function in vivo, which was increased further by the addition of CpG-S motifs. Thus, depending on the CpG motif, prokaryotic DNA can be either immune-stimulatory or neutralizing. These results have important implications for understanding microbial pathogenesis and molecular evolution and for the clinical development of DNA vaccines and gene therapy vectors. 相似文献
280.
Accidental and operative trauma are able to induce a systemic reaction of the organism characterized by fever, leukocytosis, catabolism, and an activation of the coagulation system. Interleukin-6 (IL-6) has been found to be an important mediator of this acute-phase response. In this study the influence of elective craniotomy on IL-6 plasma levels was evaluated. Blood samples were obtained from 20 patients undergoing elective craniotomy for vascular or tumorous diseases of the brain. IL-6 increased significantly (p < 0.05) from the pre-operative (0(0-5.4) pg/ml) to the intraoperative (180 min after beginning of surgery) time-point (10.6 (0-18.5) pg/ml). The maximum was reached on the first postoperative morning (13.9(4.3-45.0) pg/ml). Interleukin-10 (IL-10) is an anti-inflammatory cytokine which suppresses IL-6 synthesis in vitro in various cell lines. IL-10 plasma concentrations showed no alterations throughout the study period. Epinephrine plasma concentrations increased significantly from pre-operative values (15 (0-74) pg/ml) to the postoperative time-point (57(9-459) pg/ml). A 4.5-fold increase (p < 0.05) of norepinephrine plasma concentrations was found when comparing the data obtained 60 min after beginning of surgery with the data of the first postoperative morning. In monocytes, which are a major source of plasma IL-6, an elevation of intracellular cAMP stimulates the IL-6 synthesis. The postoperative maximum of IL-6 in plasma could be due to a release of catecholamines. In conclusion this study demonstrated an elevation of IL-6 plasma concentrations during and after elective craniotomy. Increased plasma catecholamine concentrations as well as a damage in the blood-brain barrier due to the surgical trauma with a spill-over of IL-6 from brain tissue into plasma could have contributed to this result. 相似文献