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1.
A combined one stage anterior and posterior approach was used to excise a giant cell tumor involving the second lumbar vertebra. The tumor involved the anterior and posterior elements of the vertebra. A wide excision was feasible with immediate stabilization using the Luque instrumentation posteriorly and fibular strut grafts supporting the vertebral bodies anteriorly. The followup period was 13 years. There is no recurrence, and the patient has no symptoms of disease, and the fibular grafts are fully incorporated.  相似文献   
2.
Thirty-four sheep were submitted to surgery substituting the native ACL with the central third of the patellar tendon, ten enter this study. The purpose was to find a possible relationship between tissue pO2 and healing processes considering also the biomechanical and histomorphological aspects of the grafts. Four of them were sacrificed under general anaesthesia after 6 months, and six after 1 year in order to perform tissue pO2 measurement and an analysis of microvessel density on specimens of the normal ACL and the graft. Our data showed higher pO2 values of the autografts after 6 months. After 1 year the data was comparable to those of native ACL. This was confirmed by a microvessel count of the histological specimens and the data was in relationship to biomechanical and histomorphological analysis. Tissue pO2 can be observed and recorded in "in vivo" ACL, and patellar tendon used as graft, with no injury to their integrity. The monitoring system might be considered as an experimental tool for indirect controls of the anterior cruciate substitutes.  相似文献   
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4.
A raw milk bacterial isolate, identified as Yersinia kristensenii was found to produce a bacteriocin which was inhibitory to Yersinia enterocolitica but not to other selected species of Yersinia or Gram-negative bacteria. Maximum production of bacteriocin was obtained when the organism was grown in shake culture at 28 degrees C. Mitomycin C at a concentration of 0.5 micrograms ml-1 induced bacteriocin production. The bacteriocin was partially purified and characterized by ammonium sulphate fractionation and gel filtration. The bacteriocin was completely inactivated when treated with proteolytic enzymes (trypsin and chymotrypsin). Bacteriocin activity was heat-resistant and it retained some of its activity after 5 min at boiling temperature. A total of 15 bacteriocin sensitive-suspected food isolates were further identified biochemically as Yersinia enterocolitica and a non-sensitive isolate was identified as Yersinia intermedia.  相似文献   
5.

Abstract  

Silica functionalized Mn(acac)3 was prepared and employed for the one-pot oxidative synthesis of 2-arylbenzimidazoles, 2-arylbenzothiazoles; and oxidation of benzoins to benzils under air atmosphere using water as the reaction medium. Environmentally friendly procedure, chemoselectivity and excellent yields are main advantages of this procedure. In all the cases, the catalyst was found to be highly active and selective; passes hot filtration test successfully; and could be recycled several times with a slight loss of activity.  相似文献   
6.

Background  

Poor growth of children in developing countries is a major public health problem associated with mortality, morbidity and developmental delay. We describe growth up to three years of age and investigate factors related to stunting (low height-for-age) at three years of age in a birth cohort from an urban slum.  相似文献   
7.
Arteriovenous fistula (AVF) dysfunction is a common problem in hemodialysis patients. After surgical revision for malfunction, we used AVFs early to avoid complications associated with central venous catheters. In this study, we report experience with surgical revisions of native AVFs with suspected arterial dysfunction as the cause of inadequate arterial inflow for dialysis. Exclusion criteria were presence of a central venous catheter as a hemodialysis access, and clinical or radiologic evidence of stenosis or thrombosis of the distal venous segment of the AVF. We prospectively studied 50 patients (mean age 60.2 ± 10.5 years, 25 men and 25 women) with 59 revisions. The patients were followed until change in the modality of dialysis, transplant, or death. The types of AVFs revised were left wrist radiocephalic in 27 patients (54%), left forearm radiocephalic in 10 (20%), right wrist radiocephalic in 6 (12%), left antecubital brachiocephalic in 3 (6%), right antecubital brachiocephalic in 2 (4%), and right forearm radiocephalic in 2 (4%). The causes of inadequate arterial flow were juxta‐anastomotic thrombosis in 20 patients (40%), inadequate arterial anastomotic flow in 16 (32%), inadequate anastomosis in 7 (14%), and juxta‐anastomotic venous stenosis in 7 (14%). The primary surgical revision techniques were proximal neo‐anastomosis using the semiarterialized vein in 43 patients (86%), thrombectomy and re‐anastomosis in 5 (10%), and resection and repair in 2 (4%). Technical success, defined as successful cannulation of the revised AVF for hemodialysis and avoidance of central venous catheter, was achieved in 44 of 50 patients (88%). Technical failure occurred 6 cases, the causes being inadequate arterial flow in 3 patients, failure to cannulate the veins in 2 patients, and steal syndrome in 1 patient. After primary revisions failed, 9 re‐revisions were done in 6 patients. The 1‐year, 2‐year, and 3‐year primary and overall patency rates were 76.2%, 67.6%, 65.0%, and 85.7%, 75.7%, 65.0%, respectively. In conclusion, surgical salvage of the AVF with inadequate arterial flow is an effective approach that can be performed as an outpatient procedure and allows early cannulation of the semi‐arterialized veins, thus avoiding the use of central venous catheters.  相似文献   
8.
Complexes of salicylic acid (Sal) and 1,10-phenanthroline (Phen) were synthesized coordinated with terbium ion (Tb3+) in crystalline phases. The structural characterizations of the lanthanide complex were made using FT-IR, NMR (1H and 13C) and XRD techniques. These measurements confirm the formation of Tb(Sal)3Phen complex structure. The thermal aspects of the complex were examined using DTA and TGA techniques. An enhancement in luminescence intensity of Tb3+ ion bands were observed in Tb(Sal)3Phen complex as compared to TbCl3 crystals on 355 nm laser excitation. Enhancement is reported due to the efficient energy transfer process from Sal to Tb3+ ions. This is also confirmed by the time resolved photoluminescence spectroscopy with increase in lifetime of Tb3+ ions due to encapsulation in Sal/Phen network. Our system in itself can be a deserving candidate for luminescent solar collector material when coupled with solar cells.  相似文献   
9.
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   
10.
Natural killer (NK) cells can kill target cells by either necrotic or apoptotic mechanisms. Using the 51Cr-release assay to measure necrotic death of target cells, neonatal NK cells had low NK activity (K562 targets) and high lymphokine-activated killer (LAK) activity (Daudi targets) compared with adult cells, as has been previously reported. Using a 125I-deoxyuridine (125I-UdR) release assay, cord cells were shown to also have higher apoptotic LAK activity against YAC-1 target cells. Interleukin-4 (IL-4) inhibited interleukin-2 (IL-2)-induced necrotic killing of target cells by adult effectors but had no such inhibitory effect on cord cells. In contrast, IL-4 inhibited both adult and cord LAK cytotoxicity of YAC-1 target cells by apoptotic mechanisms with higher suppression observed in cord cell preparations. Using a colorimetric substrate conversion assay, IL-2 induced higher, and IL-4 had a more significant suppressive effect on, cord cell granzyme B enzyme activity compared with adult cells, paralleling apoptosis cytotoxicity data. Co-culture of either adult or cord LAK cells with IL-4 had a similar inhibitory effect on granzyme B protein expression, as detected by Western blotting. In contrast, IL-4 did not inhibit perforin expression, thereby defining IL-4 as a cytokine that can differentially regulate the NK cell-mediated cytotoxicity processes of apoptosis and necrosis. The differential sensitivity of cord cells to cytokine regulation of cytotoxicity may also have implications for cord blood transplantations, as NK cells are known to function as an effector cell in both graft-versus-host disease and in the graft-versus-leukaemia phenomena.  相似文献   
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