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71.
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We investigated the effect of Lewis Lung carcinoma cells on the production of C3 by murine macrophages and examined the capacity of secreted C3 to opsonize Lewis Lung carcinoma cells. C3 released in culture from macrophages obtained from tumor-bearing C57Bl/6 mice as well as from normal macrophages exposed to Lewis Lung carcinoma cells in vitro was measured by hemolytic assays and by Western blot. We found that contact with tumor cells in vivo as well as in vitro enhanced the amount of C3 secreted by murine macrophages by a factor of 2-3. The inflammatory agent carrageenan caused only a small increase in the amount of secreted C3. On Western blots of concentrated macrophage supernatants, there was partial cleavage of secreted C3 which was, however, not more pronounced in the case of C3 from tumor-stimulated macrophages than from normal macrophages. Supernatants from normal as well as tumor-stimulated macrophages were capable of opsonizing Lewis Lung carcinoma cells as shown by their capacity to bind human erythrocyte in an immune adherence reaction. Pretreatment of the tumor cells with a protease inhibitor, PMSF, inhibited the capacity of the tumor cells to bind C3, suggesting that a tumor cell-associated protease might be involved in the binding of C3 to the tumor cell surface.  相似文献   
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Treatment of Gallstone Pancreatitis: Six-year Experience in a Single Center   总被引:21,自引:0,他引:21  
Acute pancreatitis (AP) is a complicated disease in 20% to 25% of cases and carries a mortality of 8% to 15%. Etiologically, the most frequent form is acute biliary pancreatitis. Treatment of such an entity is still controversial, but minimally invasive techniques undoubtedly play an important role. We retrospectively analyze our cases of AP observed from January 1992 to May 1998. Etiology was biliary in 95/125 (76%) cases. In 90 cases we evaluated the patient within a few hours of the onset of symptoms. According to the Ranson criteria, we observed a mild form in 74/90 (82.2%) cases and a severe form in 16/90 (17.8%) cases. Our standard policy was to perform urgent endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy followed by elective laparoscopic cholecystectomy. In particular clinical settings, other modalities of treatment were employed, such as percutaneous cholecystostomy and percutaneous drainage of fluid collections. Successful ERCP was performed in 86/90 cases (95.5%). The procedure was performed in an emergency setting (within 48 hours) in 62/90 cases (68.9%). Whenever the patient was a candidate for surgery, cholecystectomy was performed, laparoscopically in 67/90 cases (74.4%) and via laparotomy in 7/90 cases (7.8%). In only two cases was pancreatic necrosectomy necessary. Globally, we observed a low procedure-related morbidity (6.7%) and no mortality. In the setting of acute biliary pancreatitis, regardless of the severity of the attack, an urgent ERCP + endoscopic sphincterotomy followed by laparoscopic cholecystectomy is safe and could enable successful management of the patient. Associated morbidity and mortality were low. In addition, when indicated, it is possible to treat a great number of concomitant complications with percutaneous ultrasound-guided drainage.  相似文献   
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Aim: The aim of the present study was to compare the direct and indirect cytotoxicity of a porcine dried acellular dermal matrix (PDADM) versus a porcine hydrated acellular dermal matrix (PHADM) in vitro. Both are used for periodontal and peri-implant soft tissue regeneration. Materials and methods: Two standard direct cytotoxicity tests—namely, the Trypan exclusion method (TEM) and the reagent WST-1 test (4-3-[4-iodophenyl]-2-[4-nitrophenyl]-2H-[5-tetrazolio]-1,3-benzol-desulphonated)—were performed using human primary mesenchymal stem cells (HPMSCs) seeded directly onto a PDADM and PHADM after seven days. Two standard indirect cytotoxicity tests—namely, lactate dehydrogenase (LTT) and MTT (3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazoliumbromide)—were performed using HPMSCs cultivated in eluates from the matrices incubated for 0.16 h (10 min), 1 h, and 24 h in a serum-free cell culture medium. Results: The WST and the TEM tests revealed significantly lower direct cytotoxicity values of HPMSCs on the PHADM compared with the PDADM. The indirect cytotoxicity levels were low for both the PHADM and PDADM, peaking in short-term eluates and decreasing with longer incubation times. However, they were lower for the PHADM with a statistically significant difference (p < 0.005). Conclusions: The results of the current study demonstrated a different biologic behavior between the PHADM and the PDADM, with the hydrated form showing a lower direct and indirect cytotoxicity.  相似文献   
77.
The effect of mixtures of azole fungicides on development of postimplantation rat whole-embryos cultured in vitro has been tested. On the basis of bench mark dose (BMD) modeling of the in vitro effect in rat embryo, the potency of 7 azoles was determined and compared. Then, relative potency factors have been derived based on either the NOAEL or on the BMD curve. Alternatively, each compound was used as index compound (IC), and IC-equivalent concentrations have been calculated for each mixture. Expected effects of such IC-equivalent concentrations of the mixture were derived from the appropriate BMD curve. Test mixture includes the agrochemicals triadimefon and imazalil (MIX2) or triadimefon, imazalil, and the clinically used fluconazole (MIX3) at their previously determined no-effect concentration, corresponding to approximately a benchmark response of 5–10 %. Subsequently, we tested the effect of a mixture of the agrochemicals triadimefon, imazalil, triadimenol, cyproconazole, tebuconazole, and flusilazole (MIX6) at concentration levels derived from their established human acceptable daily intake. MIX6 was also added with fluconazole at concentration levels indicated as the minimum therapeutically effective plasmatic concentration (MIX7A) or ten times this level (MIX7B). Generally, the experimental response was higher than the estimated one, by a factor of 2–6. Our data suggest that it is in principle correct to assume that azoles act as teratogens via a common mode of action and therefore should be grouped together for risk assessment. The synergistic effect needs to be confirmed with more combinations of concentrations/compounds in vitro and with specific in vivo experiments.  相似文献   
78.
The outcome of operations performed in different institutions or by different surgeons can hardly be compared if the operative methods are not standardized. Six different vaginal hysterectomy methods were studied. The steps common in all of them were defined. These steps were analyzed for optimal performance and sequence during the operation. The resultant modified method was subjected to a prospective randomized study, which showed that the operation time and the need for pain drugs were reduced. This method was introduced to several departments in different countries. The optimization and standardization of surgical methods are expected not just to improve the postoperative outcome, but also to enable a comparison between different departments and surgeons.  相似文献   
79.
It is well-known that a soap film spanning a looped wire can have the topology of a Möbius strip and that deformations of the wire can induce a transformation to a two-sided film, but the process by which this transformation is achieved has remained unknown. Experimental studies presented here show that this process consists of a collapse of the film toward the boundary that produces a previously unrecognized finite-time twist singularity that changes the linking number of the film’s Plateau border and the centerline of the wire. We conjecture that it is a general feature of this type of transition that the singularity always occurs at the surface boundary. The change in linking number is shown to be a consequence of a viscous reconnection of the Plateau border at the moment of the singularity. High-speed imaging of the collapse dynamics of the film’s throat, similar to that of the central opening of a catenoid, reveals a crossover between two power laws. Far from the singularity, it is suggested that the collapse is controlled by dissipation within the fluid film surrounding the wire, whereas closer to the transition the power law has the classical form arising from a balance between air inertia and surface tension. Analytical and numerical studies of minimal surfaces and ruled surfaces are used to gain insight into the energetics underlying the transition and the twisted geometry in the neighborhood of the singularity. A number of challenging mathematical questions arising from these observations are posed.  相似文献   
80.
Low-grade inflammation is a common feature of chronic kidney disease (CKD) and persistent systemic inflammation is thought to be a strong predictor of cardiovascular events. Inflammation plays a role in determining the serum albumin levels in haemodialysis patients (HD) independently of the nutritional status. Increased cardiovascular mortality in CKD has been associated with the increased incidence of obesity in uremic patients. Ingenbleek suggested a prognostic inflammation and nutritional index (PINI), based on serum albumin, pre-albumin, C-reactive protein, and alpha1 acid glycoprotein, to identify and to follow up acutely ill patients at risk of major complications. The aims of the present study were: to verify the incidence of Normal Weight Obese (NWO) syndrome; to evaluate by PINI the effect of 8 weeks acetyl salicylic (100 mg/die) and atorvastatin (10 mg/die) combined treatment on chronic inflammation in 52 selected HD patients. Laboratory evaluation, anthropometric and body composition measurements were detected. At baseline the 56.25% of non-obese, the 84.21% of pre-obese-obese, and the 41.17% of NWO women showed PINI values >1 (normal status PINI<1). After the pharmacological treatment, high significant (P<0.001) reduction in lipid profile, an elevated increase of HDL levels, and a significant reduction of inflammatory markers were obtained. Firstly, our results showed that ASA and atorvastatin combined treatment was effective in reducing inflammatory status in HD patients independently of body composition: at the end of the study only 7.49% of the patients exhibited PINI>1. Further studies will be necessary to understand the causes of inflammation in non-responder patients.  相似文献   
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