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71.
72.
Pancreatic cancer is a leading cause of cancer mortality and the incidence of this disease is expected to continue increasing. While patients with pancreatic cancer have traditionally faced a dismal prognosis, over the past several years various advances in diagnosis and treatment have begun to positively impact this disease. Identification of effective combinations of existing chemotherapeutic agents, such as the FOLFIRINOX and the gemcitabine + nab-paclitaxel regimen, has improved survival for selected patients although concerns regarding their toxicity profiles remain. A better understanding of pancreatic carcinogenesis has identified several pre-malignant precursor lesions, such as pancreatic intraepithelial neoplasias, intraductal papillary mucinous neoplasms, and cystic neoplasms. Imaging technology has also evolved dramatically so as to allow early detection of these lesions and thereby facilitate earlier management. Surgery remains a cornerstone of treatment for patients with resectable pancreatic tumors, and advances in surgical technique have allowed patients to undergo resection with decreasing perioperative morbidity and mortality. Surgery has also become feasible in selected patients with borderline resectable tumors as a result of neoadjuvant therapy. Furthermore, pancreatectomy involving vascular reconstruction and pancreatectomy with minimally invasive techniques have demonstrated safety without significantly compromising oncologic outcomes. Lastly, a deeper understanding of molecular aberrations contributing to the development of pancreatic cancer shows promise for future development of more targeted and safe therapeutic agents.  相似文献   
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During development inhibitor of DNA-bind-2 (Id2) regulates proliferation and differentiation. Id2 expression has been detected in cancer cells, yet its cellular function and validity as a therapeutic target remains largely unknown. Immunohistochemical analysis of colorectal cancer (CRC) specimens revealed that Id2 was undetectable in normal colonic mucosa, but occurs in 40% of primary tumors and in most CRC liver metastases (P<0.0001). Additionally, Id2 was expressed in all CRC cell lines assayed. CRC cells with reduced Id2 expression demonstrated reduced proliferation. Analysis of CRC cell cycle regulatory proteins showed that reducing Id2 levels reduces cyclin D1 levels and increased p21 levels. Reduction of Id2 expression also enhanced tumor cell apoptosis, increasing levels of the pro-apoptotic protein Bim/Bod, and cleavage of caspase-7 and poly (ADP-ribose) polymerase. In vivo studies show tumors derived from cells with decreased Id2 levels formed smaller tumors with fewer metastases compared with tumors with normal levels (P<0.05). Furthermore, intraperitoneal administration of Id2 small interfering RNA (siRNA) conjugated with the neutral liposome 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine decreased tumor burden in mice compared with control treatment (P=0.006). We conclude that Id2 is upregulated in CRC, and is important in promoting cell survival. In vivo targeting of Id2 by siRNA establishes that it is a valid therapeutic target where its expression occurs.  相似文献   
75.
硬肝复康防治肝硬化的初步实验研究   总被引:1,自引:0,他引:1  
目的 :研究复方中药硬肝复康对小鼠实验性肝纤维化的防治作用。方法 :单次或多次给予实验小鼠CCl4 油剂 ,分别造成急性肝损伤和肝纤维化 ;给小鼠静脉注射BCG和LPS造成免疫性肝损伤。检测各组实验小鼠血清ALT、AST、ALP ,并取肝纤维化小鼠肝脏做病理学检查。结果 :CCl4 急性肝损伤实验中 ,硬肝复康 (2g/(kg·d) )组小鼠ALT、ALP( (6153±3491)IU/L、(202±24)IU/L)低于对照组 ( (9275±2744)IU/L、(421±67)IU/L) (P<0 05) ;免疫性肝损伤实验中 ,硬肝复康组ALT、AST( (36 3±13 0)IU/L、(164 4±17 2)IU/L)显著低于对照组 ( (83 2±52 6)IU/L、(235 5±73 4)IU/L) (P<0 01) ;实验性肝纤维化实验中 ,硬肝复康组ALT、ALP( (1100±342)IU/L、(166±54)IU/L)显著低于对照组 ( (1638±336)IU/L、(328±128)IU/L) (P<0 01)。病理检查显示 ,硬肝复康组肝脏纤维化程度明显较轻。结论 :硬肝复康对慢性肝损伤和肝纤维化具有较好防治作用。  相似文献   
76.
Forty-nine patients among 360 who received renal transplants under cyclosporine (CsA)/prednisone (Pred) immunosuppression required alteration of the immunosuppressive regimen because of intractable nephrotoxicity. Twenty-five patients, converted totally to azathioprine (Aza)/Pred, suffered intractable nephrotoxicity with no associated evidence suggesting ongoing rejection. The results with Aza/Pred conversion were disappointing because of an unacceptably high incidence of rejection and allograft loss. Twenty-four patients with intractable CsA nephrotoxicity were, therefore, treated using an alternative approach combining Aza with aggressive CsA dose reduction, and continued Pred therapy. All patients tolerated initiation of Aza without complication; allograft rejection was not common. Renal function improved for 23 of the 24 (96%) CsA/Aza/Pred patients with mean serum creatinine levels falling from 3.5 +/- 0.5 mg/dL to 2.2 +/- 0.4 mg/dL after a mean follow-up of 14 months (P less than .001). Among 18 patients observed at least 12 months, seven (39%) enjoyed serum creatinine values less than or equal to 2 mg/dL. Nine CsA/Aza/Pred-treated patients (37.5%) required hospitalization because of infectious complications, all of which resolved with temporary reduction of immunosuppression and specific antimicrobial therapy when indicated. One patient sustained acute allograft rejection as a result of patient noncompliance, and one patient on a seemingly appropriate CsA/Aza/Pred dose responded initially to steroid pulse antirejection therapy; however, renal function again worsened. Two patients developed progressive renal dysfunction due to chronic rejection, and returned to dialysis 13 and 17 months, respectively, following initiation of CsA/Aza/Pred. Overall, the actuarial graft survival for CsA/Aza/Pred-treated patients was 100% at 1 year, and 84% at 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
In order to assess the impact of demographic factors on serum levels of cyclosporine (CsA) estimated by radioimmunoassay (RIA) in renal allograft recipients, 493 pharmacokinetic studies were performed in 212 patients. Neither the presence of diabetes mellitus nor the CsA dosing frequency affected the measured pharmacokinetic parameters. Age over 45 years led to slower CsA clearance with resultant increase in maximum serum concentration (Cmax) per administered milligram, and increased volume of distribution. Female patients showed more rapid drug clearance, but greater volume of distribution. Concomitant hepatic impairment reduced drug clearance, increasing the area under the curve (AUC) per administered milligram of drug, and the Cmax. Patients treated with a rapid steroid taper showed a shorter half-life and lower Cmax than those receiving a slow steroid taper. Nephrotoxicity was associated with increased AUC per administered mg, while patients with acute tubular necrosis requiring dialysis showed poorer drug absorption, lower Cmax, and longer time to peak. The only effect of cimetidine administration was a slightly shortened time to peak. Serial analyses posttransplant in 17 patients suggested a tendency toward improved drug absorption with no effect on other parameters. These studies demonstrating the significant impact of demographic factors thus afford a basis on which to predict the trend of anticipated CsA levels as measured by RIA in renal allograft recipients.  相似文献   
78.
The PREP system of nursing interventions, designed to increase preparedness (PR), enrichment (E), and predictability (P) in families providing care to older people, was pilot tested for acceptability and preliminary effectiveness. Eleven family units were assigned to the PREP group and 11 to a standard home health control group. The PREP group scored approximately one SD higher than the control group (p <.05) on the Care Effectiveness Scale, indicating greater preparedness, enrichment, and predictability. Further, on a rating of overall usefulness, the PREP group rated their assistance from PREP nurses (M = 9.75) as significantly higher (p <.01) than the control group rated assistance from the home health nurse or physical therapist (M = 6.57). Although not statistically significant, mean hospital costs for the PREP group ($2,775) were lower than for the control group ($6,929). Results provided support for a full intervention trial. ©1995 John Wiley & Sons, Inc.  相似文献   
79.
OBJECTIVES: to investigate the results of revision of recurrent stenoses after superficial femoral artery (SFA) remote endarterectomy. DESIGN: prospective, non-open, study. MATERIALS: eighty-eight consecutive patients with long segmental SFA occlusive disease underwent 101 remote end-arterectomy procedures. All patients had chronic lower extremity ischaemia necessitating surgical intervention. METHODS: clinical, haemodynamic, and duplex examinations were performed postoperatively at regular intervals, identifying 46 recurrent stenosed (PSV ratio >2.5) limbs, which formed the cohort for this study. The median follow-up was 25 months. Secondary revision was performed in 23 limbs, based on recurrent symptoms and individual preference of the attending vascular surgeon. Cumulative primary and primary assisted-patency rates were compared using the log-rank test of significance. RESULTS: univariate analysis did not show any significant differences for other demographic and lesion characteristics apart from recurrent symptoms (all revised). Multivariate analysis revealed that revision "adjusted for time-of-onset" predicted reocclusion (p=0.007; HR 0. 21; 95% CI 0.06, 0.66). Among subjects in whom restenoses developed within 1 year, revision of recurrent stenoses improved primary patency rates from 47% to 77% at 30 months. CONCLUSIONS: revision of early (<1 year) recurrent stenoses improves the mid-term patency rates of SFA remote endarterectomy.  相似文献   
80.
Plasma clearance of inulin (Cin), 99mTc-DTPA (CDTPA), and urographic contrast media (CCM) were determined simultaneously in 31 patients with varying levels of renal function evaluated in the setting of affiliated cardiac and renal transplantation programs. Cin and CDTPA were calculated from the ratio of simultaneously measured plasma concentration and urine excretion rate of these test agents (UxV/P). CCM was derived from x-ray fluorescence measurement of plasma iodine (PI) content following intravenous injection of 50 ml of nonionic, low-osmolar contrast media (180 mg I/ml). Urine collections were not required for CCM determinations. No adverse reactions attributable to CM occurred in any patient, and follow-up serum-creatinine values did not differ significantly from prestudy levels. CCM determined from the rate of decline in PI between 3 hr and 4 hr following administration of contrast media ("slope-intercept" technique) [Ccm-SI] correlated closely with corresponding levels of Cin (r = .86, P less than 0.0001). and CDTPA (r = 0.89, P less than 0.0001). Mean CCM-SI/Cin and CCM-SI/CDTPA ratios for the entire study cohort were 1.09 +/- 0.06 and 1.08 +/- 0.06, respectively. CCM-SI determinations also correlated well with CCM levels derived from a single measurement of PI ("single sample" technique) made at 3 hr following injection of contrast media (r = 0.94, P less than 0.0001). Both CCM-SI and CCM determined by the "single sample" method (CCM-3 degrees SS) tended to overestimate Cin and CDTPA, however, when the latter were less than 20 ml/min/1.73 m2 (mean CCM-SI/Cin and Ccm-3 degrees SS/Cin ratios 1.36 +/- 0.14 and 1.95 +/- 1.0, respectively. Reproducibility was evaluated by paired comparison of 3-hr vs. 4-hr "single sample" CCM determinations (r = 0.99, P less than 0.0001). In addition, analysis of the variation in iodine content between duplicate specimens obtained at each of these time intervals revealed a mean ratio of 1.0 +/- 0.01 (P = NS vs. identity). Contrast clearance determination utilizing the slope-intercept method is accurate, safe, pragmatic, and more precise than serum-creatinine and endogenous-creatinine clearance for measurement of renal function in clinical transplantation.  相似文献   
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