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101.
BACKGROUND: Resection offers the only chance of cure for hepatic colorectal metastases. However, preoperative staging does not always reliably detect unresectable disease. The aim of this study was to investigate the role that laparoscopy with ultrasound may have in detecting unresectable disease, thus sparing patients from unnecessary laparotomy with the associated morbidity and cost. METHODS: A retrospective review of all patients considered for liver resection of colorectal metastases during a 3-year period was performed, analyzing factors likely to predict resectable disease, rates of resectability, and success of laparoscopic staging at detecting unresectable disease. RESULTS: Of 73 patients with resectable disease on computed tomography, 24 were deemed to need laparoscopy, and 49 proceeded directly to laparotomy. Those first undergoing laparoscopy had shorter disease-free intervals between diagnosis of colorectal cancer and detection of hepatic recurrence and greater numbers of hepatic metastases. Twelve of the 24 patients who underwent laparoscopy had unresectable disease, and 8 of these were detected at laparoscopy. Forty-six of the 49 patients proceeding to laparotomy directly had resectable disease. CONCLUSIONS: Laparoscopic staging of hepatic colorectal metastatic disease detects most unresectable disease, preventing unnecessary laparotomy. The likelihood of disease being unresectable is in part predicted by the disease-free interval and the number of hepatic metastases.  相似文献   
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BACKGROUND: The reported frequency of gastrointestinal (GI) tract involvement in patients with mantle cell lymphoma (MCL) is 15-30%. However, this figure most likely is an underestimate because most patients with MCL involving the GI tract previously reported were examined endoscopically only if they had GI tract symptoms. The impact of endoscopic assessment on the management of MCL patients is unknown. METHODS: From March 1998 to May 2001 baseline upper and lower endoscopy of the GI tract was performed in consecutive untreated patients with MCL as part of a prospective therapeutic trial. Biopsies were performed on abnormal as well as macroscopically normal mucosa. Endoscopy was repeated during treatment and as part of follow-up evaluations. RESULTS: Only 26% of patients presented with GI symptoms at the time of diagnosis. MCL was present histologically in the lower GI tract of 53 of 60 patient (88%) and in the upper GI tract of 28 of 58 patients (43%). Microscopic evidence of MCL was found in 84% of patients with normal visual (macroscopic) findings by lower endoscopy and in 45% of patients with macroscopically normal findings by upper endoscopy. Despite this high frequency of GI tract involvement, the use of upper and lower endoscopy with biopsies in this group of patients resulted in changes in clinical management in only three (4%) patients. CONCLUSIONS: Gastrointestinal tract involvement was found to be present in most patients with MCL, usually at a microscopic level involving macroscopically normal mucosa. The use of aggressive staging evaluation of the GI tract was found to have little impact on patient management decisions in the current study.  相似文献   
104.
The effect of cyclophosphamide (Cp) on the glycolytic rate of radiation-induced fibrosarcomas (RIF-1) was measured in vivo in C3H mice by following the production of [3-(13)C]lactate after tail vein infusion of labeled [1-(13)C]glucose. Cp administered i.p. at a dose of 300 mg/kg caused a significant drop in glycolytic rate 24 h after treatment (P < 0.01). This drop was accompanied by an increase in [C-3]/[C-4] glutamate ratio in perchloric acid extracts of the tumors, indicating an increase in the Kreb's cycle activity. Treatment with Cp led to a significant decrease (P < 0.01) in tissue pO(2), measured in vivo with an oxygen Eppendorf electrode. Increases in NADH levels were also observed in rapidly frozen excised tumors examined by three-dimensional optical redox scanning. A significant decrease in tumor pO(2) and an increase in the NADH levels are suggestive of an increase in oxygen consumption by these tumors after Cp treatment. Overall, these data indicate that the reduction in glycolytic rate of Cp-treated RIF-1 tumors is due to an increase in aerobic metabolism.  相似文献   
105.
A series of new furanopeptides (3) are prepared by the coupling of arylsubstituted furoic acids (1) with amino acid methyl esters, di and tetra-peptide methyl esters using dicyclohexyl carbodiimide (DCC) as coupling agent. Some of the newly synthesized compounds are characterized on the basis of IR, 1H NMR, mass spectral data and elemental analysis. Some of the selected compounds are also tested for their antibacterial properties.  相似文献   
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Limonoids from the neem tree (Azadirachta indica) have attracted considerable research attention for their cytotoxicity against human cancer cell lines. However, the antiproliferative and apoptosis inducing effects of neem limonoids have not been tested in animal tumour models. The present study was therefore designed to evaluate the relative chemopreventive potential of the neem limonoids azadirachtin and nimbolide in the hamster buccal pouch (HBP) carcinogenesis model by analyzing the expression of proliferating cell nuclear antigen (PCNA), p21waf1, cyclin D1, glutathione S-transferase pi (GST-P), NF-κB, inhibitor of κB (IκB), p53, Fas, Bcl-2, Bax, Bid, Apaf-1, cytochrome C, survivin, caspases-3, −6, −8 and −9, and poly(ADP-ribose) polymerase (PARP) by RT-PCR, immunohistochemical, and Western blot analyses. The results provide compelling evidence that azadirachtin and nimbolide mediate their antiproliferative effects by downregulating proteins involved in cell cycle progression and transduce apoptosis by both the intrinsic and extrinsic pathways. On a comparative basis, nimbolide was found to be a more potent antiproliferative and apoptosis inducing agent and offers promise as a candidate agent in multitargeted prevention and treatment of cancer.  相似文献   
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Background and Aim:  Rigid proctoscopy, the gold standard for detecting hemorrhoids, has become a neglected procedure in the era of flexible endoscopy. Evaluation of hemorrhoids is often done with the retroflexed fiberoptic colonoscope. The aim of this study was to evaluate the technique of videoanoscopy in comparison with retroflexion of colonoscope in the rectum to detect hemorrhoids and to correlate objective findings of hemorrhoids and their relation to bleeding.
Methods:  In total, 544 patients were screened and 358 patients were evaluated by the technique of videoanoscopy and retroflexion of colonoscope in the rectum. The video images of both the procedures were independently analyzed by two observers for the presence or absence of hemorrhoids. The videoanoscopy images were also analyzed for number of columns of hemorrhoids, size and presence of red-color sign.
Results:  Videoanoscopy detected hemorrhoids in a significantly higher number of subjects when compared with retroflexion of colonoscope in the rectum by both observers ( P  < 0.05). The average kappa value was 0.637 and 0.779 for retroflexed colonoscopy and videoanoscopy, respectively. Red-color sign was present in 80.5% of patients with bleeding compared with only 30.3% in the non-bleeding group. The majority (71%) of patients in the bleeding group had larger hemorrhoids. Red-color sign and size of hemorrhoidal columns correlated with bleeding ( P  < 0.05).
Conclusion:  Videoanoscopy is a simple technique with increased sensitivity to detect hemorrhoids compared with intrarectal retroflexion of colonoscope and yields valuable objective information about the presence and condition of hemorrhoids. It should be performed as an extension of standard colonoscopy.  相似文献   
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