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91.
Ischaemic colitis (IC) is the most frequent form of gastrointestinal ischaemia. Discrepancy between non-specific symptoms and objective findings is a hallmark of IC. Thus delay of diagnosis is common due to its often subtle and unpredictable presentation. In particular, the clinical symptoms and signs of IC can overlap with those of inflammatory bowel disease. We present a case of a young man with known factor-V-Leiden mutation in whom IC developed during effective therapy with oral anticoagulants, presenting with symptoms and endoscopic findings suggestive of inflammatory bowel disease.  相似文献   
92.
OBJECTIVE: The objective of this study was to evaluate the prognostic significance of preoperative positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) by calculating the mean standardized uptake values (SUV) in patients with resectable soft tissue sarcomas (STS). SUMMARY AND BACKGROUND DATA: FDG-PET might be used as an adjunctive tool (in addition to biopsy and radiologic tomography) in the preoperative prognostic assessment of resectable STS. METHODS: A total of 74 adult patients with STS underwent preoperative FDG-PET imaging with calculation of the SUV. Clinicopathologic data and the SUV were analyzed for an association with the clinical outcome. The first and the third quartiles of the SUV distribution function were used as cutoff values (1.59 and 3.6). Survival was estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed using log-rank test and the Cox proportional hazards regression model. RESULTS: In 55 cases, STS were completely resected (follow up 40 months): 5-year recurrence-free survival rates in patients with SUV <1.59, 1.59 to <3.6, and > or =3.6 were 66%, 24%, and 11%, respectively (P = 0.0034). SUV was a predictor for overall survival (5-year rates: 84% [SUV <1.59], 45% [SUV 1.59 to <3.6], and 38% [SUV > or =3.6]; P = 0.057) and local tumor control (5-year rates: 93% [SUV <1.59], 43% [SUV 1.59 to <3.6], and 15% [SUV > or =3.6]; P = 0.0017). By multivariate analysis, SUV was found to be predictive for recurrence-free survival. The prognostic differences with respect to the SUV were associated with tumor grade (P = 0.002). CONCLUSION: The semiquantitative FDG uptake, as measured by the mean SUV on preoperative PET images in patients with resectable STS, is a useful prognostic parameter. SUV with cutoff values at the first and the third quartiles of the SUV distribution predicted overall survival, recurrence-free survival, and local tumor control. Therefore, FDG-PET can be used to improve the preoperative prognostic assessment in patients with resectable STS.  相似文献   
93.
PURPOSE: Data on the actual uptake of genetic testing for hereditary nonpolyposis colorectal cancer (HNPCC) in a clinical sample is still inconclusive. The present study aimed to define the actual uptake of genetic counseling and testing offered to an unselected sample of 140 patients with colorectal cancer, fulfilling clinical criteria (Amsterdam or Bethesda) suggestive of HNPCC, and to identify demographic and psychosocial factors associated with the decision to participate in counseling. METHODS: Crosssectional survey. Eligible subjects had been consecutively enrolled in a regional tumor registry between 1994 and 1998, and were invited to attend an information session for HNPCC at the time genetic testing for HNPCC became available. Participants and nonparticipants in the information session completed a short questionnaire. RESULTS: The actual uptake rate of the information session in this sample was 26 percent. Participants and nonparticipants were comparable with regard to clinical criteria suggestive of HNPCC, awareness of the potential hereditary predisposition, and previous history of cancer in the family. Some 60 percent of participants experienced pronounced distress related to their potential inheritance of the disorder, compared to 35 percent among nonparticipants. Distress reached a clinically significant level in 28 percent of participants. Restricted communication within the family was observed frequently. Irrespective of groups, a positive attitude toward obtaining a gene test result predominated. CONCLUSIONS: Results suggest that expressed intention and attitude toward genetic testing do not reliably predict actual uptake of counseling or testing. Thorough interdisciplinary counseling should be provided to every patient with clinical criteria suggestive of HNPCC. The considerable distress related to the hereditary disorder should be adequately addressed, as should be communication issues.  相似文献   
94.
Neoplastic progression of solid tumours is often characterized by a simultaneous increase in matrix protein (eg collagen) synthesis and degradation, and results in the formation of a tumour stroma. At the tumour periphery, this process is believed to facilitate angiogenesis and invasive growth of tumour cells. In various types of carcinoma, differentiation of fibroblasts towards myofibroblasts is thought to play an important role in extracellular matrix remodelling as their emergence coincides with architectural changes in the tumour stroma. Here, distinct architectural changes in collagen fibres are reported in cutaneous squamous cell carcinomas (cSCC) with respect to normal skin and precursor lesions, ie keratinocytic intraepidermal neoplasia (KIN). Simultaneously, type I collagen mRNA was observed in fibroblasts in close proximity to cSCC lesions (19/19) but only in 2 of 10 KIN lesions tested. Interestingly, whereas emerging of myofibroblasts correlated with reduced differentiation of cSCCs, it was not a prerequisite for type I collagen synthesis. These data indicate that type I collagen synthesis by fibroblasts parallels the malignant transformation of human KIN to cSCC.  相似文献   
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The release of Streptomyces albus propagules from contaminated agar and ceiling tile surfaces was studied under controlled environmental conditions in a newly developed aerosolization chamber. The experiments revealed that both spores and cell fragments can be simultaneously released from the colonized surface by relatively gentle air currents of 0.3 ms(-1). A 100 x increase of the air velocity can result in a 50-fold increase in the number of released propagules. The aerosolization rate depends strongly on the type and roughness of the contaminated surface. Up to 90% of available actinomycete propagules can become airborne during the first 10 min of the release process. Application of vibration to the surface did not reveal any influence on the aerosolization process of S. albus propagules under the tested conditions. This study has shown that propagules in the fine particle size range can be released in large amounts from contaminated surfaces. Measurement of the number of S. albus fragments in the vicinity of a contaminated area, as an alternative to conventional air or surface sampling, appears to be a promising approach for quantitative exposure assessment.  相似文献   
98.
Background and aims There have been many supportive data that the pylorus-preserving pancreatoduodenectomy (PPPD) might be equal to the classic Whipple pancreatoduodenectomy (PD) in terms of oncological radicality. However, few reports are available on the early postoperative and enduring functional changes, nutritional status, body composition, and quality of life years after surgery. The aim of this study was to compare nutritional and functional results of the different techniques in a retrospective evaluation and prospective cohort study.Patients and methods In May 1998, the standard surgical approach in the Department of Surgery, University-Hospital Mannheim, changed from PD to PPPD. The early postoperative and enduring functional changes, quality of life, oncological radicality, and nutritional status after years were compared between 128 patients after PD and 111 patients after PPPD. In a retrospective manner, the intra- and postoperative course was evaluated. In survivors, we prospectively analyzed the functional, nutritional, and oncological outcomes after 54 months (mean) in PD and after 24 months (mean) in PPPD patients.Results The PPPD and PD groups did not differ according to age, gender, preoperative condition, or tumor localization. The PPPD group demonstrated favorable results (p<0.05) for operation time (PPPD 341±74 vs PD 386±89 min), blood loss (793±565 vs 1,000±590 ml), blood transfusions (416±691 vs 653±776 ml), delayed gastric emptying (6 vs 13%), and hospital stay (20 vs 24 days). However, a possible bias has to be mentioned since more T4 stages were diagnosed in the PD group (3 vs 11%), and even more extended (venous) resections were performed in the PD group (7 vs 24%). Morbidity (32 vs 30%) and mortality (5 vs 3%) did not differ between the two groups. After 24 months (PPPD, n=22) and 54 months (PD, n=16), there was no difference in global quality of life in recurrence-free patients. While the preoperative body weight was reached after 4 months (median) in the PPPD group, it was reached after 6 months (p<0.05) in the PD group. Bioelectrical impedance analysis (BIA) revealed a significantly (p<0.05) lower total body water (55 vs 60%) and significantly higher total body fat (26 vs 18%) in PPPD than in PD patients. Long-term follow-up showed no significant statistical differences in survival between both groups.Conclusion Besides favorable postoperative outcome in specific aspects and equal oncological outcome of PPPD, pylorus preservation seems to have advantages in enduring functional and nutritional status years after surgery for pancreatic cancer.Marco Niedergethmann, M.D. and Edward Shang, M.D., contributed to this work equally.  相似文献   
99.
Irinotecan (CPT-11) has been shown to prolong survival and improve quality of life in comparison to best supportive care in colorectal cancer patients with pretreatment of bolus 5-fluorouracil (5-FU). After first-line 24-h high-dose (HD) 5-FU/folinic acid (FA) an objective response rate of 11% with 3-weekly CPT-11 350 mg/m was reported. In the present study we investigated weekly CPT-11 in combination with 24-h HD-5-FU/FA as second-line treatment after prior exposure to 24-h HD-5-FU. Synergy between 5-FU and CPT-11 is the rationale to combine both substances for second-line therapy in order to overcome resistance to 5-FU. Thirty-five patients were recruited in a single institution to receive 6 x weekly CPT-11 80 mg/m(2), FA 200 mg/m(2) and 24-h HD-5-FU 2000 mg/m(2). Treatment was repeated on day 57. Patient characteristics: M/F=20/15, median WHO performance status 1, range (0-2). Thirty-four patients were evaluable for response: partial response 17% and no change 40%. Median time to progression and overall survival were 3.3 and 8.4 months, respectively. All patients were evaluable for toxicity analysis (National Cancer Institute Common Toxicity Criteria grade 3): leukocytopenia 3%, diarrhea 12% and vomiting/nausea 6%. Of the assigned doses, a median 100% of 5-FU and 92% of CPT-11 were administered during the first cycle of chemotherapy. We conclude that weekly CPT-11 and HD-5-FU/FA is an active and safe combination chemotherapy resulting in response rates in the upper range of other CPT-11-based second-line regimen. The toxicity profile in our series compared to 3-weekly CPT-11 seems favorable.  相似文献   
100.
Since the NIH recommendations in 1990 the majority of patients with rectal cancer are treated by a multimodality approach. The last decade has seen considerable improvements in the overall management of rectal cancer, therefore a certain reorientation seems justified. Although many questions remain to be answered, some general recommendations for the treatment of rectal cancer focussed on the small pelvis can be given. Surgery with total mesorectal excision is the standard therapy for cancers of the middle and low rectum in stages T1/2 N0. Adjuvant radiochemotherapy and shortterm pre-operative radiotherapy are both feasible approaches for the treatment of stage II and stage III rectal carcinomas. The superiority of either concept awaits clarifying randomised trials. Patients with T4 rectal cancers should undergo long-term neoadjuvant radiochemotherapy with consecutive oncological resection. The exact mode of the neoadjuvant regimen combining high remission rates with low treatment-associated morbidity needs further refinements. Local excision should be restricted to patients with well-differentiated, less than semi-circumferential T1 carcinomas. Tumours with less favourable histologies should not be treated locally unless general patient conditions forbid oncological resections. In these instances, additional radiochemotherapy appears able to reduce the risk of local recurrence.  相似文献   
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