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1.
Patients with long-standing inflammatory bowel disease(IBD)involving at least 1/3 of the colon are at increased risk for colorectal cancer(CRC).Advancements in CRC screening and surveillance and improved treatment of IBD has reduced CRC incidence in patients with ulcerative colitis and Crohn’s colitis.Most cases of CRC are thought to arise from dysplasia,and recent evidence suggests that the majority of dysplastic lesions in patients with IBD are visible,in part thanks to advancements in high definition colonoscopy and chromoendoscopy.Recent practice guidelines have supported the use of chromoendoscopy with targeted biopsies of visible lesions rather than traditional random biopsies.Endoscopists are encouraged to endoscopically resect visible dysplasia and only recommend surgery when a complete resection is not possible.New technologies such as virtual chromoendoscopy are emerging as potential tools in CRC screening.Patients with IBD at increased risk for developing CRC should undergo surveillance colonoscopy using new approaches and techniques.  相似文献   

2.
Twenty years after its introduction,computed tomographic colonography(CTC)has reached its maturity,and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer(CRC)and polyps.This examination technique is less invasive than colonoscopy(CS),easy to perform,and standardized.Reduced bowel preparation and colonic distention using carbon dioxide favor patient compliance.Widespread implementation of a new image reconstruction algorithm has minimized radiation exposure,and the use of dedicated software with enhanced views has enabled easier image interpretation.Integration in the routine workflow of a computer-aided detection algorithm reduces perceptual errors,particularly for small polyps.Consolidated evidence from the literature shows that the diagnostic performances for the detection of CRC and large polyps in symptomatic and asymptomatic individuals are similar to CS and are largely superior to barium enema,the latter of which should be strongly discouraged.Favorable data regarding CTC performance open the possibility for many different indications,some of which are already supported by evidence-based data:incomplete,failed,or unfeasible CS;symptomatic,elderly,and frail patients;and investigation of diverticular disease.Other indications are still being debated and,thus,are recommended only if CS is unfeasible:the use of CTC in CRC screening and in surveillance after surgery for CRC or polypectomy.In order for CTC to be used appropriately,contraindications such as acute abdominal conditions(diverticulitis or the acute phase of inflammatory bowel diseases)and surveillance in patients with a long-standing history of ulcerative colitis or Crohn’s disease and in those with hereditary colonic syndromes should not be overlooked.This will maximize the benefits of the technique and minimize potential sources of frustration or disappointment for both referring clinicians and patients.  相似文献   

3.
Patients with inflammatory bowel disease(IBD)are at increased risk for developing colorectal cancer(CRC),although the overall incidence of IBD-associated CRC has been diminishing in recent decades in western countries.As demonstrated in previous studies,the risk of CRC in IBD increases with longer duration,extent of colitis,a familial history of CRC,coexistent primary sclerosing cholangitis,and the degree of inflammation.The pathogenesis of CRC in IBD is poorly understood.Similar to sporadic CRC,IBD-associated CRC is a consequence of sequential episodes of genomic alteration.Multiple inter-related pathways,including immune response by mucosal inflammatory mediators,oxidative stress,and intestinal microbiota,are also involved the pathogenesis of IBD-associated CRC.Continuing colonic inflammation appears to be a factor in the development of CRC;therefore,anti-inflammatory agents such as5-aminosalicylate compounds and immune modulators have been considered as potential chemopreventive agents.Colonoscopic surveillance is widely accepted as being effective in reducing the risk of IBD-associated CRC,although no clear evidence has confirmed that surveillance colonoscopy prolongs survival in patients with extensive colitis.The traditional recommendation has been quadrantic random biopsies throughout the entire colon;however,several guidelines now have endorsed chromoendoscopy with a target biopsy because of increasing diagnostic yields and reduced workloads for endoscopists and pathologists.New technologies such as narrow band imaging,confocal endomicroscopy,and autofluorescence imaging have not yet been confirmed as surveillance strategies in IBD.  相似文献   

4.
Surveillance for hepatocellular carcinoma(HCC)is considered a standard of care for patients with chronic liver disease who are at risk of developing this malignancy.Several studies have shown that surveillance can improve the prognosis of patients diagnosed with HCC through an increased likelihood of application of curative or effective treatments.Repetition of liver ultrasonography(US)every 6 mo is the recommended surveillance program to detect early HCCs,and a positive US has to entrain a well-defined recall policy based on contrast-enhanced,dynamic radiological imaging or biopsy for the diagnosis of HCC.Although HCC fulfills the accepted criteria regarding cost-effective cancer screening and surveillance,the implementation of surveillance in clinical practice is defective and this has a negative impact on the cost-effectiveness of the procedure.Education of both physicians and patients is of paramount importance in order to improve the surveillance application and its benefits in patients at risk of HCC.The promotion of specific educational programs for practitioners,clinicians and patients is instrumental in order to expand the correct use of surveillance in clinical practice and eventually improve HCC prognosis.  相似文献   

5.
Evidence has now accumulated that colonoscopy and removal of polyps,especially during screening and surveillance programs,is effective in overall risk reduction for colon cancer.After resection of malignant pedunculated colon polyps or early stage colon cancers,long-term repeated surveillance programs can also lead to detection and removal of asymptomatic high risk advanced adenomas and new early stage metachronous cancers.Early stage colon cancer can be defined as disease that appears to have been completely resected with no subsequent evidence of involvement of adjacent organs,lymph nodes or distant sites.This differs from the clinical setting of an apparent"curative"resection later pathologically upstaged following detection of malignant cells extending into adjacent organs,peritoneum,lymph nodes or other distant sites,including liver.This highly selected early stage colon cancer group remains at high risk for subsequent colon polyps and metachronous colon cancer.Precise staging is important,not only for assessing the need for adjuvant chemotherapy,but also for patient selection for continued surveillance.With advanced stages of colon cancer and a more guarded outlook,repeated surveillance should be limited.In future,novel imaging technologies(e.g.,confocal endomicroscopy),coupled with increased pathological recognition of high risk markers for lymph node involvement(e.g.,"tumor budding")should lead to improved staging and clinical care.  相似文献   

6.
AIM: To compare the results from computed tomography (CT) colonography with conventional colonoscopy in symptomatic patients referred for colonoscopy. METHODS: The study included 227 adult outpatients, mean age 60 years, with appropriate indications for colonoscopy. CT colonography and colonoscopy were performed on the same day in a metropolitan teaching hospital. Colonoscopists were initially blinded to the results of CT colonography but there was segmental unblinding during the procedure. The primary outcome measures were the sensitivity and specificity of CT colonography for the identification of polyps seen at colonoscopy (i.e. analysis by polyp). Secondary outcome measures included an analysis by patient, extracolonic findings at CT colonography, adverse events with both procedures and patient acceptance and preference. RESULTS: Twenty-five patients (11%) were excluded from the analysis because of incomplete colonoscopy or poor bowel preparation that affected either CT colonography, colonoscopy or both procedures. Polyps and masses (usually cancers) were detected at colonoscopy and CT colonography in 35% and 42% of patients, respectively. Of nine patients with a final diagnosis of cancer, eight (89%) were identified by CT colonography as masses (5) or polyps (3). For polyps analyzed according to polyp, the overall sensitivity of CT colonography was 50% (95% CI, 39%-61%) but this increased to 71% (95% CI, 52%-85%) for polyps ≥ 6 mm in size. Similarly, specificity for all polyps was 48% (95% CI, 39%-58%) increasing to 67% (95% CI, 56%-76%) for polyps ≥6 mm. Adverse events were uncommon but included one colonic perforation at colonoscopy, Patient acceptance was high for both procedures but preference favoured CT colonography. CONCLUSION: Although CT colonography was more sensitive in this study than in some previous studies, the procedure is not yet sensitive enough for widespread application in symptomatic patients.  相似文献   

7.
Screening for colorectal cancer(CRC) has been associated with a decreased incidence and mortality from CRC.However,patient adherence to screening is less than desirable and resources are limited even indeveloped countries.Better identification of individuals at a higher risk could result in improved screening efforts.Over the past few years,formulas have been developed to predict the likelihood of developing advanced colonic neoplasia in susceptible individuals but have yet to be utilized in mass screening practices.These models use a number of clinical factors that have been associated with colonic neoplasia including the body mass index(BMI).Advances in our understanding of the mechanisms by which obesity contributes to colonic neoplasia as well as clinical studies on this subject have proven the association between BMI and colonic neoplasia.However,there are still controversies on this subject as some studies have arrived at different conclusions on the influence of BMI by gender.Future studies should aim at resolving these discrepancies in order to improve the efficiency of screening strategies.  相似文献   

8.
Ulcerative colitis in addition to inflammatory polyposis is common.The benign sequel of ulcerative colitis can sometimes mimic colorectal carcinoma.This report describes a rare case of inflammatory polyposis with hundreds of inflammatory polyps in ulcerative colitiswhich was not easy to distinguish from other polyposis syndromes.A 16-year-old Chinese male suffering from ulcerative colitis for 6 mo underwent colonoscopy,and hundreds of polyps were observed in the sigmoid,causing colonic stenosis.The polyps were restricted to the sigmoid.Although rectal inflammation was detected,no polyps were found in the rectum.A diagnosis of inflammatory polyposis and ulcerative colitis was made.The patient underwent total colectomy and ileal pouch anal anastomosis.The patient recovered well and was discharged on postoperative day 8.Endoscopic surveillance after surgery is crucial as ulcerative colitis with polyposis is a risk factor for colorectal cancer.Recognition of polyposis requires clinical,endoscopic and histopathologic correlation,and helps with chemoprophylaxis of colorectal cancer,as the drugs used postoperatively for colorectal cancer,ulcerative colitis and polyposis are different.  相似文献   

9.
The association between inflammatory bowel disease(IBD)and colorectal cancer(CRC)has been acknowledged for almost a century and is assumedly promoted by a chronic inflammation-driven carcinogenic process in the intestine in combination with a genetic predisposition.The magnitude of the risk of CRC in IBD remains a continuing subject of debate.The early,high risk estimates for CRC in IBD were most likely overestimated due to selected patient populations originating from tertiary referral centers with a disproportional high percentage of patients with severe disease.Later population-based studies calculating risk estimates from a broad spectrum of IBD patients have found the risk to be significantly lower.At present,there is evidence that IBD patients with longstanding and extensive disease with uncontrolled inflammation are those at increased risk.Additional,other recognized risk factors include early age at onset,family history of CRC,and concomitant primary sclerosing cholangitis.A significant amount of effort is put into identifying potential preventive factors of CRC in IBD,including surveillance programs and chemopreventive agents but the individual effect of these remains uncertain.Interestingly,recent studies have reported a decline in risk of CRC over time.Surveillance programs and the new treatment strategies,particular biological treatment might be part of the reason for the observed decline in risk of CRC in IBD over time but future studies will have investigate this assumption.  相似文献   

10.
AIM To evaluate the National Cancer Institute(NCI)Colorectal Cancer(CRC)Risk Assessment Tool as a predictor for the presence of adenomatous polyps(AP) found during screening or surveillance colonoscopy.METHODS This is a retrospective single center observational study.We collected data of adenomatous polyps in each colonoscopy and then evaluated the lifetime CRC risk.We calculated the AP prevalence across risk score quintiles,odds ratios of the prevalence of AP across risk score quintiles,area under curves(AUCs)and Youden’s indexes to assess the optimal risk score cut off value for AP prevalence status.RESULTS The prevalence of AP gradually increased throughout the five risk score quintiles:i.e.,27.63%in the first and 51.35%in the fifth quintile.The odd ratios of AP prevalence in the fifth quintile compared to the first and second quintile were 2.76[confidence interval(CI):1.71-4.47]and 2.09(CI:1.32-3.30).The AUC for all patients was 0.62(CI:0.58-0.66).Youden’s Index indicated the optimal risk score cutoff value discriminating AP prevalence status was 3.60.CONCLUSION Patients with the higher NCI risk score have higher risk of AP and subsequent CRC;therefore,measures to increase the effectiveness of CRC detection in these patients include longer withdrawal time,early surveillance colonoscopy,and choosing flexible colonoscopy over other CRC screening modalities.  相似文献   

11.
Colorectal cancer (CRC) remains a leading cancer killer worldwide. But the disease is both curable and preventable at an early stage. Regular CRC cancer screening has been shown to reduce the risk of dying from CRC. However, the importance of large-scale screening is only now starting to be appreciated. This article reviews a variety of imaging procedures available for detecting ulcerative colitis (UC) and Crohn's disease (CD), polyps and CRC in their early stage and also presents details on various screening options. Detecting, staging and re-staging of patients with CRC also require multimodality, multistep imaging approaches. Staging and re-staging with conventional colonoscopy (CC), computer tomography colonography (CTC), magnetic resonance colonography (MRC) and positron emission tomography/computer tomography colonography (PET/CTC) are of paramount importance in determining the most appropriate therapeutic method and in predicting the risk of tumor recurrence and overall prognosis. The advantages and limitations of these modalities are also discussed.  相似文献   

12.
AIM To identify the prevalence, and clinical and pathologic characteristic of colonic polyps among Iranian patients undergoing a comprehensive colonoscopy, and determine the polyp detection rate(PDR) and adenoma detection rate(ADR).METHODS In this cross-sectional study, demographics and epidemiologic characteristics of 531 persons who underwent colonoscopies between 2014 and 2015 at Mehrad gastrointestinal clinic were determined. Demographics, indication for colonoscopy, colonoscopy findings, number of polyps, and histopathological characteristics of the polyps were examined for each person.RESULTS Our sample included 295(55.6%) women and 236(44.4%) men, with a mean age of 50.25 ± 14.89 years. Overall PDR was 23.5%(125/531). ADR and colorectal cancer detection rate in this study were 12.8% and 1.5%, respectively. Polyps were detected more significantly frequently in men than in women(52.8% vs 47.2%, P 0.05). Polyps can be seen in most patients after the age of 50. The average age of patients with cancer was significantly higher than that of patients with polyps(61.3 years vs 56.4 years, P 0.05). The majority of the polyps were adenomatous. More than 50% of the polyps were found in the rectosigmoid part of the colon.CONCLUSION The prevalence of polyps and adenomas in this study is less than that reported in the Western populations. In our patients, distal colon is more susceptible to developing polyps and cancer than proximal colon.  相似文献   

13.
AIM: To examine the diagnostic yield of colorectal neoplasia at computed tomographic colonoscopy (CTC) as well as the feasibility of contrast enhanced CTC in patients with gastric cancer. METHODS: To examine the incidence of colon polyp we selected postoperative 188 gastric cancer patients, which we refer to as the 'colon polyp survey group'. To examine the feasibility of CTC for early detection of colon cancer or advanced colon adenoma, we selected 47 gastric cancer patients (M:F 29:18, mean age 53.8 years), which we call the 'CT colonoscopy group'. All the 47 patients underwent successive CTC and colonoscopy on the same day. RESULTS: Totally 109 colon polyps were observed from 59 out of 188 gastric cancer patients, the incidence rate of colon polyps in gastric cancer patients being 31.4%. The sensitivity of CTC in detecting individuals with at least 1 lesion of any size was 57.1%, the specificity was 72.7%, the positive predictive value was 47.1%, and the negative predictive value was 71.9%. When the cutoff size was decreased to 6 mm, the sensitivity and specificity were 80.0% and 92.9%, respectively, with positive and negative predictive values of 57.1% and 97.5%, respectively. Only one patient was classified as false negative by virtual colonoscopy. CONCLUSION: The diagnostic yield of colorectal polyp was 31.4% in patients with gastric cancer, and contrast enhanced CTC is an acceptable tool for the detection of synchronous colorectal advanced adenoma andpostoperative surveillance of gastric cancer patients.  相似文献   

14.
AIM: To compare the endotics system (ES), a set of new medical equipment for diagnostic colonoscopy, with video-colonoscopy in the detection of polyps. METHODS: Patients with clinical or familial risk of colonic polyps/carcinomas were eligible for this study. After a standard colonic cleaning, detection of polyps by the ES and by video-colonoscopy was performed in each patient on the same day. In each single patient, the assessment of the presence of polyps was performed by two independent endoscopists, who were randomly assigned to evaluate, in a blind fashion, the presence of polyps either by ES or by standard colonoscopy. The frequency of successful procedures (i.e. reaching to the cecum), the time for endoscopy, and the need for sedation were recorded. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ES were also calculated. RESULTS: A total of 71 patients (40 men, mean age51.9 ± 12.0 years) were enrolled. The cecum was reached in 81.6% of ES examinations and in 94.3% of colonoscopies (P = 0.03). The average time of endoscopy was 45.1 ± 18.5 and 23.7 ± 7.2 min for the ES and traditional colonoscopy, respectively (P < 0.0001). No patient required sedation during ES examination, compared with 19.7% of patients undergoing colonoscopy (P < 0.0001). The sensitivity and specificity of ES for detecting polyps were 93.3% (95% CI: 68-98) and 100% (95% CI: 76.8-100), respectively. PPV was 100% (95% CI: 76.8-100) and NPV was 97.7% (95% CI: 88-99.9). CONCLUSION: The ES allows the visualization of the entire colonic mucosa in most patients, with good sensitivity/specificity for the detection of lesions and without requiring sedation.  相似文献   

15.
Pancreatic cancer is the 4th leading cause of cancerrelated death in Western countries.Considering the low incidence of pancreatic cancer,population-based screening is not feasible.However,the existence of a group of individuals with an increased risk to develop pancreatic cancer has been well established.In particular,individuals suffering from a somatic or genetic condition associated with an increased relative risk of more than 5-to 10-fold seem to be suitable for enrollment in a surveillance program for prevention or early detection of pancreatic cancer.The aim of such a program is to reduce pancreatic cancer mortality through early or preemptive surgery.Considering the risk associated with pancreatic surgery,the concept of preemptive surgery cannot consist of a prophylactic removal of the pancreas in high-risk healthy individuals,but must instead aim at treating precancerous lesions such as intraductal papillary mucinous neoplasms or pancreatic intraepithelial neoplasms,or early cancer.Currently,results from clinical trials do not convincingly demonstrate the efficacy of this approach in terms of identification of precancerous lesions,nor do they define the outcome of the surgical treatment of these lesions.For this reason,surveillance programs for individuals at risk of pancreatic cancer are thus far generally limited to the setting of a clinical trial.However,the acquisition of a deeper understanding of this complex area,together with the increasing request for screening and treatment by individuals at risk,will usher pancreatologists into a new era of preemptive pancreatic surgery.Along with the growing demand to treat individuals with precancerous lesions,the need for low-risk investigation,lowmorbidity operation and a minimally invasive approach becomes increasingly pressing.All of these considerations are reasons for preemptive pancreatic surgery programs to be undertaken in specialized centers only.  相似文献   

16.
AIM: To report our experience with computed tomography colonography (CTC) systematically performed in subjects with positive faecal occult blood test (FOBT) and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer (CRC).
METHODS: From April 2006 to April 2007, 43 290 individuals (age range 50-70) who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects (4.3%). 1463 (77.7%) of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 (7.2%) were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep (polyethyleneglycole) in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values (PPV) were calculated.
RESULTS: Twenty-one (50%) of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm.
CONCLUSION: In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.  相似文献   

17.
AIM:To investigate our clinical experience with the colonic manifestations of phosphatase and tensin homolog on chromosome ten(PTEN)hamartoma tumor syndrome(PHTS)and to perform a systematic literature review regarding the same.METHODS:This study was approved by the appropriate institutional review board prior to initiation.A clinical genetics database was searched for patients with PHTS or a component syndrome that received gastrointestinal endoscopy or pathology interpretation at our center.These patient’s records were retrospectively reviewed for clinical characteristics(including family history and genetic testing),endoscopy results and pathology findings.We also performed a systematic review of the literature for case series of PHTS or component syndromes that reported gastrointestinal manifestations and investigations published after consensus diagnostic criteria were established in 1996.These results were compiled and reported.RESULTS:Eight patients from our institution met initial inclusion criteria.Of these,5 patients underwent4.2 colonoscopies at mean age 45.8±10.8 years.All were found to have colon polyps during their clinical course and polyp histology included adenoma,hyperplastic,ganglioneuroma and juvenile.No malignant lesions were identified.Two had multiple histologic types.One patient underwent colectomy due to innumerable polyps and concern for future malignant potential.Systematic literature review of PHTS patients undergoing endoscopy revealed 107 patients receiving colonoscopy at mean age 37.4 years.Colon polyps were noted in92.5%and multiple colon polyp histologies were reported in 53.6%.Common polyp histologies included hyperplastic(43.6%),adenoma(40.4%),hamartoma(38.3%),ganglioneuroma(33%)and inflammatory(24.5%)polyps.Twelve(11.2%)patients had colorectal cancer at mean age 46.7 years(range 35-62).Clinical outcomes secondary to colon polyposis and malignancy were not commonly reported.CONCLUSION:PHTS has a high prevalence of colon polyposis with multiple histologic types.It should be considered a mixed polyposis syndrome.Systematic review found an increased prevalence of colorectal cancer and we recommend initiating colonoscopy for colorectal cancer surveillance at age 35 years.  相似文献   

18.
Homocysteine is an amino acid generated metabolically by the S-adenosylmethionine-dependent transmethylation pathway. In addition to being a well-known independent risk factor for coronary heart disease, is also a risk factor for cancer. Patients suffering from inflammatory bowel diseases(IBD) including ulcerative colitis and Crohn’s disease are at increased risk of developing colorectal cancer in comparison to healthy individuals. Furthermore, the risk of hyperhomocysteinaemia is significantly higher in IBD patients when compared with controls. In the present article, we review the mechanisms in which hyperhomocysteinemia may contribute to increased risk of colorectal cancer in IBD patients.  相似文献   

19.
AIM: To evaluate the association between colonic polyps and diverticular disease in Japan. METHODS: We retrospectively reviewed the medical records of 672 consecutive patients who underwent total colonoscopy between August 2006 and April 2007 at Nishinjo Hospital, Okinawa, Japan. Patients with a history of any of the following were excluded from the study: previous polypectomy, colonic resection, and inflammatory bowel diseases. The association between colonic polyps and diverticular disease was analyzed by logistic regression analysis, adjusted for age and sex. RESULTS: Prevalence of colonic polyps in all patients with diverticular disease was significantly higher than that in those without diverticular disease (adjusted odds ratio 1.7). CONCLUSION: Our data showed that patients with diverticular disease have a higher risk of colonic polyps compared to those without.  相似文献   

20.
Colon capsule endoscopy: What we know and what we would like to know   总被引:1,自引:0,他引:1  
Colonoscopy is usually perceived as an invasive and potentially painful procedure,being also affected by a small,but definite,risk of major complications(cardiopulmonary complications,perforation,hemorrhage)and even mortality.To improve both acceptability and safety,Pill Cam Colon Capsule Endoscopy(CCE)(Given Imaging Ltd,Yoqneam,Israel)has been developed.CCE represents a non-invasive technique that is able to explore the colon without sedation and air insufflation.The Second Generation of Colon Capsule Endoscopy(Pill Cam Colon 2)(CCE-2)was proven to be an accurate tool to detect colonic neoplastic lesions when used in average risk individuals.To date,the evidence supports the use of CCE-2 in case of colonoscopy failure,in patients unwilling to perform colonoscopy and when colonoscopy is contraindicated.Other potential applications,such as colorectal cancer screening or diagnostic surveillance ofinflammatory bowel disease need to be clarified.In this paper,the current“state of the art”,potential application of CCE and future needs are evaluated.  相似文献   

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