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991.
992.
There are various oral diseases related to tobacco habits. In the majority of these diseases there is a dose-response relationship. This is particularly true for premalignant lesions, such as leukoplakia, and squamous cell carcinoma. Patients should be informed about the deleterious effects of tobacco on the oral tissues. At the same time the patient should know that cessation of the tobacco habits does eliminate the increased risk of developing oral precancer and cancer within a reasonable period of time.  相似文献   
993.
The present study reports the final analysis of a randomized controlled clinical trial in which different designs of posterior resin-bonded bridges were evaluated for a period of at least 5 years. The operational hypothesis was that the bonding system and the preparation design used in posterior resin-bonded bridges have an influence on the survival and clinical functioning of these restorations. Survival in this study was defined at two levels: (1) 'primary' survival (survival without any debonding), and (2) 'functional' survival (survival including loss of retention on one occasion and successful rebonding of the original resin-bonded bridge without further debonding). Preparation of grooves in abutment teeth for posterior resin-bonded bridges appeared to be beneficial to their chance of survival. Resin-bonded bridges placed in the maxilla have a better prognosis than those made in the mandible. The bonding systems used in this study (etching/Clearfil F2, sand blasting/Panavia EX and silica-coating/Microfill Pontic C) appear to have no influence on the chance of failure with regards to the 'primary' survival. In rebonded posterior resin-bonded bridges, the bonding system silica coating/Microfill Pontic C was more retentive than the other systems tested.  相似文献   
994.
Patients with Parkinson's disease(PD) show a serious decrease in performance on tasks which lack explicit guidelines and which necessitate the subject to develop his or her own strategy. Using the California Verbal Learning Task(CVLT) we have found evidence that this phenomenon becomes also manifest in learning and memory. The goal of the present study on PD was to investigate whether or not there is an intrinsic relationship between PD-specific deviant learning characteristics and the severity of motor symptomatology. The results show, as expected, a significant correlation between the severity of bradykinetic/hypokinetic symptoms and the serial clustering gradient of the CVLT: the more bradykinetic PD patients (n = 48) were, the more they were dependent on the externally guided serial learning strategy. The findings are discussed in the context of our hypothesis that the actual deficit in patients with PD is a deficient processing of ambiguous internal cues.  相似文献   
995.
996.
A previous study showed that measurements of total-body bone mineral changes made with a Hologic QDR 1000W were unreliable when the subjects underwent weight change. The study has been extended to dual energy X-ray absorptiometry (DXA) apparatus from other manufacturers. Re-analysis of published results during weight loss using a Lunar DPX showed that they varied with the software used. Using the Extended mode, there was a 1% loss of bone mineral areal density (BMD), but no significant change in bone mineral content (BMC) or bone area (BA) following a weight loss of 16 kg, whereas the use of the Standard mode led to a larger fall of BMC and BMD. Similar findings arose from the consideration of two studies using Norland XR 26 HS absorptiometers. On the other hand, separation of two groups with similar weight changes from the population studied with a Hologic QDR 1000W confirmed that BMC changed directly with weight, but there was an inverse relationship for BMD, owing to an inappropriate change of BA. The use of Hologic Enhanced and Standard software modes led to significant differences in initial readings and measured changes. With each instrument there was a strong correlation between changes in BA and changes in BMC. When 6 kg of lard was wrapped around the limbs of volunteers or a semi-anthropomorphic phantom to simulate weight change, there were spurious increases of measured BMC and BA by about 5% with each instrument. There were no changes of BMD with Lunar, variable results with Norland, but decreases with Hologic. The results observed in vivo could be explained by the effects of fat changes, without there being any real change of bone mineral. Changes of BMD in the skeleton of the phantom were underestimated with all three brands. The anomaly observed with the Hologic QDR 1000W is less apparent with a Lunar DPX or a Norland XR 26, but there are sufficient uncertainties for all total-body measurements during weight change to be treated with suspicion.  相似文献   
997.
Using any imaging modality, the elbow is a complex joint to evaluate. The use of scintigraphy in the evaluation of the effects of acute or chronic trauma has largely been confined to epicondylitis. We developed a skyline view of the elbow that minimized the effect of overlap and assessed its incremental value in the scintigraphic assessment of several pathological conditions. Thirty-four abnormalities were evaluated in 20 patients with a range of pathologies, including epicondylitis, ligamentous avulsion injury, articular injury, fractures and synovitis. The incremental value of addition of the skyline view to the standard views was assessed in addition to the overall accuracy of scintigraphy. Overall, scintigraphy detected 27 of 34 abnormalities, with the standard views of the elbow accurately identifying 15 and the skyline view 23 abnormalities. This gave the skyline view an incremental value of 24% over the standard views. In conclusion, scintigraphy has the potential to identify a greater range of pathologies in the elbow than previously reported, due to the addition of the skyline view to the standard views.  相似文献   
998.
999.
Surgical management of severe secondary peritonitis   总被引:5,自引:0,他引:5  
BACKGROUND: Despite advances in diagnosis, surgery, antimicrobial therapy and intensive care support, the mortality rate associated with severe secondary peritonitis remains unacceptably high. This article presents various surgical treatment strategies for severe secondary peritonitis, emphasizing the role of open management of the abdomen and planned relaparotomies. METHODS: Material was identified from previous review articles, references cited in original papers and a Medline search of the literature. RESULTS AND CONCLUSION: Surgical treatment of severe secondary peritonitis is highly demanding and very complex. The combination of improved surgical techniques, antimicrobial therapy and intensive care support has improved the outcome of such peritonitis following perforation or anastomotic disruption of the digestive tract, or infected necrotizing pancreatitis. However, aggressive surgical treatment strategies, such as open management of the abdomen and planned relaparotomies, may have reached their limits.  相似文献   
1000.
MR imaging of the male pelvis   总被引:2,自引:0,他引:2  
Prostate and urinary bladder cancer are the most frequently encountered malignancies of the urinary tract. Appropriate use of the different imaging techniques is crucial for accurate assessment of prognosis and for the development of appropriate treatment planning. Especially determination of local tumor extension and detection of nodal or bone metastases is extremely important. In this regard MR imaging is the most promising imaging technique. Therefore, in this review its role in staging these malignancies is evaluated and compared with clinical staging, and other imaging techniques. Finally, future developments, such as new sequences, new contrast agents, the role of surface coils and MR-guided biopsy, are considered. Also, the preferred radiological approach is discussed.  相似文献   
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