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991.
Suriani R Venturini I Taraglio S Mazzucco D Grosso S Predebon S Mamo C Tremosini S Ballesini P Borghi A Zeneroli ML 《Hepato-gastroenterology》2005,52(61):285-288
BACKGROUND/AIMS: To evaluate the utility of 2 biopsies of antrum and gastric body on routine endoscopy for the assessment of type III intestinal metaplasia (IM-3) and Helicobacter pylori (Hp), 1750 patients (pts) (895 males; 855 females) were considered from June'98 to June'00. METHODOLOGY: Specimens were graded 0 to 3 for atrophy, IM-3 and Hp. 610 pts treated previously with antibiotics or not eligible for biopsy were excluded from initial 2360 pts. RESULTS: IM-3 was found in 118 pts (6.7%), 100 pts (5.7%) only in the antrum. 10 of 355 pts (2.8%) with normal endoscopy and 47 of 702 (6.6%) with non-erosive endoscopic gastritis resulted IM-3 positive in the antrum. 709 pts (40.5%) were positive for Hp in antrum and/or corpus. The presence of Hp and IM-3 in the antrum was not correlated (p=0.99; Spearman test). A positive correlation (p=0.000) between duodenal ulcer and Hp was found when antral Hp positivity was taken into account. The gastric carcinoma risk index (GCRI) was found in 358 pts (20.4%); in this group 131 pts (36.6%) were Hp positive, 81 pts (22.65%) had IM-3 only in the antrum, 184 pts (51.4%) had atrophy. CONCLUSIONS: The incidence of IM-3 is low (6.7%) in routine endoscopy. Normal endoscopy doesn't exclude the presence of IM-3. Biopsy is necessary to discover IM-3 in the antrum in 5.3% of pts with normal or aspecific endoscopic gastritis. Application of the GCRI might be useful for identifying a group of patients carrying a higher risk for gastric carcinoma. 相似文献
992.
Lobo RD Levin AS Gomes LM Cursino R Park M Figueiredo VB Taniguchi L Polido CG Costa SF 《American journal of infection control》2005,33(2):83-87
BACKGROUND: Central venous catheter-associated bloodstream infections (CVC-BSI) are a frequent cause of morbidity and mortality in intensive care settings. Many strategies have been used to decrease the risk of CVC-BSI; however, few studies have explored the educational intervention as an approach to reduce the CVC-BSI rates. OBJECTIVE: The purpose of this study was to determine the impact of an educational program targeted to specific points observed during CVC care practices on decreasing CVC-BSI in a medical intensive care unit. METHODS: An educational program was developed by a multidisciplinary task force to highlight correct practices for CVC care. Relative risk ratios, 95% confidence intervals, and P values were determined for all primary and secondary outcomes. The chi 2 linear test for trends of CVC-BSI rates was performed during the study period and the following year. RESULTS: Forty-eight primary bloodstream infections occurred in 2450 catheter-days (20 per 1000 catheter-days) in the 16 months before the intervention. After the educational intervention and policy changes such as standardized povidone-iodine use during dressing care, the number of CVC-BSI dropped to 16 in 1381 catheter-days (11 per 1000 catheter-days), a decrease of 40%. The rate of CVC-BSI remained almost the same, 22 in 1701 catheter-days (12 per 1000 catheter-days), during the following year after the educational intervention (P = .07). The distribution of pathogens was different comparing the pre- and postintervention period. Staphylococcus aureus was the most common pathogen in preintervention, decreasing significantly during the study period (P = .02). The adhesion to the overall catheter care policy improved significantly in the postintervention period (P < .01). CONCLUSION: A multiple approach included an educational strategy, targeted to specific problems observed during a careful evaluation of CVC care practices, and policy changes can decrease rates of CVC-BSI. However, despite the good results, our rates are still high, and reinforcement of CVC care practices will be continued. 相似文献
993.
Negredo E Martínez-López E Paredes R Rosales J Pérez-Alvarez N Holgado S Gel S del Rio L Tena X Rey-Joly C Clotet B 《AIDS (London, England)》2005,19(3):343-345
HIV-1-infected patients with osteoporosis were randomly assigned to alendronate 70 mg once-weekly plus dietary counselling (n = 11) or diet counselling alone (n = 14). At week 96, 27% of patients on alendronate versus 96% of controls presented with osteoporosis. Spine bone mineral density (BMD) increases were detected at week 48, and progressed thereafter. Improvements in trochanter BMD were obtained after 2 years. Once-weekly oral alendronate may be an effective and safe treatment for HIV-1-associated osteoporosis. 相似文献
994.
995.
Potential of dose reduction after marker placement with full-field digital mammography 总被引:1,自引:0,他引:1
Riedl CC Jaromi S Floery D Pfarl G Fuchsjaeger MH Helbich TH 《Investigative radiology》2005,40(6):343-348
OBJECTIVES: The purpose of our study was to assess the potential for radiation dose reduction in digital postinterventional digital mammograms after marker placement. MATERIALS AND METHODS: One hundred consecutive cases of marker placement (hook-wire localization or postbiopsy clip marker placement), with 200 full-field digital baseline mammograms (craniocaudal and mediolateral), were included in this prospective trial. For the postinterventional digital mammograms, the milliampere seconds were reduced either by 50% or by 75%. Dose-reduced images were evaluated for sufficient image quality to verify the position of the marker. RESULTS: In 193 of 200 cases (96.5%), image quality was sufficient to verify the correct position of the marker. One (1%) case with insufficient image quality occurred in the 50% dose-reduction group and 6 (6%) in the 75% dose-reduction group (P = 0.06). CONCLUSION: Our results indicate that under evaluation of each individual case, a dose reduction of 50% to 75% can be recommended in postinterventional digital mammograms. 相似文献
996.
Elastosonography in the diagnosis of the nodular breast lesions: preliminary report 总被引:13,自引:0,他引:13
PURPOSE: To assess the diagnostic accuracy of elastography in characterising nodular breast lesions. MATERIALS AND METHODS: A total of 82 patients who received mammographic, ultrasonographic and elastographic evaluation in a single session at two Italian centres (Dept of Radiology, Az. Ospedali Riuniti, Ancona, and Ospedale Valduce, Como, Italy) between January and August 2004 according to identical protocols exhibited 91 nodules that were subjected to cytological/histological examination. Lesions were classified and scored and the sensitivity and specificity of elastography calculated. RESULTS: Overall sensitivity and specificity were 79% and 89%, respectively. However, sensitivity was 86% and 65% and specificity 100% and 62% for lesions < 2 cm and > 2 cm in diameter, respectively. Despite the small sample and the fact that it does not include the full range of cell types, tumour cell composition seemed to affect accuracy. CONCLUSIONS: Elastography is easy and rapid to perform. Larger studies are needed to establish semiological patterns; despite the small patient sample, these data provide an interesting contribution. 相似文献
997.
Cardinale L Cortese G Borasio P Dogliotti L Ferraris F Novello S Perotto F Scagliotti G Fava C 《La Radiologia medica》2005,110(5-6):532-543
PURPOSE: Lung cancer has a high mortality rate and its prognosis largely depends on early detection. We report the prevalence data of the study on early detection of lung cancer with low-dose spiral CT underway at our hospital. MATERIALS AND METHODS: Since the beginning of 2001, 519 asymptomatic volunteers have undergone annual blood tests, sputum tests, urinalyses and low-dose spiral CT. The inclusion criteria were age (=/> 55 years old), a history of cigarette smoking and a negative history for previous neoplastic disease. The diagnostic workup varied depending on the size and CT features of the nodules detected. RESULTS: At baseline, the CT scan detected nodules > 5 mm in 22% of subjects; the nodules were single in 42 and multiple in 71. In 53% of cases the findings were completely negative, while in 122 (23.4%) nodules with a diameter < 5 mm were detected. Six cases of lung cancer were identified, of which four were stage I, one stage was IIIB and one was stage IV with adrenal metastases. CONCLUSIONS: Our preliminary data on spiral CT as a potential new diagnostic tool for lung cancer screening, although less promising than the Japanese and ELCAP results, confirm the feasibility of the technique. Additional validation is, however, required. 相似文献
998.
Rivolta A Emanuelli S Tessarin C Bresciani S Genovese MG Rogge D Scielzo G 《La Radiologia medica》2005,110(5-6):689-698
PURPOSE: The aim of this study was to evaluate the effective dose in interventional radiology and angiography procedures on the basis of the dose-area product (DAP), either measured or calculated using two different methods. MATERIALS AND METHODS: We studied 2072 examinations carried out on several X-ray systems both in angiography and in interventional radiology. Some of the systems were equipped with an on-board transmission chamber for DAP measurements; for these systems we took direct DAP measurements for each type of examination. For the systems without the dose measurement device, we used a portable transmission chamber, acquiring the data from a set of sampling frames. We then derived the dose values from the systems' dosimetry data and the information about each examination. To this end, the dosimetry of each x-ray system was done by measuring tube output in the different acquisition modes, backscatter factor and field-homogeneity factor. Survey data sheets were filled in after every examination indicating the exposure data (mean Kv, mAs, focus-skin distance and field size). These values combined with the dosimetric data were used to evaluate the DAP for each exam. Where possible, we compared the measured and calculated DAP values by assessing the percentage deviation between each pair of values. A similar comparison was made for the single examinations using a simplified calculation algorithm reported in the literature. For all the examinations for which we had adequate survey data sheets, we estimated the DAP and the entrance dose values and, with the aid of WinODS software, the effective dose. RESULTS: The direct measurements of DAP showed that, in interventional radiology and angiographic procedures, the variability in examination conditions leads to a wide range of possible patient doses even within the same examination type.The comparison between the measured and calculated DAP using our algorithm showed substantial agreement (mean difference 30%, maximum 80%). By contrast, using the algorithm proposed in the literature, we obtained deviations higher than 100%.An estimate of the effective dose for all the recorded examinations (2072) permitted evaluation of both magnitude and variability of patient doses in special radiology procedures such as angiography and interventional radiology. However, it should be noted that evaluations based on calculated DAP values may be as uncertain as those estimated for DAP, and that clearly the evaluations made for the examinations for which direct measurements are available are more accurate.In particularly 'invasive' examinations in terms of entrance dose, where the threshold limits for deterministic effects might possibly be exceeded, the equivalent doses to critical organs were also assessed. This analysis showed that in a small percentage of patients (5%) 2 Gy to the skin was exceeded in the areas exposed with possible transient erythema, while in fewer than 2% of patients, the 3 Gy limit for temporary epilation was exceeded. CONCLUSIONS: Many interventional radiology, especially haemodynamic, examinations have shown to give significant exposure to patients. The direct dose measurement method has shown to be the only method able to provide reliable information on such exposure.However, the authors believe that since the patient dose cannot be established in advance, even in terms of magnitude and since direct dose measurement cannot be performed on all patients, it is nonetheless interesting to be able to assess, at least semiqualitatively, the amount of the above doses. 相似文献
999.
Brenière SF Pietrokovsky S Gastélum EM Bosseno MF Soto MM Ouaissi A Kasten FL Wisnivesky-Colli C 《Journal of medical entomology》2004,41(6):1015-1020
We analyzed triatomine blood feeding patterns to evaluate the role of peridomiciles in Trypanosoma cruzi transmission at the rural village of Tepehuaje de Morelos at Jalisco State, Mexico (1999). A total of 206 bugs were collected in 11 out of 26 households (42.3%). Nymphs predominated in the collections (64.9% of the total). Except for one Triatoma barberi female, a species that belongs to the protracta species complex, all adults were Triatoma longipennis, a species of the phyllosoma complex. Triatomines were exclusively present in peridomestic sites mainly piles of tiles and bricks, and none were found indoors. Overall infection rate was 56.6% and no significant differences (P > 0.05) were observed between nymphs and adults or males and females. Identified blood meals were chicken (29.4%), opossum (20.9%), pig (24.5%), murid (20.9%), dog (3.5%), and armadillo (0.7%). No gut content reacted against anti-human, anti-bovine, anti-rabbit, and anti-cat sera. In contrast to fifth nymphs and adults, 87% of the small nymphs fed on one host, indicating that they are less mobile than other stages. Most fifth nymphs and adults fed on domestic hosts, while small nymphs mainly fed on opossum and murid. Infection blood-meal indexes were around 50% for single meals on opossum and murid, stressing their importance as trypanosome donors. Peridomiciles in Tepehuaje could be regarded as interaction sites among domestic and wild and synanthropic mammals and triatomines, which would facilitate circulation of the same T. cruzi strains between domestic and sylvatic cycles. Stone-made walls and building materials, which hold synanthropic rodents and opossums, should be considered as targets for vector control measures. 相似文献
1000.
Vertical forces in labial and lingual orthodontics applied on maxillary incisors--a theoretical approach 总被引:3,自引:0,他引:3
Theoretical and experimental biomechanical analyses explain most labial orthodontics (LaO); however, lingual orthodontic (LiO) biomechanical principles are rarely introduced. The objective of this study was to apply basic biomechanical considerations in understanding the influence of maxillary incisor inclination and to compare the effect of labial vs lingual intrusive/extrusive forces on tooth movement. Basic anatomic and geometric hypotheses were assumed, ie, tooth length (crown and root), location of the center of resistance, and crown thickness. Incisor inclination as related to a perpendicular line to the occlusal plane (OP) varied between -35 degrees (retroclination) and 45 degrees (proclination). A 0 degrees inclination was defined as a tooth position with its long axis perpendicular to the OP. The buccolingual moment for characterizing root movement was calculated for an applied force perpendicular to the OP. The results showed that when using LaO, an extrusion force resulted in labial root movement from a retroclination of 20 degrees up to a proclination of 45 degrees. In LiO, labial root movement occurred only when the tooth was proclined more than 20 degrees. In all other tooth inclinations, lingual root movement occurred. The opposite tooth movement occurred when an intrusive force was applied. Application of a vertical force has different clinical effects on tooth movement with labial and lingual appliances. Application of a lingual force is more complicated, and its effect on tooth movement depends on bracket position and initial tooth inclination. 相似文献