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11.
Methicillin-resistant Staphylococcus aureus (MRSA) is no longer only hospital acquired. MRSA is defined as community acquired if the MRSA-positive specimen was obtained outside hospital settings or within 2 days of hospital admission, and if it was from a person who had not been hospitalized within 2 years before the date of MRSA isolation. To estimate the proportion of community-acquired MRSA, we analyzed previous hospitalizations for all MRSA-positive persons in Finland from 1997 to 1999 by using data from the National Hospital Discharge Register. Of 526 MRSA-positive persons, 21% had community-acquired MRSA. Three MRSA strains identified by phage typing, pulsed-field gel electrophoresis, and ribotyping were associated with community acquisition. None of the strains were multiresistant, and all showed an mec hypervariable region hybridization pattern A (HVR type A). None of the epidemic multiresistant hospital strains were prevalent in nonhospitalized persons. Our population-based data suggest that community-acquired MRSA may also arise de novo, through horizontal acquisition of the mecA gene. 相似文献
12.
Annertz K Anderson H Biörklund A Möller T Kantola S Mork J Olsen JH Wennerberg J 《International journal of cancer. Journal international du cancer》2002,101(1):95-99
In several countries, increased incidence of squamous cell carcinoma (SCC) of the tongue in young adults has been suspected during the last decades. Some reports indicate a lower survival rate for young patients compared to older patients. In other reports, there has not been any considerable difference in survival when comparing young adults to older patients, whereas some authors have shown better survival for young adults. This disease is rare in young adults, and early reports were based on comparable small numbers and selected patients. Our aim was first to perform a population-based study to determine if an increased incidence in SCC of the tongue could be verified in a larger population comprising the Scandinavian countries Denmark, Finland, Sweden and Norway. A second aim was to determine survival rates for young adults compared to older patients. The material was based on the annual cancer incidence and survival reports from the Scandinavian cancer registries. The study period was 1960-1994. During that period, 5,024 SCCs of the tongue were reported. Of these, 276 (5.5%) were young adults (20-39 years). The incidence increased at all ages except for women 65-79 years old. The increase was most pronounced in young adults: 0.06-0.32 for men and 0.03-0.19 for women, counted by 100,000 person-years. Relative survival was significantly better for young adults compared to older patients. 相似文献
13.
Claus AM Totterman SM Sychterz CJ Tamez-Peña JG Looney RJ Engh CA 《Clinical orthopaedics and related research》2004,(422):167-174
To assess the accuracy of a computer-assisted computed tomography image analysis program in determining the location and volume of periacetabular osteolysis, we designed an osteolysis model by implanting bilateral total hip replacements in human pelvic cadavers and creating osteolytic lesions of varying sizes. The volumes of 48 defects were measured physically, and axial computed tomography scans were obtained. The computed tomography images were processed with streak artifact reduction and segmentation algorithms. The location and volume of lesions were determined from these images. Eighty-one percent (39 lesions) were identified correctly from the computed tomography scans. Detection was location-dependent. More lesions were detected in the ilium (100%) and at the rim (89%) than in the ischium (78%) or the pubis (50%). Computed tomography overestimated lesion volume by a mean of 0.5 +/- 2.3 cm. The volumetric error was unrelated to lesion location but was dependent on lesion size. As lesion size increased above 10 cm, the mean percentage error decreased to 1.8%. Computed tomography image analysis can be used more accurately than plain radiographs to investigate the effectiveness of treatment and the natural history of pelvic osteolysis. 相似文献
14.
15.
Accuracy and reproducibility of manual and semiautomated quantification of MS lesions by MRI 总被引:4,自引:0,他引:4
Ashton EA Takahashi C Berg MJ Goodman A Totterman S Ekholm S 《Journal of magnetic resonance imaging : JMRI》2003,17(3):300-308
PURPOSE: To evaluate the accuracy, reproducibility, and speed of two semiautomated methods for quantifying total white matter lesion burden in multiple sclerosis (MS) patients with respect to manual tracing and to other methods presented in recent literature. MATERIALS AND METHODS: Two methods involving the use of MRI for semiautomated quantification of total lesion burden in MS patients were examined. The first method, geometrically constrained region growth (GEORG), requires user specification of lesion location. The second technique, directed multispectral segmentation (DMSS), requires only the location of a single exemplar lesion. Test data sets included both clinical MS data and MS brain phantoms. RESULTS: The mean processing times were 60 minutes for manual tracing, 10 minutes for region growth, and 3 minutes for directed segmentation. Intra- and interoperator coefficients of variation (CVs) were 5.1% and 16.5% for manual tracing, 1.4% and 2.3% for region growth, and 1.5% and 5.2% for directed segmentation. The average deviations from manual tracing were 9% for region growth and 5.7% for directed segmentation. CONCLUSION: Both semiautomated methods were shown to have a significant advantage over manual tracing in terms of speed and precision. The accuracy of both methods was acceptable, given the high variability of the manual results. 相似文献
16.
Cheng ZJ Finckenberg P Louhelainen M Merasto S Tikkanen I Vapaatalo H Mervaala EM 《European journal of pharmacology》2003,461(2-3):159-169
The present study examined the role of cyclooxygenase-synthetized prostanoids in the pathogenesis of angiotensin-II-induced inflammatory response and vascular injury in transgenic rats harboring mouse renin-2 gene (mREN2 rats). Five- to six-week-old, heterozygous mREN2 rats received the following drug regimens for 8 weeks: (1) controls; (2) cyclooxygenase-2 inhibitor (MF-tricyclic [3-(3,4-difluorophenyl)-4-(4-(methylsulfonyl) phenyl)-2(5H)-furanone], 14 mg kg(-1) p.o.); (3) cyclooxygenase-1/cyclooxygenase-2 inhibitor (sulindac, 14 mg kg(-1) p.o.); (4) angiotensin II receptor antagonist (losartan 40 mg kg(-1) p.o.); (5) MF-tricyclic + losartan; (6) sulindac + losartan. Normotensive Sprague-Dawley rats served as controls. mREN2 rats developed pronounced hypertension, cardiac hypertrophy, and albuminuria as compared to normotensive Sprague-Dawley controls. mREN2 rats showed pronounced perivascular inflammation and morphological damage in the kidneys and the heart. Both MF-tricyclic and sulindac further increased blood pressure and albuminuria in mREN2 rats. Neither MF-tricyclic nor sulindac were able to prevent angiotensin-II-induced perivascular inflammation and morphological changes in the heart or in the kidneys. Myocardial and renal cyclooxygenase-2 mRNA expressions were decreased in mREN2 rats, whereas no difference was found in cyclooxygenase-1 mRNA expressions. Sulindac increased both cyclooxygenase-1 and cyclooxygenase-2 gene expressions, whereas MF-tricyclic increased only cyclooxygenase-2 gene expressions. Losartan normalized blood pressure, cardiac hypertrophy, albuminuria, inflammatory response and morphological changes in mREN2 rats, both in the presence and absence of cyclooxygenase inhibitors. Our findings indicate that cyclooxygenase does not play a central role in the pathogenesis of angiotensin-II-induced inflammatory response and vascular injury in mREN2 rats. 相似文献
17.
18.
Ibrahem S Salmenlinna S Virolainen A Kerttula AM Lyytikäinen O Jägerroos H Broas M Vuopio-Varkila J 《Journal of clinical microbiology》2009,47(1):32-37
Following an outbreak caused by staphylococcal cassette chromosome mec (SCCmec) type V methicillin (meticillin)-resistant Staphylococcus aureus (MRSA), a point-prevalence survey of the nasal carriage of staphylococci was conducted in a long-term-care facility in northern Finland in 2004. The focus was directed at methicillin-resistant coagulase-negative staphylococci (MR-CNS) and their SCCmec elements. A nasal swab was taken from 76 of the 80 residents 6 months after the onset of the outbreak. Staphylococcal isolates were identified by conventional methods and the GenoType Staphylococcus test, and their SCCmec elements were analyzed. Of the 76 individuals, 24 (32%) carried S. aureus and 67 (88%) CNS in their nostrils. Of the CNS carriers, 41 (61%) had at least one mecA-positive MR-CNS, and two individuals (3%) had both MRSA and methicillin-resistant Staphylococcus epidermidis (MRSE). Among the 61 MR-CNS isolates identified, 49 (80%) were MRSE. The distribution of the SCCmec types was diverse: 20 (33%) were of type IV, 11 (18%) of type V, 4 (6%) of type I or IA, 3 (4%) of type II, and 23 (38%) of new types (with six different combinations of ccr and other mec genes or only mecA). Both of the individuals with MRSA and MRSE shared SCCmec type V among their isolates. Nasal MR-CNS carriage was common among the residents of this long-term-care facility. A variety of SCCmec types, including many new types, were identified among the MR-CNS strains. The horizontal transfer of SCCmec elements is speculated based on the sharing of SCCmec type V between MRSA and MRSE. 相似文献
19.
Esophageal atresia (EA) affects one in 2,840 newborns, and over half have associated anomalies that typically affect the midline.
After EA repair in infancy, gastroesophageal reflux (GER) and esophageal dysmotility and respiratory problems are common.
Significant esophageal morbidity associated with EA extends into adulthood. Surgical complications, increasing age, and impaired
esophageal motility predict the development of epithelial metaplasia after repair of EA. To date, worldwide, six cases of
esophageal cancer have been reported in young adults treated for EA. According to our data, the statistical risk for esophageal
cancer is not higher than 500-fold that of the general population. However, the overall cancer incidence among adults with
repaired EA does not differ from that of the general population. Adults with repaired EA have had significantly more respiratory
symptoms and infections, as well as more asthma and allergies than does the general population. Nearly half the patients have
bronchial hyperresponsiveness. Thoracotomy-induced rib fusion and gastroesophageal reflux-associated columnar epithelial metaplasia
are the most significant risk factors for the restrictive ventilatory defect that occurs in over half the patients. Over half
the patients with repaired EA are likely to develop scoliosis. Risk for scoliosis is 13-fold after repair of EA in relation
to that of the general population. Nearly half of the patients have had vertebral anomalies predominating in the cervical
spine, and of these, most were vertebral fusions. The natural history of spinal deformities seems, however, rather benign,
with spinal surgery rarely indicated. 相似文献
20.