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101.
Arthroscopic abrasion arthroplasty, subchondral drilling, and microfracture continue to be performed with some frequency in younger patients with focal chondral defects and occasionally for patients with moderate degenerative knee arthritis. The plain radiographic appearance after those procedures may mimic avascular necrosis, but MRI is a sensitive method used to exclude the diagnosis of avascular necrosis and evaluate the extent to which fibrocartilaginous repair tissue has formed. When combined with an appropriate clinical history, dedicated articular cartilage imaging sequences improve the sensitivity and specificity that MRI provides in these patients with chondral knee injuries. 相似文献
102.
Saidon J He J Zhu Q Safavi K Spångberg LS 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2003,95(4):483-489
OBJECTIVE: Mineral trioxide aggregate (MTA) is being widely used for root-end fillings, pulp capping, perforation repairs, and other endodontic procedures. MTA and Portland cement (PC) have many similar physical, chemical, and biologic properties. PC cement has shown promising potential as an endodontic material in several studies in vitro and in vivo. The purpose of this study was to compare the cytotoxic effect in vitro and the tissue reaction of MTA and Portland cement in bone implantation in the mandibles of guinea pigs. STUDY DESIGN: Millipore culture plate inserts with freshly mixed or set material were placed into the culture plates with already attached L929 cells. After an incubation period of 3 days, the cell morphology and cell counts were studied. Adult male guinea pigs under strict asepsis were anesthetized, during which a submandibular incision was made to expose the symphysis of the mandible. Bilateral bone cavities were prepared and Teflon applicators with freshly mixed materials were inserted into the bone cavities. Each animal received 2 implants, one filled with ProRoot and 1 with PC. The animals were killed after 2 or 12 weeks, and the tissues were processed for histologic evaluation by means of light microscopy. RESULTS: There was no difference in cell reactions in vitro. Bone healing and minimal inflammatory response adjacent to ProRoot and PC implants were observed in both experimental periods, suggesting that both materials are well tolerated. CONCLUSIONS: MTA and PC show comparative biocompatibility when evaluated in vitro and in vivo. The results suggest that PC has the potential to be used as a less expensive root-end filling material. 相似文献
103.
Boshtam M Rafiei M Sadeghi K Sarraf-Zadegan N 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2002,72(5):309-314
This triple-blind placebo-controlled clinical trial was performed to determine the effects of the anti-oxidant vitamin E on blood pressure and heart rate in patients with mild hypertension. A total of 70 new mild hypertensive subjects (systolic blood pressure, SBP: 140-160 mmHg; diastolic blood pressure, DBP: 90-100 mmHg) without secondary hypertension were selected from among people referred to the Hypertension Unit of Isfahan Cardiovascular Research Center and divided randomly into two groups of drug (DG) and placebo (PG). All subjects were aged from 20 to 60 years old, without any other cardiovascular risk factors. The drug group received vitamin E tablets (200 IU/day) and the placebo group received placebo only for 27 weeks. At the beginning and the end of the study, the blood vitamin E level was measured fluorimetrically in all subjects according to the Hansen and Warwick method [14, 15]. Blood pressure and heart rate were measured at the beginning, during, and at the end of the study. Blood pressure was measured by a physician using one random zero mercury sphygmomanometer. Personal information and dietary habits of subjects were collected by separate questionnaire. At the end of the study, it was found that the vitamin E supplement had caused a remarkable decrease in SBP (-24% in DG versus -1.6% in PG) and a less remarkable decrease in DBP (-12.5% in DG versus -6.2% in PG) (p < 0.05). The change in heart rate was -4.3% in DG, and -14.0% in PG (p < 0.05). It is concluded that a vitamin E supplement of 200 IU/day can be effective in mild hypertensive patients in the long term, probably due to nitric oxide, and improve their blood pressure status. Therefore, vitamin E supplement could be recommended to such patients. 相似文献
104.
DeLisi LE Shaw SH Crow TJ Shields G Smith AB Larach VW Wellman N Loftus J Nanthakumar B Razi K Stewart J Comazzi M Vita A Heffner T Sherrington R 《The American journal of psychiatry》2002,159(5):803-812
OBJECTIVE: Some genome-wide scans and association studies for schizophrenia susceptibility genes have yielded significant positive findings, but there is disagreement between studies on their locations, and no mutation has yet been found in any gene. Since schizophrenia is a complex disorder, a study with sufficient power to detect a locus with a small or moderate gene effect is necessary. METHOD: In a genome-wide scan of 382 sibling pairs with a diagnosis of schizophrenia or schizoaffective disorder, 396 highly polymorphic markers spaced approximately 10 centimorgans apart throughout the genome were genotyped in all individuals. Multipoint nonparametric linkage analysis was performed to evaluate regions of the genome demonstrating increased allele sharing, as measured by a lod score. RESULTS: Two regions with multipoint maximum lod scores suggesting linkage were found. The highest lod scores occurred on chromosome 10p15-p13 (peak lod score of 3.60 at marker D10S189) and the centromeric region of chromosome 2 (peak lod score of 2.99 at marker D2S139). In addition, a maximum lod score of 2.00 was observed with marker D22S283 on chromosome 22q12, which showed evidence of an imprinting effect, whereby an excess sharing of maternal, but not paternal, alleles was present. No evidence of linkage was obtained at several locations identified in previous studies, including chromosomes 1q, 4p, 5p-q, 6p, 8p, 13q, 15p, and 18p. CONCLUSIONS: The findings of this large genome-wide scan emphasize the weakness and fragility of linkage reports on schizophrenia. No linkage appears to be consistently replicable across large studies. Thus, it has to be questioned whether the genetic contribution to this disorder is detectable by these strategies and the possibility raised that it may be epigenetic, i.e., related to gene expression rather than sequence variation. Nevertheless, the positive findings on chromosome 2, 10, and 22 should be pursued further. 相似文献
105.
CT-guided percutaneous fine-needle aspiration biopsy of small (< or =1-cm) pulmonary lesions 总被引:3,自引:0,他引:3
Wallace MJ Krishnamurthy S Broemeling LD Gupta S Ahrar K Morello FA Hicks ME 《Radiology》2002,225(3):823-828
PURPOSE: To determine the accuracy of percutaneous computed tomography (CT)-guided fine-needle aspiration biopsy (FNAB) of small (< or =1.0-cm in diameter) pulmonary lesions. MATERIALS AND METHODS: Sixty-one patients (34 men and 27 women) 21-89 years old (mean age, 61.3 years) with lung nodules 1.0 cm or smaller underwent CT-guided transthoracic FNAB. Fifty-seven of the 61 patients had an underlying primary malignancy. Maximum nodule diameters were 0.5-0.7 cm in 10 patients and 0.8-1.0 cm in 51 patients. Cytopathologic evaluation of FNAB samples was immediate in all patients. Sensitivity and accuracy were calculated, and each case was reviewed for complications, including pneumothorax and thoracostomy tube insertion. Four patients were not included in our statistical analysis because of a lack of follow-up information. RESULTS: FNAB samples were adequate for diagnosis in 47 (77%) of 61 patients. Diagnoses were malignancy (n = 29) or suspected malignancy (n = 3) in 52% (n = 32) and benign or atypical findings in 25% (n = 15). Findings were nondiagnostic in 23% (n = 14). Of the 29 patients without evidence of malignancy, 25 had follow-up findings available. Follow-up included chest CT in 16 patients and surgical resection in nine. Four patients were not included in statistical analysis because of a lack of follow-up information. Overall sensitivity was 82% (32 of 39); specificity, 100% (18 of 18); and diagnostic accuracy, 88% (50 of 57) on the basis of 57 patients being evaluable. Results for 47 0.8-1.0-cm lesions were considerably better (sensitivity, 88%; accuracy, 92%) than those for 10 0.5-0.7-cm lesions (sensitivity, 50%; accuracy, 70%). Sensitivity (75% vs 87%) and accuracy (87% vs 89%) also improved when comparing subpleural (< or =1.0 cm from pleural surface, n = 30) with deeper (>1 cm from pleural surface, n = 27) pulmonary lesions, but the improvement did not indicate statistical significance. Core biopsy did not reveal malignancy in any of the nine patients in whom preliminary cytologic results were inconclusive and did not improve diagnostic yield. Thirty-eight (62%) patients had pneumothorax, with 19 (31%) requiring thoracostomy tube placement. CONCLUSION: CT-guided FNAB of pulmonary lesions 1.0 cm or smaller can yield high diagnostic accuracy rates approaching those of larger lesions; FNAB of 0.8-1.0-cm lesions that are not subpleural offers the best opportunity for success. 相似文献
106.
Anne McTiernan Yutaka Yasui Bess Sorensen Melinda L Irwin Angela Morgan Rebecca E Rudolph Christina Surawicz Johanna W Lampe Kamran Ayub John D Potter Paul D Lampe 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1588-1597
BACKGROUND: Colon crypt architecture and proliferation may be appropriate biomarkers for testing prevention interventions. A hypothesized mechanism for exercise-induced colon cancer risk reduction might be through alterations in colon crypt cell architecture and proliferation. METHODS: Healthy, sedentary participants with a colonoscopy within the previous 3 years were recruited through gastroenterology practices and media. We randomly assigned 100 women and 102 men, ages 40 to 75 years, to a control group or a 12-month exercise intervention of moderate-to-vigorous aerobic exercise, 60 minutes per day, 6 days per week, and assessed change in number and relative position of Ki67-stained cells in colon mucosal crypts. RESULTS: Exercisers did a mean 370 min/wk (men) and 295 min/wk (women) of exercise (seven dropped the intervention). In men, the mean height of Ki67-positive nuclei relative to total crypt height was related to amount of exercise, with changes from baseline of 0.0% (controls), +0.3% (exercisers <250 min/wk), -1.7% (exercisers 250-300 min/wk), and -2.4% (exercisers >300 min/wk; P(trend) = 0.03). In male exercisers whose cardiopulmonary fitness (V(O(2))max) increased >5%, the mean height of Ki67-positive nuclei decreased by 2% versus 0.9% in other exercisers, and versus no change in controls (P(trend) = 0.05). Similar trends were observed in other proliferation markers. In women, increased amount of exercise or V(O(2))max did not result in notable changes in proliferation markers. CONCLUSIONS: A 12-month moderate-to-vigorous intensity aerobic exercise intervention resulted in significant decreases in colon crypt cell proliferation indices in men who exercised a mean of >/=250 min/wk or whose V(O(2))max increased by >/=5%. 相似文献
107.
M. Erol Demirseren Kamran Afandiyev Mustafa Durgun Ergin Seven Olcay Belenli 《European archives of oto-rhino-laryngology》2008,265(6):639-641
Definition of malformations of the tragus is important for terminology and treatment. Most common entities are the skin tag,
accessory tragus, preauricular sinus, and cyst, whereas macrotragus is an uncommon and unaddressed deformity that should be
distinguished from these. In this report, three cases with diagnosis of the macrotragus are presented. The tragus was uniformly
large and displaced anteriorly, and external auditory meatus was not obliterated in all cases. For correction, excision of
the excess tragal cartilage and skin was performed. In all cases, bilaterally symmetric tragus was achieved. There were no
complications in the early postoperative period and there was no enlargement after 6 months of observation. Macrotragus and
accessory tragus are different entities that should be distinguished for accurate diagnosis. They have similar histopathological
but distinct anatomical characteristics. Although both are treated by a simple excision, in the case of macrotragus, special
effort should be taken to leave enough cartilage to restore normal tragal contours.
Presented at the 5th Congress of the Balkan Association for Plastic, Reconstructive Aesthetic Surgery, Kuşadası, Turkey, May
22–26, 2007. 相似文献
108.
Kamran Abbasi 《British medical journal》1998,316(7131):637
109.
110.
The association between supracondylar-intercondylar distal femoral fractures and coronal plane fractures 总被引:2,自引:0,他引:2
Nork SE Segina DN Aflatoon K Barei DP Henley MB Holt S Benirschke SK 《The Journal of bone and joint surgery. American volume》2005,87(3):564-569
BACKGROUND: Isolated coronal plane fractures of the distal femoral condyles (Hoffa fractures) occur uncommonly, are difficult to diagnose, and may be challenging to treat. The combination of supracondylar distal femoral fractures and these coronal plane fractures is thought to occur rarely. The purposes of the present study were to identify the frequency of the association between supracondylar-intercondylar distal femoral fractures and coronal fractures of the femoral condyle and to describe the radiographic evaluation of these injuries. METHODS: One hundred and eighty-nine patients with 202 supracondylar-intercondylar distal femoral fractures were retrospectively evaluated clinically and radiographically. RESULTS: Coronal plane fractures were diagnosed in association with seventy-seven (38.1%) of the 202 supracondylar-intercondylar distal femoral fractures. Fifty-nine (76.6%) of these coronal fractures involved a single condyle, and eighteen involved both the medial and lateral femoral condyles. Eighty-five percent of the coronal fractures involving a single condyle were located laterally. Patients with an open distal femoral fracture were 2.8 times more likely to have a coronal plane fracture than patients with a closed fracture were (95% confidence interval, 1.54 to 5.25). Coronal plane fractures were diagnosed in 47% of the 102 knees that were evaluated with computerized tomography, compared with 29% of the 100 knees that were not (p = 0.008). Ten coronal plane fractures that had been unrecognized preoperatively were identified only at the time of operative fixation of the distal femoral fracture; none of these fractures occurred in patients who had been evaluated with computerized tomographic scanning preoperatively. CONCLUSIONS: Coronal plane fractures frequently occurred in association with high-energy supracondylar-intercondylar distal femoral fractures; in the present study, the prevalence of associated coronal plane fractures was 38%. The lateral condyle was involved more frequently than the medial condyle was. Coronal plane fractures of both condyles were observed commonly, and the majority of coronal plane fractures were associated with open wounds. Since the surgical tactic for the treatment of a supracondylar-intercondylar distal femoral fracture may be altered by the additional diagnosis of a coronal plane fracture component, preoperative computerized tomographic scanning of the injured distal part of the femur, particularly when there is an associated open wound, is strongly recommended. 相似文献