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41.
Introduction Excision followed by RFA (eRFA) may allow improved cosmesis while ensuring negative margins in patients with breast cancer. This technique utilizes heat to create an additional tumor-free zone around the lumpectomy cavity. We hypothesized that eRFA will decrease the need for re-excision of inadequate margins.Methods Between July 2002 and January 2005, we conducted a multiphase trial of RFA of prophylactic mastectomy specimens and of women desiring lumpectomy. In both models, a lumpectomy was performed, the RFA probe was deployed 1 cm circumferentially into the walls of the lumpectomy cavity and maintained at 100°C for 15 min. Whole mount slides were used to measure the zone of ablation for ex vivo specimens. Hematoxylin and eosin staining of in vivo lumpectomy margins <3 mm was considered inadequate.Results Nineteen prophylactic mastectomy ablations revealed a consistent perimeter of ablation. Forty-one patients (mean age 63 ± 14 years) had an average tumor size of 1.6 ± 1.5 cm underwent in vivo eRFA, and 25% had inadequate margins: one focally positive, one <2 mm, eight <1 mm and one grossly positive. Only the grossly positive margin was re-excised. Overall complication rate of in vivo ablations was 7.5%. Twenty-four of 41 patients did not have post-eRFA XRT. No in-site local recurrences have occurred during a median follow-up of 24 months (12–45 months). Two patients have occurred elsewhere.Conclusions The ex vivo ablation model reliably created a 5–10 mm perimeter of ablation. In vivo, this zone reduced the need for re-excision for inadequate margins by 91% (10/11). Short-term follow-up suggests that eRFA could reduce re-excision surgery and local recurrence.  相似文献   
42.
Authentication and key agreement schemes play a very important role in enhancing the level of security of telecare medicine information systems (TMISs). Recently, Amin and Biswas demonstrated that the authentication scheme proposed by Giri et al. is vulnerable to off-line password guessing attacks and privileged insider attacks and also does not provide user anonymity. They also proposed an improved authentication scheme, claiming that it resists various security attacks. However, this paper demonstrates that Amin and Biswas’s scheme is defenseless against off-line password guessing attacks and replay attacks and also does not provide perfect forward secrecy. This paper also shows that Giri et al.’s scheme not only suffers from the weaknesses pointed out by Amin and Biswas, but it also is vulnerable to replay attacks and does not provide perfect forward secrecy. Moreover, this paper proposes a novel authentication and key agreement scheme to overcome the mentioned weaknesses. Security and performance analyses show that the proposed scheme not only overcomes the mentioned security weaknesses, but also is more efficient than the previous schemes.  相似文献   
43.
Treatment of metronidazole-resistant Trichomonas vaginalis infection is complicated by the lack of an effective alternative therapeutic regimen. Data on the susceptibility of the organism to metronidazole and other nitroimidazoles are important in managing intractable cases. A case of trichomonal vaginitis with true resistance to metronidazole that responded to treatment with tinidazole is reported.  相似文献   
44.
PURPOSE: To describe the clinical spectrum and severity of eye injuries sustained during the Persian Wednesday Eve Festival "Charshanbe-Soori" and to identify the fireworks devices involved. METHODS: Prospectively, consecutive patients treated for fireworks-related eye injuries in the emergency room at Farabi Eye Hospital, Tehran, over 3 days around the occasion in 2000, 2001, and 2002 were studied. RESULTS: Four hundred thirty-seven cases of eye injuries with an age range of 2-74 (median 17; SD 11.1) years were studied: 84.6% were male; 18.6% of the injuries were bilateral; 79.9% of the injured were bystanders or passersby. Eleven types of devices were involved, of which seven were explosives and eight were homemade. "Narenjaks," homemade grenades, were involved in 62.2%, firecrackers in 14.8%, and sparklers in 6.2% of the events. Injuries were categorized as severe in 49% of cases, and 45 (10.4%) people were hospitalized. Five eyes with no light perception and/or enucleation, 33 cases of monocular blindness, 54 (12.3%) cases of open globe (including intraocular foreign bodies) were observed. Grenades, bystander and passerby roles, outdoor context, a relatively older age, lower socioeconomic status, and male gender in the subset of passive roles were the determinants of more severe injuries (all p values < 0.05). Lid injuries (67.7%), corneal abrasions (51.6%), hyphema (48.1%), superficial foreign bodies (32.5%), and corneal contusions (13.8%) were the five leading injuries. CONCLUSIONS: In Iran, fireworks cause frequent and diverse injuries during the Wednesday Eve Festival and are a leading cause of severe eye injuries and monocular blindness.  相似文献   
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46.

Background

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.

Aim of the work

To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.

Patients and methods

26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.

Results

All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.

Conclusion

Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings.  相似文献   
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49.
Palindromic rheumatism: a response to chloroquine   总被引:3,自引:0,他引:3  
We reviewed 71 patients with palindromic rheumatism. The average length of followup was 3.6 years. Fifty-one patients received antimalarial therapy. Forty-one of the 51 patients experienced marked improvement with 77.5% reduction in frequency and 63% reduction in duration of attacks. Sixteen out of the 71 patients developed persistent arthritis in the form of rheumatoid arthritis (12 patients), systemic lupus erythematosus (2 patients), Crohn's disease (1 patient) and asymmetric seronegative arthropathy (1 patient). Chloroquine therapy, therefore, seems effective in relieving palindromic rheumatism.  相似文献   
50.
Fungal diversity in the Hyrcanian forests can greatly vary due to diverse ecological conditions. The scope of the present research was to investigate the diversity of wood decay fungi at three sites in the northern forests of Iran. Fruiting bodies of fungi were collected in three plots dominated by Quercus castaneifolia C.A.M. (oak) and Carpinus betulus L. (hornbeam) in the Hyrcanian Forest. As many as 19 and 13 taxa were found on hornbeam and oak, respectively. The identification of these fungi revealed Fomes fomentarius (L.) Fr. and Ganoderma lucidum (Curtis) P. Karst. as highly abundant on hornbeam and oak, respectively. Highest fungal abundance was observed at an altitude range of 1150-1200 meters above sea level. Diversity of macro-fungi was determined and the mean Shannon diversity index was found to be 2.52 and 1.94 for hornbeam and oak, respectively, and mean equitability was calculated as 0.84 and 0.73 for hornbeam and oak, respectively. There were no significant differences in the Shannon Diversity Index or equitability. Overall, current work showed that most of the identified fungi were classified as white rot fungi.  相似文献   
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