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31.
Background: Q-switched lasers are conventionally used for the treatment of black tattoo. However, they require multiple sittings, and the response may be slow due to competing epidermal pigment in dark skin. Objective: To compare the efficacy of Q-switched Nd:YAG laser alone with its combination with ultrapulse CO2 for the removal of black tattoo. Materials and methods: Sixty patients with black tattoo were randomized into two groups viz., group A and group B. Group A was treated with QS Nd:YAG laser (1064 nm) alone, and group B received combination of ablative ultrapulse CO2 followed by fixed-dose QS Nd:YAG laser (1064 nm), at 6-week interval for a maximum of 6 sittings. After each sitting, 3 independent physicians noted percentage of improvement that was evaluated using visual analogue scale (VAS) and grading system for tattoo ink lightening (TIL). Results: Combination laser (group B) showed statistically significant improvement in mean VAS score in the last 2 noted visits as compared to 1st session (p < 0.007, p < 0.001) and TIL mean score in last three noted visits as compared to 1st session (p < 0.008, p < 0.020, and p < 0.004). There was no statistically significant difference in the side effect profile of both the groups. Conclusion: For refractory professional tattoos, combination of ultrapulse CO2 laser and QS Nd:YAG laser is superior to QS Nd:YAG laser alone.  相似文献   
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This case details the development of a rapidly growing polypoid mass in the proximal stomach in a patient with known attenuated familial adenomatous polyposis. Surgical resection was required and histology showed hyperplasia with extensive areas of dysplastic adenomatous change. This case illustrates that patients with the attenuated form of familial adenomatous polyposis are at risk for multiple neoplasia distinct from those patients with the classic form of familial adenomatous polyposis.  相似文献   
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This study compared the pain sensitivity in healthy women at the abdomen and lower back (presumed referral areas of menstrual pain), thigh and arm (control areas), in the menstrual, ovulatory, luteal and premenstrual phases of confirmed ovulatory cycles, with that of males. The pressure pain threshold (PPT) and pinch pain threshold (PiPT) was determined by an electronic pressure algometer, heat pain threshold (HPT) by a contact thermode and tactile threshold (TT) with von Frey hairs. The abdominal PPT was significantly lower in females in all menstrual phases as compared to the control sites ( p<0.0007). The abdominal and lower back HPT was significantly lower in females in all menstrual phases compared with control areas, and to the sites in males ( p<0.002). The TT was significantly reduced in females compared with males ( p< 0.013). There was no difference in the PiPT between females and males. In males, the HPT, PPT and TT were not different within any site. During the ovulatory phase, the HPT was significantly reduced at the abdomen and the PPT at the back compared with the menstrual, luteal and premenstrual phases (p<0.0002). There were no within-menstrual phase variations in the PiPT and TT at any site, or for the HPT and PPT at the control areas. The reduced thresholds in menstruating women may be due to the presence of latent uterine algogenic stimuli, and the increased levels of oestrogen and leuteinizing hormone at ovulation may enhance nociception by acting both at the peripheral and central level, resulting in the hypersensitivity changes at the abdomen and lower back areas.  相似文献   
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We examined the effect of substrate stiffness on the beating rate, force of contraction, and cytoskeletal structure of embryonic chicken cardiac myocytes by culturing them on laminin-coated polyacrylamide (PA) substrates. Cells cultured on PA substrates with elasticity comparable to that of the native myocardium (18 kPa) exhibited the highest beating rate during the first few days of culture. The initial beating rate of individual cells on all the substrates varied significantly but began to converge within 5 days. We also examined the focal adhesions (FAs) and cytoskeletal structure on different substrates via confocal microscopy and found a higher percentage of FAs on tissue culture (TC) plastic dishes compared with the softer PA gels. Furthermore, highly aligned sarcomeric striations were clearly visible on 18 kPa, 50 kPa, and TC dish, whereas cells on 1 kPa only showed nonaligned diffused striations. The force of contraction on these substrates was measured using a micro-electromechanical system force sensor, which showed that the force of contraction for the cells on TC dishes (F = 71.30 ± 6.38 nN) was significantly larger than those cultured on the 18-kPa PA gel (F = 30.16 ± 3.83 nN). This is most likely due to the formation of higher percentage of FAs on the TC dishes compared with fewer FAs on the softer gels. Our cumulative findings can have a significant impact on the design of 3D cardiac tissue engineered scaffolds.  相似文献   
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Ameloblastoma is the most common epithelial odontogenic tumor, comprising 1% of tumors and cysts arising in the jaws. We describe two cases of ameloblastoma of the jaw diagnosed by fine-needle aspiration cytology. The patients presented with swelling in the parotid region. Cytological examination of the particulate and sticky bloodstained fluid obtained on aspiration showed tightly packed groups of basaloid cells arranged in nests with rounded edges. Palisading epithelial cells and squamous cells with spherical keratinized bodies were the distinctive cytological features. Histologic examination confirmed the presence of ameloblastoma.  相似文献   
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Process apt microbial proteases due to their wide range industrial applications have become the focus of intense scientific research during recent years. Considering the hostile process milieu, the proteases intended for application must be robust enough to withstand the extremes of temperature and pH, and presence of organic solvents and other potential enzyme inhibitors. Current study presents the characterization of a robust protease from a previously isolated bacterium Bacillus subtilis K‐1 (BSK‐1). Purification of BSK‐1 protease (5.21‐fold) was achieved to homogeneity by salt (ammonium sulfate) precipitation, and ion‐exchange (diethyl‐aminoethyl‐sephadex) and size exclusion chromatography (Sephadex G‐100). Molecular weight of BSK‐1 protease was determined by SDS‐PAGE analysis (42 kDa). Though the optimum temperature and pH for BSK‐1 protease activity was 50 °C and 10, respectively, but, the protease exhibited remarkable activity and stability over elevated temperatures (60–80 °C) and a broad pH range (pH 7–11). Protease showed resistance towards several organic solvents/other potential enzyme inhibitors. Drastic activity loss in presence of phenylmethylsulfonyl fluoride indicated that the enzyme is a serine protease. Kinetic parameters (Km and Vmax) for BSK‐1 protease were found to be 0.14 mg ml?1 and 1176 mg min?1, respectively. Putative amino acid sequence of BSK‐1 protease (derived from nucleotide sequence of protease gene) suggested that the enzyme belonged to peptidases S8/S53 super family with multidomain of S8. BSK‐1 protease being stable under harsh conditions may serve a model system for understanding the molecular basis of stability, and may help designing novel proteases that are suitable for industrial applications.  相似文献   
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