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71.
The cytoskeleton in keratinocytes is a complex of highly homologous structural proteins derived from two families of type I and type II polypeptides. Keratin K2e is a type II polypeptide that is expressed in epidermis late in differentiation. Here we report the influence of keratinocyte activation, proliferation, and keratinization on K2e expression in samples of cutaneous and oral lesions. The normal expression of K2e in the upper spinous and granular layers of interfollicular epidermis is increased in keloid scars but showed distinct down-regulation in psoriasis and hypertrophic scars where keratinocytes are known to undergo activation. Unlike normal and psoriatic skin, K2e expression in hypertrophic and keloid scars began in the deepest suprabasal layer. In cutaneous basal and squamous cell carcinomas, K2e was absent in most tumor islands but the overlying epidermis showed strong expression. No significant K2e expression in nonkeratinized or keratinized oral epithelia, including buccal mucosa, lateral border of tongue and gingiva was detected. In oral lichen planus K2e expression was undetectable, but in benign keratoses of lingual mucosa induction of K2e along with K1 and K10 was observed. In mild-to-moderate oral dysplasia with orthokeratinization, K2e was highly expressed compared with parakeratinized areas but in severe dysplasia as well as in oral squamous cell carcinoma, K2e expression was undetectable. Taken together, the data suggest that K2e expression in skin is sensitive to keratinocyte activation but its up-regulation in oral lesions is a reflection of the degree of orthokeratinization.  相似文献   
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Thirty-five percent of all ischemic events remain classified as cryptogenic. This study was conducted to ascertain the accuracy of diagnosis of ischaemic stroke based on information given in the medical notes. It was tested by applying the clinical information to the (TOAST) criteria. Hundred and five patients presented with acute stroke between Jan-Jun 2007. Data was collected on 90 patients. Male to female ratio was 39:51 with age range of 47-93 years. Sixty (67%) patients had total/partial anterior circulation stroke; 5 (5.6%) had a lacunar stroke and in 25 (28%) the mechanism of stroke could not be identified. Four (4.4%) patients with small vessel disease were anticoagulated; 5 (5.6%) with atrial fibrillation received antiplatelet therapy and 2 (2.2%) patients with atrial fibrillation underwent CEA. This study revealed deficiencies in the clinical assessment of patients and treatment was not tailored to the mechanism of stroke in some patients.  相似文献   
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Background  

The present study was conducted to evaluate the in vitro and in vivo antioxidant properties of aqueous extract of Podophyllum hexandrum. The antioxidant potential of the plant extract under in vitro situations was evaluated by using two separate methods, inhibition of superoxide radical and hydrogen peroxide radical. Carbon tetrachloride (CCl4) is a well known toxicant and exposure to this chemical is known to induce oxidative stress and causes tissue damage by the formation of free radicals.  相似文献   
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Introduction

Trauma is a major contributor to global morbidity and mortality, and injury to the central nervous system is the most common cause of death in these patients. While the provision of surgical services is being recognized as essential to global public health efforts, specialty areas such as neurosurgery remain overlooked.

Method

This is a retrospective case review of patients with operable lesions, such as extra-axial hematomas and unstable depressed skull fractures that underwent neurosurgical interventions under local anesthesia.

Results

A total of 13 patients underwent neurosurgical intervention under local anesthesia. Two and three patients with burr hole decompression of epidural and subdural hematomas, respectively; seven patients had elevation of depressed skull fractures and lastly one patient had an aspiration of a brain abscess. All patients survived with and without residual neurological deficits.

Conclusion

Access to resources and staff required to deliver general anesthesia is challenging in resource-poor settings. We have therefore begun performing emergent interventions under local anesthesia, with or without conscious sedation. While some patients had some minor residual weakness after the procedure, the degree of neurological deficit was improved from that observed before the procedure in all patients.
  相似文献   
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OBJECTIVES: The aim of this study is to investigate erectile response to intraurethral administration of papaverine in rats. MATERIAL AND METHODS: Male Sprague-Dawley rats were used in this study. Under urethane anesthesia, penis was exposed and intracavernous pressure (ICP) was recorded through a 23-gauge needle, which was inserted into right corpus cavernosum. Effects of intraurethral application of incremental doses of 0.2 ml papaverine gel (4-17.5 mg) on intracavernosal pressure were observed and compared with those of 0.4 mg papaverine applied into corpus cavernosum. Mean arterial blood pressure (MABP) and heart rate were also monitored. RESULTS: The mean basal ICP was 8.9 +/- 1.8 mm Hg. Intraurethral administration of papaverine did not increase ICP at any doses used in this study. After intracavernous injection of papaverine (0.4 mg), a significant increase in the ICP occurred from resting (8.9 +/- 1.8 mm Hg) to a peak at 57.5 +/- 9.9 mm Hg and persisted for 22.3 +/- 6.7 minutes (p < 0.05). The latter application significantly decreased MABP (22.3 +/- 3.1 mm Hg; p < 0.05). CONCLUSIONS: Intraurethral administration of papaverine does not seem to be an alternative to other erectile dysfunction treatment modalities. However, further studies on animals are necessary at higher concentrations or in combination with other mucosal enhancers to increase the effect of intraurethral administration of papaverine.  相似文献   
80.
Background: Modifications of implant design have been intending to improve primary stability. However, little is known about investigation of a hybrid self‐tapping implant on primary stability. Purposes: The aims of this study were to evaluate the primary stability of two hybrid self‐tapping implants compared to one cylindrical non‐self‐tapping implant, and to elucidate the relevance of drilling protocols on primary stability in an ex vivo model. Materials and Methods: Two types of hybrid self‐tapping implants (Straumann® Bone Level implant [BL], Straumann® Tapered Effect implant [TE]) and one type of cylindrical non‐self‐tapping implant (Straumann® Standard Plus implant [SP]) were investigated in the study. In porcine iliac cancellous bones, 10 implants each were inserted either using standard drilling or under‐dimensioned drilling protocol. The evaluation of implant‐bone interface stability was carried out by records of maximum insertion torque, the Periotest® (Siemens, Bensheim, Germany), the resonance frequency analysis (RFA), and the push‐out test. Results: In each drilling group, the maximum insertion torque values of BL and TE were significantly higher than SP (p = .014 and p = .047, respectively). In each group, the Periotest values of TE were significantly lower than SP (p = .036 and p = .033, respectively). The Periotest values of BL and TE were significantly lower in the group of under‐dimensioned drilling than standard drilling (p = .002 and p = .02, respectively). In the RFA, no statistical significances were found in implants between two groups and between implants in each group. In each group, the push‐out values of BL and TE were significantly higher than SP (p = .006 and p = .049, respectively). Conclusion: Hybrid self‐tapping implants could achieve a high primary stability which predicts them for use in low‐density bone. However, there is still a debate to clarify the influence of under‐dimensioned drilling on primary stability.  相似文献   
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