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91.
92.
Topical photodynamic therapy (PDT) with methyl-aminolevulinate (MAL) is a well-established treatment for precancerous skin lesions and non-melanoma skin cancer. Treatment outcomes are less effective for thick than for superficial lesions, which are presumed to be due to insufficient PpIX biodistribution in tumour tissue. Hexyl-aminolevulinate (HAL) is a more lipophilic photosensitizer precursor than MAL and may penetrate the skin to a greater depth and more homogeneously. We compared HAL- and MAL-induced PpIX accumulation in specific skin compartments using concentrations of 2%, 6% and 20% HAL and MAL on long-term UV-irradiated mouse skin. Furthermore, 20% HAL and 20% MAL were applied to non-irradiated skin. Porphyrin fluorescence was measured by fluorescence microscopy in selected skin regions: the epidermis, superficial dermis, deep dermis and sebaceous gland epithelium down to a depth of 1 mm. We found higher PpIX fluorescence intensities in epidermis and sebaceous gland epithelium from 2%, 6% and 20% HAL (median 72-104 au) than in corresponding concentrations of MAL (median 35-69 au) (P < 0.01). Fluorescence intensities in the superficial (35 au) and deep dermis (32 au) were similar for HAL and MAL (P = 0.51) and lower than epidermal fluorescence intensities (P < 0.001). Significantly, higher median PpIX fluorescence intensities (64 au) were found in 20% MAL-incubated skin irradiated with UV than in non-irradiated skin (48 au) (P < 0.001). HAL-induced fluorescence intensities did not depend on UV exposure (HAL 20%, UV: 72 au, non-UV: 70 au) (P = 0.87). In conclusion, HAL express high affinity for epidermis and sebaceous gland epithelium, and MAL for actinically damaged skin, which raises future perspectives for improved selectivity in PDT.  相似文献   
93.
94.
AIM: The aim of this study was to assess the impact of long-term physical training on left ventricular longitudinal contraction by strain rate analysis and tissue tracking imaging. METHODS AND RESULTS: The study population comprised 17 male elite endurance and 15 male elite strength athletes and 12 male control subjects of similar age. Tissue Doppler imaging was recorded in the apical views and used for analysis of the longitudinal systolic myocardial velocity, annular diastolic velocities, strain rate and tissue tracking. Left ventricular mass index was significantly increased in both endurance athletes (209+/-40 g/m(2)) and strength athletes (138+/-38 g/m(2)) compared with normal subjects (96+/-20 g/m(2), P<0.001). Tissue tracking score index and mean strain rate of the 16 segments were significantly increased in strength athletes (7.9+/-1.1 mm and -1.4+/-0.3 s(-1), respectively) compared with endurance athletes (7.5+/-0.9 mm and -1.0+/-0.4 s(-1), P<0.01 for both) and normal subjects (7.4+/-1.0 mm and -1.0+/-0.3 s(-1), P<0.01 for both). CONCLUSION: Despite significant left ventricular hypertrophy and extensive training in elite athletes, we found normal longitudinal left ventricular systolic function, and in strength athletes performing isometric exercise even increased function.  相似文献   
95.
96.
Small (less than 1 mm), superficial erosions ('microerosions') have been observed stereo-microscopically in surface-stained rectal biopsies in Crohn's disease (CD). Biopsy specimens from 97 patients with CD, 225 with ulcerative colitis (UC), and a control material of 161 patients were investigated to define the occurrence and significance of the microerosions. In CD they were found in 13% of specimens, in UC in 5%, and in the control material not at all. In CD they were observed only in patients with colonic involvement and were most frequent (44%) in patients with this site of affection exclusively. Granulomas were identified in 62% of the biopsies with microerosions and by examination of two consecutive biopsies from each of these patients, in 85% indicating a positive correlation. In patients with microerosions and a primary diagnosis of UC, granulomas were found in 38% and by examination of two biopsies in 54%. Patients with granulomas and a few other patients were reclassified as CD, but there still remained some patients with microerosions, who most probably had UC. In conclusion, microerosions are observed mainly in CD with colonic involvement. There is a high incidence of granulomas in biopsy specimens with microerosions. The demonstration of microerosions in a specimen is suggestive of, but probably not diagnostic of, CD.  相似文献   
97.
P Kirkegaard  P S Olsen  E Nex?  J J Holst  S S Poulsen 《Gut》1984,25(11):1225-1229
The effect of VIP and somatostatin on secretion of epidermal growth factor and bicarbonate from Brunner's glands was investigated in the rat. Vasoactive intestinal polypeptide infused in doses of 10 and 100 ng/kg/h significantly increased epidermal growth factor and bicarbonate output, but the concentrations did not change. Somatostatin infused at doses of 1, 10, 100 and 1000 ng/kg/h against a background of VIP 100 ng/kg/h inhibited in dose-dependent fashion the stimulated epidermal growth factor and bicarbonate outputs from rat Brunner's gland pouches. Also basal secretion was inhibited by somatostatin. Infusion of antisomatostatin serum stimulated Brunner's gland secretion. By immunohistochemical studies of rat duodena, it was found that epidermal growth factor, is almost exclusively present in the secretory cells of Brunner's glands. It is concluded that VIP stimulates secretion of epidermal growth factor and bicarbonate from Brunner's glands, an effect which is inhibited by somatostatin. A possible role for somatostatin in the control of Brunner's gland secretion is suggested.  相似文献   
98.
International Journal of Paediatric Dentistry 2011 Aim. To assess the relation between type of traumatic injury and use of pacifier at the time of a fall accident in 0‐ to 2‐year olds. Material and methods. The study draws on data from the database on traumatic dental injuries at the Department of Oral and Maxillofacial Surgery, Copenhagen University Hospital. Results. The study includes 1125 patients ≤2 years of age, representing a total of 1886 injuries. A total of 176 patients had fallen while using a pacifier, whereas 949 children suffered a fall without using a pacifier. In the pacifier group, 11.9% had crown fractures compared with 20.0% of children who had fallen without a pacifier (P = 0.012). Tooth displacement (lateral luxation, extrusion or avulsion) was relatively more frequent in children falling with a pacifier compared to children falling without a pacifier (64.8%vs 54.8%; P = 0.014). Furthermore, soft tissue injury was less frequent among the former (28.4%vs 38.3%; P = 0.013). Conclusions. Injuries occurring while using a pacifier tend to be tooth displacement rather than fractures. This is in accordance with the theoretical consideration that a blunt impact tends to favour displacement, whereas a sharp impact tends to favour fractures of the hard dental tissues.  相似文献   
99.

Introduction

The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care.

Methods

A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications.

Results

A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar.

Conclusions

Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.  相似文献   
100.
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