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21.
We examined 1,054 melanocytic nevi [137 (13%) simple lentigines, 158 (15%) junctional nevi, 337 (32%) compound nevi, and 422 (40%) dermal nevi] for the presence of lymphohistiocytic infiltrates. The following criteria were evaluated: age and sex of the patient, location, histological type, horizontal and vertical diameter, increase of melanocytes in the basal layer of the epidermis, increase of melanophages in the papillary dermis, melanin content of keratinocytes, and melanin content of nevus cells. Lymphohistiocytic infiltrates were measured semiquantitatively; their presence within the center, in the lateral margins, or both was also determined. The results were analyzed statistically by means of chi-square tests and univariate and multivariate analyses. We found that 824 lesions (78%) were associated with a lymphohistiocytic infiltrate; whereas 230 (22%) were not. This infiltrate was weak in 273 cases (33%), moderate in 411 cases (50%), pronounced in 130 cases (16%), and very strong in 10 cases (1%). Multivariate analyses revealed that the only criteria associated with the presence of lymphohistiocytic infiltrates were the increase of melanocytes in the basal layer and the vertical thickness in compound nevi. All other parameters were statistically insignificant. We conclude that melanocytic nevi with a junctional hyperplasia of melanocytes--i.e., mostly early stages such as simple lentigines, junctional nevi, and superficial compound nevi--are often associated with a moderate to pronounced cellular stromal reaction. Their presence may reflect the appearance of antigens on proliferating melanocytes. It may also represent a stromal reaction to necrotic tumor cells and keratinocytes within the dermoepidermal junction. These findings rule out any relationship to an increase of melanin pigment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Since November 1997, 14 successive cases of occupational contact dermatitis were observed in 13 laboratory technicians and 1 physician, working in a genetics laboratory in Leuven (Belgium) in 3 laboratories of bacteriology in Strasbourg, Montbeliard and Angers, and in the laboratory of hematology in Bordeaux (France). The dermatitis, located on the hands, forearms and face, relapsed after each exposure to an immersion oil for microscopy. Patch tests performed in 10 patients were positive to epoxy resin (ER) in the European standard series (10/10 patients) and to newly formulated Leica immersion oil (7/7), 1 patient testing negatively with the former oil. A breakdown performed in 2 patients with the oil's ingredients confirmed sensitization to liquid modified ER components, contained at >80% concentration in the oil. The presence of DGEBA was demonstrated by HPLC analysis at a +/-30% rate. Although the safety data sheet indicated a revision of the formula, nobody was alerted to the risk of sensitization and the need for skin protection. ERs, as a source of occupational allergy, can provoke epidemics of contact dermatitis in industry. This report of epidemic contact dermatitis from ERs, used for their optical properties in an immersion oil for microscopy, emphasizes the need for perpetual vigilance in occupational medicine and the usefulness of multicentre contacts in dermato-allergology.  相似文献   
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A preterm neonate at 29‐week gestational age was born with intrauterine growth restriction, severe pancytopaenia and gross skeletal dysplasia. Antenatal screening bloods, TORCH/parvovirus tests and karyotype were unremarkable. Postnatally, he had normal microarray comparative genomic hybridization and serum B12/folate levels, and human immunodeficiency virus and cytomegalovirus polymerase chain reaction and antoimmune screening were negative. Targeted gene testing for Shwachman–Diamond syndrome (SDS) revealed the pathognomic mutation (c.183_184delTAinsCT). His postnatal clinical course was complicated by: (i) Ventilator dependency because of a combination of a pathologically compliant chest wall and preterm‐associated chronic lung disease. (ii) Progressive bone marrow failure, resulting in transfusion dependence and profound neutropenia associated with recurrent sepsis. (iii) Gastrointestinal failure and TPN dependency. (iv) Poor postnatal growth with weight/length/head circumference all <3rd centile. (v) Prognostication was complicated by the lack of published literature on the presentation of SDS in a preterm infant. However, because of inexorable progression of multiorgan failure, intensive care was withdrawn on day 54 of life. SDS is a rare autosomal recessive disorder characterised by haematological abnormalities, skeletal dysplasia and exocrine pancreatic dysfunction. Neonatal presentation is thought to be extremely rare. However, with the availability of genetic testing, it has now become clear that because of overlap in clinical presentation, term‐born infants with skeletal dysplasia and severe respiratory distress may initially be misdiagnosed as asphyxiating thoracic dystrophy. This case report highlights the complexities of preterm birth complicating clinical manifestations of SDS.  相似文献   
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Background

The middle colic artery (MCA) is of crucial importance in abdominal surgery, for laparoscopic or open right and transverse colectomies. Against this background, a high number of reports concerning anatomical variations of the MCA have been published intended to contribute to the improvement of operative techniques for the treatment of colon cancer. Despite this extensive literature, briefly reviewed in the present paper, a course of the MCA posterior to the superior mesenteric vein, called a retromesenteric trajectory, has been related to only once, to the best of our knowledge.

Methods

A total series of 507 patients included in two prospective trials concerning laparoscopic or open right colectomy for cancer between 2011 and 2017 are reported. The investigation included preoperative or postoperative multidetector-computed tomography angiography.

Results

We found four (0.79%) cases of retromesenteric MCA. They all underwent meticulous image analysis with mesenteric vessels’ road mapping, detailed morphometry, and surgical validation which revealed that, apart from their course, those cases did not differ significantly from the rest of the series.

Conclusion

This paper therefore documents the worth-knowing behavior causing considerable confusion for the operating surgeon unaware of the abnormality and shows its concrete impact on patient-tailored surgical practice, in particular for laparoscopic D3 colectomy (including the “uncinated process first” approach).
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INTRODUCTION

The Triathlon® (Stryker, Kalamazoo, MI, US) total knee replacement was designed to improve patient function and survivorship. The aim of this study was to determine whether the Triathlon® prosthesis produces better patient reported outcomes than a previous design by the same manufacturer, the Kinemax Plus.

METHODS

The outcome of 233 knees of patients with a mean age of 68 years (range: 40–80 years) who received the Kinemax Plus prosthesis were compared with the outcomes of 220 knees of patients with a mean age of 70 years (range: 42–90 years) who received the Triathlon® prosthesis. Data were collected via postal questionnaire prior to surgery as well as at 8–12 weeks and at 1 year following surgery. Validated questionnaires were used including the WOMAC® (Western Ontario and McMaster Universities) pain and function scales, the Knee injury and Osteoarthritis Outcome Score quality of life scale and the self-administered patient satisfaction scale.

RESULTS

This study found that patients who had the Triathlon® prosthesis had significantly better pain relief (p<0.0001), function (p=0.028), knee related quality of life (p<0.0001) and satisfaction (p=0.0003) at three months after surgery than those who received the Kinemax Plus prosthesis. In addition, knee related quality of life (p=0.002) and satisfaction (p=0.021) were significantly higher at one year after surgery in Triathlon® patients.

CONCLUSIONS

The findings suggest that return to function and reduction in pain may occur more quickly in patients with a Triathlon® prosthesis than in those with the Kinemax Plus.  相似文献   
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