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21.
The histologic distinction between peritoneal epithelioid mesotheliomas and serous carcinomas diffusely involving the peritoneum may be difficult, but it can be facilitated by the use of immunohistochemistry and electron microscopy. D2-40 and podoplanin are two recently recognized lymphatic endothelial markers that can be expressed in normal mesothelial cells and mesotheliomas. The purpose of this study is to compare the value of these new mesothelial markers with those that are commonly used for discriminating between mesotheliomas and serous carcinomas, and also to determine the current role of electron microscopy in distinguishing between these malignancies. A total of 40 peritoneal epithelioid mesotheliomas and 45 serous carcinomas of the ovary (15 primary, 30 metastatic to the peritoneum) were investigated for the expression of the following markers: D2-40, podoplanin, calretinin, keratin 5/6, thrombomodulin, MOC-31, Ber-EP4, B72.3 (TAG-72), BG-8 (Lewis(Y)), CA19-9, and leu-M1 (CD15). All 40 (100%) of the mesotheliomas reacted for calretinin, 93% for D2-40, 93% for podoplanin, 93% for keratin 5/6, 73% for thrombomodulin, 13% for Ber-EP4, 5% for MOC-31, 3% for BG-8, and none for B72.3, CA19-9, or leu-M1. All 45 (100%) serous carcinomas were positive for Ber-EP4, 98% for MOC-31, 73% for B72.3, 73% for BG-8, 67% for CA19-9, 58% for leu-M1, 31% for keratin 5/6, 31% for calretinin, 13% for D2-40, 13% for podoplanin, and 4% for thrombomodulin. After analyzing the results, it is concluded that Ber-EP4 and MOC-31 are the best negative mesothelioma markers for differentiating between epithelioid mesotheliomas and serous carcinomas. The best discriminators among the positive markers for mesotheliomas are D2-40, podoplanin, and calretinin. From a practical point of view, Ber-EP4 and MOC-31, in combination with calretinin, and/or D2-40 or podoplanin allow the differential diagnosis to be established between mesothelioma and serous carcinoma in nearly all instances. As a clear distinction could be made between these two malignancies in all of the cases in which electron microscopy was performed, this technique can be very useful in establishing the correct diagnosis when the immunohistochemical results are equivocal or further support of a diagnosis of either mesothelioma or serous carcinoma is needed.  相似文献   
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Medullary thyroid carcinoma (MTC) is a rare form of thyroid cancer representing about 10% of all thyroid malignancies. It occurs mostly as a sporadic tumor or in association with autosomal dominant inherited cancer syndromes--multiple endocrine neoplasia (MEN) types 2A and 2B and familial MTC. Germline mutations in exons 8, 10, 11, 13, 14, 15 and 16 of the RET proto-oncogene are found in most of the familial cases. There are only a few published data reporting multiple germline mutations in the RET proto-oncogene. We have detected double germline mutations in 2 different exons on the same RET allele in two MEN 2 families. In the MEN 2A family, double germline mutation in exons 10 (Cys620Phe) and 13 (Tyr791Phe) was detected. In the MEN 2B family, beside the classical germline mutation in exon 16 (Met918Thr) a second germline mutation in exon 13 (Tyr791Phe) was found. This study revealed that MEN 2 syndromes can also be caused by double germline mutations in the RET proto-oncogene and these families can be added to small worldwide cohort of families with multiple germline mutations.  相似文献   
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The aim of the study was to evaluate differences in the relationship between peripheral diabetic neuropathy and microvascular reactivity in type 1 and type 2 diabetic patients. Twenty-eight type 1 and 37 type 2 diabetic patients were included in the study. Control groups consisted of 18 and 25, age and body mass index matched healthy persons. The presence of peripheral neuropathy was estimated by vibration perception threshold higher than 20 V evaluated by biothesiometry. Microvascular reactivity was examined by laser doppler fluxmetry using postocclusive reactive hyperemia and thermal hyperemia. The following variables of vascular reactivity were examined: peak flow after occlusion as a difference between maximal and basal perfusion (PORH (max)), mean velocity increase during postocclusive hyperemia (PORH (max)/t (1)), peak flow during thermal hyperemia (TH (max)) and the mean velocity increase in the perfusion during thermal hyperemia (TH (max)/t (2)). These parameters are expressed in perfusion units (PU) or in perfusion units per second (PU . s (-1)). The microvascular reactivity in type 1 diabetic patients without evidence of peripheral neuropathy was comparable with that in healthy persons and it was significantly higher than in type 1 diabetic patients with peripheral neuropathy in all tested parameters (PORH (max): 64 [40; 81] PU vs. 24 [17; 40] PU, p < 0.001, PORH (max)/t (1): 5.41 [2.69; 8.18] PU/s vs. 1.21 [0.69; 2.5] PU/s, p < 0.001, TH (max): 105 [77; 156] PU vs. 56 [46; 85] PU, p < 0.001 and TH (max)/t (2): 2.48 [1.67; 3.33] PU/s vs. 0.87 [0.73; 1.06] PU/s, p < 0.001). On the contrary, no difference in the microvascular reactivity parameters was found between type 2 diabetic patients with and without neuropathy (PORH (max): 48 [30; 60] PU vs. 49 [36; 57] PU, NS, PORH (max)/t (1): 3.46 [2.15; 5.19] PU/s vs. 3.29 [2.45; 4.8] PU/s, NS, TH (max): 95 [78; 156] PU vs. 97 [73; 127] PU, NS and TH (max)/t (2): 1.45 [0.95; 2.84] PU/s vs. 1.37 [1.12; 1.95] PU/s, NS). In both these groups microvascular reactivity was comparable with that estimated in the age and BMI matched healthy persons. An inverse relationship was observed between microvascular reactivity and vibratory perception threshold in type 1 diabetic patients, but it was not true in type 2 diabetic patients. We suppose that the pathogenesis of neuropathy and impaired microvascular reactivity may be differently influenced by metabolic factors in type 1 and type 2 diabetic patients.  相似文献   
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There is some evidence suggesting that Parkinson's disease (PD) patients exhibit lower body weight when compared to age-matched healthy subjects. Low body mass index (BMI) is correlated with low bone mineral density, both of which are major risk factors for hip fractures. Possible determinants of weight loss in PD patients include hyposmia, impaired hand-mouth coordination, difficulty chewing, dysphagia, intestinal hypomotility, depression, decreased reward processing of dopaminergic mesolimbic regions, nausea, and anorexia as the side effects of medication, and increased energy requirements due to muscular rigidity and involuntary movements. It is unclear whether PD patients in general, or only a subgroup of those affected, definitely show lower BMI in the advanced stages of the disease. We therefore recommend that the body weight of PD patients be monitored monthly as the disease progresses, and that a patient's nutrition should be supplemented with sufficient amounts of vitamin D and calcium to reduce the risk of hip fractures and strengthen bone density. Because meal times may coincide with unpredictable off periods associated with akinesia and impaired hand-mouth coordination, PD patients also need flexible food schedules that accommodate the associated symptoms of this disease.  相似文献   
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We report the case of a 38-year-old woman who presented with chronic lower abdominal pain. Her past medical history included a splenectomy due to abdominal trauma. Ultrasound examination revealed four pelvic tumors which, upon laparotomy, were found to be the result of splenosis. Approximately 100 cases of splenosis have been reported but only a minority of them have been published in the gynecological literature. Our case indicates that those involved in pelvic scanning (even of asymptomatic women) and/or treating those complaining of lower abdominal pain or presenting with pelvic tumors should be aware of splenosis as a possible diagnosis.  相似文献   
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