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31.
Neuropathological findings in two siblings with familial erythrophagocytic lymphohistiocytosis (FEL) are reported. Case 1 showed the typical neuropathological findings of FEL with lymphohistiocytic infiltration of the leptomeninges and perivascular spaces. A characteristic erythrophagocytosis was detected in inguinal lymph nodes, lung and bone marrow. Case 2 revealed calcification and necrotic lesions in the brain. In the necrotic areas, parenchymal calcification, vascular medial calcification, and occlusion of many vessels due to subendothelial fibrosis were detected. The areas of necrosis correlated with the distribution of occluded vessels. These changes were most prominent in putamen, internal capsule, thalamus and dentate nucleus. Hypercytokinemia is suspected to be the underlying mechanism for the clinical and laboratory findings in patients with FEL, although the relationship to the vascular pathology is unclear.  相似文献   
32.
The most common cause of death in patients with colorectal cancer is metastatic liver disease. In order to identify patients at a high risk of developing hepatic secondaries from colorectal cancers, DNA content was measured in metastasizing colorectal primaries (Group I, n= 32) as well as in their subsequently resected liver secondaries and in sections of non-metastasizing colorectal cancers (Group II, n= 25). A modified interpretation system involving both a DNA index and percentage of cycling cells (those in S and G2 + M phases) was developed. DNA content was measured in paraffin-embedded sections by flow cytometry using internal controls (human peripheral blood mononuclear cells) and non-malignant tissue controls (19 patients with diverticular disease). In Group I there were significantly more tumours with both abnormal ploidy (aneuploid or abnormal tetraploid peak) and > 15% cycling cells compared with Group II (Chi-squared; P= 0.034). The combination of abnormal ploidy and > 15% cycling cells was superior to Dukes’ classification for identifying metastasizing tumours (Logistic Regression; P= 0.047). However, it was not possible to discriminate between the two groups using either DNA ploidy or the percentage of cycling cells alone. The metastasizing colorectal cancers exhibited similar DNA ploidy characteristics and had a similar percentage of cycling cells compared with their liver metastases. These results suggest that tumour DNA ploidy plus the percentage of cycling cells may predict the development of liver metastases and thus survival in patients with colorectal cancer.  相似文献   
33.
The features of enamel hypoplasia in a small group of patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) are described. Using a recently developed method, the authors evaluated quantitatively the amount of defect in each tooth by measuring the width of the hypoplastic lesions and dividing the value by the crown height. They then assessed the degree of damage in each tooth type (from central incisors to second premolars) and patient. Canines were the most severely affected among maxillary and mandibular teeth, but all tooth types were involved. Analysing both the differences between patients and their age at the beginning of the defect, the authors observe that hypoparathyroidism is not responsible for the onset of enamel hypoplasia in APECED, although it may contribute to the damage.  相似文献   
34.
Orthotopic liver transplantation (OLT) is now a definitive treatment option for most cases of endstage liver disease (ESLD) in children. Efforts now focus on active supportive treatment to maintain, if not improve, the patient's clinical status before OLT and to ensure normal patterns of growth and development after OLT. Malnutrition adversely affects the outcome of OLT and is probably the single area in pre-operative management where the largest potential improvement can be made. Our studies indicate significant abnormalities of protein energy metabolism and body composition in children referred for OLT. We have shown that the use of enteral formulae, enriched with branched-chain amino acids, have significant advantages. Other adjunctive therapy, such as growth hormone, is the subject of current investigation. Following transplantation, catch-up weight and growth does occur with the advent of normal liver functioning, but patients at continuing risk for undernutrition, such as those with rejection and/or chronic infection, need to be targeted for specific nutritional therapy.  相似文献   
35.
The pharmacokinetics of a single oral dose of the neuroleptic drug zuclopenthixol (10 or 6 mg) was studied in 6 extensive and 6 poor metabolizers of debrisoquine. The peak plasma concentrations of zuclopenthixol did not differ between the phenotypes, whereas the plasma elimination half-life was significantly longer in poor than in extensive metabolizers (29.9 +/- 6.6 vs 17.6 +/- 6.9 h). Accordingly, the total oral plasma clearance was lower in poor than in extensive metabolizers (0.78 +/- 0.27 vs 2.12 +/- 0.65 1/h/kg). Ten of the volunteers had previously participated in a similar study in which the kinetics of perphenazine, another neuroleptic drug, were studied in poor and in extensive metabolizers of debrisoquine. There was a significant correlation between the oral clearance of perphenazine and that of zuclopenthixol among these 10 subjects. The study indicates that the disposition of zuclopenthixol, as well as that of perphenazine, is related to the genetically determined capacity to hydroxylate debrisoquine. The significance of this polymorphism for the clinical use of neuroleptics is discussed.  相似文献   
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Summary A comparative study was undertaken to investigate the application of a specially adapted microsurgical Neodymium Yag Laser system with a wavelength of 1,319 m and a CO2 laser system for laser assisted microvascular end-to-end anastomosis (LAMA) of the rat femoral artery. Conventionally sutured anastomoses served as controls. Postoperative investigations included patency tests, light microscopy and tensile strength measurements. Both laser systems seem to be equally suitable for LAMA: The patency rates do not differ from those of sutured anstomoses and formation of microscopically small aneurysms occurred predominantly in control animals and only once in laser groups. The clamp time needed for LAMA was half the time that was needed for sutured anastomoses. Wound healing in all groups was similar with less fibrotic reactions and less foreign body granulomas in laser groups. At all intervals tensile strength was significantly higher for sutured anastomoses while differences between the CO2- and the ND: Yag-laser groups were not statistically significant. Potential applications in urology include microvascular anastomoses in erectile dysfunction, pediatric and reconstructive urology.Contains parts of a dissertation  相似文献   
40.
Summary Changes in capillary walls between human glial, non-glial and metastatic brain tumors were studied with conventional ultrathin section and freeze-fracture replica techniques. The following results were obtained. (1) In glial tumors, ultrathin section studies showed cell junctions of the capillaries were either short or elongate. Moreover, endothelial hyperplasia, surface infolding of endothelial cells, irregularity of the basal lamina and a large extravascular space were observed. Freeze-fracture replicas of capillary endothelium showed tight junctions as two to seven strands. In addition, pinocytotic vesicles had increased markedly and were an average of 25 per m2. Both ultrathin and freeze fracture studies showed that, in contrast to malignant gliomas, there were only slight changes in benign astrocytomas. (2) In non-glial tumors, ultrathin sections showed surface infoldings, increased vesicles, many fenestrations of endothelial cells, irregularity of basal lamina and enlarged perivascular space. Freeze-fracture replicas of vascular endothelium, showed that the average number of pinocytotic vesicles and fenestrations were 25 and 22 per m2, respectively. Moreover, the tight junction was composed of one or two strands which appeared to be a discontinuous array of particles. (3) In metastatic brain tumors, ultrathin studies showed capillary endothelia were proliferated, had marked infolding, and showed an increased number of pinocytotic vesicles and many fenestrations. Moreover, short and elongate intercellular junctions were presented but no open junction was detected. Finally the basal lamina lost its three-layered appearance and was irregular in width. Freeze-fracture replicas showed pinocytotic vesicles had increased and were 24 per m2 on average in four cases, but fenestrations and tight junctions could not be detected. The most fundamental feature of vessels in these three different kinds of tumors was whether they were fenestrated or not. Glial tumors were non-fenestrated, whereas non-glial and metastatic tumors were fenestrated.  相似文献   
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