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101.
Observations differ on the pre-invasive malignant lesions associated with the various categories of testicular germ cell tumours. Such lesions have been found to be similar in appearance and are assumed to be composed of multipotent cells, or conversely a distinctive pre-invasive stage has been reported in association with each form of germ cell neoplasm. This study was undertaken to see whether distinctive morphological and immunohistochemical features of carcinoma in situ adjacent to various categories of germ cell tumours could be established. Carcinoma in situ adjacent to seminomas, teratomas and mixed germ cell tumours in 18 adults was indistinguishable morphologically. Placental alkaline phosphatase was demonstrated immunohistochemically but vimentin and low molecular weight cytokeratins were uniformly absent in these abnormal germ cells from all three groups. These findings support the concept of a multipotent pre-invasive malignant cell for both seminoma and teratoma in the adult. Carcinoma in situ was not seen adjacent to 15 spermatocytic seminomas, nor was placental alkaline phosphatase demonstrated in tubules adjacent to these tumours. These negative findings are additional evidence that spermatocytic seminoma differs from classical seminoma in its histogenesis. Carcinoma in situ, as defined morphologically and immunohistochemically in adults, was not identified adjacent to yolk sac tumours and differentiated teratomas in 20 prepubertal testes. The possibility that pre-invasive malignancy in children may not resemble that in adults must be considered when assessing the malignant potential of cryptorchid testes on biopsies taken during orchidopexy. 相似文献
102.
Sofia Avnet Annavera Lamolinara Nicoletta Zini Liliana Solimando Gianni Quacquaruccio Donatella Granchi Nadir Mario Maraldi Armando Giunti Nicola Baldini 《Journal of orthopaedic research》2006,24(8):1699-1708
Cathepsin K is a cystein protease that displays a proteolytic activity against Type I collagen and is abundantly and selectively expressed in osteoclasts where it plays a critical role in bone degradation. Its direct role in bone tissue has been defined by knock-out mice studies and inhibiting strategies in animals models. However, direct proof of cathepsin K function in human osteoclast model in vitro is lacking. The aim of this study is to analyze cathepsin K expression and localization in human osteoclasts obtained from peripheral blood and to examine cathepsin K function in these cells by antisense oligodeoxynucleotide (AS-ODN) strategy. AS-ODN was added to the culture of osteoclast precursors induced to differentiate by RANKL and M-CSF. AS-ODN treatment produced a significant down-regulation of cathepsin K mRNA (>80%) and protein expression, as verified respectively by Real-time PCR and by immunocytochemistry or Western blot. The cathepsin K inhibition caused an impairment of resorption activity as evaluated by a pit formation assay ( p = 0.045) and by electron microscopy, while the acidification process was unaffected. We demonstrated that antisense strategies against cathepsin K are selectively effective to inhibit resorption activity in human osteoclasts, like in animal models. 相似文献
103.
When excluding haemophilia and von Willebrand disease, coagulation factors deficiencies constitute rare autosomal recessive disorders (<1 in 500,000) of less precisely defined epidemiology. We have reported herein the distribution of these entities in the French Basque Country, a genetic isolate of very old individualization with peculiar biological specificities. The prevalence of these disorders was markedly high, especially, as already shown, factor XI deficiency. This unusual profile needs to be discussed in the view of population genetics. 相似文献
104.
Knut A. Selvig Ulf M. E. Wikesjö Gary C. Bogle Richard D. Finkelman 《Journal of clinical periodontology》1994,21(6):380-385
Abstract. Effects of a topically applied growth factor combination on fibroblast migration, collagen fiber formation and bone regeneration were studied in standardized periodontal defects in 4 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and into the dentin of maxillary and mandibular teeth. Collagen sponges, impregnated with 200 ng insulin-like growth factor II, 20 ng basic fibroblast growth factor and 6 ng transforming growth factor beta 1 were fitted to defects randomly in right or left quadrants and the flaps repositioned and sutured. Contralateral control defects received the collagen with vehicle only. Experimental procedures were staggered to allow observations of healing 3, 7, 10, and 14 days after surgery. Histometric analysis showed no differences in fibroblast and collagen density between control and growth factor defects. Bone regeneration was significantly greater in control than in growth factor defects 10 and 14 days after surgery. The rate of healing generally appeared more affected by intra-dog variations or procedural variations than by the growth factor combination. 相似文献
105.
T. A. Zolotareva G. A. Gorchakova V. L. Konovalenko L. N. Konovalenko A. Yu. Grishanova L. F. Gulyaeva V. V. Lyakhovich 《Bulletin of experimental biology and medicine》1992,113(5):671-673
Laboratory of Experimental Therapy, Institute of Balneology, Ministry of Health of the Ukraine, Odessa. Department of Cell Physiology and Pathology, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences V. Ya. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 5, pp. 498–500, May, 1992. 相似文献
106.
Levels of cardiovascular risk factors were determined in 75 patients with Type 2 diabetes mellitus. The patients were divided into three groups according to their urinary protein excretion (UPE): (a) normal proteinuria (less than or equal to 70 mg d-1); (b) microproteinuria (70-500 mg d-1); and (c) macroproteinuria (greater than 500 mg d-1). A significant stepwise increase in mean systolic blood pressure, LDL-cholesterol and fibrinogen levels was observed from the first to the third investigated group of patients. Mean apoprotein B levels were significantly increased in the group with macroproteinuria compared to the other two groups. Significant linear correlations were found between UPE and LDL-cholesterol, total cholesterol, apoprotein B, creatinine, systolic blood pressure and diabetes duration. In summary, it is concluded that the levels of some cardiovascular risk factors increase with the stage of proteinuria in Type 2 diabetes mellitus. 相似文献
107.
108.
Douglas A. Drossman 《Stress and health》1994,10(1):49-55
The irritable bowel syndrome (IBS) is a very common disorder of intestinal function characterized by variable symptoms of abdominal pain, diarrhea, constipation and bloating. The spectrum of severity ranges from mild symptoms, not worthy of clinical attention, to intense and continuous symptoms associated with impaired health-related quality of life and high health care use. Psychosocial disturbance is commonly found among patients with irritable bowel, but until recently, its precise role in the disorder was uncertain. The data now suggest that irritable bowel is not a psychiatric disorder per se, but psychosocial factors including life stress, psychiatric comorbidity and abnormal illness behavior, among others, influence how the illness is experienced and acted upon. Patients with mild symptoms usually respond to education, reassurance, dietary modification and, when needed, antimotility agents. However, patients with more severe symptoms, who usually have greater psychosocial disturbance, will also require behavioral interventions, and possibly psychopharmacological agents. In sum, a graduated, multicomponent plan of care that includes dietary, behavioral and pharmacological treatments is recommended. 相似文献
109.
To study the phenotypic specificity of S-100 beta and insulin-like growth factor II (IGF-II) for developing monoamine neurons, serotonin (5-HT) neurons from the embryonic day 14 (E14) rostral raphe or dopamine (TH) neurons from the substantia nigra/ventral tegmental area were cultured for 3 days in vitro (3 DIV) in the presence of these factors. Neuronotrophic effects were analyzed by computer-assisted morphometry of 5-HT and TH-immunoreactive neurons. S-100 beta and IGF-II differentially regulated the growth of 5-HT and TH neurons but did not affect their survival. S-100 beta significantly increased several parameters of neurite outgrowth by 5-HT neurons but inhibited the spatial extent (field area) of TH neurites. IGF-II promoted growth of cell bodies of both phenotype, but only stimulated neurite outgrowth by TH neurons. S-100 beta and IGF-II differentially affected the number of GFAP immunoreactive cells from raphe and substantia nigra, but these effects did not correlate with the specificity of neuronotrophic effects. S-100 beta and IGF-II immunoreactivities were expressed in glial cultures derived from the same brain regions, raising the possibility that these factors have autocrine effects on glia as well as paracrine actions on neurons. The results of this study suggest that specificity of neurotrophic factors for particular embryonic neurons may be correlated with their neurotransmitter phenotype. 相似文献
110.
目的 探讨膀胱前间隙炎性假瘤的临床病理特征及发病因素,以提高对本病的认识。方法 复习3例膀胱前间隙炎性假瘤的临床特征、组织病理学、免疫表型及相关文献。结果 3例患者均为女性,均为输卵管结扎术后1~2年发现膀胱前间隙炎性假瘤,CT及B超提示膀胱前壁肿块,但膀胱黏膜光滑。术中发现肿块位于膀胱前间隙并累及膀胱前壁。病理检查:眼观为灰白色质韧的结节状肿块,镜下见炎性假瘤的病理特征及不同程度炎症背景,有组织疏松区、黏液样区、部分区域梭形细胞和纤维母细胞排列杂乱,细胞较大,光镜检查时易误诊为肉瘤,但缺乏核异型。3例均成功行肿块连同部分膀胱壁切除术,随访3~5年无复发。结论 膀胱前间隙炎性假瘤形态上需与软组织肉瘤、结节性筋膜炎、术后梭形细胞结节、间质性膀胱炎等疾病相鉴别,既往输卵管结扎术和感染可能是其重要的致病因素。 相似文献