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21.
A retrospective study was performed between 1985 and 1994 on paediatric patients operated for asymptomatic intrascrotal or testicular palpable masses. Tumour was suspected in each case and it was surgically explored. Twenty-six children were affected, their age ranging between 9 days and 14 years. In 11 cases testicular torsion, in 4 epididymitis and in another 2 dystrophic calcification were found. Tumours, including rather rare alterations, were observed in only 9 children. The present results draw attention to the tumour-like occurrence of testicular torsions and other benign alterations of the scrotum.  相似文献   
22.
Zusammenfassung Bei einem 21 jähr. Studenten, der zur Zeit einer Grippeepidemie eine Influenza durchgemacht hatte, traten 2 Wochen darauf zuerst kompletter Block mit Ohnmachtsanfällen, später nach Wiederherstellung der normalen Schlagfolge Störungen der Reizbildung und insbesondere der Reizausbreitung sowohl im Vorhof als auch in besonders ausgedehntem Maße innerhalb der Kammer auf, die auf eine diffuse Erkrankung des spezifischen Muskelsystems hinwiesen. Gleichzeitig bestanden Oppressionsgefühl auf der Brust, Mattigkeit, vorübergehend geringe Temperatursteigerungen. Alle diese Symptome werden als Grippe-Myokarditis gedeutet. Besonders wertvoll für die Erkennung dieses und ähnlicher Krankheitsbilder erweist sich die elektrokardiographische Untersuchung, die auch beim Fehlen anderer auf die Myokardaffektion bezüglichen Symptome, insbesondere auch von Arhythmien, durch den Nachweis von Störungen der Erregungsausbreitung in Vorhof oder Kammer Aufklärung über das Bestehen eines pathologischen Prozesses im Myokard zu geben vermag. Die frühzeitige Erkennung dieses Krankheitszustandes ist aber mit Rücksicht auf die notwendigen prophylaktischen Maßnahmen von großer Wichtigkeit.  相似文献   
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β-hemolytic streptococcal infection in developing countries still causes thousands of cases of Rheumatic Fever (RF). Molecular mimicry between streptococcal M protein (strep M) and heart components has been proposed as the triggering factor leading to autoimmunity in individuals with genetic susceptibility, which is linked to different HLA-DR alleles in different populations. In our hands, RF was significantly associated to HLA-DR7/53. Previous work in our lab has shown that heart-infiltrating T cells that simultaneously recognize strep M and heart proteins. Further, such T cells predominantly recognized the 81-103 strep M5 epitope. In this work, we analysed the proliferative response of peripheral blood mononuclear cells of 99 RF patients and 40 normal controls. Eighty-nine of the RF patients were HLA-typed. As among heart-infiltrating T cells, the 81-103 strep M5 protein epitope is the most frequently recognized epitope among RF PBMC (35.4%), against a 7.5% frequency of proliferation among normal controls (p=0.0018, chi square). However, the 81-103 epitope was as frequently recognized by HLA-DR7,53 positive as by negative individuals (45.2% vs 54.8%, respectively). Taken together, the results suggest that the 81-103 strep M5 epitope may be the immunodominant epitope, “promiscuously” recognized by T cells in a genetically diverse population. The demonstration that molecular mimicry is targeted to a discrete immunodominant “promiscuous” epitope in strep M5 may allow the development of a safe anti-streptococcal synthetic vaccine devoid of such epitopes.  相似文献   
25.
The triggering of the respiratory burst by phagocytosis via different receptors in monocytes of patients with systemic lupus erythematosus (SLE) was investigated. The superoxide anion synthesis was assayed by reduction of ferricytochrome C that was inhibited by superoxide dismutase. The mononuclear cell suspensions were triggered by IgG-coated latex, C3 complement fragment-coated and uncoated yeast (Saccharomyces cerevisiae). Superoxide generation induced by phagocytosis via Fc gamma R was decreased in monocytes of patients with SLE. On the other hand, MoAbs against Fc gamma RI, Fc gamma RII and especially CR3 could also induce superoxide anion synthesis. At the same time, superoxide generation induced by anti-CR3 could be inhibited with C3-coated yeast.  相似文献   
26.
Several of the major variable factors in the Syrian hamster embryo/simian adenovirus SA7 (SHE/SA7) viral enhancement assay were identified and the effects of these parameters on assay sensitivity were assessed. The extent of dose-dependent cytotoxicity and enhancement of SA7 transformation of primary SHE target cells by benzo(a)pyrene was examined through analysis of data obtained from 37 assays performed over a 2-year period. The variables analyzed for contribution to assay sensitivity included the number of SA7-induced transformed SHE cell foci enumerated in ten replicate dishes in the negative control condition (background focus count) (range: 26-139); the age of the SHE cell cultures at the time of exposure to benzo(a)pyrene (range: 72-144 hr postseeding); and the source of the pregnant hamsters used to prepare the primary SHE cells (Wilmington colony vs Lakeview colony, Charles River Laboratories, Inc., Wilmington, MA). The benzo(a)pyrene-induced cytotoxicity and enhancement of SA7 transformation responses were found to be independent of each of these variables, within the range of values tested.  相似文献   
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The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors.  相似文献   
29.
We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia.  相似文献   
30.
A silver staining technique for nucleolar organizer regions (NORs) has been applied to bone marrow biopsies of various types of acute and chronic leukaemias. This method could be easily evaluated on resin-embedded bone marrow obtained from acute lymphocytic leukaemia (n = 12), acute myelogenous (n = 16), chronic lymphocytic (n = 16) and chronic granulocytic (n = 20) leukaemia. A significant difference (p < or = 0.1) was only found between the AgNOR numbers in nuclei of lymphocytes from acute and chronic leukaemia (mean of 1.23 to 1.40 and 1.58) and those of cells from acute and chronic myelogenous leukaemia (from a mean of 5.00 to 9.17 per nucleus). However, no significant difference was observed among cells of various types of acute and chronic myelogenous leukaemias, despite of their markedly higher staining intensity and proliferative activity. The greatest mean of AgNOR numbers was counted in monoblasts of acute myelomonocytic leukaemia. It is suggested, that higher AgNOR counts in nuclei of more malignant leukaemic cells are in parallel with their mitotic activity and could be related to their elevated cell turn-over.  相似文献   
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