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21.
Squamous cell carcinoma of the nail bed is a relatively uncommon tumour that may be diagnosed only after considerable delay. The first case presented is a 79-year-old man with a history of discomfort and discoloration affecting the right thumbnail of 3 years duration. The second case is a 70-year-old man who presented with a recurrent, offensive discharge from beneath the left thumbnail of 40 years duration. Clinical examination of the affected digits revealed minor nail abnormalities. The presence of tumour was fully apparent only after removal of the nail plate and inspection and biopsy of the nail bed. The cases demonstrate that subungual squamous cell carcinoma may present with prolonged symptoms and a deceptively benign appearance. The importance of consideration of the possibility of malignancy, removal of the nail plate for inspection of the nail bed and appropriate biopsy is emphasized.  相似文献   
22.
Dainiak  N; Riordan  MA; Strauss  PR; Feldman  L; Kreczko  S 《Blood》1988,72(1):165-171
We have investigated the role of contractile proteins of circulating mononuclear cells in generation of membrane-associated, erythroid growth regulatory molecules. Lymphocytes and monocytes were incubated under serum-free conditions without and with cytochalasin B, cytochalasin D, or colchicine, and effects on positive and negative erythropoietic activities were determined in cell membranes and in surface membrane vesicle-rich pellets and supernatants of dialyzed medium conditioned by the cells. In serum-free cultures of human bone marrow, plasma membranes and exfoliated membrane-derived vesicles from cytochalasin-treated lymphocytes lost their capacity to support the formation of erythroid bursts, while monocyte membrane-associated inhibitory activity was abolished by preincubation with cytochalasin. In contrast, membrane-associated activities of colchicine-treated cells were unaffected. Cytochalasin-induced alterations of membrane regulatory molecules were observed in a dose-dependent fashion over a wide range of concentrations (1 to 100 micrograms/mL) tested. However, the capacity of membrane vesicle-free supernatants of medium conditioned by lymphocytes or monocytes was unaffected by cytochalasins, regardless of drug concentration used. Lysates of cytochalasin B-treated cells inhibited the activity of deoxyribonuclease I to a greater degree than did lysates of untreated cells, suggesting that the relative amount of monomeric actin is increased in the cytoplasm of treated cells. Furthermore, results of experiments with D-glucose and with cytochalasin D suggest that cytochalasin effects are independent of alterations in glucose metabolism. The data indicate that expression of plasma membrane- associated regulators is sensitive to agents that block polymerization of actin. They raise the possibility that changes in distribution of actin between unpolymerized and filamentous pools may influence the organization and/or function of mononuclear cell surface-associated erythroid regulatory molecules.  相似文献   
23.
This study analyses the influence of female and male patient age and human menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and live birth rates with ovulation stimulation using HMG in combination with intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI treatment cycles in 184 patients carried out at a university fertility centre were analysed in a retrospective fashion. The main outcomes measured were clinical pregnancy rates and live birth rates. Increased female partner age (> or = 35) and male partner age (> or = 40) were found to negatively influence pregnancy rates with HMG/ IUI therapy. In addition, this study demonstrated a critical threshold of HMG requirements beyond which pregnancy did not occur. No pregnancies occurred in treatment cycles requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular maturity, irrespective of patient age. In conclusion, female partner age, male partner age, and HMG requirements all significantly influence pregnancy rates with HMG/IUI therapy.   相似文献   
24.
We examined if rat myometrial cells in culture generate nitric oxide (NO) and express various isoforms of NO synthase (NOS). Myometrial cells isolated from rats on day 18 of gestation were incubated with various stimulators and inhibitors of NOS for 24 and 48 h, and NO production was evaluated by measuring nitrites in the media and NOS proteins in the cell lysates. NO was produced by myometrial cells and its production inhibited by N(G)-methyl-L-arginine (L-NMMA). This inhibition was reversed by L-arginine (3 mM). Interleukin-1beta (IL- 1beta) significantly stimulated NO production, in a dose-dependent manner. The IL-1beta-stimulated NO production was inhibited by the NOS inhibitor, L-NMMA, whose effects were reversed by L-arginine. Abundant NOS III protein was detectable in freshly isolated myometrial cells, and this was maintained in culture in the presence of fetal bovine serum (FBS; 10%). In the absence of FBS, NOS III levels decreased significantly (by 90%) within 24 h. In contrast, NOS I and NOS II proteins were undetectable in freshly isolated muscle cells and in cells cultured without IL-1beta. However, NOS II protein in these cells was induced by IL-1beta. Thus, NO is produced by myometrial cells through the NOS III isoform, and the myometrial NO may be important in maintaining uterine quiescence during pregnancy.   相似文献   
25.
To validate the level of olfactory performance of children, we tested 825 volunteers, aged 4–17 years, with an abbreviated form of our pediatric odorant identification task. The test consisted of sniffing and identifying five odorants (baby powder, bubble gum, candy cane, licorice and peach). Mean olfactory scores increased as a function of age, reaching a plateau of about 94–95% correct at 8 years of age. In general, girls out–performed boys. Physicians require a test instrument such as the one we have devised to allow them to diagnose olfactory dysfunction in children. The present task is particularly applicable in screening large numbers of children in clinics or schools because it can be administered easily and rapidly. Adult subjects with olfactory dysfunction also performed poorly on this odorant identification task designed for children. Therefore, we expect that our odorant identification task will also detect children with severe olfactory dysfunction.  相似文献   
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27.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
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