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Melanoma is the most common malignant tumor in which melanin synthesis occurs, although other nonmelanocytic tumors synthesize melanin or contain nonneoplastic melanocytes. We present two cases of infiltrating pigmented squamous cell carcinoma of the skin and review the clinical, morphologic, and ultrastructural features. Melanin was found in epithelial tumor cells as well as in macrophages and dendritic melanocytes. Interestingly, one of the neoplasms was associated with an adjacent melanocytic nevus and pigmented solar keratosis. Immunohistochemical analysis showed that neoplastic cells stained for keratin and melanin-filled dendritic cells were found to be S-100 protein and HMB45 positive. A careless examination of the immunohistochemical stains for S-100 protein and HMB45 could cause the misdiagnosis of melanoma, a neoplasm that has a more ominous outlook. 相似文献
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J Varani ME Zeigler P Perone TE Carey SC Datta 《Canadian Metallurgical Quarterly》1997,111(1-2):51-57
A chronic, loose constriction of the sciatic nerve in rat produces behavioral signs of spontaneous pain and cutaneous hyperalgesia (Bennett and Xie, Pain, 33 (1988) 87-107) as well as an abnormal spontaneous activity and adrenergic sensitivity of certain dorsal root ganglion (DRG) cells with axons in the injured nerve (Kajander et al., Neurosci. Lett., 138 (1992) 225-228; Xie et al., J. Neurophysiol., 73 (1995)1811-1820). The present study investigated whether the spontaneous activity and adrenergic sensitivity were intrinsic properties of injured DRG cells and manifested in vitro, i.e., not dependent on intact blood circulation and an intact, functioning sympathetic nervous system. Two weeks after a loose constriction of the sciatic nerve, the L4 or L5 DRG with its ligated nerve and dorsal root attached was removed from the rat and placed in a chamber. Extracellular recordings were made from teased dorsal root fibers. Spontaneous activity (>0.05 imp/s in 3 min) originating within or close to the DRG was often found in C-, Adelta- and Abeta-fibers from nerve-injured rats, but was rare in fibers with peripheral axons from uninjured nerve. The incidence of various patterns of spontaneous discharge was similar to that previously recorded in vivo. Nineteen of 30 C-fibers, four of five Adelta- and three of seven Abeta-fibers from injured nerve responded to different doses of norepinephrine (NE) applied topically to the DRG. Five of seven C- and one of two Abeta -fibers from injured nerve responded to clonidine, a more selective alpha2 adrenergic agonist. The thresholds ranged from 500 to 10 microM, the lowest dose delivered. None of the fibers from uninjured nerve responded to NE or clonidine (500 microM). Since the experiments were carried out in vitro in the intact DRG, the existence of spontaneous activity in DRG cells in nerve-injured rats was independent of any blood borne chemicals, such as norepinephrine. We hypothesize that abnormal activity and adrenergic sensitivity in injured DRG neurons are due to an intrinsic alteration of the cell body membrane. 相似文献
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PURPOSE: Valproate (VPA) has been linked to coagulation disturbances, with both impaired and exaggerated clotting, which has been attributed to an effect of VPA on platelets or hemostatic proteins. Additional thrombocytic function testing may help to identify patients at risk of increased bleeding caused by platelet dysfunction. METHODS: We evaluated the influence of VPA on hematologic routine values and platelet activation by using immunostaining and flow cytometry in 30 patients receiving long-term VPA therapy and in 30 controls. RESULTS: The fraction of activated platelets was similar in both groups; however, the general extent of platelet activation was significantly lower in the patient group, with considerable interindividual variability. In addition, patients had a significantly lower platelet count, prolonged thrombin time, and higher mean corpuscular hemoglobin. CONCLUSIONS: Our data confirm the previously reported hematologic changes caused by VPA and additionally suggest that VPA impairs procoagulatory thrombocytic function, which is reflected by reduced platelet activation and increased thrombin time. Possible mechanisms of VPA-platelet interaction are discussed. 相似文献
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SM Lele ES Gloster ER Heilman PC Chen CK Chen AP Anzil JN Pozner MJ Reardon 《Canadian Metallurgical Quarterly》1997,24(3):193-196
In adult mammals fever is associated with the reduction of blood plasma iron level. Immature mammals, however, show either a decrease (precocial animals such as guinea pig neonates) or a lack of reduction (altricial animals such as human neonates) of plasma iron in response to endotoxin. In order to determine whether this difference is connected with maturity just after delivery, plasma iron concentration, hematocrit, body temperature and body mass were measured in rat pups injected with E. coli endotoxin in doses of 50 or 200 micrograms kg-1. Rat pups, like human neonates, are altricial animals. In 7-day-old rats injection of LPS led to a dose-dependent decrease in plasma iron level. The fall in plasma iron was accompanied by changes in body temperature and body mass. The results showed that plasma iron response to endotoxin in altricial rat neonates is similar to that observed in precocial guinea pig pups. 相似文献
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C Monteagudo E Jordá C Carda C Illueca A Peydró A Llombart-Bosch 《Canadian Metallurgical Quarterly》1997,31(4):367-373
BACKGROUND: Radial keratotomy may induce late hyperopic shift. We present data on 140 consecutive eyes with a follow-up of up to 3 years that underwent radial keratotomy with the RK suction bridge. METHODS: We conducted a retrospective study of 140 consecutive eyes that had radial keratotomy between 1987 and 1994. Mean preoperative spherical equivalent was -5.21 D (range -2.00 to -9.75 D). All operations were performed by one surgeon (JHK) with the RK suction bridge. A suction ring maintaining physiological intraocular pressure immobilized the eye and left a peripheral rim of uncut cornea. The ring incorporated an eccentric bridge that guided the radial keratotomy knife. The knife setting was 90% of the central corneal thickness, measured by pachymetry. Spherical equivalent refraction and spectacle corrected visual acuity were measured at 1 week, 1, 3, 6 months, 1 year, and 3 years after radial keratotomy. RESULTS: The mean preoperative spherical equivalent refraction of -5.21 D dropped to -0.43 D at 1 week (n = 136), -0.71D at 1 month (n = 120), -0.85 D at 3 months (n = 95), -0.74 D at 6 months (n = 73), -0.77 D at 12 months (n = 79), and -0.85 D at 3 years (n = 67). Compared to 1 month spherical equivalent, at 3 years three eyes (4.4%) had moved > = or 1.00 D toward hyperopia. One eye (1.4%) shifted by 1.25 D. Paired t-tests of mean spherical equivalent refraction did not reveal significant shifts toward hyperopia. Mean preoperative spectacle-corrected visual acuity was slightly diminished at 1 week and was equal or better thereafter. CONCLUSIONS: Our 3-year data suggest that a late hyperopic shift following radial keratotomy may be prevented if an intact peripheral rim is maintained and cutting depth does not exceed 90% of the lowest corneal thickness. 相似文献
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Verrucous carcinoma is a variant of squamous cell carcinoma and should be distinguished from benign papilloma and well-differentiated nonverrucous squamous cell carcinoma. It is rare tumor of the sinonasal tract. Occasionally, conventional squamous cell carcinomatous components may be seen in verrucous carcinoma. This entity is called a hybrid verrucous squamous cell carcinoma. We report a case of hybrid verrucous squamous cell carcinoma occurring in the nasal cavity and paranasal sinus of a 67-year-old male. The removed mass shows the typical feature of verrucous carcinoma, but focally conventional squamous cell carcinomatous area is also noted. The treatment of this case follows verrucous carcinoma, but close follow up is mandatory because it may potentially spread to regional lymph nodes in contrast to pure form of verrucous carcinoma. 相似文献
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Primary carcinoma of the lung is unusual in children and the squamous cell variant is extremely rare. This, to the best of our knowledge, is the sixth reported case of bronchogenic squamous cell carcinoma in childhood. 相似文献
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Squamous cell carcinoma is the second most common skin cancer in humans and has a rate of metastasis of 0.5%-5.9%. Regional lymphadenectomy is generally not recommended for patients with advanced lesions and clinically node-negative disease. Selective lymphadenectomy using preoperative lymphoscintigraphy and intraoperative radiolymphoscintigraphy and vital dye injections to identify the sentinel lymph node may help in staging patients with upper-extremity squamous cell carcinoma while avoiding the complications of a complete axillary node dissection. The case of a patient with a large squamous cell carcinoma of the wrist with clinically negative findings on axillary examination who was found to have a sentinel lymph node containing metastatic tumor is presented. Although this treatment method is still considered investigational, it holds great promise for nodal staging by being able to detect occult metastatic nodal disease in otherwise clinically node-negative patients. 相似文献
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M Frisch C Fenger AJ van den Brule P S?rensen CJ Meijer JM Walboomers HO Adami M Melbye B Glimelius 《Canadian Metallurgical Quarterly》1999,59(3):753-757
Investigators participating in the Epidemiologic Study of Cystic Fibrosis project began to collect microbiological, pulmonary, and nutritional data on cystic fibrosis (CF) patients at 180 North American sites in 1994. Part of this study was a survey undertaken in August 1995 to determine microbiology laboratory practices with regard to pulmonary specimens from CF patients. The survey included a section on test ordering, completed by a site clinician, and a section on test performance and reporting, completed by each site's clinical microbiology laboratory staff. Seventy-nine percent of the surveys were returned. There was intersite consistency of microbiology laboratory practices in most cases. The majority of sites follow most of the CF Foundation consensus conference recommendations. There were differences in the frequency at which specimens for culture were obtained, in the use of selective media for Staphylococcus aureus and Haemophilus influenzae, and in the use of a prolonged incubation for Burkholderia cepacia. These variations in practice contribute to prevalence differences among sites and may result in differences in clinical care. 相似文献
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Squamous cell carcinoma is the most common form of oral cancer, and causes more deaths than any other oral disease. Dentists and dental auxiliaries must know the clinical, etiologic, pathogenetic and prognostic features of squamous cell carcinoma to ensure appropriate screening and diagnosis of the patient. It is now recognized that cancers are genetic diseases, which arise from inherited genetic factors and exposure to exogenous carcinogens that alter the DNA of cells. Increasingly, the genetic events that contribute to the development of cancers at many sites within the body are being identified, and the complex series of genetic steps required for fully-developed neoplasia to arise in the oral cavity are being better characterized. This article reviews recent advances in the understanding of the etiology and pathogenesis of oral carcinoma, including the involvement of various oncogenes, tumor suppressor genes and viruses. 相似文献
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K Yamazaki T Ishida K Ondo K Yamamoto T Odashiro G Saito A Kido Y Sasaki H Yukaya K Sugio K Sugimachi 《Canadian Metallurgical Quarterly》1998,28(10):1081-1083
Sclerosing sweat-duct carcinoma is a rare malignancy of the skin. We herein present the case of a 68-year-old Japanese man who developed sclerosing sweat-duct carcinoma 2 years after undergoing local excision of a primary tumor in his right arm. Firm nodules appeared in the right axilla, which were revealed by surgical resection to be metastases. This rare tumor grows slowly but usually metastasizes to the regional lymph nodes, whereupon they are often associated with a poor prognosis. As the effectiveness of chemotherapy and radiotherapy against this neoplasm remains unclear, we recommend that the disease should initially be aggressively treated by surgery, which would also be indicated for any metastatic lesions. 相似文献
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T Hirai Y Korogi S Hamatake I Ikushima Y Shigematsu M Takahashi Y Ando T Arima M Ando 《Canadian Metallurgical Quarterly》1996,69(828):1187-1190
The authors describe a 32-year-old male in whom herpes zoster of the left upper extremity was complicated by the development of cervical myelitis. Contrast enhancement and abnormal signal intensity on T1 and T2 weighted images was seen at C1-C6 levels in the spinal cord and medulla. There was also slight enlargement of the cord at these levels. On serial MR imaging the degree of enhancement changed from marked to none with corresponding clinical improvement. 相似文献