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91.
AM Manganoni† C Farisoglio† G Tucci† F Facchetti‡ PG Calzavara Pinton† 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1333-1336
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases. 相似文献
92.
Alveolar hydatid disease. Review of the surgical experience in 42 cases of active disease among Alaskan Eskimos. 总被引:7,自引:0,他引:7
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OBJECTIVE: The authors reviewed the pathophysiology and clinical management of endemic alveolar hydatid disease in Alaskan Eskimos, incorporating recent developments in diagnosis and treatment. SUMMARY BACKGROUND DATA: Alveolar hydatid disease is a highly lethal zoonotic infection caused by the larval stage of Echinococcus multilocularis. This cestode is restricted geographically to northern climates, where foxes and small rodents represent the natural hosts. Domestic dogs also may serve as definitive hosts, and thus, transmit the parasite to humans. Human infection is characterized by the development of a cancer-like hepatic mass, which may extend to adjacent structures or metastasize to distant sites. If the infection goes untreated, mortality reaches 80%. METHODS: The medical records of all patients with alveolar hydatid disease diagnosed or treated at the Alaska Native Medical Center between 1951 and 1993 were reviewed. Forty-two cases of active disease are presented. RESULTS: Nine patients underwent resection of hepatic lesions with intent to cure, and each had a favorable result. Average post-diagnosis survival of those patients was 22 years; six still are living and free of disease. Partial resections or drainage procedures were performed in ten patients. Chemotherapy was used to augment the surgical treatment of eight patients, and four received chemotherapy alone, resulting in improved outcomes compared with historic controls. Late complications included hepatic abscess, biliary obstruction, and portal venous hypertension. CONCLUSIONS: Whereas alveolar hydatid disease rarely is encountered in other areas of North America, the biologic potential for spread of the disease may be increasing because of illegal importation of infected foxes to the Eastern seaboard. Therefore, the surgical community should maintain an awareness of the diagnosis and management of this potentially devastating parasitic infection. 相似文献
93.
MASATO FUKUDA MD AKINOBU HATA MD SHIN-ICHI NIWA MD KEN-ICHI HIRAMATSU MD MASAFUMI YOKOKOJI MD SEIKI HAYASHIDA AM KENJI ITOH DENG KAZUYUKI NAKAGOME MD AKIRA IWANAMI MD 《Psychiatry and clinical neurosciences》1996,50(2):85-88
Abstract A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature. 相似文献
94.
The cytotoxicity of the anti-leukaemia drug amsacrine (m-AMSA) has been suggested to result from its oxidative metabolism to the corresponding quinonediimine, N1'-methanesulphonyl-N4'-(9-acridinyl)-3'-methoxy-2',5'-cyclohexad iene-1',4'- diimine (mAQDI). The metabolic fate of mAQDI was examined in cultured CHO cells (subline AA8) to identify the end products to be expected following oxidative metabolism of m-AMSA. [Acridinyl-G-3H]-m-AQDI was rapidly accumulated by AA8 cells in phosphate buffered saline with complete conversion in less than one minute to m-AMSA, macromolecular adducts and polar low molecular weight species, each of these three classes being formed in approximately equal amounts. Two of the polar products were chromatographically identical to those formed on reaction of m-AQDI with reduced glutathione. These were identified by 1H NMR spectroscopy as the 1,4-addition product 5'-(S-glutathionyl)-m-AMSA and the previously unreported isomeric 6'-(S-glutathionyl)-m-AMSA. These thiol adducts were also formed rapidly from m-AQDI in deproteinized cell lysates indicating a non-enzymatic process, although the possibility of enzymatic catalysis in intact cells has not been eliminated. The absence of such products in AA8 cells after treatment with m-AMSA places an upper limit of 1% per hour on the rate of its oxidative metabolism in these cells and suggests that generation of m-AQDI is unlikely to be responsible for the cytotoxicity of m-AMSA in cultured tumour cells. 相似文献
95.
Magnetic resonance imaging of nonmetallic orbital foreign bodies 总被引:2,自引:0,他引:2
W B Wilson J N Dreisbach D E Lattin J C Stears 《American journal of ophthalmology》1988,105(6):612-617
We studied a cadaver head model in which we inserted three orbital foreign bodies. We chose these foreign bodies because of their similarity to substances found in orbital trauma. Teflon and Lucite were used to represent synthetic materials, and dry pine was chosen as a type of organic material. Lucite is similar in radiographic density to plastics used in interior trim for automobiles and spectacle frames. While both orbital ultrasound and plain skull films failed to detect the foreign bodies consistently, both computed tomography and magnetic resonance imaging detected and localized the foreign bodies relatively well. Computed tomography was better in delineating shape and characterizing composition. 相似文献
96.
97.
98.
Using a simplified procedure, we have extracted DNA from unstained paraffin sections of needle biopsies of kidney and liver transplants and identified the presence of CMV using the polymerase chain reaction. This method utilizes oligonucleotide primers for two genes shown to be specific for cytomegalovirus (CMV) as well as an internal control gene (hemoglobin) in a single reaction. Utilizing nested PCR amplification with agarose gel electrophoresis, CMV can be detected without radioisotopes to a level of sensitivity equivalent to one one-hundredth of a cytomegalic virocyte per cm2 of a 3-microM paraffin section. This method is applicable to situations where only scarce paraffin-embedded tissue is available. 相似文献
99.
This study was designed to evaluate the routine use of a gum elastic bougie for tracheal intubation. The median time to intubation with the gum elastic bougie while simulating an 'epiglottis only' view was only 10 s longer than the time taken during conventional intubation with an optimum view. Three of the patients required a gum elastic bougie-assisted intubation after attempts at conventional visual intubation had failed. There was no significant difference in the incidence of postoperative sore throat and hoarseness between the two groups. We recommend that anaesthetists should use the gum elastic bougie whenever a good view of the glottis is not immediately obtained. 相似文献
100.
Anti-rat thymocyte antibody-induced injury of glomerular mesangial cells is characterized initially by lysis (1 h) and is followed by proliferation (beginning at 3 to 4 days), with resolution that can include a focal increase in mesangial matrix (by 28 days). Chronic administration (every 12 h) of heparin (anticoagulant or nonanticoagulant) resulted in a decrease in antibody-induced mesangial cell proliferation, which, in turn, was associated with a decrease in the size and number of areas of focal mesangial matrix increase. The effect could not be attributed to the effect of heparin on complement, to alterations in the small numbers of la-positive cells that characterize the lesion, or to binding of antibody to glomeruli. The beneficial effects of heparin in reducing mesangial cell proliferation, with a subsequent reduction in matrix increase, suggest that mesangial cell responses are a major element in the development of at least some forms of glomerulosclerosis. The possible mechanisms by which these effects of heparin may be achieved are discussed. 相似文献