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21.
A case of low-grade angiosarcoma arising in the skin of a breast previously irradiated for breast carcinoma is reported. Initially, an asymptomatic breast mass was detected. Excisional biopsy and axillary lymph node dissection revealed a 1.5-cm infiltrating ductal carcinoma with 21 negative lymph nodes. The neoplasm was staged as T1, N0, M0. The patient was entered in a research protocol and was treated with high-dose external beam (4,860 rad) and iridium implant (1,860 rad) irradiation. Seven years later the patient developed low-grade angiosarcoma of the breast skin. The lesion recurred following excision and eventually was treated by simple mastectomy. The patient never had evidence of lymphedema. Cutaneous angiosarcomas occurring as a complication of lumpectomy and radiation therapy for breast carcinoma are rare. In some reported cases the patients have had lymphedema, a known factor predisposing to angiosarcoma. Furthermore, almost all cases previously reported have been high grade. This case suggests that radiation therapy for breast carcinoma may also be complicated by low-grade angiosarcoma. 相似文献
22.
George Z Rassidakis Georgios V Georgakis Mauricio Oyarzo Anas Younes L Jeffrey Medeiros 《Modern pathology》2004,17(8):946-953
c-Kit receptor (CD117) is expressed by erythroid, megakaryocytic, and myeloid precursors and mature mast cells and has been reported to be expressed in CD30+ lymphomas such as Hodgkin's disease and anaplastic large-cell lymphoma. Imatinib mesylate, a well-established inhibitor of bcr-abl tyrosine kinase, and currently used for the treatment of patients with chronic myeloid leukemia, also inhibits c-kit receptor kinase activity. In view of the possible use of imatinib as experimental therapy for patients with c-kit-positive tumors, we assessed c-kit expression in CD30+ cell lines and lymphomas. The cell lines were assessed using multiple methods (RT-PCR, flow cytometry, and Western blot). c-Kit expression was also immunohistochemically assessed in 168 CD30+ lymphomas including 87 classical Hodgkin's disease, 63 anaplastic large-cell lymphoma, and 15 cutaneous anaplastic large-cell lymphoma. We also studied 18 cases of lymphomatoid papulosis, a CD30+ lesion closely related to cutaneous anaplastic large-cell lymphoma. Neither c-kit mRNA nor protein was detected in any of the cell lines assessed. Furthermore, treatment with imatinib did not inhibit proliferation of cell lines in vitro. Using immunohistochemistry, only one of 183 (0.5%) lesions was positive for c-kit, the positive case being an ALK-negative anaplastic large-cell lymphoma. Our data demonstrate that expression of c-kit receptor is exceedingly rare among CD30+ lymphomas and lymphomatoid papulosis, suggesting that c-kit receptor is unlikely to be an appropriate target for therapeutic options such as imatinib in patients with these tumors. 相似文献
23.
Roderik Metz Gino MMJ Kerkhoffs Egbert-Jan MM Verleisdonk Geert J van der Heijden 《BMC musculoskeletal disorders》2007,8(1):108
Background
We present the design of an open randomized multi-centre study on surgical versus conservative treatment of acute Achilles tendon ruptures. The study is designed to evaluate the effectiveness of conservative treatment in reducing complications when treating acute Achilles tendon rupture. 相似文献24.
C L Santos B A Medeiros R C Palheta-Junior G M Macedo M A Nobre-e-Souza L E A Troncon A A Santos M H L P Souza 《Neurogastroenterology and motility》2007,19(3):225-232
We evaluated the effects of cyclooxygenase-2 (COX-2) selective inhibitors, COX-1 selective inhibitor, or COX non-selective inhibitor on gastric emptying and intestinal transit of liquids, and evaluated the effect of a COX-2 selective inhibitor on gastric tonus (GT). Male Wistar rats were treated per os with saline (control), rofecoxib, celecoxib, ketorolac, rofecoxib + ketorolac, celecoxib + ketorolac, or indomethacin. After 1 h, rats were gavage-fed (1.5 mL) with the test meal (5% glucose solution with 0.05 g mL(-1) phenol red) and killed 10, 20 or 30 min later. Gastric, proximal, medial or distal small intestine dye recovery (GDR and IDR, respectively) were measured by spectrophotometry. The animals of the other group were treated with i.v. valdecoxib or saline, and GT was continuously observed for 120 min using a pletismomether system. Compared with the control group, treatment with COX-2 inhibitors, alone or with ketocolac, as well as with indomethacin increased GDR (P < 0.05) at 10-, 20- or 30-min postprandial intervals. Ketorolac alone did not change the GDR, but increased the proximal IDR (P < 0.05) at 10 min, and decreased medial IDR (P < 0.05) at 10 and 20 min. Valdecoxib increased (P < 0.01) GT 60, 80 and 100 min after administration. In conclusion, COX-2 inhibition delayed the gastric emptying of liquids and increased GT in rats. 相似文献
25.
P Iranzo MM Alsina I Martínez-De Pablo S Segura JM Mascaró C Herrero 《Journal of the European Academy of Dermatology and Venereology》2007,21(7):902-907
BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris. 相似文献
26.
Furtado de Medeiros Charles Angotti MSc Luccas George Carchedi PhD 《Dermatologic surgery》2005,31(12):1685-1694
BACKGROUND: Patients with varicose veins seek medical assistance for many reasons, including esthetic ones. The development of suitable and more flexible instruments, along with less invasive techniques, enables the establishment of new therapeutic procedures. OBJECTIVE: To compare endovenous great saphenous vein photocoagulation with an 810 nm diode laser and the conventional stripping operation in the same patient. METHODS: Twenty patients selected for operative treatment of primary great saphenous vein insufficiency on duplex scanning were assigned to a bilateral random comparison. In all cases, both techniques were performed, one on each lower limb. Clinically, evaluation was assessed on the seventh, thirtieth, and sixtieth postoperative days. Patients underwent examination with duplex ultrasonography and air plethysmography during the follow-up. RESULTS: Patients who received endovenous photocoagulation presented with the same pain but fewer swellings and less bruising than the stripping side. Most patients indicated that the limb operated on by laser received more benefits than the other. There was only one recanalization and no adverse effects. The venous filling time showed better hemodynamics in both techniques. CONCLUSION: The endovenous great saphenous vein photocoagulation is safe and well tolerated and presents results comparable to those of conventional stripping. 相似文献
27.
D Mahalanabis H Ashraf MM Rahman GJ Fuchs 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1113-1115
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1 ) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea. 相似文献
28.
Role of beta-lactamase in expression of resistance by methicillin-resistant Staphylococcus aureus. 总被引:4,自引:2,他引:2
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Of 27 unique clinical isolates of methicillin-resistant Staphylococcus aureus, only 4 were homogeneously resistant, and all 4 produced little or no beta-lactamase. Among heterogeneously resistant strains, those most resistant to beta-lactam antibiotics produced the most beta-lactamase. Similar genes may regulate production of the low-affinity penicillin-binding protein and beta-lactamase. 相似文献
29.
30.
Cardiac ultrastructural and functional characteristics were determined in copper-depleted and copper-repleted rats. Male weanling rats were randomized into five groups that were fed either copper-adequate or copper-deficient diets. After 5 wk, one group fed each diet was studied to obtain baseline values. At this time, one copper-adequate postweanling group continued to receive the adequate diet as control, one deficient postweanling group was fed the adequate diet to evaluate the effect of copper repletion and one postweanling adequate group was fed the deficient diet to evaluate copper depletion in relatively older rats. These dietary treatments were continued for six additional weeks. Copper-depleted rats of both ages exhibited significant cardiac ultrastructural pathology and electrocardiogram abnormalities and the postweanling copper-depleted rats exhibited these abnormalities in the absence of hypertrophy and anemia. Increased mitochondrial volume density, disarranged cristae, and nonaligned myofibrils with disturbances at Z-bands were displayed. Additionally, all copper-depleted rats demonstrated fragmented basal laminae at capillary-myocyte interface. Increased QRS amplitude and notching and greater QT intervals were displayed. Copper-repleted rats exhibited some, but not total, reversal of these abnormalities. These results suggest that capillary-myocyte interface changes may play an important role in the developing pathology of copper depletion. 相似文献