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排序方式: 共有4419条查询结果,搜索用时 859 毫秒
41.
Enrique Teran Carlos Escudero Sandra Vivero Armando Enriquez Andres Calle 《Hypertension in pregnancy》2004,23(3):303-308
OBJECTIVE: To investigate the intraplatelet cyclic guanosine-3',5'-monophosphate (cGMP) levels during normal pregnancy and preeclampsia. STUDY DESIGN: Pregnant women (n = 15), women with preeclampsia (n = 15), and nonpregnant, normotensive women (n = 15) were included. Intraplatelet cyclic guanosine-3',5'-monophosphate levels were measured by an enzyme-linked immunosorbent assay. RESULTS: Intraplatelet cGMP levels were significantly different among all groups (p < 0.02). The values were higher in normal pregnant women (mean 19.8 SD 2.6 fmol/10(5) platelets) in comparison to nonpregnant women (mean 7.6 SD 0.3 fmol/10(5)platelets; p = 0.001) and women with preeclampsia (mean 11.3 SD 1.8 fmol/10(5) platelets; p = 0.05). Plasma nitric oxide levels did not reveal differences between all groups. CONCLUSIONS: The results of this study in a high-risk Andean population demonstrated that intraplatelet cyclic guanosine-3',5'-monophosphate levels are decreased during preeclampsia compared to normal pregnancy, suggesting a lack in action of nitric oxide. 相似文献
42.
Melina Verso Giancarlo Agnelli Sergio Bertoglio Franco C Di Somma Francesco Paoletti Walter Ageno Mario Bazzan Pasquale Parise Roberto Quintavalla Emanuele Naglieri Armando Santoro Davide Imberti Mariella Sorarù Stefano Mosca 《Journal of clinical oncology》2005,23(18):4057-4062
PURPOSE: The extent of venous thromboembolism (VTE) associated with central vein catheters (CVC) in cancer patients remains unclear. The aim of this study was to evaluate the efficacy and safety of the low molecular weight heparin, enoxaparin, in the prevention of VTE. PATIENTS AND METHODS: In a multicenter, double-blind study, consecutive cancer patients scheduled for CVC insertion were randomly assigned to receive either subcutaneous enoxaparin 40 mg once a day or placebo. Treatment was started 2 hours before CVC insertion and continued for 6 weeks. The primary end points of the study were deep vein thrombosis (DVT), confirmed by venography of the CVC limb performed 6 weeks after randomization, or clinically overt pulmonary embolism, confirmed by objective testing during the study drug administration. Patients were assessed for bleeding complications. RESULTS: Three hundred eighty-five patients were randomized, of which 321 (83.4%) underwent venography. A venography was adequate for adjudication in 155 patients in each treatment group. A DVT was observed in 22 patients (14.1%) treated with enoxaparin and in 28 patients (18.0%) treated with placebo, corresponding to a relative risk of 0.78 (95% CI, 0.47 to 1.31). No major bleeding occurred. Five patients (2.6%) in the enoxaparin group and two patients (1.0%) in the placebo group died during the treatment period. CONCLUSION: In this study, no difference in the rate of CVC-related VTE was detected between patients receiving enoxaparin and patients receiving placebo. The dose of enoxaparin used in this study proved to be safe. Clinical trials evaluating higher enoxaparin doses could optimize the efficacy of this agent for this indication. 相似文献
43.
Allogeneic stem-cell transplantation may overcome the adverse prognosis of unmutated VH gene in patients with chronic lymphocytic leukemia. 总被引:2,自引:0,他引:2
Carol Moreno Neus Villamor Dolors Colomer Jordi Esteve Rodrigo Martino Josep Nomdedéu Francesc Bosch Armando López-Guillermo Elías Campo Jorge Sierra Emili Montserrat 《Journal of clinical oncology》2005,23(15):3433-3438
PURPOSE: To investigate whether allogeneic stem-cell transplantation (allo-SCT) may overcome the negative impact of unmutated VH genes in the outcome of patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: We analyzed the outcome of patients who underwent SCT according to their VH mutational status. RESULTS: Thirty-four patients (14 allo-SCT and 20 autologous SCT [auto-SCT]) presented unmutated VH genes and 16 patients presented mutated VH genes (nine allo-SCT and seven auto-SCT). Tumoral burden pre-SCT was significantly higher in the allo-SCT patients independent of the VH mutational status. The risk of relapse was significantly higher after auto-SCT (5-year risk, 61%; 95% CI, 44% to 84%) than after allo-SCT (5-year risk 12%, 95% CI, 3% to 44%; P < .05). In the unmutated group, 13 of 20 auto-SCT and two of 14 allo-SCT patients experienced disease progression, with a risk of relapse at 5 years of 66% (95% CI, 48% to 93%) v 17% (95% CI, 5% to 60%), respectively (P = .01). CONCLUSION: These results show that allo-SCT may overcome the unfavorable effect of unmutated VH genes in patients with CLL. 相似文献
44.
American Society of Clinical Oncology guideline recommendations for sentinel lymph node biopsy in early-stage breast cancer. 总被引:28,自引:0,他引:28
Gary H Lyman Armando E Giuliano Mark R Somerfield Al B Benson Diane C Bodurka Harold J Burstein Alistair J Cochran Hiram S Cody Stephen B Edge Sharon Galper James A Hayman Theodore Y Kim Cheryl L Perkins Donald A Podoloff Visa Haran Sivasubramaniam Roderick R Turner Richard Wahl Donald L Weaver Antonio C Wolff Eric P Winer 《Journal of clinical oncology》2005,23(30):7703-7720
PURPOSE: To develop a guideline for the use of sentinel node biopsy (SNB) in early stage breast cancer. METHODS: An American Society of Clinical Oncology (ASCO) Expert Panel conducted a systematic review of the literature available through February 2004 on the use of SNB in early-stage breast cancer. The panel developed a guideline for clinicians and patients regarding the appropriate use of a sentinel lymph node identification and sampling procedure from hereon referred to as SNB. The guideline was reviewed by selected experts in the field and the ASCO Health Services Committee and was approved by the ASCO Board of Directors. RESULTS: The literature review identified one published prospective randomized controlled trial in which SNB was compared with axillary lymph node dissection (ALND), four limited meta-analyses, and 69 published single-institution and multicenter trials in which the test performance of SNB was evaluated with respect to the results of ALND (completion axillary dissection). There are currently no data on the effect of SLN biopsy on long-term survival of patients with breast cancer. However, a review of the available evidence demonstrates that, when performed by experienced clinicians, SNB appears to be a safe and acceptably accurate method for identifying early-stage breast cancer without involvement of the axillary lymph nodes. CONCLUSION: SNB is an appropriate initial alternative to routine staging ALND for patients with early-stage breast cancer with clinically negative axillary nodes. Completion ALND remains standard treatment for patients with axillary metastases identified on SNB. Appropriately identified patients with negative results of SNB, when done under the direction of an experienced surgeon, need not have completion ALND. Isolated cancer cells detected by pathologic examination of the SLN with use of specialized techniques are currently of unknown clinical significance. Although such specialized techniques are often used, they are not a required part of SLN evaluation for breast cancer at this time. Data suggest that SNB is associated with less morbidity than ALND, but the comparative effects of these two approaches on tumor recurrence or patient survival are unknown. 相似文献
45.
Anabel Pérez-Gómez Armando García-Rodríguez Kevin J James Amaia Ferrero-Gutierrez Antonello Novelli M Teresa Fernández-Sánchez 《Toxicological sciences》2004,80(1):74-82
Diarrhetic shellfish poisoning (DSP) toxins of algal origin are frequent contaminants of coastal waters and seafood. The potential risk for human health due to the continuous presence of these toxins in food has not been clearly established. We have used cerebellar primary cultures to investigate the effects of the DSP toxin dinophysistoxin-2 (DTX-2) on central nervous system neurons and glial cells. Exposure to DTX-2 produced neurotoxicity at concentrations starting at 2.5 nM, characterized first by disintegration of neurites and later by cell death. DTX-2-induced neurodegeneration required long exposures (at least 20 h), involved DNA fragmentation and condensation and fragmentation of chromatin, typical hallmarks of apoptosis, and required the synthesis of new proteins. The concentration that reduced by 50% the maximum neuronal survival after 24 h exposure to DTX-2 (EC50(24)) was approximately 8 nM. Morphology and viability of glial cells remained unaffected up to at least 15 nM DTX-2. Higher concentrations of the toxin caused strong shrinkage of glial cell bodies and retraction of processes, and a significant reduction of glial cell viability. Glial toxicity by DTX-2 involved typical apoptotic condensation and fragmentation of chromatin. Compared to neurons, the effect on glial cells was a much shorter process, and extensive glial degeneration and death occurred after 7 h exposure to DTX-2 (EC50(7) approximately 50 nM; EC50(24) approximately 30 nM). Although further experiments are needed to confirm these toxic actions in vivo, our in vitro data suggest that chronic exposure to amounts of DSP toxins below the current safety regulatory limits may represent a risk for human health that should be taken into consideration. 相似文献
46.
Armando Pérez-Rangel José Manuel Hernández Araceli Castillo-Romero Lilián Yépez-Mulia Rafael Castillo Francisco Hernández-Luis Benjamín Nogueda-Torres Juan Pedro Luna-Arias Gerardo Radilla Gloria León-Avila 《Parasitology research》2013,112(9):3251-3257
In the present study, we evaluated the effect of an albendazole (ABZ) derivative JVG9 on cultured Giardia intestinalis. To assess the JVG9 effects, we evaluated the tubulin cytoskeleton by confocal microscopy, and we found that the characteristic staining was modified. The scanning electron microscopy images revealed extremely damaged trophozoites and cyst-like cells. The confocal images revealed that this drug triggered the expression of cyst wall protein 1 and encystation. We also found that at low doses, AL triggered the encystation process too. 相似文献
47.
48.
Erica de Camargo Ferreira e Vasconcellos Maria Inês Fernandes Pimentel Cláudia Maria Valete-Rosalino Maria de Fátima Madeira Armando de Oliveira Schubach 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):361-362
We report a case of a 42 year-old female, who came to a leishmaniasis
reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis
lesion in the right forearm. Treatment with low-dose intramuscular meglumine
antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after
28 days, although with the development of generalized eczema. After 87 days, the
lesion worsened. Patient refused treatment with amphotericin B. MA was then
infiltrated in the lesion, in two sessions, resulting in local eczema, with bullae
formation; however, twenty days after, both the ulcer and eczema receded.
Intralesional administration of MA should be used carefully when previous cutaneous
hypersensitivity is detected. 相似文献
49.
V. Celentano E. Esposito S. Perrotta M.C. Giglio R. Tarquini G. Luglio 《Acta chirurgica Belgica》2013,113(6):417-420
Madelung disease is a rare disorder characterized by the presence of multiple, symmetric, nonencapsulated fatty accumulations diffusely involving the cheeks, the neck, the upper trunk, the shoulder girdle area, and the upper extremities. The cause of this syndrome is unknown, but it has been associated with alcoholism in 60% to 90% of patients. The long-term lipomatous deposits are often large and cosmetically deforming, and the upper aerodigestive tract and great veins may be compressed. We report the case of a man with MD, involving the cervical and upper dorsal regions, who underwent surgical treatment at our Department. 相似文献