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排序方式: 共有4958条查询结果,搜索用时 15 毫秒
991.
Microsomal sphingomyelin accumulation in thioacetamide-injured regenerating rat liver: involvement of sphingomyelin synthase activity 总被引:1,自引:0,他引:1
Miro-Obradors Maria-Jesus; Osada Jesus; Aylagas Hortensia; Sanchez-Vegazo Inmaculada; Palacios-Alaiz Evangelina 《Carcinogenesis》1993,14(5):941-946
The purpose of this work was to determine whether alterationsin the lipid composition of rat liver microsomal membranes existedduring thioacetamide-induced injury prior to the developmentof hepatic cancer and biochemical mechanisms involved. Ratswere injected intraperitoneally with (50 mg/kg body wt per day)thioacetamide or diluent for 8 days. Liver homogenates and microsomalmembranes from liver homogenates were obtained. Incorporationof [32P]orthophosphate into whole liver lipids and hepatic microsomallipids was evaluated 75 min after isotope administration. Thesedeterminations were made after two separate periods of treatment(3 and 8 days). Activity of sphingomyelin synthase was assayedin rat liver homogenates as well as in the purified microsomalfractions. Results demonstrated a maintenance of liver and hepaticmicrosomal contents of phosphatidylcholine during thioacetamide-inducedinjury even when the biosynthesis of this glycerophospholipidin both liver and their microsomal fractions appeared decreased.Also observed was a considerable increase of microsomal sphingomyelin,as well as an increased hepatic biosynthesis of sphingomyelincaused by thioacetamide treatment. The microsomal sphingomyelin/phosphatidylcholineradioactivity ratio significantly increased. Sphingomyelin synthaseactivity in liver homogenate appeared stimulated. In conclusion,our data are consistent with a thioacetamide-induced increasein microsomal sphingomyelin by a stimulation of sphingomyelinsynthase. Based on this and previous studies, accumulation ofsphingomyelin in the microsomal purified fraction is associatedwith the number of thioacetamide doses and is an early eventclearly detected prior to tumoral characteristics of hepatocytes. 相似文献
992.
Verrucous carcinoma is a rare variant of epidermoid carcinoma with distinct clinical and histopathologic features. To date, 31 cases have been reported in the cervix. They are typically slow-growing, locally invasive tumors with low potential for lymphatic metastasis and appear to be radioresistant. We report a case which is unusual in having endometrial and deep myometrial invasion. Electron microscopy, immunohistochemical stains, and DNA in situ hybridization studies failed to detect human papilloma virus particles but the oncogenic potential of the virus is not excluded. 相似文献
993.
Ramón Paniagua Alfonso Ramos Rosaura Fabian Jesús Lagunas Dante Amato 《Peritoneal dialysis international》2007,27(4):405-409
The increasing rates in incidence and prevalence of chronic kidney disease (CKD) are important challenges for health systems around the world, and are even more significant for undeveloped countries. In Mexico the prevalence of CKD seems to be similar to that in highly developed nations, with diabetes as the leading cause of CKD; however, human and economic resources seem to be insufficient for treatment needs. This is reflected in the unacceptably high mortality rates and in noncompliance with established standards and guidelines. Several measures need to be taken to improve this picture, such as more efficient programs for the prevention of obesity, diabetes, and hypertension. Organizing a national registry of patients with CKD is now a pressing need, as is a continuous search for additional funding and budgets to increase the number of qualified nephrologists and specialized nurses and to continue the much-needed research on CKD. 相似文献
994.
Gerardo A. Moreno-Arias MD Antonio Vilalta-Solsona MD José M. Serra-Renom MD Jesus Benito-Ruiz MD Juan Ferrando MD 《Dermatologic surgery》2002,28(5):402-404
BACKGROUND: Intense pulsed light (IPL) is an effective and safe method of hair removal. OBJECTIVE: To evaluate the clinical response of hairy grafts and flaps of different anatomic areas to an IPL source. METHODS: Four patients (three men, one woman; 17-72 years old) with hairy skin grafts (n = 2) or flaps (n = 2) were included. Donor skin areas included the forehead (n = 1), supraclavicular (n = 1), abdomen (n = 1), and groin (n = 1). Excisional surgery was performed because of basal cell carcinoma (BCC) of the nasal wall (n = 1), squamous cell carcinoma (SCC) of the forehead (n = 1), congenital nevus of the malar region (n = 1), and breast carcinoma (n = 1). The treatment was IPL with the following parameters: wavelength 695-755 nm, pulse width 3.8-4.5 msec, delay 20-30 msec, spot size 10 mm x 45 mm, fluence 38-42 J/cm2, and an interval of 4 weeks. A total of one to six treatment sessions were administered. RESULTS: A progressive decrease in terminal hair and delayed hair growth rate (more than 8 months) were observed in all the patients. Improvement of skin coarseness, pigmentation, and erythema was also observed in the graft and its periphery in one patient. Persistent erythema (more than 48 hours) was the only side effect, observed in one patient. CONCLUSION: IPL is an effective method to depilate hairy grafts and flaps. 相似文献
995.
996.
Norman D. Sundberg Johana P. Hadiyono Carl A. Latkin Jesus Padilla 《The journal of primary prevention》1995,15(4):361-376
To prevent mental illness and promote psychological health, developing countries might learn from demonstrated successes in other countries. This exploratory qualitative project involved interviewing 27 informants knowledgeable about both the United States and selected developing countries of Asia and South America. Informants reviewed five preventive programs shown to be effective in North America and then evaluated the programs as to their applicability in the other country. In general the programs were seen as not very transferrable, and in some cases not needed. Among transfer problems identified were funding, training, cultural traditions and higher priorities for other things in impoverished countries. The primary recommendation is that prevention programs be developed in other countries based on their needs and cultural characteristics and using indigenous human resources. Such programs could be informed by general principles and evaluation procedures developed in Western prevention programs. Informants noted that there are also important things for Americans to learn from the developing countries, such as family closeness and greater acceptance and relaxation about stresses of life. 相似文献
997.
Jesus R Alvarez Arlene Bardeguez Leslie Iffy Joseph J Apuzzio 《The journal of maternal-fetal & neonatal medicine》2007,20(12):853-857
OBJECTIVE: The objective of this study was to describe one center's five-year experience of the management of human immunodeficiency virus (HIV) positive gravidas with preterm premature rupture of the membranes (PPROM) not in labor at 相似文献
998.
Miguel A. Sanz M.D. Francisca López M.D. Maria L. Martínez Guillermo F. Sanz M.D. Jesus A. Martínez M.D. Guillermo Martín M.D. Miguel Gobernado M.D. 《Supportive care in cancer》1996,4(4):291-293
Three new cases ofBlastoschizomyces capitatus infection occurring in neutropenic patients with acute myeloblastic leukaemia are reported.B. capitatus was isolated from blood cultures in all patients. All three patients were treated with amphotericin B, but only one was cured from the infection. Our study confirms the emergence ofB. capitatus as an opportunistic agent of disseminated fungal infection in leukaemic patients. 相似文献
999.
1000.