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991.
992.
Epidermal growth factor (EGF) has been shown to modulate endometrial
differentiation in vivo and in vitro. Therefore, endometrial stromal cell
EGF receptors were characterized in intact endometrial stromal cells,
cultured in vitro. The methods used for characterization were flow
cytometry, binding and displacement studies, and gel electrophoresis
followed by autoradiography. In flow cytometry the histogram of labelled
stromal cells was identical to Caski cells, which served as a positive
control. EGF binding revealed the typical binding hierarchy for EGF
receptors. The Scatchard analysis showed a curvilinear plot with a
calculated dissociation constant of 0.36 nM for high affinity binding
sites. In autoradiography a band of approximately 170 kDa was visualized
corresponding to the known size of the EGF receptor. The intensity of this
band was increased by pretreatment of stromal cells with 10 nM progesterone
for 4 days. Furthermore, stimulation with progesterone led to an increase
in specific EGF binding activity of stromal cells by 21% compared to
control. These data indicate that intact stromal cells in monolayer culture
maintain specific EGF receptors, which are up-regulated by progesterone.
相似文献
993.
994.
Testicular cysts: US findings 总被引:2,自引:0,他引:2
Testicular cysts have been considered rare. However, of 307 men who underwent high-resolution ultrasonography (10 MHz) of the scrotum, 30 (9.8%) had testicular cysts. Thirty-three testes were involved, 23 with single cysts, eight with clusters of multiple tiny cysts, and two with more than one focus of cyst. One cyst was aspirated intraoperatively, and one cyst of the tunica albuginea was proved at surgery. Eighty cadaveric testes were scanned also, and cysts were found in one. In two cases, the pathologic report, reviewed retrospectively, failed to mention the cyst, but these cysts could have been overlooked. Further work is needed to determine when or if these testicular lesions need follow-up and what significance they have, if any. 相似文献
995.
E Hietanen H Bartsch J C Bereziat M Ahotupa A M Camus J R Cabral M Laitinen 《International journal of cancer. Journal international du cancer》1990,46(4):640-647
Male rats were fed, from weaning onwards, either 2, 12.5 or 25% sunflower seed oil (polyunsaturated fatty acids, PSA) or lard (saturated fatty acids, SFA) and from the age of 15 weeks subgroups were given N-nitrosodimethylamine (NDMA) for 30 weeks. Blood levels of lipids were assayed and during the study exhaled ethane was measured as an index of in vivo lipid peroxidation (LPO). At the age of 50 weeks, rats were killed and livers were analysed for tumours. PSA diets decreased plasma cholesterol and triglyceride concentrations vs. respective SFA diet; NDMA administration did not affect plasma cholesterol but enhanced triglyceride concentration. NDMA markedly enhanced LPO. An increase in dietary fat content from 2 to 25% enhanced ethane exhalation, more in rats fed PSA than the SFA diet. In the 25% PSA group, indomethacin in the diet strongly inhibited LPO. Prevalence of liver haemangiosarcomas increased from 42% to 80% (p less than 0.05) in NDMA-treated animals when PSA increased from 2 to 25%; in the group having a 25% PSA diet containing indomethacin, the NDMA-induced tumour incidence was reduced to 64%. In NDMA-treated rats fed SFA diets the prevalence of haemangiosarcoma increased from 43% (2% fat) to 67% (25% fat). The data show that NDMA modifies plasma lipids and increases LPO. The quantity and saturation degree of fats altered the frequency of chemically-induced tumours and modified LPO. As an index of free radical reactions, LPO may have an important role in carcinogenesis. Dietary fat thus appears to promote carcinogenesis through mechanisms that involve LPO. 相似文献
996.
The accumulation of technetium-99m diethylenetriamine pentaacetic acid (Tc-99m DTPA) in benign soft-tissue neurofibromatosis tumors is reported. In a series of 16 patients with clinical stigmata of neurofibromatosis, 28 sites of abnormal soft-tissue localization of the isotope observed scintigraphically were documented to be sites of soft-tissue tumor by clinical and/or radiographic (predominantly computed tomographic) correlations. The smallest lesion detected was a 1.5-cm subcutaneous neurofibroma. Normal physiologic nonrenal distribution of the Tc-99m DTPA was established by scintigraphic imaging of a control population. 相似文献
997.
998.
Ramos A Tanuri A Schechter M Rayfield MA Hu DJ Cabral MC Bandea CI Baggs J Pieniazek D 《Emerging infectious diseases》1999,5(1):65-74
We systematically evaluated multiple and recombinant infections in an HIV-infected population selected for vaccine trials. Seventy-nine HIV-1 infected persons in a clinical cohort study in Rio de Janeiro, Brazil, were evaluated for 1 year. A combination of molecular screening assays and DNA sequencing showed 3 dual infections (3.8%), 6 recombinant infections (7.6%), and 70 (88.6%) infections involving single viral subtypes. In the three dual infections, we identified HIV-1 subtypes F and B, F and D, and B and D; in contrast, the single and recombinant infections involved only HIV-1 subtypes B and F. The recombinants had five distinct B/F mosaic patterns: Bgag-p17/Bgag-p24/Fpol/Benv, Fgag-p17/Bgag-p24/Fpol/Fenv, Bgag-p17/B-Fgag-p24/Fpol/Fenv, Bgag-p17/B-Fgag-p24/Fpol/Benv, and Fgag-p17/B-Fgag-p24/Fpol/Fenv. No association was found between dual or recombinant infections and demographic or clinical variables. These findings indicate that dual and recombinant infections are emerging as an integral part of the HIV/AIDS epidemic in Brazil and emphasize the heterogenous character of epidemics emerging in countries where multiple viral subtypes coexist. 相似文献
999.
Hypovolemic shock in children: abdominal CT manifestations 总被引:2,自引:0,他引:2
The authors describe a "hypoperfusion complex," seen on abdominal computed tomography, which consists of marked, diffuse dilatation of the intestine with fluid; abnormally intense contrast enhancement of the bowel wall, mesentery, kidneys, and/or pancreas; decreased caliber of the abdominal aorta and inferior vena cava; and moderate to large peritoneal fluid collections. This complex was present in three patients less than 2 years of age and was associated with severe injury and a poor outcome. Recognition of this constellation of findings may help direct attention to the patient's serious hemodynamic abnormality as much as to individual organ defects. 相似文献
1000.
Ewaldo Bolivar de Souza Pinto M.D. Antonio Esau Ferraz de Almeida M.D. Antonio Francisco Knudsen M.D. Silvia Maria Fernandes S. de Andrade M.D. João Cabral de Medeiros M.D. 《Aesthetic plastic surgery》1987,11(1):213-222
This article presents a personal methodology for the surgical planning of abdominoplasties with the goal of obtaining the best aesthetic result with the minimum of scars. With a thorough physical examination, the abdomens are classified into different groups and surgery is planned accordingly. The authors use liposuction in association with dermolipectomy and introduce a new approach to treating supraumbilical muscle diastases. The results obtained have been good, with a smooth recovery and better scars. 相似文献