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501.
Peripheral blood hematopoietic progenitors (PBHP) are capable of colony growth in vitro. The effect of stem cell factor (SCF), interleukin-6 (IL-6), and basic fibroblast growth factor (bFGF) on myeloid colony proliferation of PBHP was determined. PBHP purified by positive selection with CD34-specific antibody were plated in semisolid agarose with reported plateau doses of interleukin-3 (IL-3), granulocyte- macrophage colony-stimulating factor (GM-CSF), and granulocyte colony- stimulating factor (G-CSF) to enhance myeloid colony growth. Experiments then were done to examine colony growth in response to SCF or with SCF and bFGF and/or IL6. SCF alone in the absence of any other growth factors did not support colony growth. SCF at a determined optimum concentration of 100 ng/mL added to the combination of IL-3, GM- CSF, and G-CSF enhanced colony growth and size relative to proliferation in response to the latter three factors alone (from 78 to 188 total colonies/10(4) PBHP plated and from 10 to 93 large [> 200 cells] colonies/10(4) PBHP plated). Furthermore, addition of bFGF and/or IL-6 to the combination of optimum concentrations of SCF, IL-3, GM-CSF, and G-CSF further enhanced colony number and size in a dose- dependent fashion. Using the optimum combination of all growth factors, we determined that the number of myeloid colony-forming PBHP in whole blood was similar between individuals at about three colonies per milliliter whole blood. We conclude that progenitors capable of responding to the early-acting growth factor, SCF, are represented in PBHP and that the number of circulating myeloid colony-forming PBHP is likely a regulated parameter that may have an important biologic function. 相似文献
502.
503.
Endometriosis detection by US with laparoscopic correlation 总被引:1,自引:0,他引:1
Endometriosis is a common cause of female infertility. It may affect as many as 40% of infertile women and may be the sole contributing factor to infertility in 15%. A study was undertaken to determine the usefulness of the routine pelvic ultrasound (US) examination in the detection of endometriosis by correlating pelvic US findings with laparoscopic findings in 85 patients who underwent both examinations. Forty-eight patients (56.5%) had no laparoscopic evidence of endometriosis, and 37 patients (43.6%) had endometriosis. Eight of the patients had abnormal sonograms; of these patients, only four had sonographic abnormalities that corresponded to laparoscopically identified endometriosis. Thus, US was successful in detecting endometriosis in only four (10.8%) of 37 patients. US is neither sensitive nor specific in diagnosing endometriosis. Furthermore, we believe that US does not have a significant role in the diagnosis or management of endometriosis in patients in whom a pelvic mass or other obvious pelvic abnormality is not suspected. 相似文献
504.
In 261 infants with vomiting, 11 duodenal abnormalities were diagnosed with fluid-aided ultrasound (US). These abnormalities included duodenal obstruction, malrotation with and without associated volvulus, incomplete rotation, and duodenal stenosis. US was the initial modality used in the evaluation of vomiting in these neonates and young infants. The overall sensitivity and specificity of fluid-aided US evaluation of duodenal abnormalities were 100% and 99%, respectively. (Workup bias limits the reliability of these figures.) Fluid-aided US examination of the stomach and duodenum provided a dynamic view of duodenal rotation and anatomy, and at the very least provided a method of triaging those infants who may require surgery, upper gastrointestinal series, or follow-up US to make a definitive diagnosis. 相似文献
505.
Inflammation of the middle ear cleft is a disease of great interest from both clinical and radiologic points of view. The attic floor (tympanic diaphragm), the tympanic isthmus, and the aditus ad antrum play important roles in inflammatory processes of the middle ear cleft. The anatomy of the temporal bone at this level was examined by studying microdissections of 250 fresh temporal bones and reviewing over 1,000 high-resolution computed tomography (CT) scans of the temporal bones. The pertinent anatomy is described, and the role of the tympanic diaphragm and isthmus in determining the degree to which middle ear disease may progress is stressed. The appearances on CT scans of chronic otomastoiditis, tympanosclerosis, cholesterol granuloma, attic retraction pocket, and acquired cholesteatoma are reviewed and illustrated. 相似文献
506.
Fetal choroid plexus cysts: beware the smaller cyst 总被引:1,自引:0,他引:1
Perpignano MC; Cohen HL; Klein VR; Mandel FS; Streltzoff J; Chervenak FA; Goldman MA 《Radiology》1992,182(3):715
507.
精胺广泛存在于动物组织和体液中,它在生殖过程中的作用还存在着很大的争议,作者综述了这些研究成果,并对其今后的发展动态作了展望. 相似文献
508.