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71.
Morphological analysis of degeneration and regeneration of syncytiotrophoblast in first trimester placental villi during organ culture 总被引:3,自引:1,他引:3
We have recently shown using dansyl-L-lysine exclusion studies that the
release of human chorionic gonadotrophin (HCG) in conjunction with L-
lactate dehydrogenase (LDH) from first trimester villi during organ culture
is symptomatic of syncytiotrophoblast degeneration. The purpose of this
study was to examine chorionic villi at the ultrastructural level in order
to determine events occurring during organ culture. The tissue was sampled
after 0, 24, 48 and 120 h in culture and processed for electron microscopy.
In addition to confirming the previously recorded syncytial degeneration,
the electron micrographs showed clearly the generation of a new
syncytiotrophoblast layer. The new layer, derived from differentiating
cytotrophoblast cells, was largely formed by 48 h and was maintained for at
least 120 h in culture. This study demonstrates a model which provides an
opportunity to study the differentiation of cytotrophoblast cells whilst
they retain their anatomical relationships within the villous structure.
相似文献
72.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
73.
74.
The effect of barium on blood in the gastrointestinal tract 总被引:2,自引:0,他引:2
75.
The effect of atracurium or fazadinium on intra-ocular pressure. A comparative study during induction of general anaesthesia 总被引:2,自引:0,他引:2
M.P. Tattersall ME BS FFARCS Consultant N. J. Manus MB BS FFARCS Registrar D.M. Jackson FFARCS DObstRCOG Consultant 《Anaesthesia》1985,40(8):805-807
The effect of atracurium 0.6 mg/kg (group A; n = 11) and fazadinium 1 mg/kg (group F; n = 11) on intraocular pressure (IOP) was investigated in 22 patients during induction of anaesthesia with thiopentone 4 mg/kg and fentanyl 0.015 mg/kg. IOP was significantly reduced (p less than 0.01) in all patients following induction of anaesthesia. Intubation produced a rise in IOP in all patients but this was not statistically significant and remained below pre-induction values. The changes were similar in each group. Both of these neuromuscular blockers appear suitable relaxants to use for intraocular surgery. 相似文献
76.
77.
Casanueva FF Molitch ME Schlechte JA Abs R Bonert V Bronstein MD Brue T Cappabianca P Colao A Fahlbusch R Fideleff H Hadani M Kelly P Kleinberg D Laws ED Marek J Scanlon M Sobrinho LG Wass JAH Giustina A 吴哲褒 张亚卓 《中华神经外科杂志》2008,24(8)
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异. 相似文献
78.
Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function. 相似文献
79.
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia. 相似文献
80.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献