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71.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
72.
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.  相似文献   
73.
Public awareness of infectious diseases has focused attention on the prevention of nosocomial disease. Difficulties in sterilizing impressions have led to chemical disinfection as an alternative. Recent literature indicated a lack of consensus between researchers about distortion caused by disinfection. A polysulfide, polyether, and vinyl polysiloxane were disinfected by immersion in iodophor, sodium hypochlorite, and glutaraldehyde. Distortion was evaluated by use of a stainless steel die (ADA specification No. 19). Linear dimension variations after disinfection were clinically insignificant.  相似文献   
74.
Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day.  相似文献   
75.
This study investigated the effect of cement film thickness on the tensile bond strength of a prosthodontic adhesive. Rexillium III alloy cylinders were bonded end-to-end with Panavia Opaque adhesive cement and film thicknesses of 20, 50, 80, 110, 140, and 200 microns were evaluated. The specimens were thermocycled for 24 hours (1080 cycles) between 5 degrees and 60 degrees C, stored for 30 days at 37 degrees C, and the mean bonds for tensile strength, including the mode of failures, were recorded. Statistical analysis revealed significant differences, but the strongest bond strengths were recorded for the 80 microns cement film thickness.  相似文献   
76.
The acceptance of the semiallogeneic fetus within the maternal environment requires tolerance mechanisms not fully characterized yet. Normal pregnancy is known to be associated with a Th2 profile. Furthermore, T-regulatory cells were proposed to regulate the Th2/Th1 balance at early stages of pregnancy. Treg may avoid the shift to a Th1 profile preventing miscarriage. Accordingly, spontaneous abortion is characterized by a Th1 dominance and diminished levels of Tregulatory cells (Treg). The major aim of the present work was to investigate if pre-eclampsia, a late immunological complication of pregnancy, is characterized by similar hallmarks. Therefore, we measured the surface antigens CD4, CD25, CD8, CTLA4 (as well as the secretion of IL-10) in peripheral blood from patients suffering from pre-eclampsia (n = 8) and age-matched patients undergoing normal pregnancies (n = 9) by 4-colour flow-cytometry. We were not able to find any significant differences in the levels of CD4+, CD25+, CD8+, CTLA4, CD4+/CD25+, CD4+/CD25bright, CD4+/CTLA4, CD25+/CTLA4, CD4+/CD25+/CTLA4, CD8+/CD25+, CD8+/CTLA4 or CD8+/CD25+/CTLA4 cell subsets. Our data suggest that Treg may not participate in the onset of pre-eclampsia and suggest other regulatory mechanisms during late pregnancy.  相似文献   
77.
A technique has been presented to simplify the fabrication of multiple direct post and core patterns. When combined with techniques for indirect provisional restorations, this technique merely requires the fabrication of an additional plastic template to form the direct core patterns.  相似文献   
78.
79.
The effect of porcelain veneer opacity on the resultant shade of a veneer/substrate system was subjectively evaluated. Three groups of porcelain discs were fabricated using shade A1 Ceramco G veneer porcelain diluted with 0%, 25%, or 50% translucent porcelain. The discs were luted to a shade C4 substrate using an untinted composite resin luting agent. Clinicians were instructed to match samples with a custom and a commercial shade guide, and to sort veneers into groups of similar shade. The Farnsworth-Munsell 83 Hue test was used to measure the clinicians' color vision. Results indicated that the participants were unable to distinguish any difference between veneer groups (kappa = 0.33). Shade C2 was the predominant shade chosen for all groups. All veneers provided some masking of the underlying substrate. Varying the percentage of translucent porcelain had little effect on the final shade assessment.  相似文献   
80.
从平贝母茎叶中分离的平贝啶甙的结构   总被引:2,自引:0,他引:2  
本文报道自平贝母(Fritillaria ussuriensis Maxim)的地上茎叶中分得一种新的甾体生物碱甙,定名为平贝啶甙(pingbeidinoside),mp 242~243.2℃[a]D25+6.9°(c 0.145,MeOH)。经IR,MS,1HNMR和13CNMR谱解析,推定其结构为3β,16α,20-三羟基-Δ5-22,26-缩亚胺胆甾烷-25-O-α-D-葡萄糖甙。  相似文献   
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