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51.
Three-dimensional ultrasonography in the first trimester of human pregnancy   总被引:1,自引:1,他引:1  
Our purpose was to visualize normal embryonal and fetal surface anatomical structures in the first trimester of human pregnancy by use of three-dimensional ultrasonography with a specially developed abdominal three-dimensional transducer. Four embryos and 31 fetuses of 8-13 weeks gestation were studied with a specially-developed abdominal three-dimensional transducer (3.5 MHz). This imaging system can provide conventional two-dimensional ultrasonography images and can also generate, within seconds, high-quality three-dimensional images in the surface and transparent mode with no need for an external workstation. The percentage of surface anatomical structures visualized at each gestational age interval using two-dimensional and three-dimensional ultrasonography is presented. Head and trunk were depicted in all cases. The number and the clarity of visualization of face, upper and lower extremities, hand, and foot increased with advancing gestation. The free loop of the umbilical cord was depicted in most cases. The number of depictions of abdominal cord insertion, midgut herniation, and yolk sac decreased with the increase of gestation. Genitals could not be identified in the first trimester. The ability to view some surface anatomical structures (face, hand, and foot) was better with three-dimensional ultrasonography than with two-dimensional ultrasonography. Three-dimensional ultrasonography provides a novel means for visualization of surface anatomical structures of the embryo and early fetus. These results suggest that three-dimensional ultrasonography can become an important modality in future embryological and early fetal research and in detection of embryonic and fetal developmental disorders in the first trimester of pregnancy.   相似文献   
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A clearance kinetic study of intravenously administered 125I-labeled aggregated human IgG (125I-AHIgG) from the circulation and its distribution in various organs was performed weekly during the course in a model of experimental immune complex glomerulonephritis which was induced in rats immunized 8 weeks previously with 6 times a week administration of 2 mg of bovine serum albumin (BSA) for 4 weeks from week 8 to 12. The removal rates of the injected 125I-AHIgG from the circulation were retarded in nonproteinuric rats of week 9 and 10, at almost every checked point (p-value was <0.01). The clearance in those rats with severe proteinuria returned to the level of the control and of rats in week 8. The distribution of 125I-AHIgG in the liver 4 hours after the administration revealed a considerable decrease in non-overt proteinuric rats of weeks 9, 10, and 11. A similar tendency of decreasing depositions of the radioactivity was shown in the spleen at each 4 hours. In contrast, the uptakes in the kidney and lung at the final week of 12 were larger. Delayed clearance from the circulation and a decreasing handle of the injected macromolecule in the liver and possibly in the spleen may suggest the presence of some impairment of the MPS function in the course of this experimental glomerulonephritis.  相似文献   
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A calcia base investment has high stability even with melted titanium and, therefore, can produce an excellent titanium casting. In this study, titanium powder was distributed to a calcia base investment as an expanding agent, and the firing temperature of the mold was controlled at 800 degrees C. The calcia base investment with 6.1% wt titanium powder expanded 1.7% during 2 h heating at 800 degrees C. The marginal discrepancies between the die and the titanium crown were improved by the addition of the titanium powder to the investment. The mean thickness of the cement layer between the epoxy teeth and the crown using 6.1% wt titanium powder content was from 40-80 microns.  相似文献   
56.
A rapid method for detecting barbiturates in serum using EI-SIM   总被引:2,自引:0,他引:2  
A simple and rapid method for analysis of barbiturates in serum has been developed. In order to extract and clean barbiturates in serum, a separation column packed with Extrelut and Florisil was used, and the eluate was directly analyzed by means of electron impact selected ion monitoring (EI-SIM). Selected ions used were base peak ions of 10 barbituartes, and the internal standard used was allobarbital or secobarbital. The calibration curves were linear over the range 0.5–5 ng. Extraction of replicate serum samples containing 20 g/1.5 ml and 5 g/1.5 ml resulted in a recovery of 87.2–105.2% and 81.6–104.6%, respectively, with the exception of phenobarbital, which was 151.9% and 172.1%, respectively. Secobarbital was also analyzed in the serum of 13 patients who had been given secobarbital intravenously. In 3 out of 10 cases, Secobarbital levels greater than 1 g/ml were detected more than 72 h after administration. This method seems to have possibilities for clinical use.Paper presented at the 2nd International Symposium ADVANCES IN LEGAL MEDICINE, Berlin, Germany, August 30–September 1, 1993  相似文献   
57.
We analyzed association between p53 and/or Rb expression and clinicopathologic variables or Ag-NOR counts, and then ascertained whether p53 and/or Rb expression would be useful for estimating prognosis in 81 breast cancer patients. Positive p53 expression was significantly associated with post-menopausal status, axillary lymph node metastases and Ag-NOR counts, whereas low level Rb expression was significantly associated with tumor size. Moreover, the combination of p53 and Rb expression was significantly associated with Ag-NOR counts, although there was no significant association between p53 and Rb expression. In the univariate study, p53 expression as well as age and axillary lymph node metastases were significantly associated with survival, whereas Rb expression was not. In the multivariate study, p53 and/or Rb expression did not provide independent prognostic information, although axillary lymph node metastases was an important factor affecting survival. Our findings suggest that p53 and/or Rb expression may reflect tumor proliferation of breast cancer, but the prognostic value of such assays is limited.  相似文献   
58.
Although breast conserving treatment (BCT) has become the standard therapy for early breast cancer, breast removal is still recommended for patients with a tumor beneath the nipple or with Paget’s disease. We have employed transposition of a latissimus dorsi myocutaneous (LD-MC) flap after wide local excision of a tumor with the nipple-areola complex. A new nipple-areola complex was reconstructed on the LD-MC flap after breast irradiation. Utilizing reconstructive techniques, BCT will likely become the treatment of choice for more patients with early breast cancer.  相似文献   
59.
Gelatinase A is an enzyme capable of cleaving soluble -amyloid protein (AP), and may function as an -secretase to produce secretory forms of amyloid precursor protein. We examined gelatinase A immunoreactivity in the brains and posterior roots of neurologically normal, lacunar stroke, Alzheimer disease (AD), amyotrophic lateral sclerosis, progressive supranuclear palsy and myasthenia gravis cases. The gelatinase A antibody stained only microglial cells in the white matter in all the brain tissues. In AD brain, the reactive microglia located in the center of classical senile plaques, as well as in other microglial cells in the gray matter, showed no immunoreactivity. Gelatinase A in white matter microglial cells may play a role in preventing local deposition of AP. In the posterior root, Schwann cells had positive immunoreactivity. As with other metalloproteases, gelatinase A in Schwann cells may play an antiproliferative role.  相似文献   
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