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11.
A triplet pregnancy in a 23-year-old woman was terminated at 15 weeks of gestation because of her severe hypertension, lung edema, and secondary hyperthyroidism. The pregnancy consisted of a hydatidiform mole with a 46,XY karyotype and two fetuses each with 46,XX and a 46,XY karyotype. To determine the zygosity and genetic origin of the mole and fetuses, PCR- and computer-assisted genotyping were performed at 27 CA-repeat marker loci that were distributed evenly over the genome. As a result, genotypes of the three pregnancy products were distinct from each other, indicating that the triplets were trizygotic. The mole lacked any maternal alleles but inherited both of the paternal alleles and/or one paternal allele in duplicate. This, along with the XY sex chromosome constitution, indicated that the mole resulted from dispermic androgenesis. The mother developed a persistent trophoblastic tumor thereafter.  相似文献   
12.
Evidence linking paclitaxel to cardiotoxicity arose from early Phase I trials in which continuous cardiac monitoring was performed because of the high incidence of major hypersensitivity reactions. A variety of cardiac manifestations have been reported, ranging from asymptomatic sinus bradycardia to fatal myocardial infarction. The following case report describes an acute myocardial infarction occurring shortly after paclitaxel therapy.  相似文献   
13.
PURPOSE: To determine the average abdominal entrance air kerma, low-contrast sensitivity, and spatial resolution in upper gastrointestinal tract fluoroscopy in the United States. MATERIALS AND METHODS: A random sample of fluoroscopic facilities was selected to be surveyed for the Nationwide Evaluation of X-ray Trends program. Measurements were performed by using a newly developed fluoroscopic phantom. The surveys were conducted by state radiation control personnel. RESULTS: Average air kerma rates 1 cm above the tabletop, free in air, were 43 mGy/min (n = 340). The rate increased to 64 mGy/min when a 1.6-mm-thick copper filter, which simulated the use of barium contrast medium, was added to increase attenuation. The average entrance air kerma, free in air, for radiographs was 3.4 mGy, and an average of 12 radiographs were obtained per examination. Of 352 facilities surveyed, 306 (87%) were able to resolve wire mesh with 20 or more lines per inch. Of 339 facilities for which percentage contrast could be calculated, 192 (57%) had minimum percentage contrast values of 4% or more. CONCLUSION: Spatial resolution for fluoroscopy is adequate for most of the facilities surveyed, but a substantial proportion of facilities could not visualize low-contrast test objects, which strongly suggests image quality problems.  相似文献   
14.
Urocanic acid (UCA) is a major chromophore for ultraviolet (UV) radiation in the skin. On UV exposure, the naturally occurring trans-isomer converts to the cis-isomer in a dose-dependent manner. Accumulating evidence indicates that cis-UCA acts as an initiator of the UV-induced suppression of certain skin immune functions. This immunomodulation is recognized as an important factor in the development of skin cancer. In this study, pigmentation and UCA isomers were measured in 29 patients with previous basal cell carcinoma (BCC), 23 patients with previous cutaneous malignant melanoma (MM), and 32 healthy controls. Measurements were performed on UV-exposed (forehead, upper back) and UV non-exposed (buttock) skin. No significant differences in pigmentation percentage, total UCA concentration, relative (%) or absolute (nmol/cm2) cis-UCA concentration were observed between the groups in any of the body sites studied. The net production of cis-UCA after irradiation with a single test UV dose was evaluated. The relative production of cis-UCA following irradiation was significantly higher in both cancer groups when compared with the control group, while no significant difference was found between the BCC and the MM patients.  相似文献   
15.
The anaerobic chytrid Piromyces sp. E2 lacks mitochondria, but contains hydrogen-producing organelles, the hydrogenosomes. We are interested in how the adaptation to anaerobiosis influenced enzyme compartmentalization in this organism. Random sequencing of a cDNA library from Piromyces sp. E2 resulted in the isolation of cDNAs encoding malate dehydrogenase, aconitase and acetohydroxyacid reductoisomerase. Phylogenetic analysis of the deduced amino acid sequences revealed that they are closely related to their mitochondrial homologues from aerobic eukaryotes. However, the deduced sequences lack N-terminal extensions, which function as mitochondrial leader sequences in the corresponding mitochondrial enzymes from aerobic eukaryotes. Subcellular fractionation and enzyme assays confirmed that the corresponding enzymes are located in the cytosol. As anaerobic chytrids evolved from aerobic, mitochondria-bearing ancestors, we suggest that, in the course of the adaptation from an aerobic to an anaerobic lifestyle, mitochondrial enzymes were retargeted to the cytosol with the concomitant loss of their N-terminal leader sequences.  相似文献   
16.
The possibility of obtaining antibodies to human hemoglobin and erythrocytes and their use for the detection of hidden blood in different biological fluids was studied. The test system, based on the reaction of coagglutination with the use of protein A of Staphylococcus aureus Cowan 1 and magnetic sorbent, is proposed.  相似文献   
17.
18.
Renal elimination of the bromosulfophthalein-glutathione conjugate (BSP-GSH) after its i.v. administration in the rat in vivo is negligible. In our study we wanted to establish whether the high albumin-binding of BSP-GSH constitutes the major restrictive factor toward the urinary excretion of the compound. The renal disposition of BSP-GSH was studied in the isolated rat kidney during perfusions with or without albumin in the perfusate. The urinary clearance of BSP-GSH in the absence of albumin was very low (< 60 microliters/min) as compared to the inulin clearance (approximately 300 microliters/min). This indicates that albumin-binding is not the major reason for the low urinary clearance of BSP-GSH. Addition of albumin to the perfusate further decreased the urinary excretion by 60%. BSP-GSH is metabolized by the kidney into two major metabolites: the cysteinylglycine conjugate and the di-glutathione conjugate. Both metabolites appear in perfusate, which suggests that BSP-GSH undergoes tubular (re-)uptake. The di-glutathione conjugate is further metabolized to the di-cysteinylglycine conjugate. The di-glutathione conjugate and the di-cysteinylglycine conjugate are the major urinary components and the urinary elimination of BSP-GSH may depend on their formation. Inhibition of gamma-glutamyl transpeptidase activity with acivicin largely prevented the degradation to the cysteinylglycine and dicysteinylglycine conjugates of BSP. The total rate of urinary excretion, however, was only slightly lowered by acivicin. Apparently, cleavage of the gamma-glutamyl moiety is not relevant for the total urinary elimination of BSP-GSH.  相似文献   
19.
Individuals with one aerodigestive tract malignancy have a high incidence of second primary aerodigestive tumors. The mechanism for this field effect has not been determined. We studied an individual with widespread dysplastic changes in the respiratory epithelium but no overt carcinoma. The entire tracheobronchial tree obtained at autopsy was embedded in paraffin, and bronchial epithelial cells were isolated by microdissection. DNA extracted from the microdissected cells was analyzed for point mutations in the p53 tumor suppressor gene. A single, identical point mutation consisting of a G:C to T:A transversion in codon 245 was identified in bronchial epithelium from 7 of 10 sites in both lungs. Epithelium at sites containing the p53 mutation was morphologically abnormal, exhibiting squamous metaplasia and mild to moderate atypia. No invasive tumor was found in the tracheobronchial tree or any other location. Cells from peripheral blood, kidney, liver, and lymph node exhibited no abnormality in the p53 gene. The widespread presence of a single somatic p53 point mutation in the bronchi of a smoker suggests that a single progenitor bronchial epithelial clone may expand to populate broad areas of the bronchial mucosa-a novel mechanism for field carcinogenesis in the respiratory epithelium that may be of importance in assessing individuals for risk of a second primary tumor as well as in devising effective strategies for chemoprevention of lung cancer.  相似文献   
20.
The surgical procedures used, the complications encountered and the results obtained in 549 patients with urinary stress incontinence with or without prolapse and 50 patients with prolapse without urinary stress incontinence are presented. Incontinence was cured in 347 patients, improved in 126, unchanged in 66 and worsened in ten. Seven patients operated on for uterine prolapse developed urinary incontinence after surgery. The overall recurrence of SUI was 12.75%. The introduction of suprapubic bladder drainage has practically eliminated postoperative urinary tract infections and reduced the length of hospitalization from 9.1 to 7.2 days. My experience in 214 patients with suprabpubic drainage demonstratedthe superiority of the Ansari method over the cystocath. The addition of Cantor's bladder neck plication improved the results (cured plus improved) from 80% to 100% in the Marshall-Marchetti-Krantz operation and from 81% to 86% when the Marshall-Marchetti-Krantz operation was associated with an abdominal hysterectomy.  相似文献   
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