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991.
The diagnostic possibilities of intrauterine ultrasonic assessment of the fetal abdomen by rapid B-scan are described on the basis of two cases (megalocystis/megaloureter syndrome and omphalocele with cloaca formation). Other examination methods of prenatal diagnosis to confirm the findings are also discussed, but their diagnostic significance is even more limited than that of sonography, individual cases excepted. Although early detection of neural tube anomalies is the most important application of ultrasound, pronounced monstrosities of the fetal abdominal region are also definitely recognisable via ultrasonic examination. 相似文献
992.
The behavioural mutant mouse Lurcher survives to adult life as the heterozygote (Lc/+) and shows a disorder of gait. The neurological lesion has been shown to involve degeneration of Purkinje cells and inferior olivary neurones (Caddy and Biscoe 1976). It follows that the climbing fibre input is reduced and we wished to know if the mossy fibre input was also affected. Heterozygote Lurcher mutants were compared with the wild type in all experiments. Mossy fibre glomeruli were identified in the cerebellum of the mutant mouse by electron microscopy. Horseradish peroxidase (HRP) was injected into the cerebellum and was found in the cells of Clarke's column in the spinal cord. Electrophysiological experiments showed that following stimulation of the sciatic nerve evoked responses could be recorded in the cerebellum. It is concluded that the mossy fibre input to the cerebellum is intact in the Lurcher mutant mouse. 相似文献
993.
MH Brown KW Davies CM Billon C Adair PJ McClure 《Canadian Metallurgical Quarterly》1998,61(11):1446-1453
Ensuring microbiological safety requires identification of realistic hazards and the means of controlling them. The risk assessment framework proposed by Codex Alimentarius allows the impact of raw materials and processes to be appreciated, and the output can be used for risk management and communication. Mathematical models allow numerical information to be processed by a computer and interpreted to give quantitative or comparative risk assessments. In this example, models have been put together according to the Codex. Alimentarius principles, providing a quantitative risk assessment (QRA) of salmonellosis from frozen poultry products. This model-based QRA takes into account three types of information: occurrence and distribution of the agent, sensitivity of populations to infection (e.g., normal or susceptible), and the effect of cooking (in the factory or home) on concentration of the agent and hence risks of infection after product consumption. It only demonstrates the impact of a single-process step (heating) and the effect of changes in population sensitivity, raw material quality, and cooking regime on the final risk. The effects of growth and recontamination are not considered. To aid risk communication, the models have been visualized by means of displays and slider controls on a computer screen because effective communication is essential to encourage manufacturers and their product designers to assess the effect of changes in processing or materials on risk. 相似文献
994.
FJ Rescorla PP Breitfeld KW West D Williams SA Engum JL Grosfeld 《Canadian Metallurgical Quarterly》1998,124(4):670-5; discussion 675-6
BACKGROUND: This case controlled study compares the efficacy, safety, and cost of laparoscopic splenectomy (LS) and open splenectomy (OS) for hematologic disorders in children. METHODS: The records of 82 consecutive children and adolescents undergoing splenectomy for hematologic disorders between August 1994 and September 1997 were reviewed retrospectively. RESULTS: Fifty patients underwent LS by a lateral approach and 32 underwent OS through a left subcostal incision. Mean age was 7.76 years for LS and 6.9 years for OS. Patient weights were similar: (LS, mean 30.5 kg; OS, mean 27.6 kg). Hematologic indications included hereditary spherocytosis in 43 children (LS 26, OS 17), sickle cell anemia with sequestration in 13 (LS 7, OS 6), immune thrombocytopenic purpura in 14 (LS 8, OS 6), and 12 with other disorders (LS 9, OS 3). Concomitant cholecystectomy was performed in 10 of 50 LS and 6 of 32 OS cases. Accessory spleens were identified in 8 of 32 (25%) OS and 9 of 50 (18%) LS cases (P = .578). No LS procedures required conversion to OS. The mean estimated blood loss was 54.4 mL for LS and 49.0 mL for OS (P = .233). LS required a longer operative time (115 vs 83 minutes, P = .002), less need for postoperative intravenous narcotic (51% vs 100%, P < .0001), lower total narcotic doses (0.239 vs 0.480 mg/kg morphine, P = .006), shorter length of hospital stay (1.4 +/- 0.97 vs 2.5 +/- 1.43 days, P = .0001), and lower average total hospital charges ($5713 vs $6564) than OS. There were no deaths or major complications in either group. CONCLUSIONS: Laparoscopic splenectomy is a safe and effective procedure in children with hematologic disorders resulting in longer operative times, less narcotic administration, shorter length of stay, and lower total hospital charge. 相似文献
995.
KW Olsen 《Canadian Metallurgical Quarterly》1980,622(2):259-267
The internal amino acid residues of proteins are almost always non-polar since the hydrophobic effect is very important in stabilizing the three-dimensional structure. This fact suggests several new criteria for judging the correctness of structures predicted from sequence data. The dinucleotide binding domain has been used as a test structure for these criteria. The percentage of ionic residues, mutation data, hydrophobicity, dipole moments, and internal preferences of the residues on the interiors of the known dinucleotide binding folds are consistent with expectations. On the other hand, the values of these parameters for predicted domains in glutamate dehydrogenase (Wootton, J.C. (1974) Nature 252, 542--546) and aldolase (Stellwagen, E. (1976) J. Mol. Biol. 106, 903--911) differ significantly from the expected values indicating that these predictions are not entirely correct. The internal residue criteria can then be used to test modifications of the predictions for a better correlation with the internal residue pattern of the domain. 相似文献
996.
997.
998.
The protective anti-beta abortus monoclonal antibody ISS/32 (Ab1) was used as an immunogen to induce anti-idiotypic antibodies (Ab2) in rabbits. The purpose was to produce and characterize anti-idiotypic antibodies that share conformational similarity with the corresponding bacterial epitope recognized by Ab1. The rabbit anti-IdAb so induced was isolated and affinity-purified. Its specificity for the paratope of Ab1 was determined by evaluating its ability to compete with B. abortus for binding to Ab1 in a competitive ELISA assay. The anti-idiotypic ISS/32 antibodies were able to compete with B. abortus for binding to Ab1 in a dose-dependent manner. Hence, the data indicated that the rabbit anti-Id ISS/32 antibodies reacted with or near the antigen-binding site of Ab1. 相似文献
999.
The hemodynamic response to nitroglycerin administration, to sublingual or oral administration of isosorbide dinitrate, or to a placebo was evaluated and compared in 37 patients with unstable angina pectoris under resting, pain-free conditions. Patients with congestive heart failure were not included in this study. Serial measurements of mean arterial blood pressure (MAP), pulmonary arterial end-diastolic pressure (PAEDP), cardiac index (CI), and heart rate (HR) were obtained for one hour following nitroglycerin administration and for four hours following sublingual or oral administration of isosorbide dinitrate. Echocardiographic end-diastolic volume (EDV) measurements were obtained for the groups receiving isosorbide dinitrate or placebo. There was a significant (P less than 0.05 or less than 0.1) reduction of the MAP (5 to 10 mm Hg) that persisted for more than four hours following both sublingual and oral administration of isosorbide dinitrate. The changes in the PAEDP, HR, and CI following sublingual or oral administration of isosorbide dinitrate were small and not significant. In the group receiving isosorbide dinitrate sublingually, the EDV was reduced by more than 30 ml below the placebo group (P less than 0.1) for up to four hours. The effects of nitroglycerin administration were similar in magnitude but of much shorter duration (three to four hours for sublingual and oral administration of isosorbide dinitrate vs 15 to 30 minutes for nitroglycerin). These data demonstrate that the duration of the hemodynamic effects of sublingually and orally administered isosorbide dinitrate in patients with unstable angina pectoris and normal resting hemodynamics is 8 to 12 times longer than that of nitroglycerin. 相似文献
1000.
A prospective study was carried out from June 1973 to August 1976 in 131 women fitted with a newly developed IUD (Progestasert). The IUD's were removed as planned after 12 months with the exception of 4 cases in which they were retained for up to 17 months. The evaluation of the trial was performed according to the Life Table Analysis and the usual statistical methods. 1496 application months were evaluated. One case each of intrauterine and extrauterine pregnancies were observed. One patient experienced spontaneous expulsion of the IUD. In 9 cases medical reasons led to the removal of Progestasert at an earlier date. Duration, intensity, and interval of menstruation as well as frequency of spotting and dysmenorrhea were recorded. A slight increase in duration and interval of menstruation was seen whereas bleeding intensity was reduced. Increased spotting, especially during the first month after insertion, and a significant reduction of dysmenorrheal complaints were noted after 2 months. In addition to 8 removals due to bleeding disturbances, 6 other patients experienced spotting throughout the entire treatment period. Laboratory tests such as ESR, WBC, hemoglobin, hematocrit and cytological smear determinations were carried out. No pathological alterations of these parameters were found. 相似文献