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951.
A García Enguídanos E Crespo Azanza J Díaz Recaséns F Lobo Samper JA Jorge Herrero R Sáinz de la Cuesta Abbad 《Canadian Metallurgical Quarterly》1998,198(8):502-505
OBJECTIVE: To determine the usefulness of diagnostic tests performed before a second look laparotomy in patients with epithelial ovarian cancer. STUDY DESIGN: Thirty-three patients with epithelial ovarian cancer attended at Fundación Jiménez Díaz from 1984 to 1995 were studied. All patients initially underwent cyto-reducing surgery, followed by at least six platinum-based chemotherapy cycles. Prior to second look laparotomy all patients were evaluated by computerized tomography (CT) of the pelvis and abdomen, CA-125, pelvic-abdominal echography and gynecologic examination. To evaluate sensitivity, specificity, positive predictive value and negative predictive value for each test contingency tables were used. RESULTS: Eleven out of the 33 second look patients (33%) had histologic or cytologic evidence of disease. Six out of the eleven positive second look had a positive CT prior to second look (sensitivity of 55%). CT showed lack of disease in 21 out of the 22 negative second look cases (specificity 95%). Positive and negative predictive values of the test were 86% and 81%, respectively. Nine cases out of the 28 who had a CA-125 obtained had a positive second look. Four out of these nine patients had an increased CA-125 value (sensitivity 44%, specificity 95%, positive predictive value 80% and negative predictive value 78%). Sensitivity, specificity, positive predictive value and negative predictive value of physical examination and echography were 36%, 100%, 100%, 76% and 27%, 95%, 75%, 72%, respectively. On the other hand, sensitivity, specificity, positive predictive value and negative predictive value of all tests taken together were 64%, 91%, 78% and 83%, with a rate of false-negative results of 17% and a rate of false-positive results of 22%. CONCLUSION: Pelvic-abdominal computerized tomography, CA-125, pelvic-abdominal echography and gynecologic examination can be an alternative to second look laparotomy for the diagnosis of persistence or recurrence of the disease in patients with epithelial ovarian cancer. 相似文献
952.
A questionnaire was sent to all Human Fertilization and Embryology Authority-registered reproductive medicine centres throughout the UK to survey their policy for the diagnosis and management of antisperm antibodies. Forty-eight responses were received from the 74 units that use husbands' spermatozoa for treatments (65%). Most centres use at least one test to detect antibodies, although a minority perform no tests on the basis that their clinical practice would be unaltered if antibodies were present. Positive tests are classed as clinically significant at levels varying from > or = 10% to > or = 50% for direct sperm binding tests (mixed antiglobulin reaction, immunobead test), and ranging from any positive reaction to > or = 1:32 for the microtitre tests (gelatin and tray agglutination tests, microimmobilization test). Strategies for managing affected patients include no intervention, artificial insemination and intrauterine insemination (IUI) using spermatozoa prepared by various techniques, in-vitro fertilization (IVF) with or without increased insemination concentration, and intracytoplasmic sperm injection. Criteria for the latter are diverse, some centres managing all antibody-positive patients this way, while others resort to it only in severe cases or after other treatments have failed. Half of the respondents occasionally or regularly employ steroids, either alone or in conjunction with IUI or IVF. Overall, it appears that much confusion exists as to how best to manage couples presenting with antibody-related infertility. 相似文献
953.
954.
JA Marin-Neto MV Sim?es EM Ayres-Neto JL Attab-Santos L Gallo DS Amorim BC Maciel 《Canadian Metallurgical Quarterly》1995,113(2):826-834
Pathogenesis of chronic Chagas' heart disease may include various disturbances in the coronary circulation, that could be responsible for the myocardial lesions seen in human hearts and in experimental models of the disease. In this paper we critically reviewed the anatomical and functional abnormalities described in chronic chagasic patients, pertaining to the so-called vascular pathogenetic theory of Chagas' disease. The epicardial coronary arteries are usually free of significant obstructive disease in nonselected groups of chagasic patients examined at autopsy or by coronary angiography. However, chagasic patients who were studied after an episode of acute myocardial infarction, show the same patterns of atherosclerotic coronary artery disease seen in the general nonchagasic population. Studies of chagasic patients with angiographically normal coronary arteries, by several scintigraphy methods, revealed myocardial perfusion abnormalities which may be caused by the microcirculatory derangements described in animals experimentally infected with the T. cruzi. Since hypoperfusion has been detected in regions with normal or mildly impaired wall motion, it is likely that the microvascular disturbances precede and may be causative mechanism for the subsequent myocardial damage. We speculate that hibernating ventricular areas may occur in chagasic patients, on the basis of the evidence gathered from these studies. Recent investigations of chronic patients with Chagas' disease and chest pain showed attenuation of the vasomotor responses to physiological and pharmacological stimuli, in the epicardial coronary arteries. 相似文献
955.
Previous investigations have established the reliability of high-frequency thresholds performed in a sound suite using headphones. In addition, test-retest reliability of high-frequency thresholds in adults with normal hearing in a hospital room versus a sound-treated booth has also been established. The current study evaluated the test-retest reliability of thresholds in the 8000- to 18000-Hz range in 15 hearing-impaired adults (26 ears) with varying degrees of sensorineural hearing loss. A high-frequency audiometer and supra-aural earphones were used to measure thresholds in a typical hospital room. Results revealed no significant difference between repeated threshold measures. This study represents the third phase of an ongoing project to develop reliable bedside monitoring of patients undergoing ototoxic medical treatment. 相似文献
956.
957.
Limits on the exposure to high-peak-power, short-duration microwave pulses have only recently been adopted. Additional data, however, are needed to understand the effects that may be produced by exposure to high-peak-power pulsed microwaves. Four male rhesus monkeys (Macaca mulatta) were trained on an operant task for food pellet reward to investigate the behavioral effects of very high-peak-power 5.62 GHz microwaves. The operant task required monkeys to pull one plastic lever on a variable interval schedule (VI-25 s) and then respond to color signals and pull a second lever to obtain food. The monkeys were conditioned to perform a color discrimination task using one of three colors displayed by a fiber-optic cable. A red signal was the discriminative stimulus for responding on the first lever. A response on the second lever when a green signal was presented (1 s duration) delivered a food pellet. If a response on the second lever was made in the presence of a white signal, a 30-s timeout occurred. While performing the behavioral task, the monkeys were exposed to microwave pulses produced by either a military radar (FPS-26A) operating at 5.62 GHz or the same radar coupled to a Stanford linear energy doubler (SLED) pulse-forming device (ITT-2972) that enhanced peak power by a factor of nine by adding a high power pulse to the radar pulse. The effects of both types of pulses were compared to sham exposure. Peak field power densities tested were 518, 1270, and 2520 W/cm2 for SLED pulses and 56, 128, and 277 W/cm2 for the radar pulses. The microwave pulses (radar or SLED) were delivered at 100 pps (2.8 microseconds radar pulse duration; approximately 50 ns SLED pulse duration) for 20 min and produced averaged whole-body SARs of 2, 4, or 6 W/kg. Compared to sham exposures, significant alterations of lever responding, reaction time, and earned food pellets occurred during microwave exposure at 4 and 6 W/kg but not at 2 W/kg. There were no differences between radar or SLED pulses in producing behavioral effects. 相似文献
958.
The life expectancy of individuals with haemophilia was close to that of the general population in the early 1980s. Since then, life expectancy has decreased, due to transfusion-transmitted virus infections. Deaths in individuals with haemophilia were investigated by analysing 2450 records from the Canadian Hemophilia Registry, for the years 1980-1995. Deaths were tabulated by age, year and cause, and compared with that of the Canadian male population by calculating standardized mortality ratios (SMRs). The median life expectancy at 1 year of age was calculated for various subpopulations and the impact of various population characteristics was assessed by survival regression modelling. There were 359 deaths and the annual number of deaths increased significantly after 1986. Risk factors were seropositivity to human immunodeficiency virus (relative risk 16.7, 95% CI 11.1-25.1), severe haemophilia (1.9, 1.3-2.7) and moderate haemophilia (1.8, 1.2-2.6). In HIV antibody negative individuals, the overall death rate was not increased (SMR 0.9, 95% CI 0.7-1.1) and only haemorrhage was significantly increased. In HIV antibody positive individuals, causes of death which were significantly increased were acquired immunodeficiency syndrome, liver failure, haemorrhage, lymphoma, liver cancer, nonspecific infections, and trauma or violence. Deaths due to the acquired immunodeficiency syndrome accounted for only 66% of the excess deaths in individuals who were HIV antibody positive. Life expectancy has markedly decreased since the onset of the HIV epidemic. The impact of HIV is underestimated by considering only deaths due to the acquired immunodeficiency syndrome; other HIV-linked causes need also to be considered. 相似文献
959.
Mde L Chauffaille RM Valério CM Diniz MM Sim?es S Enokihara N Michalany KV Ferreira JA Martinez KM Hassun AN Atallah J Kerbauy 《Canadian Metallurgical Quarterly》1998,116(1):1625-1628
The authors present a rare case of Langerhans cell histiocytosis in a 31 year old female patient with vulvar, peri-anal and oral lesions, diabetes insipidus, pulmonary skin and bone infiltrations. Skin biopsy immunohistochemistry presented positive S100 protein and vimentin, but the diagnosis was done with the demonstration of Birbeck granules with electronic microscopy. The treatment was based on systematical chemotherapy although vulvar lesion has a bad response to chemotherapy. 相似文献
960.
The polychlorobiphenyl-degrading bacterium Rhodococcus globerulus P6 contains three bphC genes encoding 2,3-dihydroxybiphenyl 1,2-dioxygenases. One of them, bphC1, is clustered with the bphB gene which encodes 2,3-dihydroxy-4-phenylhexa-4,6-diene dehydrogenase and constitutes part of the bph operon specifying the degradation of biphenyl. The nucleotide sequence of bphB and the three bphC genes has been determined. The protein products of the bphBC1 gene cluster were found to exhibit significant homology with the corresponding proteins of analogous degradative pathways in Gram-negative bacteria; the highest homology was in those of the toluene degradation pathway of Pseudomonas putida strain F1. No homology was found between bphC2 and bphC3 and any other sequence in the database. At least two of the three meta cleavage enzymes are inducible by biphenyl. 2,3-Dihydroxybiphenyl 1,2-dioxygenase II, encoded by the bphC2 gene, was purified to apparent homogeneity from a recombinant Escherichia coli strain. The enzyme differed from other extradiol dioxygenases in having a subunit molecular mass of 21 kDa and a hexameric structure. The enzyme contains one tightly bound iron per subunit. These characteristics demonstrate that the 2,3-dihydroxybiphenyl 1,2-dioxygenases encoded by bphC2 and bphC3 belong to a new class of extradiol dioxygenases. 相似文献