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991.
992.
G Hoheisel M Roth CH Chan DA Tsakiris B Fehr PW Ruff AP Perruchoud 《Canadian Metallurgical Quarterly》1997,64(2):152-158
The authors tested free-ranging New World monkeys (nocturnal owl monkeys [Aotus nancymai] and diurnal capuchin monkeys [Cebus apella]) to determine the extent to which they use olfactory cues to locate food hidden in containers at 2 of 6 feeding sites within a 1 1/2-ha forested enclosure. These 2 sites were selected randomly for each trial and then were baited with banana and banana peel residue. The 4 other sites were unbaited and unscented. In trials in which the food was not visible to the monkeys, Aotus monkeys located the baited sites at a level greater than expected by chance, whereas Cebus monkeys did not. Use of olfactory information by Aotus monkeys in foraging may be an adaptation for nocturnal foraging because olfactory cues are more salient than visual cues at low light levels. 相似文献
993.
JS Shinbane E Chu T DeMarco Y Sobol AP Fitzpatrick DM Lau C Klinski NB Schiller JC Griffin K Chatterjee 《Canadian Metallurgical Quarterly》1997,30(5):1295-1300
OBJECTIVES: This study evaluated how variations in atrioventricular (AV) delay affect hemodynamic function in patients with refractory heart failure being supported with intravenous inotropic and intravenous or oral inodilating agents. BACKGROUND: Although preliminary data have suggested that dual-chamber pacing with short AV delays may improve cardiac function in patients with heart failure, detailed Doppler and invasive hemodynamic assessment of patients with refractory New York Heart Association class IV heart failure has not been performed. METHODS: Nine patients with functional class IV clinical heart failure had Doppler assessment of transvalvular flow and right heart catheterization performed during pacing at AV delays of 200, 150, 100 and 50 to 75 ms. RESULTS: Systemic arterial, pulmonary artery, right atrial and pulmonary capillary wedge pressures, cardiac index, systemic and pulmonary vascular resistances, stroke volume index, left ventricular stroke work index (SWI) and arteriovenous oxygen content difference demonstrated no significant changes during dual-chamber pacing with AV delays of 200 to 50 to 75 ms. There were also no changes in the Doppler echocardiographic indexes of systolic or diastolic ventricular function. The study was designed with SWI as the outcome variable. Assuming a clinically significant change in the SWI of 5 g/min per m2, a type I error of 0.05 and the observed standard deviation from our study, the observed power of our study is 85% (type II error of 15%). CONCLUSIONS: Changes in AV delay between 200 and 50 ms during dual-chamber pacing do not significantly affect acute central hemodynamic data, including cardiac output and systolic or diastolic ventricular function in patients with severe refractory heart failure due to dilated cardiomyopathy. 相似文献
994.
AP Sch?fer MA Koch I Grosch-W?rner W Friedmann JW Dudenhausen 《Canadian Metallurgical Quarterly》1994,54(11):617-622
Within a prospective study of the course of HIV-infection in women, 80 HIV-infected women without AIDS were delivered of 80 children between 1985 and September 1992. The median of the age of gestation was 38 weeks. Until 1988 Caesarean section was chosen as mode of delivery (45 women). Later when the mode of delivery appeared to have no influence on the frequency of maternofetal HIV transmission, vaginal delivery was preferred (35 women). None of the infants was breastfed. Three infants --delivered vaginally--died within the first 6 months of life before their infection status could be determined. Seventy-seven children could be observed for 18 months or longer regularly every three months. 10 of the 77 children were found to be HIV- infected by serological, virological and clinical criteria. Taking into account the mode of delivery, of 32 children who were delivered vaginally or by emergency Caesarean section 8 were found to be HIV-infected. None of 26 children delivered by elective Caesarean section after an uneventful pregnancy is infected. In 19 women Caesarean section was performed within 2 hours after onset of labour or after episodes of preterm labour which required hospital admission for treatment. Two children of these women are infected. No differences of CD4+ cell counts and p24 antigenaemia could be determined between the mothers of the three groups. The risk of fetal HIV infection was increased by preterm labour (p < 0.01) and the mode of delivery (p < 0.01). A correlation between loss of CD4 cells in the mother and increased risk of infection for the child is seen in children born spontaneously or delivered by emergency Caesarean section (p < 0.001). No correlation was found between the length of labour at delivery, the time of the rupture of membranes before birth as well as of the parity and the risk of fetal infection in that group. These findings point to labour as an important factor which increases the risk of maternofetal transmission of HIV. The onset of labour is accompanied by dramatic immunological alterations as a sudden increase of chemotactics and inflammatory cytokines at the maternofetal interface. The accumulation and stimulation of maternal immune cells will--if these cells are carriers of HIV--result in production and release of infectious HIV. This virus may accumulate in the maternofetal interface or gain access to the amniotic cavity. Since amniotic fluid is swallowed by the fetus, the largest potential port of entry for HIV in the fetus are the fetal lungs and the gastrointestinal tract. For the prevention of maternofetal transmission of HIV delivery before onset of labour or alternatively the protection of the fetus during parturition by means of potent antiviral compounds can be considered. 相似文献
995.
996.
AP Gimenez-Roqueplo S Casanova E Bruckert F Bolgert G Turpin 《Canadian Metallurgical Quarterly》1994,23(27):1243-1246
POEMS syndrome is a rare systemic multi-organ disease usually reported in Japanese patients. The clinical course is slow with a 5-year survival of 60%. Death is caused by polyneuropathy and or anasarka. We observed four cases in our ward (all males, aged 39, 57, 54 and 54 years) who all presented at least four characteristic clinical signs. Gynecomasty together with impotency was seen in all patients. All had hypogonadism and borderline hyperprolactinaemia. Hyperoestrogenism was seen in two. In three patients, rare endocrinopathies were part of the POEMS syndrome. One patient had diabetes mellitus. The clinical course was variable and a function of the effectiveness of plasmocyte dyscrasia therapy. Little work has been done on endocrinopathies in POEMS syndrome. In most cases, gonadotrope function is impaired with gynecomasty and impotency in men, amenorrhoea in women. Generally the hypogonadism is hypogonadotropic. Hyperoestrogenism is frequent and prolactin levels are normal or high with an exaggerated response to thyroid releasing hormone stimulation. The aetiology of POEMS syndrome is unknown. Current research is based on an immunologic theory based on the discovery of high levels of interleukin 6 in POEMS patients with or without Castleman's disease. The cytokine would affect the different organs and lead to clinical expression. Corticosteroids are usually effective in most patients, particularly in reducing the oedema and controlling the polyneuropathy. 相似文献
997.
998.
SF Thijsen GJ Schuurhuis JW van Oostveen AP Theijsmeijer AW Niewint GJ Ossenkoppele 《Canadian Metallurgical Quarterly》1997,20(10):835-842
Although the mobilization and harvesting of Philadelphia chromosome-negative progenitors has been proven feasible by a number of groups, it is not clear which techniques should be used with regard to the monitoring of purging and evaluation of stem cell yield. Therefore, we isolated CD34-positive cells from leukapheresis samples of seven CML patients after induction therapy. These cells were analyzed using the colony-forming unit granulocyte-macrophage (CFU-GM) and long-term culture-initiating cell (LTCIC) assays. In addition, we analyzed frequency and clonogenicity of single stem cells using the LTCIC assay at limiting dilution. Individual colonies derived from these assays were subsequently analyzed for the presence of the bcr-abl gene with interphase fluorescence in situ hybridization (FISH) and for the presence of bcr-abl mRNA with RT-PCR. We compared these results with the cytogenetic analysis of the leukapheresis material. Molecular analysis of individual colonies correlated well with the results of cytogenetic analysis. However, in nine out of 18 samples, cytogenetic analysis exclusively demonstrated the presence of either Philadelphia chromosome-positive or -negative cells whereas with the molecular analysis of individual colonies tumor contamination or the presence of residual normal cells could be substantiated. We concluded that molecular analysis of individual colonies should be employed to further optimize induction protocols. With regard to stem cell mobilization we demonstrated that about 67 CFU-GM colonies and clusters were generated by one single LTCIC both for the CML samples and the samples obtained from patients with non-hematologic malignancy. This number is important since until now most centres use a number of four colonies and clusters generated by one LTCIC. Dividing the CFU-GM output in the LTCIC assay by four to determine LTCIC frequency could thus lead to an almost 20-fold overestimation of the LTCIC frequency. It is concluded that stem cell frequency analysis is an important tool with regard to the interpretation of mobilization protocols. 相似文献
999.
1000.
S Spiezia A Colao AP Assanti G Cerbone GM Picone B Merola G Lombardi 《Canadian Metallurgical Quarterly》1996,91(5):616-621
The aim of this study was twofold: first, to improve the predictive value of ultrasonography (US) in differentiating benign from malignant thyroid nodules and, second, to investigate whether color Doppler and power Doppler can distinguish different morpho-hemodynamic patterns of hypoechoic thyroid nodules according to their vascularity. Twenty-nine patients with hypoechoic thyroid nodule(s) were entered into this work in progress. Three typical power Doppler patterns were recorded and compared with color Doppler patterns and with cytologic and/or histologic findings. Power Doppler patterns were classified as follows: type A, a perilesional vascular halo; type B, a peri- and intralesional vascular halo, subdivided into: 1) with moderate intralesional vascularization, homogeneous structure and regular vessel caliber and 2) with rich intralesional vascularization, anarchical structure and winding vessel caliber and flow; type C, a perilesional vascular halo with a characteristic peripheral large afferent vessel characterized by winding caliber and flow. Of 29 patients, 21 had type A power Doppler (benign nodular goiter at cytology, in 4 of them with regressive phenomena); seven patients had type B power Doppler patterns-4 had a subtype 1 pattern (3 with nodular hyperplasias and 1 with a papillary adenoma), 3 had a subtype 2 (two had a follicular adenoma and one had a final diagnosis of angioinvasive follicular carcinoma). The patient with undifferentiated carcinoma had a type C power Doppler pattern. In conclusion, according to our early results, PD seems to be more sensitive and reliable than CD in the screening of thyroid nodules, and to yield better vascular information. 相似文献