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991.
992.
MS Cairo J Agosti R Ellis JJ Laver B Puppala R deLemos L Givner M Nesin JG Wheeler T Seth C van de Ven A Fanaroff 《Canadian Metallurgical Quarterly》1999,134(1):64-70
Perosomus elumbis, an infrequently encountered congenital anomaly of unknown etiology, was studied in a female Holstein calf. This error of morphogenesis represents a set of multiorgan malformations that produce a deformity of the caudal one third of the fetus. In this case, the spinal and pelvic malformations were radiographed and then dissected. Intra-abdominal abnormalities of the soft tissues are also described. The normal sequential embryologic development of the vertebrate skeleton, anterior-posterior fetal positioning, and neural tube migration are discussed. An extensive literature of this birth defect in cattle (and sheep) is reveiwed. The reports from a period covering 165 years are compared with the pathologic features in this case. Chromosomal aberrations within the homeobox gene family are postulated to be contributory factors in the development of this type of dysorganogenesis. 相似文献
993.
994.
S Kumaki HD Ochs KK Kuropatwinski T Konno MS Timour D Cosman H Baumann 《Canadian Metallurgical Quarterly》1999,115(2):356-361
Mutations of the common gamma (gammac) chain result in X-linked SCID (X-SCID), which is characterized by the reduction in number or absence of peripheral blood T cells and natural killer (NK) cells, with retention of normal numbers of B cells. In the present study we describe a novel mutant gammac chain of an X-SCID patient with a typical X-SCID phenotype. This mutant receptor subunit is able to associate with Jak3 to transduce a weak signal. The Jak3-specific action is demonstrated by the induction of gene expression through the haematopoietin receptor response element (HRRE) by IL-2 and IL-4 in the experimental model of transiently transfected hepatoma cells over-expressing Jak3. This result suggests that a threshold in the gammac-Jak3 interaction determines the X-SCID phenotype. 相似文献
995.
TW Picton C Alain DL Woods MS John M Scherg P Valdes-Sosa J Bosch-Bayard NJ Trujillo 《Canadian Metallurgical Quarterly》1999,4(2):64-79
Evoked potentials to brief 1,000-Hz tones presented to either the left or the right ear were recorded from 30 electrodes arrayed over the head. These recordings were submitted to two different forms of source analysis: brain electric source analysis (BESA) and variable-resolution electromagnetic tomography (VARETA). Both analyses showed that the dominant intracerebral sources for the late auditory-evoked potentials (50-300 ms) were in the supratemporal plane and lateral temporal lobe contralateral to the ear of stimulation. The analyses also suggested the possibility of additional sources in the frontal lobes. 相似文献
996.
J May GH White R Waugh MS Stephen X Chaufour W Yu JP Harris 《Canadian Metallurgical Quarterly》1999,29(1):32-7; discussion 38-9
PURPOSE: The aim of this study was to document the incidence rate of adverse events after endoluminal repair of abdominal aortic aneurysms (AAAs) during two successive periods of time. METHODS: One hundred ninety patients (175 men, 15 women; mean age, 72 years) underwent endoluminal repair of AAAs in a 5(1/2)-year period. Adverse events were documented prospectively for all the patients throughout this interval. An adverse event was defined as any of the following events: a death within 30 days, a conversion to open repair, the need for further intervention (either open or endovascular), the need for hemodialysis, a failure to cure the AAA, and wound complications. The patients were divided into two groups those who underwent operation in the initial 3-year period (group I; n = 75) and those who underwent operation in the subsequent 2(1/2)-year period (group II; n = 115). The results were analyzed for total adverse events for both periods of time and for difference in incidence rates within categories of adverse events between the two groups. RESULTS: Eight patients (4.2%) died in the perioperative period. The endoluminal repair failed in 17 patients (8.9%), which necessitated a primary conversion to open repair at the original operation. In 88 patients, 110 adverse events occurred. There was no significant difference in the incidence rates of adverse events in patients in group I (37/75) and group II (51/115). Apart from primary conversion (P =.007), there was no significant difference in the incidence rates of adverse events between group I and group II within the following categories: perioperative (within 30 days) deaths, primary conversion, secondary conversion, supplementary endoluminal repair, intervention for lower limb ischemia, hemodialysis necessitated, failure to cure the AAA as a result of persistent endoleak, and wound complications. CONCLUSION: Despite improvements in technology and increasing experience, adverse events continue to occur in a relatively high proportion of patients (45%) who undergo endoluminal repair of AAA. Reporting the incidence rates of adverse events provides a more accurate picture of the morbidity rates of the endoluminal method rather than simply listing the procedures as successes or failures. The similarity in the incidence rates of adverse events in patients in group I and group II suggests that there are inherent risks in the endoluminal method rather than iatrogenic complications that occur during the learning curve with a new technique. 相似文献
997.
MS Hu JD Schwartzman GR Yeaman J Collins R Seguin IA Khan LH Kasper 《Canadian Metallurgical Quarterly》1999,67(2):928-935
Ocular toxoplasmosis is a potentially blinding intraocular inflammation. The intent of this study was to investigate the role of Fas-FasL interaction in a murine model of acquired ocular toxoplasmosis induced by intracameral inoculation of Toxoplasma gondii. Intraocular inflammation, Fas and FasL expression on lymphocytes and on ocular tissues, the occurrence of apoptosis, and the frequency of CD8(+) and CD4(+) T cells in the infected eyes were analyzed in C57BL/6 (B6) mice. Susceptibility to parasite-induced intraocular inflammation was observed in Fas-deficient (B6-lpr) and FasL-deficient (B6-gld) mice. Inoculation of 5,000 T. gondii tachyzoites induced significant intraocular inflammation associated with increase of Fas and FasL expression in the inoculated eyes of wild-type B6 mice. Flow cytometry demonstrated a significant increase of Fas and FasL expression on the splenocytes from naive mice incubated in vitro with the parasite and on the splenocytes harvested from the infected mice at day 8 after parasite inoculation. Apoptosis of inflammatory cells and cells in ocular tissues was seen, and a greater frequency of CD8(+) than CD4(+) T cells was observed in the infected eyes. The intensity of intraocular inflammation was greater in B6-lpr and B6-gld mice than in wild-type B6 mice (P < 0.05). The results suggest that Fas-FasL interaction associated with apoptosis is involved in the pathogenesis of acquired ocular toxoplasmosis in mice. 相似文献
998.
AS Kamat N Ghadge MS Ramamurthy MD Alur 《Journal of the science of food and agriculture》2005,85(13):2213-2219
Minimally processed non‐irradiated carrots (sliced) exhibited diverse microflora at initial level. During storage, bacterial number increased with the presence of pathogenic bacteria accompanied by a loss of total solids. On the other hand γ‐irradiation at an optimal dose of 2 kGy offered a pathogen‐free, hygienic product with insignificant losses in nutrients such as in sucrose, total carotenes and ascorbic acid content in comparison to controls and 2‐ to 4‐fold increased in shelf‐life at refrigeration temperature. The D10 values of pathogens like Escherichia coli and Yersinia enterocolitica in carrot paste were in a lower range (0.12–0.26 kGy) compared with that of Listeria monocytogenes (0.3–0.5 kGy). The validity of the processing treatment (2 kGy) was challenged by artificially inoculating Listeria monocytogenes in the product. Thus, minimally processed carrots (sliced) are amenable to radiation treatment for extended storage stability and microbial safety. Copyright © 2005 Society of Chemical Industry 相似文献
999.
Numerous studies have demonstrated that exposure to misinformation about a witnessed event can lead to false memories in both children and adults. The present study extends this finding by identifying forced confabulation as another potent suggestive influence. Participants from 3 age groups (1st grade, 3rd/4th grade, and college age) viewed a clip from a movie and were "forced" to answer questions about events that clearly never happened in the video they had seen. Despite evidence that participants would not have answered these questions had they not been coerced into doing so, 1 week later participants in all age groups came to have false memories for the details they had knowingly fabricated earlier. The results also showed that children were more prone to this memory error than were adults. 相似文献
1000.
LK Romanova MS Pokrovskaia TB Mladkovskaia GV Kulikova EV Volkova LA Safronova ES Zhorova IK Beliaev GI Gerasiuto IS Sivakoba 《Canadian Metallurgical Quarterly》1998,60(5):32-36
The possibility of transplacental passage of Cr-90 and Cs-137 as well as their traces appearance in descendants muscles and bones beginning from the 2nd pregnancy trimester (and this was sometimes associated with teratogenic effects) was demonstrated on the abortion material (human embryos and fetuses) from the controlled zones of the Bryansk region. Statistically significant inhibition of the bronchial branching (according to the morphometry of the lung histological section) this indicating the disturbance of the lung prenatal morphogenesis during the "pseudoglandular" developmental stage was observed in the 1st trimester of the pregnancy in the descendants of the irradiated mothers. Lung hypoplasia was observed in some cases in the 2nd and 3rd trimesters of the pregnancy. Activation of lymphoid cells in the fetal lungs and the tendency to the enhancement in them of the ectopic erythroid hemopoiesis was revealed. These processes are considered as a reflection of the compensatory adaptive cellular reaction in the descendants respiratory organs in response to the tissue hypoxia and antigenic stimuli from the organism of the pregnant woman irradiated after the Chernobyl accident. 相似文献