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991.
TR Pollard WH Schwesinger EY Sako KR Sirinek 《Canadian Metallurgical Quarterly》1997,132(7):714-7; discussion 717-8
OBJECTIVE: To assess the outcomes of abdominal operations in patients with lung transplants and identify adverse risk factors. DESIGN: Matched cohort study. SETTING: University referral center. PARTICIPANTS: Twelve lung transplant recipients who required abdominal operations (hereafter referred to as case patients) and 12 age-, sex-, and pulmonary diagnosis-matched lung transplant recipients who had not undergone an abdominal procedure (hereafter referred to as control patients). INTERVENTIONS: Elective abdominal operations including laparoscopic cholecystectomies (n = 5), laparoscopic repair of a colovaginal fistula (n = 1), and open colectomy for a benign colovesical fistula (n = 1) and urgent operations including bowel resections (n = 3), subtotal pancreatectomy (n = 1), and hepatorrhaphy for an iatrogenic liver injury (n = 1). MAIN OUTCOME MEASURES: Morbidity and mortality. RESULTS: Abdominal operations were performed in 12 (11%) of the patients undergoing lung transplantation at the university referral center since 1987, with an associated mortality rate of 25%. Morbidity and mortality rates of electively performed procedures were 28% and 14%, respectively. An urgent indication for abdominal procedure was associated with 100% morbidity and 40% mortality. Compared with a matched group of 12 control patients, the long-term survival of the case patients was reduced (18% vs 64% at 4 years). Case patients undergoing an abdominal procedure in the posttransplantation period tended to have a higher prevalence of previous rejection (67% vs 25%), a higher perioperative steroid dosage (53 mg/d vs 36 mg/d), and a significantly lower posttransplantational forced expiratory volume in 1 second (FEV1, 1.23 L vs 1.91 L; P < .05). CONCLUSIONS: Elective abdominal operations are relatively safe in properly prepared lung transplant recipients. However, laparotomy for urgent surgical conditions is associated with increased morbidity and mortality rates caused in part by the magnitude of the abdominal operation and influenced by the status of the lung transplant as manifested by previous rejection episodes, perioperative steroid dosages, and FEV1 values. 相似文献
992.
993.
FM Campbell AM Clohessy MJ Gordon KR Page AK Dutta-Roy 《Canadian Metallurgical Quarterly》1997,38(12):2558-2568
In order to understand the mechanisms by which fatty acids are taken up by the placenta, the uptake of oleic, linoleic, arachidonic, and docosahexaenoic acids by cultured human placental choriocarcinoma (BeWo) cells was examined. Fatty acid uptake by BeWo cells was temperature-dependent and exhibited saturable kinetics. Oleic acid was taken up least and docosahexaenoic acid most by these cells. Moreover, competitive studies of fatty acid uptake by BeWo cells also indicated preferential uptake compared with oleic acid in the order of docosahexaenoic acid, arachidonic acid, and linoleic acid. Western blot analysis demonstrated that BeWo cells express a protein immunoreactive with antibodies to the human placental plasma membrane fatty acid-binding protein (p-FABPpm). Furthermore, pre-treatment of BeWo cells with these antibodies inhibited most of the uptake of docosahexaenoic (64%) and arachidonic acids (68%) whereas oleic acid uptake was inhibited only 32% compared with the controls treated with preimmune serum. These results clearly demonstrate that the pFABPpm may be involved in the preferential uptake of essential fatty acids (EFA) and their long chain polyunsaturated fatty acids (LCPUFA) by these cells. Studies on the distribution of radiolabeled fatty acids in the cellular lipids of BeWo cells showed that docosahexaenoic acid was incorporated mainly in the triacylglycerol fraction, followed by the phospholipid fraction, whereas for arachidonic acid the reverse was true. The preferential incorporation of docosahexaenoic acid into triacylglycerol suggests that triacylglycerol may play an important role in the placental transport of docosahexaenoic acid to the fetal circulation. Together these results demonstrate the preferential uptake of EFA/LCPUFA by BeWo cells that is most probably mediated via the pFABPpm. We thus propose that the p-FABPpm may be involved in the sequestration of maternal plasma LCPUFA by the placenta. 相似文献
994.
CA Conover LC Hartmann S Bradley P Stalboerger GG Klee KR Kalli RB Jenkins 《Canadian Metallurgical Quarterly》1998,238(2):439-449
Current hypotheses for explaining which sex cares for offspring assume a relationship between the mode of fertilization and the sex showing parental care. In general, it is hypothesized that maternal care should be concentrated in taxa with internal fertilization, and paternal care should be concentrated in taxa with external fertilization. Studies have supported this relationship; however, new comparative techniques and new data on parental care and the frequency of internal fertilization in anurans suggest that the relationship should be re-evaluated. I examined the relationship between mode of fertilization and sex providing parental care in 334 taxa of anurans using concentrated changes tests and in 396 taxa of anurans using a method developed by Ridley (1983. The Explanation of Organic Diversity. The Comparative Method and Adaptations of Mating. Oxford: Clarendon). The results of the concentrated changes tests showed that both female and male parental care are randomly distributed among taxa with respect to mode of fertilization. However, using Ridley's method, I found significant relationships between mode of fertilization and sex providing parental care. The observed and expected numbers of transitions from external fertilization and no parental care to external fertilization and male parental care or to internal fertilization and female parental care are not qualitatively different. Therefore, the results of my analyses suggest that current hypotheses for explaining the occurrence of maternal versus paternal care in anurans should be reconsidered. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
995.
We performed 34 antenatal MRI, in utero in 29 foetuses with cerebral malformations depicted by US. For five patients, a second antenatal MRI was performed because of a technical failure or of diagnosis doubt. We considered that MRI is a valuable imaging method. We have observed 2 false negatives (myelomeningocele, gyration abnormality) on MR study (n = 34). MRI is more contributive that US for the etiological diagnosis of ventricular enlargement: 83% versus 46%. MRI depicted corpus callosum agenesis misdiagnosed in 5 patients by US. MR results modified the therapeutic procedure in 37% of our patients. We think that the optimal term to perform MRI study is after 28 weeks gestational age because of the size of the fetus and for the timing of cerebral development. Ventricular dilatation (criteria: occipital horn size more that one centimeter at 25 weeks of term) is the main indication of MR study. 相似文献
996.
The bcr-abl chimeric oncoprotein exhibits deregulated protein tyrosine kinase activity and is implicated in the pathogenesis of Philadelphia chromosome (Ph)-positive human leukemias, such as chronic myelogenous leukemia (CML). Recently we have shown that the levels of the protein tyrosine phosphatase PTP1B are enhanced in p210 bcr-abl-expressing cell lines. Furthermore, PTP1B recognizes p210 bcr-abl as a substrate, disrupts the formation of a p210 bcr-abl/Grb2 complex, and inhibits signaling events initiated by this oncoprotein PTK. In this report, we have examined whether PTP1B effects transformation induced by p210 bcr-abl. We demonstrate that expression of either wild-type PTP1B or the substrate-trapping mutant form of the enzyme (PTP1B-D181A) in p210 bcr-abl-transformed Rat-1 fibroblasts diminished the ability of these cells to form colonies in soft agar, to grow in reduced serum, and to form tumors in nude mice. In contrast, TCPTP, the closest relative of PTP1B, did not effect p210 bcr-abl-induced transformation. Furthermore, neither PTP1B nor TCPTP inhibited transformation induced by v-Abl. In addition, overexpression of PTP1B or treatment with CGP57148, a small molecule inhibitor of p210 bcr-abl, induced erythroid differentiation of K562 cells, a CML cell line derived from a patient in blast crisis. These data suggest that PTP1B is a selective, endogenous inhibitor of p210 bcr-abl and is likely to be important in the pathogenesis of CML. 相似文献
997.
DP Schammel KR Mittal K Kaplan L Deligdisch FA Tavassoli 《Canadian Metallurgical Quarterly》1998,17(4):327-335
Endometrial adenocarcinoma associated with pregnancy is a rare lesion; only 14 acceptable examples have been reported in the literature. This study describes five additional examples with a critical review of the previously published cases. Four of the five women were nulliparous and three had sought medical intervention for infertility. The tumors were all well-differentiated endometrioid adenocarcinomas; three had a focal to extensive papillary pattern and three had focal to extensive squamous differentiation. Four were diagnosed at the time of dilatation and curettage and one at the time of cesarean section for a 28-week, live infant. Follow-up was available for four of the five women. Two women underwent hysterectomy with bilateral oophorectomy and were alive and well 12 and 48 months after diagnosis. The woman who had the live birth and the remaining woman were treated by repeat curettage with or without progesterone therapy, and each woman has had two subsequent full-term pregnancies with live births. These women are alive and well 57 and 58 months after diagnosis. Women with focal, well-differentiated carcinomas can successfully maintain their fertility if followed by repeat curettage with or without progesterone therapy. 相似文献
998.
JR Sawyer JL Lukacs N Munshi KR Desikan S Singhal J Mehta D Siegel J Shaughnessy B Barlogie 《Canadian Metallurgical Quarterly》1998,92(11):4269-4278
Multicolor spectral karyotyping (SKY) was performed on bone marrow samples from 50 patients with multiple myeloma (MM) in anticipation of discovering new previously unidentified translocations. All samples showed complex karyotypes with chromosome aberrations which, in most cases, were not fully characterized by G-banding. Patients of special interest were those who showed add(14)(q32), add(8)(q24) and those whose G-banding karyotypes showed poor chromosome morphology. Three new recurring chromosome translocations not previously reported in MM were identified. Two of the translocations involve recurring aberrations at band 14q32.3, the site of the IgH locus, with different exchange partners. The most frequently recurring rearrangement was a subtle translocation at 14q32.3 designated as a t(14;16)(q32;q22 approximately 23), which was identified in six patients. A second and larger translocation at 14q32, identified in two patients, was designated as a t(9;14)(p13;q32), previously associated with Waldenstrom's macroglobulinemia and lymphoplasmacytoid lymphoma. A third translocation, identified in two patients, involved a whole-arm t(6;8)(p10;q10) translocation. The SKY technique was able to refine the designations of over 156 aberrations not fully characterized by G-banding in this study and resolved additional chromosome aberrations in every patient studied except two. The t(14;16)(q32;q22 approximately 23) identified by SKY in this study suggests this may be a frequent translocation in MM associated with complex karyotypes and disease progression. Therefore, the SKY technique provides a useful adjunct to routine G-banding and fluorescence in situ hybridization studies in the cytogenetic analysis of MM. 相似文献
999.
LM Clark WM McDonald KA Welsh-Bohmer IC Siegler DV Dawson LA Tupler KR Krishnan 《Canadian Metallurgical Quarterly》1998,44(7):592-599
Even today psychotic depression is connected to a lot of unanswered questions. A self-questionnaire (BFD) was developed in order to evaluate cognitions corresponding to mood congruent depressive delusions. They were assumed to indicate psychotic depression and to be related to severity of the depressive syndrome. 42 depressed inpatients were examined by the BFD, the Hamilton Depression Scale (HAMD) and the Beck Depression Inventory (BDI). BFD scores were found increased in psychotic depression (p = 0.009) and correlated to BDI scores (p = 0.002). 19 re-examined patients showed a significant improvement in HAMD and BDI scores but not concerning the delusion indicating cognitions (BFD), which were significantly correlated to suicidality items of BDI and HAMD (p = 0.005). The results prove the delusion indicating nature of cognitions measured by the BFD and their correlation to severe depression. Differences in treatment response are indicated and persisting or increasing BFD scores seem to be accompanied by more severe suicidal tendency. 相似文献
1000.
Development of ocular dominance columns is dependent on patterned retinal activity, and yet patterned activity alone cannot explain all aspects of cortical column development. Features intrinsic to the cortex have been proposed to interact with activity to guide the patterning of cortical columns (), and the NMDA receptor, because of its role in experience-dependent plasticity, is an obvious candidate. Using immunohistochemical techniques, we found a transiently patchy distribution of the NMDA receptor 1 (NMDAR1) subunit in kitten visual cortex. Regularly spaced patches of NMDAR1-immunoreactive neurons were found at the top of the cortical plate in the developing visual cortex at 2 weeks of age. At 4-5 weeks of age, the radial extent of the NMDAR1 patches spanned the supragranular layers, and by 12 weeks of age, this nonuniform pattern of NMDAR1 immunostaining was no longer apparent. Monocular visual experience prevented the expression of the NMDAR1 patches, but just 4 d of subsequent binocular visual experience was sufficient to promote expression of the patches. Furthermore, the NMDAR1 patches tended to be associated with the borders of ocular dominance columns. These results suggest that the degree of plasticity associated with NMDA-mediated mechanisms is elevated in local regions across the tangential extent of the visual cortex and that the NMDAR1 patches may participate in sculpting the overall arrangement of visual cortical columns. 相似文献