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91.
We report the case of a 57-yr-old woman presenting with moderate weight loss, abdominal distension, and lymphedema of the legs and vulva. Computed tomography of the abdomen revealed massive thickening of the rectal wall, mesentery, and retroperitoneum. Primary amyloidosis was diagnosed by immunohistochemistry from the rectum and duodenum. To our knowledge, lymphedema due to primary amyloidosis has not yet been reported. The diagnosis should be presumed in the case of retroperitoneal thickening and lymphedema and can be established by immunohistochemistry. 相似文献
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C Bais B Santomasso O Coso L Arvanitakis EG Raaka JS Gutkind AS Asch E Cesarman MC Gershengorn EA Mesri MC Gerhengorn 《Canadian Metallurgical Quarterly》1998,391(6662):86-89
The Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8) is a gamma-2 herpesvirus that is implicated in the pathogenesis of Kaposi's sarcoma and of primary effusion B-cell lymphomas (PELs). KSHV infects malignant and progenitor cells of Kaposi's sarcoma and PEL, it encodes putative oncogenes and genes that may cause Kaposi's sarcoma pathogenesis by stimulating angiogenesis. The G-protein-coupled receptor encoded by an open reading frame (ORF 74) of KSHV is expressed in Kaposi's sarcoma lesions and in PEL and stimulates signalling pathways linked to cell proliferation in a constitutive (agonist-independent) way. Here we show that signalling by this KSHV G-protein-coupled receptor leads to cell transformation and tumorigenicity, and induces a switch to an angiogenic phenotype mediated by vascular endothelial growth factor, an angiogenesis and Kaposi's-spindle-cell growth factor. We find that this receptor can activate two protein kinases, JNK/SAPK and p38MAPK, by triggering signalling cascades like those induced by inflammatory cytokines that are angiogenesis activators and mitogens for Kaposi's sarcoma cells and B cells. We conclude that the KSHV G-protein-coupled receptor is a viral oncogene that can exploit cell signalling pathways to induce transformation and angiogenesis in KSHV-mediated oncogenesis. 相似文献
96.
AS Lages KC Silva AL Miranda CA Fraga EJ Barreiro 《Canadian Metallurgical Quarterly》1998,8(2):183-188
OBJECTIVE: To study the effect of adjuvant chemotherapy after curative hepatic resection in patients with hepatocellular carcinoma. DESIGN: A randomized controlled trial. SETTING: A tertiary referral center. PATIENTS: During a 54-month period, 142 patients with hepatocellular carcinoma underwent hepatic resection at 1 institution. Sixty-six patients who survived the operation and had no demonstrable evidence of residual disease on ultrasonographic examination and hepatic angiographic testing at 1 month after surgery agreed to participate in the study. The median follow-up time was 28.3 months. INTERVENTION: Thirty patients received a combination of intravenous epirubicin hydrochloride (8 doses of 40 mg/m2 each at 6-week intervals) and transarterial chemotherapy using an emulsion of iodized oil and cisplatin (3 courses with a maximum dose of 20 mL each at 2-month intervals). Thirty-six patients had no adjuvant treatment. MAIN OUTCOME MEASURES: Recurrence rate and disease-free survival. RESULTS: A total of 138 courses of intravenous epirubicin was given to the 30 patients. Sixty-one courses of transarterial chemotherapy were given to only 29 of the 30 patients assigned to the treatment group, because the hepatic artery in 1 patient was thrombosed. Six patients (20%) had chemotherapy-related complications with no mortality. Twenty-three of 30 patients in the treatment group and 17 of 36 patients in the control group had recurrences (P=.01). Patients who received adjuvant chemotherapy had a higher incidence of extrahepatic metastases (11 patients vs 5 patients; P=.03). The respective disease-free survival rates at 1, 2, and 3 years were 50%,36%, and 18% for the treatment group and 69%, 53%, and 48% for the control group (P=.04). CONCLUSION: In a group of patients who underwent curative resection of hepatocellular carcinoma, postoperative adjuvant chemotherapy using the present regimen was associated with more frequent extrahepatic recurrences and a worse outcome. 相似文献
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A hypothesis on autoregulatory mechanism of reproduction of bone matrix structural changes was proposed resulting from the theoretical study based on author's own data and data documented in literature. This mechanism seems to underly osteoporosis development. All etiological factors of osteoporosis reported were united into a common pathogenetic mechanism on the basis of this conception. 相似文献
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CT Wass JR Waggoner DG Cable HV Schaff DR Schroeder WL Lanier 《Canadian Metallurgical Quarterly》1998,115(6):1350-1357
BACKGROUND: Neurologic complications, primarily resulting from ischemic insults, represent the leading cause of morbidity and disability, and the second most common source of death, after cardiac operations. Previous studies have reported that increases (as occur during the rewarming phase of cardiopulmonary bypass [CPB]) or decreases in brain temperature of a mere 0.5 degrees to 2 degrees C can significantly worsen or improve, respectively, postischemic neurologic outcome. The purpose of the present study was to evaluate a novel approach of selectively cooling the brain during hypothermic CPB and subsequent rewarming. METHODS: Sixteen dogs were anesthetized with either intravenous pentobarbital or inhaled halothane (n = 8 per group). Normocapnia (alpha stat technique) and a blood pressure near 75 mm Hg were maintained. Temperatures were monitored by placing thermistors in the esophagus (i.e., core), parietal epidural space, and brain parenchyma at depths of 1 and 2 cm beneath the dura. During CPB, core temperature was actively cycled from 38 degrees C to 28 degrees C, and then returned to 38 degrees C. Forced air pericranial cooling (air temperature of approximately 13 degrees C) was initiated simultaneous with the onset of CPB, and maintained throughout the bypass period. Brain-to-core temperature gradients were calculated by subtracting the core temperature from regional brain temperatures. RESULTS: In halothane-anesthetized dogs, brain temperatures at all monitoring sites were significantly less than core during all phases of CPB, with one exception (2 cm during systemic cooling). Brain cooling was most prominent during and after systemic rewarming. For example, during systemic rewarming, average temperatures in the parietal epidural space, and 1 and 2 cm beneath the dura, were 3.3 degrees +/- 1.3 degrees C (mean +/- standard deviation), 3.2+/-1.4 degrees C, and 1.6 degrees +/-1.0 degrees C, cooler than the core, respectively. Similar trends, but of a greater magnitude, were noted in pentobarbital-anesthetized dogs. For example, during systemic rewarming, corresponding brain temperatures were 6.5 degrees +/-1.7 degrees C, 6.3 degrees +/-1.6 degrees C, and 4.2+/-1.3 degrees C cooler than the core, respectively. CONCLUSIONS: The magnitude of selective brain cooling observed in both study groups typically exceeded the 0.5 degrees to 2.0 degrees C change previously reported to modulate ischemic injury, and was most prominent during the latter phases of CPB. When compared with previous research from our laboratory, application of cold forced air to the cranial surface resulted in brain temperatures that were cooler than those observed during hypothermic CPB without pericranial cooling. On the basis of the assumption that similar beneficial brain temperature changes can be induced in humans, we speculate that selective convective brain cooling may enable clinicians to improve neurologic outcome after hypothermic CPB. 相似文献
100.
AG Baranovskii TG Kanyshkova AS Mogelnitskii VA Naumov VN Buneva EI Gusev AN Boiko TA Zargarova OO Favorova GA Nevinsky 《Canadian Metallurgical Quarterly》1998,63(11):1239-1248
It is known that in the blood of patients with some autoimmune diseases catalytically active antibodies hydrolyzing proteins, DNA, and RNA may be detected. In the present work homogeneous preparations of IgG antibodies (Ab) possessing high affinity for nucleic acids (NA) were obtained for the first time from blood and cerebrospinal fluid of patients with multiple sclerosis (MS). The fraction of IgG Ab as well as its Fab fragments and isolated light chains of both kappa- and lambda-types were shown to catalyze effectively the hydrolysis of DNA and RNA. It is shown by different methods that the capability for nucleic acid hydrolysis is an intrinsic property of the polyclonal Ab. NA-hydrolyzing Ab were detected in the blood of 69 of 72 and in the cerebrospinal fluid of 5 of 5 examined MS patients, while they were not detected in the blood of any of 50 healthy donors examined. Comparison of relative rates of RNA hydrolysis and of the substrate specificity in hydrolysis of various model RNAs--cCMP, poly(U), poly(A), and poly(C)--revealed pronounced differences of MS antibodies from ribonucleases of human blood, ribonuclease A, and all earlier described abzymes. The abzymes are usually characterized by relatively low specific activities in comparison with that of normal enzymes catalyzing analogous reactions. Ab from the blood of MS patients are the first example of autoabzymes whose specific activity in RNA hydrolysis is comparable or even higher than that of pancreatic ribonuclease A--one of the most active RNA-hydrolyzing enzymes. 相似文献