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991.
MJ Orloff MS Orloff SL Orloff B Girard 《Canadian Metallurgical Quarterly》1997,1(2):123-30, discussion 130-1
Organized thrombus in the main trunk of the portal vein was encountered in 85 (6.5%) of 1300 patients with cirrhosis and variceal hemorrhage who underwent direct portacaval shunt (PCS). The thrombus was successfully removed with restoration of portal blood flow in all patients by phlebothrombectomy and balloon catheter extraction. Of the 85 patients, 65 were among 400 unselected patients who underwent emergency PCS (16%), and 20 were among 900 selected patients who underwent elective PCS (2%). All patients were closely followed for at least 5 years. Patients with portal vein thrombosis (PVT) had more advanced liver disease than those without PVT, reflected preoperatively in significantly higher (P < 0.01) incidences of ascites (75%), severe muscle wasting (52%), varices of very large size (94%), the hyperdynamic state (94%), severe hypersplenism with a platelet count of less than 50,000/mm3 (92%), and placement in Child's class C (52%). Side-to-side PCS reduced the portal vein-inferior vena cava pressure gradient to a mean of 23 mm saline solution in patients with PVT, similar to the marked pressure reduction obtained in patients without PVT. PCS promptly stopped variceal bleeding in all patients in the emergency PCS group. Permanent prevention of recurrent variceal bleeding was successful in 95% of patients with PVT and more than 99% of patients without PVT. Survival rates were similar in patients with and without PVT. In patients with PVT, survival rates at 30 days and 1, 5, 10, and 15 years following emergency PCS were 69%, 66%, 65%, 55%, and 51%, respectively, and following elective PCS were 95%, 90%, 70%, 65%, and 60%, respectively. Quality of life was similar in patients with and without PVT. Long-term PCS patency was demonstrated yearly in 93% of patients in the group with PVT and in 99.7% of patients without PVT. Other similarities after 5 years between patients with and without PVT, respectively, were the incidences of recurrent encephalopathy (9% vs. 8%), alcohol abstinence (61% vs. 64%), improved liver function (68% vs. 62% to 75%), and return to work (52% vs. 56% to 64%). It was concluded that in patients with cirrhosis and variceal hemorrhage it is almost always possible to remove portal vein thrombus by means of phlebothrombectomy and then perform a direct PCS with results similar to those achieved in the absence of PVT. 相似文献
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995.
WG McKenna EJ Bernhard DA Markiewicz MS Rudoltz A Maity RJ Muschel 《Canadian Metallurgical Quarterly》1996,12(2):237-245
The high-affinity receptor (R) for IL-5 consists of a unique alpha chain (IL-5R alpha) and a beta chain (beta c) that is shared with the receptors for IL-3 and granulocyte macrophage colony stimulating factor (GM-CSF). We defined two regions of IL-5R alpha for the IL-5-induced proliferative response, the expression of nuclear proto-oncogenes, and the tyrosine phosphorylation of cellular proteins including beta c, SH2/SH3-containing proteins and JAK2 kinase. In the studies described here, we demonstrate that IL-5, IL-3 or GM-CSF stimulation induces the tyrosine phosphorylation of JAK2, and to a lesser extent JAK1, and of STAT5. Mutational analysis revealed that one of the proline residues, particularly Pro352 and Pro355, in the membrane-proximal proline-rich sequence (Pro352-Pro353-X-Pro355) of the cytoplasmic domain of IL-5R alpha is required for cell proliferation, and for both JAK1 and JAK2 activation. In addition, transfectants expressing chimeric receptors which consist of the extracellular domain of IL-5R alpha and the cytoplasmic domain of beta c responded to IL-5 for proliferation and tyrosine phosphorylation of JAK1. Intriguingly, electrophoretic mobility shift assay analysis revealed that STAT5 was activated in cells showing either JAK1 or JAK2 tyrosine phosphorylation. These results indicate that activation of JAK1, JAK2 and STAT5 is critical to coupling IL-5-induced tyrosine phosphorylation and ultimately mitogenesis, and that Pro352 and Pro355 in the proline-rich sequence appear to play more essential roles in cell growth and in both JAK1/STAT5 and JAK2/STAT5 activation than Pro353 does. 相似文献
996.
DC Nyam YH Ho F Seow-Choen AP Leong BR Parry MS Ho HS Goh 《Canadian Metallurgical Quarterly》1996,37(5):517-518
Inflammatory bowel disease is uncommon in Asians and reports of surgery in these populations are rare. Eighty-two patients with inflammatory bowel disease were seen in the Department of Colorectal Surgery over a five-year period (1989-1994). Twenty-three patients underwent surgery for their disease. There were 12 males and 11 females with 16 Chinese, 4 Indians and 3 Malays. Twelve had Crohn's disease and 11, ulcerative colitis. The majority of patients with Crohn's disease had emergency surgery for bleeding, perforation, abdominal masses and intestinal fistulae. Fifty percent of these had the diagnosis made intraoperatively or post-operatively. Surgery for ulcerative colitis was indicated because of multiple relapses, non-response to medical treatment, side effects of therapy or malignant change. The median age at surgery of patients with Crohn's disease and ulcerative colitis was 39 years (range 24-84) and 40 (range 18-60) respectively. The median follow-up was 22.4 months (range 9-50). The results of surgical therapy in these patients show that surgery when indicated can be done with minimum morbidity and mortality. 相似文献
997.
998.
Twenty-four patients had reconstruction of the distal aspect of the radius with use of an osteoarticular allograft, between 1974 and 1992, after excision of a giant-cell tumor (twenty patients), a desmoplastic fibroma (two patients), a chondrosarcoma (one patient), or an angiosarcoma (one patient). Nine giant-cell tumors were recurrent lesions, and eleven were extracompartmental primary lesions that had extended through the cortex or subchondral bone. The average age of the patients was 31.5 years (range, fifteen to sixty-one years); thirteen patients were female and eleven were male. Seventeen lesions involved the right wrist and seven involved the left wrist. The reconstruction was performed through a dorsoradial incision with use of a size-matched, preserved, fresh-frozen, distal radial allograft. All procedures included internal fixation and reconstruction of the radiocarpal ligaments. All patients were followed for a minimum of two years (average, 10.9 years; range, 2.1 to 22.3 years). At the time of follow-up, two patients -- one who had a giant-cell tumor and one who had a desmoplastic fibroma -- had a local recurrence. Eight patients needed a revision of the osteoarticular allograft, at an average of 8.1 years (range, 0.8 to 17.8 years) after the initial reconstruction. Seven of these patients had an arthrodesis and one had an amputation. The reason for the revision was a fracture of the allograft in four patients, recurrence of the tumor in one, pain in two, and volar dislocation of the carpus in one. There were fourteen other complications, including ulnocarpal impaction necessitating excision of the distal aspect of the ulna (four), painful hardware necessitating removal (four), rupture of the extensor pollicis longus tendon necessitating transfer of the extensor indicis proprius (two), fracture of the allograft necessitating open reduction and internal fixation (two), volar dislocation of the carpus necessitating closed reduction (one), and a ganglion of the dorsal aspect of the wrist necessitating excision (one). Of the sixteen patients in whom the osteoarticular allograft survived, three did not have pain, nine had pain in association with strenuous activities, and four had pain in association with moderate activities. Three patients reported no functional limitation, nine had limitation in the ability to perform strenuous activities, and four had limitation in the ability to perform moderate activities. The average range of motion of the wrist was 36 degrees of dorsiflexion, 21 degrees of volar flexion, 16 degrees of radial deviation, 15 degrees of ulnar deviation, 58 degrees of supination, and 72 degrees of pronation. Reconstruction of the distal aspect of the radius with use of an osteoarticular allograft was associated with a low rate of recurrence of the tumor, a moderately high rate of revision, little pain in association with common activities, good function, and a moderate range of motion. Osteoarticular allografts are an option for reconstruction of the distal aspect of the radius after excision of a malignant tumor or a recurrent or locally invasive benign lesion. 相似文献
999.
S Kubo MS Roh C Oyedeji MM Romsdahl K Nishioka 《Canadian Metallurgical Quarterly》1998,45(24):2270-2274
BACKGROUND/AIMS: Kupffer cells are the most important category of reticuloendothelial cells which are critical for host defense in the liver. We investigated the effects of tuftsin (Thr-Lys-Pro-Arg) on human Kupffer cells. METHODOLOGY: Human Kupffer cells were obtained from the livers of patients with colon cancer. Phagocytosis assay was done by microscopic counting of the number of Kupffer cells that engulfed fluorescent particle(s), and the number of the particles engulfed per Kupffer cell when Kupffer cells were incubated with and without tuftsin. Effect of tuftsin on the release of tumor necrosis factor from Kupffer cells was also studied. RESULTS: Phagocytosis was enhanced significantly by tuftsin. The greatest effect on percentage of phagocytic cells was observed at 1.0 microg/ml of tuftsin. The mean number of particles engulfed per Kupffer cell was also increased with tuftsin 1.0 microg/ml. Tumor necrosis factor release was also significantly increased; the greatest effect was observed at 1.0 microg/ml of tuftsin. CONCLUSIONS: Tuftsin enhances phagocytic activity and tumor necrosis factor release of human Kupffer cells, which are advantageous for host defense against invading microorganisms and tumor cells. 相似文献
1000.
Few health-related quality of life (HRQOL) survey instruments are available to the Chinese, although many have been developed for Western populations. This article describes the testing of the acceptability, conceptual equivalence, scaling assumptions and construct validity of a Chinese (HK [Hong Kong]) version fo the MOS SF-36 Health Survey. A Chinese (HK) SF-36 survey form was developed by an iterative translation process. It was administered to 236 Chinese subjects who also rated the understanding, difficulty, relevance, and acceptability of each question. The scores were tested against the original scaling assumptions. The SF-36 profile of our subjects was compared to U.S. results for conceptual equivalence. Most subjects did not have any problem in understanding and answering the SF-36. Item means were generally clustered as hypothesized. All but a few items satisfied all scaling assumptions. The shape of the eight-scale SF-36 profile was similar to that of American patients, suggesting conceptual equivalence. We conclude that the Chinese (HK) version of the SF-36 Health Survey has achieved conceptual equivalence and satisfied the psychometric scaling assumptions well enough to warrant further use and testing, using the standard scoring algorithms. 相似文献