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981.
982.
We analyzed retrospectively 1191 cases of bone graft harvesting of the iliac crest which had been performed at our hospital between 1982 and 1991. There was an operative revision rate of 2.8%. For further study, we analyzed the clinical reports of all autograft (iliac crest) donors in a representative year (1991) and re-examined all those who still had symptoms. A total of 104 grafts were taken from 97 patients. Of these, 18 developed postoperative complications (19.6%), such as hematoma, which could usually be treated with local procedures such as aspiration. The rate of hematoma tended to be lower in those patients who had received a local coagulant, but this was not significant. Of the patients 55% still had problems 1 year after operation at the time of re-examination, but in most cases they were minor, for example, local irritation or discomfort. Serious problems developed in those patients who had a palpable defect of the iliac crest. We advise using local coagulants to decrease the rate of postoperative complications, although we cannot statistically prove the effect. When large grafts are harvested, the iliac crest should be reconstructed for better long-term results. 相似文献
983.
The effects of prolactin (PRL) on proliferation of cultured human uterine leiomyoma-derived smooth muscle cells (SMC) and its mechanism of action were investigated. PRL stimulated DNA synthesis and the expression of PRL receptor was identified by ribonuclease protection assay. Moreover, the regulation of mitogen-activated protein (MAP) kinase by PRL in leiomyoma-derived SMC was investigated. PRL stimulated MAP kinase activity, as detected by 32P incorporation into MAP-2, in a dose-dependent manner. PRL also rapidly stimulated MAP kinase phosphorylation as detected by in vivo phosphorylation using 32P labeling and phosphotyrosine immunoblotting. These results suggest that PRL stimulates the proliferation of human leiomyoma cells via the MAP kinase cascade. 相似文献
984.
J Herlitz P Albertsson M Haglid BW Karlson M Hartford T Karlsson W Sandén 《Canadian Metallurgical Quarterly》1996,44(5):239-244
To derive and compare the need for hospitalization during 2 years prior to coronary artery bypass grafting (CABG) and 2 years after, all the patients from western Sweden in whom CABG without simultaneous valve surgery was performed between June 1988 and June 1991 were evaluated. Hospitalization prior to and after surgery was derived via questionnaires sent to the patients and via data from their hospital medical record forms. In all, 2099 patients were studied. The mean total number of days in hospital was 16 during the 2 years before and 24 including surgery and postoperative complications during the 2 years after the operation (p < 0.001). When the days for operation and postoperative complications were excluded, the mean number of days after operation was 7 (p < 0.001). Hospitalization due to myocardial infarction, angina pectoris, percutaneous transluminal coronary angioplasty and other investigations for heart disease were significantly reduced after CABG. On the other hand, hospitalization due to chest pain with causes other than ischemic heart disease, congestive heart failure, arrhythmias, and reoperation was more frequent during the 2 years after surgery. The total number of days in hospital was higher during the 2 years after CABG than during the 2 years before, despite the fact that hospitalization due to ischemic events was significantly reduced after the operation. 相似文献
985.
Nine feet in eight patients undergoing tarsometatarsal (Lisfranc) or other midfoot arthrodeses for posttraumatic or degenerative arthritis were reviewed retrospectively. All patients were treated using a medial one-third tubular plate spanning the midfoot joints to be fused. Three feet underwent fusion in situ while six feet underwent correction of residual planus, planovalgus, or cavovarus deformity at the time of fusion. All patients achieved fusion within 12 weeks. A good or excellent result was achieved in seven of nine feet. There was no radiographic or clinical evidence of pseudarthrosis or medial hardware failure in any patient. No patient to date has required hardware removal for a painful or prominent implant. The talus first metatarsal angle was improved an average of 15.5 degrees in the lateral plane and 10 degrees in the AP plane in patients undergoing deformity correction. The technique of using a medial plate for midfoot arthrodesis allows for reliable fusion in patients who require salvage for midfoot arthritis. This technique also allows for correction of deformity in patients with residual midfoot deformity. 相似文献
986.
NR Thomson A Cox BW Bycroft GS Stewart P Williams GP Salmond 《Canadian Metallurgical Quarterly》1997,26(3):531-544
The enteric bacterium Serratia marcescens is an opportunistic human pathogen. The strain ATCC39006 makes the red pigment, prodigiosin (Pig), and the beta-lactam antibiotic carbapenem (Car). Mutants were isolated that were concomitantly defective for Pig and Car production. These mutants were found to have a mutation in the rap gene (Regulation of Antibiotic and Pigment). Sequence analysis of the rap gene revealed a predicted protein product showing strong homology to SlyA, originally thought to be a haemolytic virulence determinant in Salmonella typhimurium. Homologues of rap were detected in several bacterial genera, including Salmonella, Yersinia, Enterobacter, and species of the plant pathogen, Erwinia. The Erwinia hoeEr (homologue of rap) and the Yersinia horYe genes were also found to be very similar to rap and slyA. Marker exchange mutagenesis of horEr revealed that it encoded a regulatory protein controlling the production of antibiotic and exoenzyme virulence determinants in the phytopathogen, Erwinia carotovora subspecies carotovora. We have shown that these new homologues of SlyA form a highly conserved subgroup of a growing superfamily of bacterial regulatory proteins controlling diverse physiological processes in human, animal and plant pathogens. 相似文献
987.
FD Niagro AN Forsthoefel RP Lawther L Kamalanathan BW Ritchie KS Latimer PD Lukert 《Canadian Metallurgical Quarterly》1998,143(9):1723-1744
Circoviruses are a diverse group of animal and plant pathogens with undefined relationships to one another but for their non-geminate, non-enveloped capsids and circular, single-stranded DNA genomes. The sequences of the beak and feather disease virus and porcine circovirus genomic DNAs are presented and analyzed in the context of the other members of the family. Sequence comparisons, inferred phylogenies, and geographic occurrence suggest that the ambisense circoviruses, particularly the beak and feather disease virus, represent an evolutionary link between the geminiviruses and the plant circoviruses. We propose that the family members be reclassified into three groups: The family Circoviridae consists of the animal pathogens (beak and feather disease virus and porcine circovirus) that possess ambisense genomes with striking similarities to the geminiviruses. The BBTV-like viruses include the plant pathogens (coconut foliar decay virus, banana bunchy top virus, subterranean clover stunt virus) with a geminivirus-like stem-loop element in their DNAs, and single to multiple component genomes. The chicken anemia virus is an unassigned virus possessing unique characteristics bearing little similarity to the other ssDNA viruses. 相似文献
988.
989.
BW Steinert DG Tang IM Grossi LA Umbarger KV Honn 《Canadian Metallurgical Quarterly》1993,54(1):92-101
Platelet eicosanoid metabolism resulting from tumor-cell-induced platelet aggregation (TCIPA) was examined in a homologous in vitro system. Rat Walker 256 carcinosarcoma cells induced the aggregation of rat platelets via a thrombin-dependent mechanism with concomitant production of eicosanoid metabolites (e.g., 12-HETE, TXA2). TCIPA was dependent on the concentration of tumor cells inducing aggregation, as well as cyclooxygenase and lipoxygenase products. Cyclooxygenase inhibitors, but not lipoxygenase inhibitors, blocked platelet aggregation induced in vitro by a low concentration of agonist. At a high agonist concentration, neither cyclooxygenase nor lipoxygenase inhibitors alone affected platelet aggregation; however, the combined inhibition of both the cyclooxygenase and lipoxygenase pathways resulted in subsequent inhibition of platelet aggregation regardless of agonist concentration. The extent of platelet TXA2 and 12-HETE biosynthesis was likewise dependent on and correlated with agonist concentration. The inhibitors used in this study did not significantly inhibit protein kinase C activity at the doses tested. Platelet surface glycoprotein alpha IIb beta 3 play an important role in platelet aggregation. The effect of platelet cyclooxygenase and lipoxygenase inhibition in regulating alpha IIb beta 3 surface expression was examined by flow cytometric analysis. Thrombin stimulation of washed rat platelets resulted in significantly increased surface expression of platelet alpha IIb beta 3 integrin complex. The enhanced surface expression was not inhibited by a cyclooxygenase inhibitor (aspirin), a thromboxane synthase inhibitor (CGS-14854) or a thromboxane receptor antagonist (SQ 29,548), nor was it stimulated by a thromboxane A2 mimic (pinane-thromboxane A2). However, alpha IIb beta 3 expression was blocked by lipoxygenase inhibition and stereospecifically increased by the platelet lipoxygenase metabolite 12(S)-HETE. These results suggest that both the platelet lipoxygenase and cyclooxygenase pathways are important for TCIPA but that different mechanisms of action are involved. 相似文献
990.
Papillary squamous cell carcinoma (PSCC) of the uterine cervix is a rare variant of squamous cell carcinoma (SCC). It is characterized by a papillary architecture and markedly atypical epithelium. Invasion and metastasis have been reported. We report a case of PSCC in a 72-year-old woman who subsequently tested positive for HPV 16. To our knowledge, this is the first report of HPV typing in a case of PSCC. Our finding of a high-risk HPV type in PSCC may help explain why PSCC has been reported to have a clinical course similar to that of nonpapillary SCC. 相似文献