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11.
Minactivin expression in human monocyte and macrophage populations   总被引:4,自引:0,他引:4  
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone.  相似文献   
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IntroductionPatients with high-risk superficial transitional cell carcinoma (TCC) of the bladder have a lifelong risk of progression and require particular attention. Intravesical Bacillus Calmette-Guerin (BCG) is recommended as a first-choice adjuvant treatment to reduce the risk of progression of high-grade tumors and carcinoma in situ (CIS).ObjectivesTo evaluate the need for routine transurethral bladder biopsy from the site of previously resected tumor three months following intravesical BCG therapy, even if the urine cytology and cystoscopy were both negative.Subjects and methodsA prospective study was carried out on 45 patients of both genders presenting with superficial bladder cancer. All patients received a six-week course of intravesical BCG. The mean age of the patients was 59 (range 33–80) years. Three months following resection, urine cytology was negative in all patients. Cystoscopy was then performed and although it was negative for any suspicious lesions, a routine biopsy from the previous resection site was taken.ResultsThe indication for BCG instillation was T1G1 in 20 patients (44%), T1G2 in 12 patients (27%) and TaG2 in eight patients (18%). Three patients (7%) had a positive bladder biopsy for malignancy at follow-up despite the negative cystoscopy and cytology. There were no statistically significant differences between patients with positive and those with negative biopsies with regard to the stage and grade of the tumor before resection or the number of resected lesions. The original pathology of the three positive patients was T1G1 (two patients) and T1G2 (one patient). The pathology after BCG treatment was the same as before instillation, T1G1 (two patients) and T1G2 (one patient).ConclusionUntil more studies on larger numbers of patients are done, a routine biopsy from the site of previously resected tumor at the time of check cystoscopy may improve the detection of tumor recurrence.  相似文献   
13.
This is a retrospective study of 76 children who had had malignant tumours treated with laminectomy or laminoplasty and/or radiation therapy affecting the spine. Spinal tumours in children are extremely rare. However, their treatment can result in progressive spinal deformity. Radiation therapy affecting the growing spine can lead to asymmetric vertebral growth, causing kyphosis and/or scoliosis. These spinal deformities pose one of the most challenging problems for the spine surgeon. The aim of this article is to describe late-onset post-laminectomy/post-radiation spinal deformities and to evaluate the results of their treatment. Seventy-six children, with a mean age of 4 years and 7 months (range, 2 months to 16 years), underwent surgical removal of malignant tumours, between 1961 and 1995. Sixty-seven of them developed post-laminectomy/post-radiation spinal deformity. Conservative treatment consisted of bracing and corrective plaster casts. In 46 cases the deformity was treated surgically. A distraction plaster cast was used as preoperative preparation in the more severe and rigid curves, with or without neurological impairment. Surgery consisted of combined anterior and posterior fusion in 39 cases and posterior fusion in seven cases. Posterior instrumentation was used in 38 cases. The mean follow-up period was 6 years and 7 months (range, 9 months to 20 years and 2 months). Nine children did not develop deformity following the primary tumour treatment. One of them underwent laminectomy with posterolateral fusion and eight had laminoplasty combined with external immobilisation. Forty-six children developed iatrogenic kyphosis and underwent surgical correction from a mean of 75° pre-correction to a mean of 32°. The mean scoliotic angle correction was 66° preoperatively to 34° postoperatively. At follow-up, the mean correction loss was 7° in the sagittal plane and 5° in the coronal plane. Preoperative distraction plaster cast treatment resulted in a correction of 39% in kyphosis and of 58% in scoliosis, and in a partial or complete recovery of neurological deficits in all but one patient. In severe and rigid curves that develop following treatment of paediatric spinal tumours, preoperative application of a distraction plaster cast can reduce deformity and facilitate surgical correction. Furthermore, in the case of pure bony compression of the spinal cord due to the apical vertebra of the deformity, treatment with the distraction plaster can result in recovery from the neurological impairment. The prevention of post-laminectomy/post-radiation spine deformities is emphasised. Rigid external immobilisation for a period of 4 months in the cervical spine and of 6 months in the thoracic spine is recommended after both laminoplasty and laminectomy with posterolateral fusion.The research was carried out at Saint Vincent de Paul Hospital, Department of Pediatric Orthopaedic Surgery, Paris  相似文献   
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Background  

Although bacterial cholangitis is frequently mentioned as a cause of secondary sclerosing cholangitis, it appears to be extremely rare, with only one documented case ever reported.  相似文献   
17.
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
18.
AIDS and Behavior - Sexual transmission accounts for the majority of new HIV infections in Iran. More than 80% of HIV-positive persons are sexually active, and nearly 68% reported never using a...  相似文献   
19.
OBJECTIVES: This study was designed to determine the likelihood of harm in patients having additional delays before urgent coronary artery bypass graft (UCABG) surgery after percutaneous coronary intervention (PCI). BACKGROUND: Patients who have PCI at hospitals without cardiac surgery have additional delays to surgery when UCABG is indicated. METHODS: Detailed chart review was performed on all patients who had a failed PCI leading to UCABG at a large tertiary care hospital. A prespecified set of criteria (hemodynamic instability, coronary perforation with significant effusion or tamponade, or severe ischemia) was used to identify patients who would have an increased likelihood of harm with additional delays to surgery. RESULTS: From 1996 to 2000, 6,582 PCIs were performed. There were 45 patients (0.7%) identified to have UCABG. The demographic characteristics of the UCABG patients were similar to the rest of the patients in the PCI database, except for significantly more type C lesions (45.3% vs. 25.0%, p < 0.001) and more urgent cases (66.6% vs. 49.8%, p = 0.03) in patients with UCABG. Myocardial infarction occurred in eight patients (17.0%) after UCABG, with a mean peak creatine kinase of 2,445 +/- 1,212 IU/l. Death during the index hospital admission occurred in two patients. Eleven of the 45 patients (24.4%) were identified by the prespecified criteria to be at high likelihood of harm with additional delays to surgery. The absolute risk of harm is approximately one to two patients per 1,000 PCIs. CONCLUSIONS: Approximately one in four patients referred for UCABG would be placed at increased risk of harm if delays to surgery were encountered.  相似文献   
20.
Evaluation of candidate antiviral drugs against Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), and HHV-8 is hampered by the lack of convenient laboratory assays. We developed real-time quantitative PCR assays performed on supernatants of lymphoma cell lines and determined the 50% inhibitory concentrations (IC50s) of nucleoside, nucleotide, and pyrophosphate analogues against these herpesviruses.  相似文献   
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