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21.
Follow-up study after dynamic and static stabilisation of the lumbar spine   总被引:5,自引:0,他引:5  
INTRODUCTION: The clinical indication for graf's ligamentoplasty and dorsoventral fusion may be described as the "lumbar instability syndrome". A follow-up comparison between Graf's ligamentoplasty and instrumental dorsoventral fusion in a consecutive series of 52 patients was performed. METHODS: 52 patients operated on for low back pain were recalled for a clinical and radiological review (at mean 79 months postoperatively). 26 patients underwent Graf' ligamentoplasty and 26 patients underwent dorsoventral fusion. We evaluated the surgical results and measured an objective outcome using the Oswestry Score, Low Back Outcome Score (LBOS) and Visual Analogue Scale (VAS). For radiological evaluation the Mimura and the Pathria Scores were used. RESULTS: There was no statistically significant difference between the two groups, when measured by the Oswestry Score, LBOS and VAS at the latest follow-up. The difference between the preoperative and actual VAS in each group was statistically significant (p < 0.001). Furthermore, there was no provable preoperative parameter in favour of either one of these therapies. CONCLUSION: Both methods for stabilisation methods of the lumbar spine had a comparable clinical outcome.  相似文献   
22.
PURPOSE: The shape of the dose-effect curve for neutrons, i.e. the question as to whether the curve is linear or supralinear in the low-dose region, is still not clear. Therefore, the mutagenic effect of very low doses of low-energy neutrons was determined. MATERIALS AND METHODS: Human-hamster hybrid A(L) cells contain human chromosome 11, which expresses the membrane protein CD59. This membrane protein can be detected immunologically and quantified by flow cytometry. The A(L) cells were irradiated with neutrons of 0.565, 2.5 or 14.8 MeV and the results were compared with those after 200 kVp X-rays. Before irradiation, cells spontaneously mutated in the CD59 gene were removed by magnetic cell sorting (MACS). RESULTS: The relative biological effectiveness (RBE) for CD59 mutation induction was 19.8 (+/-2.7) for 0.565 MeV, 10.2 (+/-1.9) for 2.5 MeV, and 10.2 (+/-1.6) for 14.8 MeV neutrons. Linear mutation responses were obtained with all radiations except for 14.8 MeV neutrons where a supralinear curve may be a better fit. The deletion spectrum of mutated cell clones showed 29 Mbp deletions on average after irradiation with 0.069 Gy of 0.565 MeV neutrons. This scale of deletions is similar to that after 3 Gy 100 kV X-rays (=34 Mbp). For 50% cell survival, the RBE of the neutrons was 11 compared with 200 kV X-rays. CONCLUSIONS: Neutrons of low energies (0.565 or 2.5 MeV) produce a linear dose-response for mutation in the tested dose range of 0.015-0.15 Gy. The neutron curve of 14.8 MeV can be approximated by a curvilinear or linear function.  相似文献   
23.
Adapting to living with coeliac disease requires individuals to learn about and follow a strict gluten-free diet. Utilising a qualitative inductive approach, this study aimed to explore the perspectives of adults diagnosed with coeliac disease who have accessed dietetic services in a rural outpatient setting. A purposive sample of adults with coeliac disease who had accessed dietetic services from two rural dietetic outpatient clinics were recruited. Semi-structured interviews were conducted by telephone. Data were thematically analysed. Six participants were recruited and interviewed. Three key themes emerged: (i) optimising individualised support and services, (ii) adapting to a gluten-free diet in a rural context, and (iii) managing a gluten-free diet within the context of interpersonal relationships. Key issues identified in the rural context were access to specialist services and the increased cost of gluten-free food in more remote areas. The findings of this study have highlighted the difficulties associated with coeliac disease management and how dietetic consultation has the potential to influence confidence in management and improve lifestyle outcomes. Further qualitative research is required to expand on the findings of this study and inform future dietetic practice that meets the expectations and individual needs of people with coeliac disease in rural settings.  相似文献   
24.
Two monoclonal antibodies have been developed that bind to a shed bladder tumor-associated antigen. Preliminary data have demonstrated that antigen-positive tumors shed detectable amounts of antigen in the urine while antigen-negative tumors do not. This antigen may be differentially metabolized by normal and malignant urothelial cells. Further characterization of this antigen and its evaluation as a urinary marker for antigen positive bladder cancers is continuing.  相似文献   
25.
Improved growth of human urothelial carcinoma cell cultures   总被引:4,自引:0,他引:4  
From January, 1981 through June, 1982 specimens from 21 patients with bladder (urothelial) cancer were placed in tissue culture, and one long term cell line was established (5%). From July, 1982 through February, 1984, using an improved culture medium, seven long term cell cultures were established from 21 patients (33%). In addition, one long term culture from a patient with a bladder melanoma was established using the standard culture medium. The nine cell cultures were derived from the following types of tumors: transitional cell carcinoma (6), adenocarcinoma (1), squamous cell carcinoma (1) and melanoma (1). All of the cell lines have produced tumors in athymic nude mice except for one transitional cell carcinoma. All of the cultures demonstrate aneuploidy. Homogeneously staining regions have been seen in some cell cultures. A common marker chromosome has not been identified.  相似文献   
26.
Background. B-cell depletion with rituximab, a chimeric anti-CD20antibody, is a novel treatment for refractory and relapsingANCA-associated small-vessel vasculitis. Data are limited andmost reports describe single patients or small numbers of patientsfollowed prospectively. Methods. We report a single-centre experience with 15 patientswho received rituximab for refractory or relapsing ANCA-associatedvasculitis. All patients had been treated with corticosteroidsand cyclophosphamide and a variety of other second-line immunosuppressiveagents. None of the patients had evidence of infection and receivedfour infusions of 375 mg/m2 of rituximab. Disease activity wasassessed in accordance with the Birmingham Vasculitis ActivityScore (BVAS). BVAS, C-reactive protein and ANCA titres wererecorded at baseline and during follow-up. Results. B-cell depletion was achieved in all patients. Partialor complete remission was seen in 14 of 15 patients with a significantdecline in BVAS compared to baseline (P < 0.007). One patientwith granulomatous ANCA-associated vasculitis did not respondto rituximab. There were no side effects during rituximab infusion.Transient leucopenia was observed in two patients. One patientwith bronchial stenosis died of pneumonia 5.5 months after theinitiation of rituximab treatment. One initially anti-HBc-positive/HBsAg-negativepatient experienced a reactivation of hepatitis B, developedend-stage renal failure and died after refusal of dialysis. Conclusions. We report the largest case series of rituximabuse for ANCA-associated vasculitis so far. Our data supportthat the drug is capable of inducing partial or complete remissionin refractory or relapsing patients. Leucopenia and infectiouscomplications remain a matter of concern.  相似文献   
27.
28.
OBJECTIVE: Acute cryptogenic hepatitis may represent both a self-limited disease as well as the onset of chronic hepatitis. The aim of this analysis was to evaluate the effect of steroid treatment in patients with acute cryptogenic hepatitis. METHODS: We retrospectively analyzed four patients with acute cryptogenic hepatitis. Histories were negative for alcohol and hepatotoxic drug intake. Markers of metabolic liver disease, liver-related autoantibodies, and viral markers were negative in all patients. Gamma globulins were in the normal range. ALT rose above 1000 U/L in all patients and bilirubin levels were elevated to more than 400 micromol/L. Histopathological assessment revealed minimal infiltration with plasma cells, eosinophils and bile duct lesions. Using the international scoring system for the diagnosis of autoimmune hepatitis, all patients were classified as 'probable disease' in the absence of specific markers. RESULTS: We started immunosuppressive treatment with prednisolone because of persisting high aminotransferases and impaired liver function. All patients responded to steroids with normalization of liver function and a rapid decrease of aminotransferases. In one patient, additional treatment with azathioprine was necessary due to rebounding aminotransferases during steroid tapering. CONCLUSION: Steroids have to be taken into account in the therapy for severe acute cryptogenic hepatitis. The response to steroid treatment could be indicative for an autoimmune genesis of the disease.  相似文献   
29.
BACKGROUND: Allograft anterior cruciate ligament reconstruction provides benefits such as earlier return to activities and less pain, but concerns remain regarding potential infection and biomechanical stability. HYPOTHESIS: There is no difference in biomechanical properties of soft tissue allografts treated with the Biocleanse tissue sterilization process compared with irradiated and fresh-frozen allografts. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty-six tibialis anterior allografts were equally divided between Biocleanse, irradiated, and fresh-frozen groups. Grafts were measured for cross-sectional area and looped over a smooth rod with the free sutured ends of the graft fixed in custom clamps. Specimens were tensioned to 10 N for 2 minutes and then loaded between 50 and 300 N for 1000 cycles followed by a failure test. Data for creep (mm); stiffness (N/mm) at cycles 1, 10, 100, and 1000; failure load (N); and failure stress (MPa) were compared with a one-way analysis of variance (P < .05). RESULTS: There were no statistically significant differences in creep between groups. Sterilized groups (irradiated = 144.7 +/- 17.7 N/mm and Biocleanse = 146.5 +/- 28.2N/mm) were significantly stiffer during the first cycle than the fresh-frozen group (117.8 +/- 15.7 N/mm, P < .005) without statistically significant differences for subsequent cycles. There were no differences between groups for either failure load (fresh-frozen = 1665 +/- 291.3 N, irradiated = 1671.9 +/- 290.2 N, Biocleanse = 1651.6 +/- 377.4 N) or failure stress. CONCLUSION: Data for "time-zero" physiologic stiffness and failure loads indicate that the Biocleanse process does not adversely affect the biomechanical properties of the allograft material. CLINICAL RELEVANCE: This novel sterilization technique may provide surgeons with potential allograft material with similar biomechanical properties to native tissue.  相似文献   
30.
Background/Aims: The incidence of hepatic granulomas is reported in 2–15% of liver biopsies. This study was carried out to evaluate the incidence and aetiology of hepatic granulomas in a German Institute of Pathology with specialization in liver diseases. Methods: A retrospective case review was performed on 12 161 liver biopsies of the Institute of Pathology (University of Cologne) between 1996 and 2004. Aetiology was determined according to histomorphological changes, clinicopathological data and liver tissue polymerase chain reaction (PCR) for detection of diverse putative pathogens in the liver tissue. Results: Four hundred and forty‐two liver biopsies revealed granulomatous lesions (3.63%). Two hundred and fifteen cases (1.77% of all biopsies and 48.64% of granulomatous lesions) were diagnosed as primary biliary cirrhosis. In 37 cases (0.3% of all biopsies and 8.37% of granulomatous lesions), the diagnosis of sarcoidosis was established. A positive PCR result for an infectious pathogen was obtained in 15 samples (3.39%) [Bartonella henselae (n=2), Listeria (n=3), Mycobacterium tuberculosis (n=3), Yersinia pseudotuberculosis (n=1), cytomegalovirus (n=2), Epstein–Barr virus (n=4)]. In six cases, a putative diagnosis was established according to the report of clinical conditions. In 11 cases (2.48%), drugs were the putative causative agent. In 158 cases (36%) a definite diagnosis could not be established. Conclusions: Hepatic granulomas have a broad range of underlying aetiologies. With a combined histological, clinical, serological, and molecular approach, we were able to clarify the cause in 64% of the cases. Owing to the diverse prognosis and therapeutic implications, a detailed interdisciplinary workup of all liver biopsies with granulomatous lesions is mandatory.  相似文献   
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