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101.
A total of 814 isolates of the foodborne pathogen Campylobacter jejuni were characterized by multilocus sequence typing (MLST) and analysis of the variation of two cell-surface components: the heat-stable (HS) serotyping antigen and the flagella protein FlaA short variable region. We identified 379 combinations of the MLST loci (sequence types) and 215 combinations of the cell-surface components among these isolates, which had been obtained from human disease, animals, food, and the environment. Despite this diversity, 748 (92%) of the isolates belonged to one of 17 clonal complexes, 6 of which contained many (318, 63%) of the human disease isolates. Several clonal complexes exhibited associations with isolation source or particular cell-surface components; however, the latter were poorly predictive of clonal complex. These data demonstrate that the clonal complex, as defined by MLST, is an epidemiologically relevant unit for both long and short-term investigations of C. jejuni epidemiology.  相似文献   
102.
Until the 1980s, asbestos was widely used throughout the UK. The incidence of asbestos-related disease is still climbing because of the long delay in developing the disease from the initial exposure. The spectrum of diseases encompasses malignant mesothelioma, asbestosis, asbestos-related lung carcinoma and benign pleural disease, including pleural plaques.  相似文献   
103.
BACKGROUND: Vasogen Inc.'s (Mississauga, Ontario, Canada) immune modulation therapy (IMT) is a therapy in which cells from the patient's own blood are modified by ex vivo exposure to specific physicochemical stressors, including oxidation, ultraviolet (UV) light, and an elevated temperature. The therapy has been shown to have a beneficial effect in models of inflammation and vascular diseases. This study tested the hypothesis that IMT can prevent renal ischemia-reperfusion (I/R) injury in rats. METHODS: Whole blood was collected from syngeneic age-matched donors by cardiac puncture. It was treated with a combination of controlled physiochemical stressors consisting of elevated temperature, a gas mixture of medical oxygen containing ozone, and UV light. The treated blood (150 microL) was injected in the gluteal muscle. Control animals received the same volume of untreated blood or physiological saline. Transient (45 or 60 minutes) left-renal ischemia was produced with simultaneous contralateral nephrectomy in treated and control spontaneously hypertensive rats (SHR). Young and old male and female rats were studied. Plasma creatinine, diuresis, and the survival rates of each group were compared. Renal apoptosis-necrosis was estimated by DNA laddering, histology, and in situ terminal deoxynucleotidyl transferase assay. mRNA levels of several regulators of apoptosis-regeneration were determined in control and postischemic kidneys by Northern blotting. RESULTS: IMT pretreatment of SHR significantly reduced renal I/R injury compared with equivalent placebo treatments consisting of untreated blood- or saline-injected SHR, as evidenced by a significant increase of the survival rate curves in young and old male SHR, which correlated with 24-hour postischemic diuresis. The increases in plasma creatinine following renal I/R were significantly lower in IMT-treated young male and old female SHR compared with saline or untreated blood-injected controls. Dilution analysis showed that the protective effect of treated blood was lost by dilution. Loss of epithelial cells was reduced in IMT-treated rats, with a significant decline in the peak of apoptosis 12 hours after acute ischemic renal injury. IMT did not modify the pattern of mRNA levels of several genes involved in the inflammation and regeneration processes. CONCLUSION: Our data demonstrate that IMT prevents the destruction of kidney tissue and the resulting animal death caused by renal I/R injury.  相似文献   
104.
Systemic injection of lipopolysaccharide (LPS) blocks the expression of long-term potentiation in the hippocampus of the rat. This is coupled with increased IL-1beta concentration and c-Jun NH(2)-terminal kinase activity, as well as an increase in the number of cells displaying apoptotic characteristics in the hippocampus. Vasogen's Immune Modulation Therapy (IMT) is a procedure involving intramuscular administration of syngeneic blood which has been exposed ex vivo to elevated temperature, oxidation and ultraviolet light. We report that Vasogen's IMT significantly abrogates these LPS-induced effects with a concomitant increase in the concentration of the anti-inflammatory cytokine IL-10. These data suggest that Vasogen's IMT may play a protective role against the deleterious effects of immune insults in the brain.  相似文献   
105.
Fast neutron irradiation for prostate cancer   总被引:1,自引:0,他引:1  
The purpose of this study was to summarize the progress made using fast neutron irradiation in the treatment of prostate cancer at Wayne State University between 1991 and the year 2001. The results of three Phase II studies and one Phase III study involving nearly 700 patients is summarized in this paper. The Phase II studies were dose finding studies looking at doses of 15, 9, 10, and 11nGy, respectively. The randomized protocol was a study of sequence looking at the results of treating patients with neutron first versus neutron radiation last. The results demonstrated that the best combination of tumor control probabilities and normal tissue complications was found in a mix of approximately 50% neutrons and 50% photons. Thus, the standard doses become 10nGy and 40Gy of photons. The randomized trial demonstrated that the sequence has significant importance and the disease-free survival was 93% for patients treated with neutrons first versus 73% for patients treated with neutrons last. There was no difference in the rate of acute or chronic complications. Finally, an analysis was performed demonstrating which patients may best benefit from the use of neutron irradiation. It was shown that patients with one, two, or three adverse risk factors had a significant improvement in disease-free survival when part of the treatment included neutron radiation versus standard photon radiation alone. Neutron radiation can be delivered safely with effort to see that it is superior to that which can be achieved by conformal photon irradiation by itself. Future work will be done to expand the role of neutron radiation in other clinical disease sites.  相似文献   
106.
The authors' objective was to estimate the prevalence of major depressive disorder among Rwandans 5 years after the 1994 genocidal civil war. They interviewed a community-based random sample of adults in a rural part of Rwanda using the Hopkins Symptom Checklist and a locally developed functional impairment instrument. The authors estimated current rates of major depression using an algorithm based on the DSM-IV symptom criteria (A), distress/functional impairment criteria (C), and bereavement exclusionary criteria (E). They also examined the degree to which depressive symptoms compromise social and occupational functioning. Three hundred sixty-eight adults were interviewed, of whom 15.5% met Criteria A, C, and E for current major depression. Depressive symptoms were strongly associated with functional impairment in most major roles for men and women. The authors conclude that a significant part of this population has seriously disabling depression. Work on appropriate, feasible, safe, and effective mental health interventions should be a priority for this population.  相似文献   
107.
Postmastectomy radiation in patients with four or more positive nodes   总被引:1,自引:0,他引:1  
Timothy SK  Teng S  Stolier AJ  Bolton JS  Fuhrman GM 《The American surgeon》2002,68(6):539-44; discussion 544-5
Postmastectomy radiotherapy (PMR), a local therapeutic modality, is recommended to treat breast cancer patients with multiple involved axillary lymph nodes (a marker of increased systemic risk). Bothered by this conceptually flawed treatment approach we evaluated the impact of PMR on the treatment of women with four or more involved axillary lymph nodes. We identified 1164 patients treated from 1982 through 1999 with mastectomy. We reviewed the records of the 223 who demonstrated four or more positive axillary lymph nodes. Of these 128 were treated by mastectomy only and 95 by PMR. The mastectomy-only group demonstrated a mean tumor size of 3.5 cm, a median of seven axillary nodes involved, and a median of 24.9 nodes harvested. The PMR group had a mean tumor size of 4.3 cm with nine positive nodes out of a median total of 23.3 harvested. The difference in mean tumor size was statistically significant (P = 0.01). The locoregional recurrence (10.9% vs 12.6%), distant recurrence rates (42.2% vs 35.8%), and 5-year survival (51% vs 55%) were not statistically different between the mastectomy-only group versus the PMR group, respectively. Adding PMR to breast cancer treatment demonstrated no improvement in outcome. Despite limitations of this retrospective study the results strongly support evaluation of PMR by a high-quality randomized prospective trial.  相似文献   
108.
Steep learning curve of laparoscopic splenectomy   总被引:4,自引:0,他引:4  
BACKGROUND AND PURPOSE: In 1992, Ochsner Foundation Hospital was among the first institutions in which laparoscopic splenectomy was performed. The aim of this study is to review our experience and discuss the lessons learned. METHODS: A retrospective review of 33 cases of laparoscopic splenectomy for idiopathic thrombocytopenic purpura (ITP) (N = 22), autoimmune hemolytic anemia (AIHA) (5), thrombocytopenic purpura (TTP) (2), and other disorders (4) at Ochsner Foundation Hospital between 1992 and 1999 was conducted. Several measures, including rates of conversion to open splenectomy, were recorded and analyzed. RESULTS: Of the 33 cases, 26 (79%) were completed laparoscopically. Four were converted to an open procedure secondary to bleeding and three secondary to difficulty in dissection. Six conversions to open surgery were necessary during the first eight laparoscopic splenectomies and only one during our last 25 cases. Two patients required reoperations for bleeding. The average hospital stay after laparoscopic splenectomy was 2.3 days; eight patients stayed only 1 day. All of the TTP patients, 86% of the patients with ITP, and 40% of those with AIHA responded well to splenectomy. CONCLUSION: Laparoscopic splenectomy is a safe although complex procedure. Bleeding is the major complication but has been less common with experience. Even with today's technology, very large spleens are still extremely difficult to remove. With the short recovery and ready acceptance of patients and physicians, this technique is being used with increasing frequency. A significant learning curve exists for the safe completion of this challenging procedure.  相似文献   
109.
The objectives of this study were to investigate how Rwandans perceive the mental health effects of the 1994 genocide, to investigate the local validity of western mental illness concepts, and (if these concepts were found to be valid) to provide data to adapt existing mental health assessment instruments for local use. We used three ethnographic methods to interview people in two rural areas in Rwanda: first, free listing provided a list of local terms for mental symptoms and disorders; second, key informant interviews then provided more detailed information about these disorders; and finally, pile sorts confirmed the relationships among symptoms and disorders that emerged from the other methods. We found that interviewees described the diagnostic symptoms of depression and posttraumatic stress disorder as results of the genocide and also described associated "local" symptoms not included in the established diagnostic criteria. They divided symptoms into a "mental trauma" syndrome that included the posttraumatic stress disorder symptoms and some depression and local symptoms, and a grief syndrome that included other depression and local symptoms. In the pile sorts, we focused on investigating mood disorders and confirmed that four of the locally described symptoms formed part of a local depression-like illness. The results suggest that depression occurs among this population and support the local content validity of depression assessment instruments, such as the Depression section of the Hopkins Symptom Checklist. Similar independent evidence of validity is missing from most cross-cultural surveys. Our work supports the need and feasibility for collecting this supporting evidence prior to conducting cross-cultural surveys using existing instruments.  相似文献   
110.
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