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151.
Many isolates of Borrelia burgdorferi have been obtained from ticks and vertebrate tissues collected in North America and continental Europe but only one established culture of United Kingdom Borrelia burgdorferi has been recorded. In this paper we report the isolation of B. burgdorferi from one of 108 tick pools representing 733 ticks and eight-four tissue samples from twenty-six rodents collected in the U.K, and the subsequent failure to establish the isolate (from ticks collected in Fordingbridge) in culture. In contrast, using identical techniques and culture medium, B. burgdorferi was isolated from one of seven tick pools collected in Switzerland, and from a single pool of ticks collected in Slovakia, and both isolates were successfully passaged. Analysis of questing I. ricinus collected from Fordingbridge by direct immunofluorescence showed 6/32 (19%) of adults and 8/108 (7%) of nymphs were positive for B. burgdorferi, although only one nymph contained > or = 1000 spirochaetes. To examine further the problem of isolating U.K. B. burgdorferi, twelve Ixodes ricinus tick samples from Fordingbridge, a recognized focus of Lyme disease, were subjected to isolation and culturing techniques, and the procedures monitored by use of the polymerase chain reaction (PCR). Whereas 11/12 samples were PCR positive after 2 weeks in culture, only one was PCR positive after 4 weeks. Motile spirochaetes were not visible by dark-field microscopy in any of the cultures. The results indicate that the standard BSK II medium routinely used to isolate and culture B. burgdorferi does not readily support the replication of the Borrelia species endemic to the U.K. 相似文献
152.
BACKGROUND: This study aims to gain an understanding of treatment delays and their nature in initial psychotic episodes. We investigated to whom people turn for help, how long that approach takes and subsequent delays in commencing treatment. METHOD: Qualitative and quantitative methods were combined with interviews of 62 people suffering from first-episode psychoses, aged 16-30 years, who had recently accessed a specialist mental health service in Melbourne, Australia. A modified version of the World Health Organization Encounter Form was analysed in conjunction with other data. RESULTS: Pathways to care and the ways in which they were experienced were highly variable, with 50% of people experiencing psychotic symptoms before approaching any service. The general practitioner played a key role with 50% of people having had GP contact at some point prior to commencing effective treatment. Where an individual's own efforts to seek early help failed, the role of relatives and others was subsequently vital. CONCLUSIONS: Opportunities exist for shortening delays through targeted health promotion activities and professional training. The need is indicated for a multi-layered or topographical strategy to identify and minimise critical barriers on the route to early intervention. Refinement of interview techniques and instruments of measurement are needed to enhance the explanatory power of data collected. 相似文献
153.
MJ Whalen TM Carlos PM Kochanek SR Wisniewski MJ Bell JA Carcillo RS Clark ST DeKosky PD Adelson 《Canadian Metallurgical Quarterly》1998,15(10):777-787
Leukocyte-endothelial adhesion molecules, critical to the development of acute inflammation, are expressed in brain as part of the acute inflammatory response to traumatic brain injury (TBI). We measured the concentrations of the adhesion molecules P-selectin, ICAM-1, E-selectin, L-selectin, and VCAM-1 in ventricular cerebrospinal fluid (CSF) from children with severe TBI (Glasgow coma score < 8) and compared these findings with those from children with bacterial meningitis. P-selectin, an adhesion molecule associated with ischemia/reperfusion, was increased in children with TBI versus meningitis and control. Univariate and multivariate regression analyses demonstrated associations between CSF P-selectin and child abuse and age of < 4 years, and a significant, independent association between CSF intercellular adhesion molecule-1 (ICAM-1) and child abuse. These results are consistent with a specific acute inflammatory component to TBI in children. Future studies of secondary injury mechanisms and therapy after TBI should assess on the roles of P-selectin and ICAM-1 in injury and repair processes in brain after TBI. 相似文献
154.
155.
OBJECTIVE: To determine whether clinical parameters could be used to differentiate clinical mastitis (CM) caused by gram-positive bacteria from CM caused by gram-negative bacteria in dairy cows vaccinated against lipopolysaccharide core antigens. DESIGN: Case series. ANIMALS: 143 episodes of CM in 86 dairy cows in a single herd. PROCEDURE: Cows were examined at onset of CM, and 24 clinical parameters including rectal temperature, heart rate, rumen contraction rate, degree of dehydration, various udder and milk characteristics, lactation number, stage of lactation, and season of year were recorded. Milk production and milk constituent concentrations before onset of CM were obtained from Dairy Herd Improvement Association records. Values for cows with gram-negative CM were compared with values for cows with gram-positive CM. Logistic regression was used to identify important predictors of gram-negative CM. RESULTS: 64 (45%) CM episodes were caused by gram-negative bacteria and 79 (55%) were caused by gram-positive bacteria. Rumen contraction rate was significantly lower and milk protein percentage before onset of CM was significantly higher in cows with gram-negative, rather than gram-positive, CM. Logistic regression indicated that CM was more likely to have been caused by gram-negative bacteria if it developed during the summer, milk was watery, or rumen contraction rate was low. Sensitivity and specificity of the final regression model were 0.58 and 0.80, respectively. Predictive value of a positive result was 0.74 when proportion of CM episodes caused by gram-negative bacteria was assumed to be 50%. CLINICAL IMPLICATIONS: Results suggest that clinical observations do not allow accurate prediction of CM pathogens and should not be the sole criteria for deciding whether cows with CM are treated with antibiotics. 相似文献
156.
Limiting dilution assays to measure the frequency of interleukin-2-secreting peripheral blood T cells were carried out in patients, whose renal allografts had failed due to acute rejection (9 patients) and in patients whose grafts failed more than two years after transplantation without any recent evidence of acute rejection. Using a modified form of the assay we demonstrate that nearly half of 18 patients whose renal transplants had failed after more than two years have low or undetectable HTLp frequencies against donor, but not third-party DR antigens. No such difference was observed in any of the nine patients studied whose transplants were lost from early acute rejection. These results provide the first indication that, as in rodent models of transplantation, T cell unresponsiveness towards donor MHC antigens can occur following prolonged residence of an allograft in humans. Furthermore, the results suggest that chronic rejection may be driven by mechanisms other than direct allorecognition. The assay may be a valuable tool to study the evolution of donor-specific direct T cell alloresponsiveness in patients with well-functioning grafts. 相似文献
157.
PD Cullen 《Canadian Metallurgical Quarterly》1998,29(5):228-233
BACKGROUND: Acipimox, a derivative of nicotinic acid, lowers serum lipid levels by reducing the production of very-low-density and low-density lipoproteins (LDL). METHODS: We studied the additional lipid-lowering effect of high doses of acipimox in 12 patients with severe familial hypercholesterolemia (FH) who were on treatment with an HMG CoA reductase inhibitor, in some cases in combination with a resin. RESULTS: There was a significant reduction in total serum cholesterol (-9%), LDL-cholesterol (-9%) and serum triglycerides (-21%) when the standard doses of acipimox (750 mg/day) was added to treatment with simvastatin (and a resin). However, higher doses had no further hypolipidemic effect. In concordance with the reduction of serum cholesterol and LDL-cholesterol there was a significant decrease in apolipoprotein (apo)-B (-11%). There was no change in HDL-cholesterol, apo-A1 and lipoprotein(a). Acipimox in high doses up to 2250 mg/d was well tolerated except for initial gastric complaints and of flushing; because of these side effects one patient dropped out of the study. CONCLUSIONS: Acipimox in high doses, which were well tolerated, has no additional lowering effect on LDL-levels compared to the standard dose in patients with severe FH who are already treated with simvastatin. 相似文献
158.
Although the overall incidence of immunologic bullous diseases is comparatively low, they are nonetheless potentially lethal dermatologic disorders that occur most commonly in individuals age 55 and older. Thus familiarity with the signs, symptoms, and treatments will be valuable to the primary care physician. For bullous diseases in general, the challenge is to differentiate between those arising from immunologic rather than exogenous causes, such as drug-induced or drug-triggered pemphigus. Treatment goals include screening for associated malignancies, managing the lesions, and minimizing the morbidity and mortality associated with the disease. Collaboration with a dermatologist can aid in achieving these objectives. 相似文献
159.
160.
BACKGROUND: Intraoperative lymphatic mapping and identification of the first draining lymph node (the sentinel node) may allow some patients with breast cancer to avoid the morbidity of formal axillary clearance. The aim of this pilot study was to establish the reliability of the technique in predicting axillary node status. METHODS: Sixty-eight consecutive patients with breast cancer, 38 undergoing mastectomy and 30 wide local excision, were included. Some 2-4 ml of 2.5 per cent Patent Blue dye was injected into adjacent breast tissue on the axillary side of the primary tumour. After 5-10 min, the axilla was explored. Blue-stained lymphatics were dissected to the sentinel node, which was removed for frozen-section examination, followed by routine histology. Formal axillary dissection was then completed. RESULTS: A sentinel lymph node was identified successfully in 56 (82 per cent) of 68 patients. Histology of the sentinel node accurately predicted axillary node status in 53 (95 per cent). There were three false negatives (5 per cent). In each case, only a single non-sentinel node was tumour positive. Sensitivity and specificity were 83 and 100 per cent respectively. CONCLUSION: This technique would allow a selective policy of formal axillary dissection in only node-positive patients; however, further experience and refinement are needed. 相似文献