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91.
This study examines the interrelationship between arachidonic acid (AA) metabolism and chemotactic potential of human peripheral blood neutrophils from both normal donors and patients with rheumatoid arthritis (RA). We demonstrate that there is a significant inverse relationship between the neutrophil's metabolic capability to produce [3H]LTB4 in response to ionophore A23187 stimulation versus the cell's chemotactic potential to optimal concentrations (i.e., 20 nM) of the chemotactic peptide f-Met-Leu-Phe as determined by leading front (r = 0.567, p = 0.009), mean depth (r = 0.458, p = 0.042), and population ratio (r = 0.471, p = 0.036) analyses. Subsequent Percoll density gradient studies revealed several RA neutrophil subpopulations exhibiting significantly enhanced (p less than 0.05) [3H] AA metabolism over corresponding density normal cells. Based on these results, we speculate that RA peripheral blood neutrophils have been "processed" to become less chemotactically-responsive yet more metabolically-active cells, and that the increased ability to produce LTB4 through both increased phospholipase A2 and lipoxygenase activities are part of the increased metabolic capabilities of the cell.  相似文献   
92.
CD14, a lipopolysaccharide (LPS) receptor, is present on the surface membrane of phagocytic leukocytes; it is also present in a soluble form in serum. Recently published results confer to this molecule novel functions that are linked to T-cell activation and to apoptosis. We report here that we have defined and characterized a novel lymphocyte population in human peripheral blood, a population that expresses an intracellular antigen detectable with MO2, a monoclonal antibody directed against the human CD14 molecule. This population is composed primarily of CD8-positive T-cells. We found surprisingly that this novel MO2-positive population of lymphocytes was greatly enhanced in asymptomatic, untreated HIV-positive individuals.  相似文献   
93.
The implementation of a national cervical screening programme in Ireland will require agreement on achievable standards in reporting cervical cytology similar to those published by the NHS cervical screening programme. Due to the opportunistic nature of screening in the Republic of Ireland, national incidence figures for uterine cervical disease are not available. An audit of our practice was performed to find the incidence of human papilloma virus related cervical disease in our population. Our laboratory reported 158,066 cases from 1996-2000. The overall rate of dyskaryosis increased from 3.6% to 7.9%, mostly due to increased low grade dyskaryosis (up from 2.3% to 6.0%). High grade dyskaryosis also increased (from 1.3% to 1.9%), particularly in the under-25 year age group who account for a growing proportion of high grade dyskaryosis (from 15.4% of all high grade diagnoses in 1996 to 23.0% in 2000). The positive predictive value of a diagnosis of high grade dyskaryosis remained stable between 76.0 and 79.5%. While opportunistic screening data may not be directly applicable to the entire screening population it is hoped that these data may form a foundation on which to estimate national incidence figures and define achievable standards for cervical screening cytology in Ireland.  相似文献   
94.
The case of a white-heroin addict who developed disseminated candidiasis following coinfection byCandida glabrata andCandida albicans is reported. Genomic random amplified polymorphic DNA typing suggested that theCandida glabrata blood isolates originated in the oral cavity of the patient. This case strengthens the evidence thatCandida species other thanCandida albicans can be involved in the pathogenesis of disseminated candidiasis in heroin addicts.  相似文献   
95.
Proteins of Rous sarcoma virus   总被引:32,自引:0,他引:32  
  相似文献   
96.
Lymphokine production by human milk lymphocytes.   总被引:3,自引:1,他引:3       下载免费PDF全文
To assess the functional capability of human milk lymphocytes, we studied phytohemagglutinin-induced lymphokine production by breast milk and, for comparison, peripheral blood lymphocyte cultures. Two lymphokines, lymphocyte-derived chemotactic factor (LDCF) and immune interferon, were assayed in supernatants of milk and blood lymphocyte cultures obtained from women 2 to 6 days postpartum. Eleven parallel milk and blood samples were studied for LDCF production. In nine experiments, both milk and blood lymphocytes produced LDCF. In the two other experiments, milk cells did not produce LDCF. In 10 milk cultures studied, all produced interferon activity. Acid and heat lability characteristics were typical of immune interferon. These results further characterize milk lymphocytes as immunologically competent and possibly important effector cells in neonatal immunity.  相似文献   
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Polymorphisms in exon 1 of the MBL-2 gene, resulting in reduced plasma levels of mannose binding lectin, were significantly overrepresented in 23 patients with primary antibody deficiency and culture-proven mycoplasma infections (P = 0.0038). This association persisted with the inclusion of a further nine suspected (doxycycline-responsive) cases (P = 0.0087). The lectin was shown to bind to three strains of mycoplasma.  相似文献   
100.
BACKGROUND: Continence services in the UK have developed at different rates within differing care models, resulting in scattered and inconsistent services. Consequently, questions remain about the most cost-effective method of delivering these services. AIM: To evaluate the impact of a new service led by a continence nurse practitioner compared with existing primary/secondary care provision for people with urinary incontinence and storage symptoms. DESIGN OF STUDY: Randomised controlled trial with a 3- and 6-month follow-up in men and women (n = 3746) aged 40 years and over living in private households (intervention [n = 2958]; control [n = 788]). SETTING: Leicestershire and Rutland, UK. METHOD: The continence nurse practitioner intervention comprised a continence service provided by specially trained nurses delivering evidence-based interventions using predetermined care pathways. They delivered an 8-week primary intervention package that included advice on diet and fluids; bladder training; pelvic floor awareness and lifestyle advice. The standard care arm comprised access to existing primary care including GP and continence advisory services in the area. Outcome measures were recorded at 3 and 6 months post-randomisation. RESULTS: The percentage of individuals who improved (with at least one symptom alleviated) at 3 months was 59% in the intervention group compared with 48% in the standard care group (difference of 11%, 95% CI = 7 to 16; P<0.001) The percentage of people reporting no symptoms or 'cured' was 25% in the intervention group and 15% in the standard care group (difference of 10%, 95% CI = 6 to 13, P = 0.001). At 6 months the difference was maintained. There was a significant difference in impact scores between the two groups at 3 and 6 months. CONCLUSIONS: The continence nurse practitioner-led intervention reduced the symptoms of incontinence, frequency, urgency and nocturia at 3 and 6 months; impact was reduced; and satisfaction with the new service was high.  相似文献   
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