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61.
62.
Stimulation of previously activated T cells through the antigenreceptor can result in the apoptotic death of the respondingcell, a process referred to as activation-induced cell death(AICD). This process appears to involve Fas (CD95) and tts ligand(Fas-L). The distribution of Fas and Fas-L on various T cellsubsets has not been extensively characterized. We have thereforeanalyzed cells committed to a Th1- or Th2-type differentiationpattern for the expression and function of Fas-L. Using botha sensitive bloassay and flow cytometry, we demonstrate thatcloned Th1 cells express high levels of Fas-L, whereas clonedTh cells express only low levels. The expression of Fas-L byTh1 and Th2 cells correlates with the relative abilities ofthese two cell types to undergo AICD. Whereas AICD is readilyobserved in cultures of cloned Th1, but not Th2 cells, Th2 cellsare capable of undergoing apoptosls in the presence of Th1 cellsexpressing Fas-L The ability of T cells to undergo AICD appearsto be unrelated to the presence of various cytokines. Thus,the Fas/Fas-L pathway appears to be critical for the inductionof AICD and this pathway is differentially regulated in cellscommitted to either Th1 or Th2 differentiation.  相似文献   
63.
A colorimetric enzyme amplification system was used to develop an immunoassay for human calcitonin (hCT) with a sensitivity of 6 pmol/l, and intra- and inter-assay CVs of 12% and 11.8% respectively for the low pool, and 10% and 11.2% for the high pool. The mean recovery of added synthetic hCT (58.5 pmol) from the plasma of 10 patients was 110% (64.4 pmol). The correlation coefficient between radioimmunoassay (RIA) and amplified enzymo-immunoassay was found to be 0.96 (p 0.001). The assay was successfully applied to the measurement of elevated calcitonin levels in plasma from patients with medullary carcinoma of the thyroid (MCT). AEIA offered a reliable and sensitive alternative to RIA for calcitonin determination with the added advantage of convenience as the label employed was much more stable.  相似文献   
64.
Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.
La valeur du sourcil cotyloidien comme repère d'analyse radiologique
Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.
  相似文献   
65.
66.
An enhanced chemiluminescent enzyme immunoassay for serum follicle stimulating hormone is described which involves sequential reaction of anti-follicle stimulating hormone antibody immobilised to the inside surface of an opaque microtitre plate with sample, monoclonal anti-alpha thyroid stimulating hormone antibody, and an anti-mouse IgG - horseradish peroxidase conjungate. Bound peroxidase activity was measured using a p-hydroxycinnamic acid enhanced chemiluminescent luminol-hydrogen peroxide reaction. The assay was sensitive (detection limit 0.01 mU/well) precise (intra-assay precision 2.5-8.1%, inter-assay precision 6.7-11.9%) and results obtained with this assay and a competitive radioimmunoassay were in good agreement (correlation coefficient 0.98).  相似文献   
67.
68.
A joint project between general practitioners and the South Eastern Health Board resulted in the establishment of a network of computerised practices collecting morbidity data in 1998 - 1999. Five practices established age sex registers for public and private patients. The International Classification of Primary Care 2 (ICPC-2) was used to define inclusion criteria for a range of illnesses relevant to primary care and public health. Problems arose in validating and extracting data in three practices. Disease prevalence for 17 illnesses was established for two practices only. The project clearly established the problems associated with morbidity data collection in general practice which include absence of a national patient registration system, absence of a national electronic messaging standard, difficulties extracting data from practice software systems and the need for a high level of dedicated staff and resources to implement such a project.  相似文献   
69.
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps.  相似文献   
70.
The Mater Misericordiae Hospital is a 575-bed tertiary referral centre with busy medical and surgical subspecialty services (including the national cardiac, cardiothoracic, spinal cord injury and pulmonary hypertension units). An audit of in-patient referrals to a neurology service was carried out over the twelve-month period of January to December 2002 inclusively. Five hundred and seventy seven inpatients were evaluated and managed in conjunction with the referring services. Consultation by the neurological service led to a significant contribution in the management of clinical cases in one of three ways: establishing a de novo diagnosis in patients admitted with active neurological symptoms where no working diagnosis exists (40.7% of referrals), significant alteration in diagnosis where the referring service have already established a specific working diagnosis (11.1% of referrals), or offering advice in the ongoing management of active neurological symptoms when the diagnosis is historically established and secure (48.2% of referrals). In order of frequency the most common reason for referral was stroke (131 cases (22.7%)), seizures unrelated to alcohol (59 cases (10.2%)), alcohol-related neurological problems (55 cases (9.5%)), movement disorders (41 cases (7.1%)), neuromuscular (40 cases (6.9%)), coma (35 cases (6%)), disorders of cognition (31 cases (5.3%)), acute headache (28 case (4.8%)) and functional neurological syndromes (26 cases (4.5%)). This audit highlights the value of a consulting neurology service in a multidisciplinary tertiary referral setting.  相似文献   
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