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Alexander E. Karu Tony H. Lin Leo Breiman Mark T. Muldoon Jean Hsu 《Food and Agricultural Immunology》1994,6(4):371-384
Quantitative competition immunoassays with appropriate combinations of antibodies give consistent dose‐response patterns which may be used to identify and estimate amounts of cross‐reacting compounds. Previously reported methods of analyzing cross‐reaction patterns include multiple regression, principal components analysis and minimum estimates of variance (MEV). Four other techniques which are preferable in theory have been surveyed: discriminant analysis (DA), maximum likelihood estimates (MLE), classification and regression trees (CART), and computational neural networks (NN). MLE and simple back‐propagation neural networks can estimate the concentration, as well as the identity, of individual compounds. These four methods worked well with unfitted, unscaled data from monoclonal assays of triazines, phenylureas and avermectins. Immunoassays must be properly designed to provide adequate data for pattern recognition. Cross‐reactivity pattern analysis will make multi‐analyte, multi‐antibody immunoassays feasible for many applications in toxicology and hazard assessment. 相似文献
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Dohle GR; Ramos L; Pieters MH; Braat DD; Weber RF 《Human reproduction (Oxford, England)》1998,13(3):620-623
Male genital tract obstructions may result from infections, previous
inguinal and scrotal surgery (vasectomy) and congenital bilateral absence
of the vas deferens (CBAVD). Microsurgery can sometimes be successful in
treating the obstruction. In other cases and in cases of failed surgical
intervention, the patient can be treated by microsurgical or percutaneous
epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction
(TESE) and intracytoplasmic sperm injection (ICSI). We present the results
of 39 ICSI procedures for obstructive azoospermia in 24 couples. The
aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD
in nine and genital infections in four. Sperm retrieval was accomplished
via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was
only applied when PESA failed to produce enough spermatozoa for
simultaneous ICSI. In six patients, the ICSI procedure was performed with
cryopreserved spermatozoa after an initial PESA procedure. Fertilization
occurred in 47% of the metaphase II oocytes; embryo transfer was performed
in 92% of procedures and resulted in a clinical pregnancy in 13/39
procedures. Ongoing pregnancy was achieved in 10/39 procedures. One
pregnancy was terminated early after prenatal investigation showed a
cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine
pregnancies resulted in the live birth of 10 children, without any
congenital abnormalities. Epididymal and testicular retrieved spermatozoa
were successfully used for ICSI to treat obstructive azoospermia, and
resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI
procedures, a success rate of 25.6% per treatment cycle and of 27.7% per
embryo transfer.
相似文献
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Use of Antibodies in Lymphocyte Secretions for Detection of Subclinical Tuberculosis Infection in Asymptomatic Contacts
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Rubhana Raqib S. M. Mostafa Kamal M. Jubayer Rahman Zeaur Rahim Sayera Banu Pradip K. Bardhan Fahima Chowdhury Gul Ara K. Zaman Robert F. Breiman Jan Andersson David A. Sack 《Clinical and Vaccine Immunology : CVI》2004,11(6):1022-1027
We have previously demonstrated that Mycobacterium bovis BCG-specific immunoglobulin G antibodies in lymphocyte secretions (ALS) can be employed as a marker for active tuberculosis (TB). We aimed to determine whether the ALS method allows detection of subclinical TB infection in asymptomatic individuals. A prospective study of family contacts (FCs) of patients with active TB and healthy controls was performed. Thirteen of 42 FCs had high ALS responses, including 6 FCs who subsequently developed active TB. No correlation was observed between the tuberculin skin test and the ALS responses in the FCs (r = 0.1, P = 0.23). Among patients with active TB, BCG-specific ALS responses steadily declined from the time of diagnosis through 6 months following antimycobacterial chemotherapy (P = 0.001). The ALS assay enabled detection of infection in exposed symptom-free contacts, who are at greater risk for developing active TB. The method may also allow discrimination between effective treatment of active infection and suboptimal response to therapy. 相似文献
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L1 knockout mice show dilated ventricles, vermis hypoplasia and impaired exploration patterns 总被引:8,自引:3,他引:8
Fransen E; D'Hooge R; Van Camp G; Verhoye M; Sijbers J; Reyniers E; Soriano P; Kamiguchi H; Willemsen R; Koekkoek SK; De Zeeuw CI; De Deyn PP; Van der Linden A; Lemmon V; Kooy RF; Willems PJ 《Human molecular genetics》1998,7(6):999-1009
L1 is a neural cell adhesion molecule mainly involved in axon guidance and
neuronal migration during brain development. Mutations in the human L1 gene
give rise to a complex clinical picture, with mental retardation,
neurologic abnormalities and a variable degree of hydrocephalus. Recently,
a transgenic mouse model with a targeted null mutation in the L1 gene was
generated. These knockout (KO) mice show hypoplasia of the corticospinal
tract. Here we have performed further studies of these KO mice including
magnetic resonance imaging of the brain, neuropathological analysis and
behavioral testing. The ventricular system was shown to be abnormal with
dilatation of the lateral ventricles and the 4th ventricle, and an altered
shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the
KO mice is hypoplastic. Their exploratory behavior is characterized by
stereotype peripheral circling reminiscent of that of rodents with induced
cerebellar lesions.
相似文献
10.
A community outbreak of Legionnaires' disease linked to hospital cooling towers: an epidemiological method to calculate dose of exposure. 总被引:1,自引:0,他引:1
C M Brown P J Nuorti R F Breiman A L Hathcock B S Fields H B Lipman G C Llewellyn J Hofmann M Cetron 《International journal of epidemiology》1999,28(2):353-359
BACKGROUND: From July to September 1994, 29 cases of community-acquired Legionnaires' disease (LD) were reported in Delaware. The authors conducted an investigation to a) identify the source of the outbreak and risk factors for developing Legionella pneumophila serogroup 1 (Lp-1) pneumonia and b) evaluate the risk associated with the components of cumulative exposure to the source (i.e. distance from the source, frequency of exposure, and duration of exposure). METHODS: A case-control study matched 21 patients to three controls per case by known risk factors for acquiring LD. Controls were selected from patients who attended the same clinic as the respective case-patients. Water samples taken at the hospital, from eight nearby cooling towers, and from four of the patient's homes were cultured for Legionella. Isolates were subtyped using monoclonal antibody (Mab) analysis and arbitrarily primed polymerase chain reaction (AP-PCR). RESULTS: Eleven (52%) of 21 case-patients worked at or visited the hospital compared with 17 (27%) of 63 controls (OR 5.0, 95% CI : 1.1-29). For those who lived, worked, or visited within 4 square miles of the hospital, the risk of illness decreased by 20% for each 0.10 mile from the hospital; it increased by 80% for each visit to the hospital; and it increased by 8% for each hour spent within 0.125 miles of the hospital. Lp-1 was isolated from three patients and both hospital cooling towers. Based on laboratory results no other samples contained Lp-1. The clinical and main-tower isolates all demonstrated Mab pattern 1,2,5,6. AP-PCR matched the main-tower samples with those from two case-patients. CONCLUSION: The results of our investigation suggested that the hospital cooling towers were the source of a community outbreak of LD. Increasing proximity to and frequency of exposure to the towers increased the risk of LD. New guidelines for cooling tower maintenance are needed. Knowing the location of cooling towers could facilitate maintenance inspections and outbreak investigations. 相似文献