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排序方式: 共有900条查询结果,搜索用时 15 毫秒
31.
Sunyer J Garcia-Esteban R Castilla AM Aurrekoetxea JJ I?iguez C Tardón A Espada M Lertxundi A Chatzi L Rebagliato M Kogevinas M;INMA project 《The European respiratory journal》2012,40(2):371-376
Tobacco consumption and exposure to second-hand smoke (SHS) are associated with reduced birth weight. One issue that has not been clarified previously is that of the potential higher risk of this outcome in mothers with asthma. We assessed the role of prenatal maternal tobacco use and SHS on reproductive outcomes and assessed the interaction with maternal history of asthma. Data was collected from the INMA study, a maternal birth cohort selected from the general population established in Spain in 2002. We measured cotinine at the 32nd week of pregnancy in 2,219 females. Diagnosed maternal asthma was self-reported during pregnancy. 35% of mothers reported not being exposed to smoking or SHS during pregnancy. Active smoking (i.e. self-reported or cotinine >50 ng·mL(-1)) was related to a 134 g decrease in birth weight and a relative risk of 1.8 for small for gestational age and fetal growth restriction. These results were not modified by maternal asthma. Maternal asthma had a similar frequency in all exposure groups. Non SHS-exposed females had the lowest prevalence of asthma. SHS (i.e. cotinine 20-50 ng·mL(-1)) decreased birth weight by 32 g among those without maternal asthma, but these differences were not statistically significant (95% CI -88.76-24.76). Maternal asthma did not promote these effects. Maternal history of asthma did not modify the effects of smoking on reproductive outcomes in a cohort sampled from the general population. 相似文献
32.
Pastora Martínez‐Castilla 《Clinical linguistics & phonetics》2013,27(4-5):363-370
This study aimed to find out what intonation features reliably represent the emotions of “liking” as opposed to “disliking” in the Spanish language, with a view to designing a prosody assessment procedure for use with children with speech and language disorders. 18 intonationally different prosodic realisations (tokens) of one word (limón) were recorded by one native Spanish speaker. The tokens were deemed representative of two categories of emotion: liking or disliking of the taste “lemon”. 30 native Spanish speakers assigned them to the two categories and rated their expressiveness on a six‐point scale. For all tokens except two, agreement between judges as to category was highly significant, some tokens attracting 100% agreement. The intonation contours most related to expressiveness levels were: for “liking”, an inverted U form contour with exaggerated pitch peak within the tonic syllable; and for “disliking”, a flat melodic contour with a slight fall. 相似文献
33.
Barreiro P Castilla JA Labarga P Soriano V 《Human reproduction (Oxford, England)》2007,22(9):2353-2358
The remarkable reduction in HIV-related morbidity and mortality as a consequence of the widespread use of highly active antiretroviral therapy (HAART) has led to a growing number of HIV-infected persons and their partners requesting counselling regarding the chances of reproduction. A thoughtful medical evaluation of the couple, which should entail HIV status, screening for genital infections and fertile potential, is needed before considering any reproductive attempt. Given that both sexual and perinatal transmission of HIV is directly correlated with the level of viral replication, being almost negligible in patients with undetectable viremia, HAART should be given to the infected partner to minimize the risk of transmission. Assisted reproduction after 'sperm washing' may further reduce the chances of infection, although this is not within reach or desire for a significant number of HIV-serodiscordant couples. From our perspective, natural conception could now be considered a possible alternative for HIV-serodiscordant couples, as long as complete suppression of viremia with HAART is achieved in the infected partner. The objective of this paper is to propose a protocol that may minimize risks in HIV-discordant couples that have opted for natural conception. 相似文献
34.
Melvin LH Ling BMed MD Jason Yosar MBBS Brendon WH Lee BMed Saumil A Shah BMed MD Ivy W Jiang BMed Anna Finniss FRACP Alexandra Allende FRCPA PhD Ian C Francis FRACS FRANZCO PhD 《Clinical & experimental optometry》2020,103(5):572-582
Temporal arteritis (TA), or giant cell arteritis, is a systemic autoimmune vasculitis affecting patients over 50 years of age. It can cause rapid, irreversible bilateral vision loss in older adults and is therefore considered an ophthalmological emergency. Many of the symptoms and signs of TA can be vague, non-specific and gradual in onset, often leading to a delayed or inaccurate diagnosis. As such, it is important for a wide variety of primary optometrists and health practitioners to maintain a robust understanding of the clinical presentation, key investigations and time-sensitive management of this disease, as early initiation of treatment for TA can be vision- and life-saving. 相似文献
35.
del Romero J Marincovich B Castilla J García S Campo J Hernando V Rodríguez C 《AIDS (London, England)》2002,16(9):1296-1297
We analysed a cohort of heterosexual HIV- serodiscordant couples with the aim of evaluating the risk of transmission ascribed to unprotected orogenital intercourse. A total of 135 seronegative individuals (110 women and 25 men), whose only risk exposure to HIV was unprotected orogenital sex with their infected partner, registered 210 person-years of follow-up. After an estimated total of over 19,000 unprotected orogenital exposures with the infected partner not a single HIV seroconversion occurred. 相似文献
36.
de Koning JP; Dong F; Smith L; Schelen AM; Barge RM; van der Plas DC; Hoefsloot LH; Lowenberg B; Touw IP 《Blood》1996,87(4):1335-1342
37.
Expression of platelet-derived growth factor and its receptors by two pre-B acute lymphocytic leukemia cell lines 总被引:1,自引:0,他引:1
Platelet-derived growth factors (PDGF) are potent regulators of cell proliferation. The three isoforms of PDGF AA, AB, and BB are encoded by two genes: PDGF A and PDGF B. The v-sis oncogene is homologous to the PDGF-B gene. v-sis can transform cells that express the appropriate PDGF receptors. Two different types of receptors, PDGF-alpha and PDGF- beta, also encoded by two genes, have been identified. We show that two cell lines. SMS-SB and NALM-6, both derived from pre-B-cell acute lymphocytic leukemias, express the PDGF-A chain gene, and one of them, SMS-SB, releases PDGF-A chains into the media. The SMS-SB cells also express the PDGF-beta receptor, whereas NALM-6 cells express the PDGF- alpha receptor and bind PDGF. This extends the possible targets for PDGF to the B-cell lineage lymphocytes. 相似文献
38.
In vivo release and turnover of secreted platelet antiheparin proteins in rhesus monkey (Macaca mulatta) 总被引:1,自引:0,他引:1
Musial J; Niewiarowski S; Edmunds LH Jr; Addonizio VP Jr; Nicolaou KC; Colman RW 《Blood》1980,56(4):596-607
Human and rhesus monkey platelets secrete at least two antiheparin proteins: platelet factor 4 (PF4) and low affinity platelet factor 4 (LA-PF4). Neither of these proteins showed species-related antigenic differences. As determined by radioimmunoassay, the levels of PF4 and LA-PF4 antigen per 10(9) monkey platelets amounted to 10.7 and 20.3 microgram, respectively. One milliliter of monkey plasma prepared from blood collected into an anticoagulant composed of EDTA, prostaglandin E1, and theophylline solution contained 22.4 ng LA-PF4 and 8.0 ng PF4. Concentrations of these two platelet-specific proteins in monkeys closely resembled levels found in human platelets and plasma. Infusion of prostacyclin (PGI2) (100 or 300 ng/kg/min) into monkeys for 15 min resulted in a significant decrease of plasma levels of LA-PF4 antigen and of PF4 by 40%--60% (p < 0.0001). This decrease was related to the inhibitory effect of PGI2 on the secretion of platelets stimulated by a catheter or by venipuncture. Longer infusion of PGI2 did not produce further significant change. The supernate obtained after aggregation of human platelets stimulated by thrombin was injected into monkeys receiving PGI2 infusion. The disappearance of LA-PF4 antigen in monkey plasma followed a biphasic exponential curve with half-lives for the fast and slow components of 8.4 and 63 min. PF4 disappeared faster but followed the same pattern (half-lives for the fast and slow component of 2.1 and 70 min). Analysis of the experimental data suggests that the low levels of secreted platelet proteins in monkey plasma are related to their minimal in vivo release and to their rapid clearance. 相似文献
39.
Aitziber Aguinaga Jorge Díaz-González Alejandra Pérez-García Laura Barrado Iván Martínez-Baz Itziar Casado Regina Juanbeltz Carmen Ezpeleta Jesús Castilla 《Enfermedades infecciosas y microbiología clínica》2018,36(6):325-331
Objective
To estimate the prevalence of hepatitis C virus (HCV) infection in Navarra, Spain, as well as to distinguish between diagnosed and undiagnosed infections.Methods
A study was conducted on patients scheduled for surgery unrelated to HCV infection. They were all tested for HCV antibodies, under a routine scheme, from January 2014 to September 2016. Patients with a positive result by enzyme immunoassay were confirmed using immunoblot and/or HCV-RNA. Previous laboratory results were also taken into account. The prevalence was adjusted to the sex and age structure of the Navarra population.Results
The study included a total of 7,378 patients with a median age 46 years, of whom 50% women. HCV antibodies were detected in 69 patients, which is a prevalence in the population of 0.83% (95% confidence interval: 0.64-1.05), and was higher in men (1.11%) than in women (0.56%; P = .0102). Among the HCV positive patients, 67 (97%) had had another previous positive result. Population prevalence of previous positive HCV was 0.80%, and was 0.03% for a new diagnosis. Of the HCV positive patients, 78% had detectable HCV-RNA. It was estimated that 0.65% of the population had had detectable HCV-RNA, and 0.51% continued to have it when recruited into the study.Conclusion
Previous estimates of prevalence of HCV infection should be revised downwards. Only a small proportion of HCV positive patients remain undiagnosed, and only a small part have active infection. 相似文献40.
Jesús Oliva Carmen Malo Ana Fernández Ana Izquierdo Henar Marcos Carlos Cevallos Jesús Castilla Rocio García Mercedes Díez 《Enfermedades infecciosas y microbiología clínica》2014