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1.
Artigo em Zh | MEDLINE | ID: mdl-37006146

RESUMO

Objective: To investigate the current situation of job involvement of nurses in military hospitals in Henan Province and analyze the influencing factors, so as to provide reference for improving the level of job involvement of military nurses. Methods: In February 2022, the employed nurses of 4 military hospitals in Henan Province were investigated by convenient sampling method. A total of 663 questionnaires were collected, including 632 valid questionnaires, with an effective recovery rate of 95.32%. The self-designed questionnaire was used to investigate the basic information of nurses, the Job Involvement Scale was used to investigate the job involvement of nurses, the Emotional Labor Scale for Nurses was used to investigate nurses' emotions, and the Work-Family Conflict Scale was used to investigate the work-family conflict of nurses. Independent sample t-test and univariate analysis of variance were used to compare the job involvement of military employed nurses with different demographic characteristics, Pearson correlation analysis was used to explore the correlation between emotional labor, work-family conflict and job involvement, and hierarchical regression analysis was used to explore the impact of relevant variables on the job involvement of military employed nurses. Results: The total average score of job involvement of military employed nurses was (3.68±1.13), and the scores of vitality, dedication and focus were (3.64±1.15), (3.74±1.25) and (3.67±1.21) respectively. The total score of emotional labor of nurses was 33-80 (62.95±8.12), with an average score of (3.93±0.51). The total score of work-family conflict was 18-94 (55.16±13.53), with an average score of (3.06±0.75). Professional emotional regulation, patient-centered emotional inhibition and standardized emotional play were positively related to the job involvement (r=0.46, 0.41, 0.22, P<0.01). Time-based conflict, stress-based conflict and behavior-based conflict had negative correlation with the job involvement (r=-0.12, -0.23, -0.20, P<0.01). In hierarchical regression analysis, after controlling demographic variables, emotional labor and work-family conflict accounted for 17.2% and 4.2% of the variation of job involvement. Conclusion: The job involvement of military employed nurses tends to be at a moderate level. Emotional labor and work-family conflict can significantly affect their job involvement.


Assuntos
Hospitais Militares , Enfermeiras e Enfermeiros , Estados Unidos , Humanos , Conflito Familiar , Inquéritos e Questionários , Análise de Regressão , Satisfação no Emprego
2.
Trop Anim Health Prod ; 50(8): 1893-1901, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30008131

RESUMO

This study was conducted to investigate the effects of heat stress on the behavioral and physiological patterns in Small-tail Han sheep housed indoors in summer without climate control. Sixteen adult animals were allocated into two groups of eight animals, based on sex: one group of eight rams and one group of eight ewes. Temperature-humidity index (THI) was used to assess the degree of heat stress. All sheep were subjected to a 10-day pre-experimental period of habituation to the experimental feed and environment. Physiological parameters monitored were respiratory rate (RR), rectal temperature (RT), and heart rate (HR). Blood chemistry parameters were also recorded, including plasma minerals and blood metabolites, from jugular vein blood samples. Behavioral parameters were lying, standing, excreting, drinking, foraging, walking, and ruminating. The research findings showed that there were some significant differences of behavior (standing, P = 0.001; walking, P = 0.049; ruminating, P = 0.010), physiology (RR, P = 0.0001; HR, P = 0.002; RT, P = 0.03;) and plasma minerals and blood metabolites (sodium, P = 0.047; phosphorus, P = 0.002; T4, P = 0.041; cortisol, P = 0.0047; triglyceride, P = 0.009) between ram and ewe and that heat stress also significantly affected (P < 0.05) standing, lying, foraging and drinking behavior, all of the physiological parameters and some of the blood chemistry parameters (chlorides, sodium, phosphorus, total protein, tetraiodothyronine, cholesterol, triglyceride, creatinine, cortisol, and glucose). These results indicate that ewe has better high-temperature tolerance than ram, and heat stress can alter behavioral and physiological patterns in Small-tail Han sheep housed indoors. These changes may allow the sheep to adapt better to the ambient temperature.


Assuntos
Comportamento Animal , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico/fisiologia , Carneiro Doméstico/fisiologia , Animais , Temperatura Corporal , Colesterol/sangue , Ingestão de Líquidos , Ingestão de Alimentos , Feminino , Frequência Cardíaca , Transtornos de Estresse por Calor/fisiopatologia , Transtornos de Estresse por Calor/psicologia , Temperatura Alta , Abrigo para Animais , Umidade , Hidrocortisona/sangue , Masculino , Taxa Respiratória , Estações do Ano , Ovinos , Estresse Fisiológico , Temperatura , Triglicerídeos/sangue
3.
Genet Mol Res ; 13(3): 5446-51, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-25078601

RESUMO

We conducted a hospital-based case-control study to investigate the associations of dietary intake of folate and MTHFR C677T and A1298C polymorphisms with breast cancer in a Chinese population. A 1:1-matched case-control study was conducted. Two hundred and thirty patients who were newly diagnosed and histologically confirmed breast cancer and 230 controls were enrolled from Xinxiang Central Hospital. Folate intake was calculated by standard portion size and relative size for each food item in the questionnaire. Genotyping of MTHFR C677T and A1298C was performed by PCR-RFLP. MTHFR 677TT (OR = 2.26, 95%CI = 1.09-4.87, P = 0.02) and T allele (OR = 1.40, 95%CI = 1.03-1.90, P = 0.03) had an increased risk of laryngeal cancer when compared with the CC genotype. We found any interaction between MTHFR C677T and folate intake (P for interaction = 0.02). In conclusion, our study demonstrated that MTHFR C677T polymorphism and folate are associated with risk of breast cancer.


Assuntos
Neoplasias da Mama/genética , Ácido Fólico/efeitos adversos , Genótipo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Adulto , Alelos , Povo Asiático , Neoplasias da Mama/etnologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Ingestão de Alimentos/fisiologia , Feminino , Ácido Fólico/administração & dosagem , Expressão Gênica , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
4.
Anim Genet ; 42(1): 83-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20477798

RESUMO

A number of studies have mapped QTL regulating porcine fatness and growth traits to the region of the major histocompatibility complex (MHC) on porcine chromosome 7 using various experimental crosses. The QTL results from crosses using the Chinese Meishan (MS) (slow growing and fat) are particularly interesting because the MS alleles have been found to be associated with increased growth rate and reduced backfat depth. We investigated these QTL further in a composite population derived previously over eight generations by intercrossing Meishan and the European Large White breeds. Genotype information from 32 markers in a 15cM target region was used in linkage and association analyses. A two-step variance component analysis identified QTL for three growth-related traits, explaining 19 ∼ 24% of the phenotypic variance with a confidence interval of 4 cM in the target region. SNP association analyses found that ss181128966 and ss181128924 within the QTL interval were strongly associated with the growth traits. Only weak signals for an effect on backfat depth were found in the association and linkage analyses, possibly because of past directional selection in the composite population.


Assuntos
Complexo Principal de Histocompatibilidade , Carne , Locos de Características Quantitativas , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/genética , Tecido Adiposo/crescimento & desenvolvimento , Animais , Cruzamento , Polimorfismo de Nucleotídeo Único , Característica Quantitativa Herdável
5.
Anim Genet ; 42(3): 293-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21054450

RESUMO

Good eggshell quality is important for both table egg quality and chicken reproductive performance. Weak eggshells cause economic losses in all production steps. Poor eggshell quality also poses increased risk for Salmonella infections. Eggshell quality has been a difficult trait to improve by traditional breeding, as it can be measured only for females and it is difficult and expensive to measure. Breeding for improved shell quality may therefore benefit from the use of marker-assisted selection. In an effort to find markers linked to eggshell quality, we have used an F(2) population of 668 females to map quantitative trait loci (QTL) affecting eggshell traits (eggshell deformation, breaking force, weight). By using 160 microsatellite markers on 27 chromosomes, we found 11 genome-wide and 15 suggestive QTL for shell traits measured at different times during production. Loci affecting the deformation were found on chromosomes 1, 2, 6, 10, 14 and Z. Loci affecting the breaking force were detected on chromosomes 2, 3, 10, 12 and Z. Loci affecting the shell weight were detected on chromosomes 6, 12, 24 and Z. Each QTL explains between 1.5% and 4.6% of the phenotypic variance, adding up to 10-15% of total phenotypic variance explained for the different traits. No epistatic effects were observed between loci affecting eggshell traits. Because the effects for quality are mainly additive, these results provide a basis for further characterization of the loci to identify closely linked markers to be used in marker-assisted selection.


Assuntos
Galinhas/genética , Casca de Ovo , Ovos/análise , Locos de Características Quantitativas , Animais , Embrião de Galinha , Mapeamento Cromossômico , Feminino , Ligação Genética , Genoma , Genótipo , Repetições de Microssatélites , Fenótipo
6.
Anim Genet ; 42(1): 15-21, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20528845

RESUMO

High throughput analyses were performed to detect epistatic QTL in 17 body dimension and organ weight traits from a large F(2) pig population derived from a White Duroc and Erhualian intercross. The analyses used a nested test framework to handle multiple tests and a combined search algorithm to map epistatic QTL with empirical genome-wide thresholds derived via prior permutation. Alternative statistical models (e.g. including vs. excluding carcass weight as a covariate) were tested to develop an in-depth understanding of the role of epistasis in these kinds of traits. Epistasis signals were detected in only two or three traits under each statistical model studied. The interaction component of each pair of epistatic QTL explained a small proportion (0.7 to 2.1%) of the phenotypic variance in general. About half of the detected epistatic QTL pairs involved one of the two major QTL on porcine chromosomes 7 and 4. In those traits, the Erhualian allele consistently increased the phenotypes for the chromosome 7 QTL but decreased them for the chromosome 4 QTL. Models including carcass weight as covariate detected epistasis in body dimension traits whereas those excluding carcass weight found epistasis in organ weight traits. In addition, the epistasis results suggested that a QTL on chromosome 14 could be important for a number of organ weight traits. Using the high-throughput analysis tool to examine different statistical models was essential for the generation of a complete picture of epistasis in a whole category of traits.


Assuntos
Epistasia Genética , Carne , Locos de Características Quantitativas , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/genética , Animais , Peso Corporal/genética , Cruzamentos Genéticos , Feminino , Masculino , Modelos Estatísticos , Tamanho do Órgão/genética
7.
Heredity (Edinb) ; 104(4): 401-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19789566

RESUMO

This study addresses the poorly explored issue of the control of false positive rate (FPR) in the mapping of pair-wise epistatic quantitative trait loci (QTL). A nested test framework was developed to (1) allow pre-identified QTL to be used directly to detect epistasis in one-dimensional genome scans, (2) to detect novel epistatic QTL pairs in two-dimensional genome scans and (3) to derive genome-wide thresholds through permutation and handle multiple testing. We used large-scale simulations to evaluate the performance of both the one- and two-dimensional approaches in mapping different forms and levels of epistasis and to generate profiles of FPR, power and accuracy to inform epistasis mapping studies. We showed that the nested test framework and genome-wide thresholds were essential to control FPR at the 5% level. The one-dimensional approach was generally more powerful than the two-dimensional approach in detecting QTL-associated epistasis and identified nearly all epistatic pairs detected from the two-dimensional approach. However, only the two-dimensional approach could detect epistatic QTL with weak main effects. Combining the two approaches allowed effective mapping of different forms of epistasis, whereas using the nested test framework kept the FPR under control. This approach provides a good search engine for high-throughput epistasis analyses.


Assuntos
Mapeamento Cromossômico/métodos , Mapeamento Cromossômico/normas , Epistasia Genética/fisiologia , Locos de Características Quantitativas/genética , Algoritmos , Animais , Simulação por Computador , Epistasia Genética/genética , Reações Falso-Positivas , Feminino , Estudo de Associação Genômica Ampla/métodos , Estudo de Associação Genômica Ampla/normas , Humanos , Padrões de Herança/genética , Masculino , Modelos Genéticos
8.
Anim Genet ; 40(6): 952-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19466937

RESUMO

Genome scans were conducted on an F(2) resource population derived from intercross of the White Plymouth Rock with the Silkies Fowl to detect QTL affecting chicken body composition traits. The population was genotyped with 129 microsatellite markers and phenotyped for 12 body composition traits on 238 F(2) individuals from 15 full-sib families. In total, 21 genome-wide QTL were found to be responsible for 11 traits, including two newly studied traits of proventriculus weight and shank girth. Three QTL were genome-wide significant: at 499 cm on GGA1 (explained 3.6% of phenotypic variance, P < 0.01) and 51 cm on GGA5 (explained 3.3% of phenotypic variance, P < 0.05) for the shank & claw weight and 502 cm on GGA1 (explained 1.4% of phenotypic variance, P < 0.05) for wing weight. The QTL on GGA1 seemed to have pleiotropic effects, also affecting gizzard weight at 490 cm, shank girth at 489 cm and intestine length at 481 cm. It is suggested that further efforts be made to understand the possible pleiotropic effects of the QTL on GGA1 and that on GGA5 for two shank-related traits.


Assuntos
Composição Corporal , Galinhas/genética , Carne , Locos de Características Quantitativas , Animais , Galinhas/fisiologia , Cruzamentos Genéticos , Repetições de Microssatélites
9.
Sex Transm Infect ; 84(5): 350-1, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18305121

RESUMO

Detection of people with acute HIV infection (AHI) affords an important opportunity for early HIV treatment and prevention. HIV RNA reverse transcriptase-polymerase chain reaction (RT-PCR) testing with two-stage pooling scheme was used to detect the AHI in specimens collected from sexually transmitted disease (STD) clinic patients in Guangxi, China. A total of 246 HIV RNA tests were required to screen 11 395 samples negative for conventional enzyme immunoassay (EIA) and Western blot assays, and five AHI cases (0.04%, 95%CI 0.02% to 0.10%) with a high viral load (median of 265,677 copies per ml) were detected. The total expenditure for RT-PCR testing reflected an added cost of $2.9 per specimen screened and $6575 per additional case of AHI identified among the study population. This study supports the feasibility of pooled RNA testing in addition to detection of HIV infections among patients at STD clinics in China, but the cost effectiveness should be carefully considered.


Assuntos
Infecções por HIV/diagnóstico , Doença Aguda , Adulto , Assistência Ambulatorial/economia , China , Análise Custo-Benefício , Diagnóstico Precoce , Estudos de Viabilidade , Feminino , Infecções por HIV/economia , Humanos , Masculino , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/economia
10.
Int J STD AIDS ; 19(12): 838-42, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19050215

RESUMO

SUMMARY: Syphilis testing guidelines in China are usually based on symptomatic criteria, overlooking risk assessment and ultimately opportunities for disease detection and control. We used data from 10,695 sexually transmitted disease (STD) clinic patients in Guangxi, China, to assess the efficacy of a potential screening tool inquiring about behavioural and health risk factors in identifying the STD patients who should not be triaged for syphilis testing under current guidelines, but on the contrary receive such testing. Validity testing of the screening tool was performed and receiver-operating characteristic curves were plotted to determine an optimal total risk score cut-off for testing. About 40.9% of patients with positive toluidine red unheated serum test and Treponema pallidum particle agglutination test did not show hallmark signs of syphilis. The screening tool was more sensitive in detecting infection in non-triaged male versus female patients (highest sensitivity = 90% vs. 55%) and the cut-off score to warrant testing was lower in non-triaged female patients than in non-triaged male patients (cut-off = 1 vs. 2). Most of the cases were missed among female STD patients. In spite of selective testing based on behavioural and health indicators that improve case detection, cases were still missed. Our study supports universal testing for syphilis in the STD population.


Assuntos
Inquéritos Epidemiológicos , Programas de Rastreamento/métodos , Infecções Sexualmente Transmissíveis/prevenção & controle , Sorodiagnóstico da Sífilis , Sífilis/prevenção & controle , China , Estudos Transversais , Feminino , Humanos , Masculino , Assunção de Riscos , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Fatores Socioeconômicos , Sífilis/diagnóstico , Sífilis/epidemiologia , Sífilis/microbiologia , Treponema pallidum/isolamento & purificação
11.
Zhonghua Jie He He Hu Xi Za Zhi ; 17(5): 294-6, 319, 1994 Oct.
Artigo em Zh | MEDLINE | ID: mdl-7712572

RESUMO

A nested-primer gene amplification assay (NPGAA) was established by using two pairs of primers, an outside pair of primers and an inside pair of primers, sequences of which were from M. tuberculosis(Mtb) gro EL genes. The outside pair of primers should amplify a 576-bp piece of the Mtb gro EL gene that contains sites for the inside pair of primers, which should amplify a 344-bp piece. The results shows NPGAA'S detectable limitation was 1 organism/ml and no amplification products were produced from DNAs of other mycobacterium species tested in this study. For detecting Mtb, the entire NPGAA, from sample preparation to data analysis, can be completed within 6-8 hours. When identifying AFB cultures isolated from lesions of skin diseases, the same positive size patterns were obtained.


Assuntos
DNA Bacteriano/análise , Mycobacterium tuberculosis/genética , Técnicas de Amplificação de Ácido Nucleico , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos
12.
Clin Microbiol Infect ; 19(10): 975-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23231450

RESUMO

Treatment with effective antibiotics is one important strategy for syphilis control in China. This study aimed to evaluate the prevalence of azithromycin resistance to T. pallidum in China. A cross-sectional study was conducted among 391 patients with early syphilis recruited from STD clinics in eight cities during October 2008 and October 2011. The swabs were obtained from the moist lesions of the participating patients. A touchdown/nested PCR of the 23S ribosomal RNA (rRNA) gene was performed on DNA samples extracted from these specimens. The presence or absence of the A2058G point mutation, conferring resistance to azithromycin, was determined by restriction enzyme digestion analysis of the PCR amplicon by MboII. Two hundred and eleven patients with primary or secondary syphilis were found to have T. pallidum DNA in their moist lesions by PCR assays. The A2058G mutation was present in 91.9% (194/211, 95% CI, 87.2-95.1%) of these patients, with no significant differences noted between patients from the eastern part (93.8%), southern part (88.6%) and northern part (95.2%) of China (χ(2) = 2.303, p 0.316). Compared with patients who had not taken macrolides in previous years before study entry, the patients who had taken the antibiotics had a significantly higher prevalence of azithromycin resistance (97.0% vs. 62.5%), with an odds ratio of 19.65 (95% CI, 5.77-66.93). It can be concluded that prevalence of azithromycin resistance is substantial in China and consequently that the macrolides should not be used as a treatment option for early or incubating syphilis in China.


Assuntos
Azitromicina/farmacologia , Sífilis/epidemiologia , Sífilis/microbiologia , Treponema pallidum/efeitos dos fármacos , Adulto , Antibacterianos/farmacologia , China/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana , Humanos , Masculino , Prevalência , Treponema pallidum/isolamento & purificação
14.
Anim Genet ; 38(3): 222-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17459018

RESUMO

Ear size and erectness are important conformation measurements in pigs. An F(2) population established by crossing European Large White (small, erect ears) with Chinese Meishan (large, flop ears) was used to study the genetic influence of the two ear traits for the first time. A linkage map incorporating 152 markers on 18 autosomal chromosomes was utilised in a genome scan for QTL. Significant QTL were found on SSC1, 5, 7, 9 and 12 for the two traits. The QTL on SSC5 and SSC7 had major effects and were significant at the genome-wide level (P < 0.01). The QTL on SSC1 for ear erectness also had a major effect and was genome-wide significant (P < 0.01). The 95% confidence interval (CI) of the ear size QTL on SSC5 spanned only 4 cM. The QTL on SSC7 for the two ear traits each had a CI of <20 cM, and their positions overlapped with those of the major QTL affecting subcutaneous fat depths on the same chromosome. This study provides insights on the complex genetic influences underlying pig ear traits and will facilitate positional candidate gene analysis to identify causative DNA variants.


Assuntos
Orelha/anatomia & histologia , Locos de Características Quantitativas , Sus scrofa/genética , Animais , Mapeamento Cromossômico , Cruzamentos Genéticos , Orelha/fisiologia , Genômica/métodos , Tamanho do Órgão
15.
Sex Transm Infect ; 82 Suppl 5: v33-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17121763

RESUMO

OBJECTIVES: To determine the performance of a rapid Chlamydia trachomatis (CT) test (Clearview Chlamydia MF) compared to the current "gold standard" (Roche Amplicor CT assay) test, and to assess acceptability of the tests to patients. METHODS: A total of 1497 women at sexually transmitted diseases (STD) clinics or re-education centres in six urban cities (Shanghai, Nanjing, Shenzhen, Guangzhou, Chengdu and Fuzhou) in China participated in the study. Three vaginal and three cervical swabs were collected from each participant. Rapid CT tests were performed locally on the first vaginal and cervical swabs and the results were read independently by two staff members. The second and third swabs were randomised for performing the Roche CT assay at the National STD Reference Laboratory. Acceptability of the rapid tests to patients was determined by asking patients in clinics about their willingness to wait for the results. RESULTS: The prevalence of CT was 13.2% (197/1497), as determined by the Roche assay with cervical specimens. CT was detected in 78 vaginal and 127 cervical specimens by the rapid test and the positive rates determined with cervical specimens were significantly higher than those with vaginal specimens (p<0.001). There was good agreement between the results read by two independent staff for either vaginal or cervical specimens (both kappa = 0.98, p<0.001). Sensitivities for vaginal and cervical specimens were 32.8% and 49.7%, respectively, and specificities were 99.2% and 97.9%, respectively. The positive predictive value was 85.7% for vaginal and 78.4% for cervical specimens. The vast majority of the patients (99.1%) were willing to wait up to two hours for the results. CONCLUSION: Clearview Chlamydia MF, while yielding a rapid result and requiring minimal laboratory facilities, had unacceptably low sensitivity compared to a nucleic acid amplification test. Rapid tests yielding results within one hour are generally accepted by the clients.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito/normas , Adulto , Colo do Útero/microbiologia , China , Feminino , Humanos , Masculino , Satisfação do Paciente , Fatores de Risco , Vagina/microbiologia
16.
Biometrics ; 56(4): 991-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11129496

RESUMO

Influence measures based on the pairwise deletion approach and the differentiation approach are developed for unmasking observations masked by other observations in the proportional hazards model. These influential observations might have substantial impact on statistical inference and might provide important information for model adequacy. One numerical example based on real data is presented and discussed.


Assuntos
Biometria/métodos , Modelos de Riscos Proporcionais , Probabilidade , Análise de Regressão , Reprodutibilidade dos Testes
17.
Biometrics ; 55(4): 1295-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11315087

RESUMO

Deletion diagnostics are developed for identifying observations that influence the estimates of regression parameters and the mixture parameter in the families of relative risk functions for failure time data. The diagnostic for the regression parameters is a generalization of Cain and Lange's (1984, Biometrics 40, 493-499) measure of individual influence. The generalizations of martingale residuals, Schoenfeld's partial residuals (1982, Biometrika 69, 239-241), and score residuals by Therneau, Grambsch, and Fleming (1990, Biometrika 77, 147-160) are also obtained. The influence of some observations on regression parameters can be drastically modified as the mixture parameter changes, even for a very small change. In addition, adding or deleting some observations might result in choosing different models. The diagnostics are applied to a family proposed by Guerrero and Johnson (1982, Biometrika 69, 309-314). One illustrative example is presented.


Assuntos
Biometria , Modelos Estatísticos , Análise de Sobrevida , Humanos , Funções Verossimilhança , Modelos de Riscos Proporcionais , Análise de Regressão , Risco
18.
Stat Med ; 15(5): 449-62, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8668871

RESUMO

We develop a statistical model for estimating cystic fibrosis (CF) incidence among infants born in the U.S.A. that accounts for under-diagnosis due to death prior to diagnosis and we apply it to the Cystic Fibrosis Foundation Patient Registry data for the years 1989 to 1991. The resulting estimate of incidence relative to live births among whites is 1:3419 while that among non-whites is 1:12,163. As a by-product of the modelling approach, estimates of the underlying average diagnosis age given survival to diagnosis are 4.09 years for whites and 4.55 years for non-whites, but this difference was not statistically significant and appears to demonstrate that diagnosis efforts may be approximately the same for whites and non-whites. Also, as another by-product of the modelling approach, CF mortality was estimated as more severe for females than males and marginally more severe for non-whites than whites. A variety of statistical methods underlie achievement of these results, including semi-parametric maximum likelihood, survival analysis, multiple imputation and bootstrap techniques.


Assuntos
Fibrose Cística/epidemiologia , Modelos Estatísticos , Análise Atuarial , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Intervalos de Confiança , Fibrose Cística/mortalidade , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Análise de Sobrevida , Estados Unidos/epidemiologia
19.
Int J Lepr Other Mycobact Dis ; 58(2): 328-33, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2198316

RESUMO

In this study, we have developed two latex agglutination tests (LATs) with phenolic glycolipid-I (PGL-I) and natural disaccharide-octyl-bovine serum albumin (ND-O-BSA) as antigens in 110 leprosy patients (LL = 30, BL = 30, BT = 30, and TT = 20), 50 tuberculosis cases, and 30 normal controls. These two LATs were compared with corresponding ELISAs (ND-O-BSA ELISA and PGL-I ELISA) and analyzed by the chi-squared test. There were no significant differences between the two LATs (PGL-I LAT and ND-O-BSA LAT) and their corresponding ELISAs. There was an increase in the proportion of positive cases detectable which coincided with the clinical classification of leprosy, i.e., lepromatous cases were more likely to be positive than tuberculoid cases. LATs are more simple and rapid than ELISAs and have high sensitivity (77% in ND-O-BSA LAT, 80.5% in PGL-I LAT) and specificity (99% in both LATs). LATs may become useful tools for the immunodiagnosis of leprosy in the field. The stability and repeatability of LATs are discussed in detail.


Assuntos
Anticorpos Antibacterianos/análise , Testes de Fixação do Látex , Hanseníase/diagnóstico , Mycobacterium leprae/imunologia , Antígenos de Bactérias/imunologia , Distribuição de Qui-Quadrado , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Glicolipídeos/imunologia , Humanos , Soros Imunes/imunologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Soroalbumina Bovina/imunologia
20.
J Tongji Med Univ ; 12(3): 154-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1360546

RESUMO

In this experiment, we used morgrel dogs to study the effect of trauma on the neuro-endocrine and metabolic organs and the effects of hormones on metabolism by determining the levels of intracellular cAMP, cGMP and DNA. From the changes in intracellular nucleotides, we learned that many neuro-endocrine organs and the main metabolic organs are characteristic of predominance in alpha-adrenoreceptor after trauma, thereby leading to high blood sugar.


Assuntos
AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , DNA/metabolismo , Fraturas Ósseas/metabolismo , Animais , Contusões/metabolismo , Cães , Feminino , Fíbula/lesões , Masculino , Ossos do Metatarso/lesões , Neurotransmissores/metabolismo , Fraturas da Tíbia/metabolismo
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