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1.
J Dairy Sci ; 97(7): 4568-78, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24792796

RESUMEN

Pasture-based dairy producers in the United States face costs, revenue streams, and management challenges that may differ from those associated with confinement dairy production systems. Three Grazing Merit indices (GM$1, GM$2, and GM$3), parallel to the US Lifetime Net Merit (NM$) index, were constructed using economic values appropriate for grazing production in the United States. Milk prices based on averages from the previous 5 yr were used for GM$1, whereas GM$2 and GM$3 used milk prices found in NM$. Cull prices and interest rates from NM$ were used in GM$3 but were updated for GM$1 and GM$2. All other inputs remained constant among GM$1, GM$2, and GM$3. Economic costs and revenues were obtained from surveys, recent literature, and farm financial record summaries. Derived weights for GM$ were then multiplied by the predicted transmitting abilities of 584 active artificial insemination Holstein bulls to compare with NM$. Spearman rank correlations for NM$ were 0.93 with GM$1, 0.98 with GM$2, and 0.98 with GM$3. Traits (and their percentages of weight) comprising GM$1, GM$2, and GM$3, respectively, included milk volume (24, 0, 0%), Fat yield (16, 21, 21%), protein yield (4, 17, 17%), productive life (7, 8, 7%), somatic cell count (-8, -9, -9%), feet and legs composite (4, 4, 4%), body size composite (-3, -4, -4%), udder composite (7, 8, 8%), daughter pregnancy rate (18, 20, 20%), calving ability (3, 3, 3%), and dairy form (6, 6, 6%). These weights compared with NM$ weights of 0, 19, 16, 22, 10, 4, 6, 7, 11, 5, and 0% for the same traits, respectively. Dairy form was added to GM$ to offset the decrease in strength associated with selection to reduce stature through selection against body size. Emphasis on productive life decreased in GM$ because grazing cattle are estimated to remain in the herd considerably longer, diminishing the marginal value of productive life. Although NM$ provides guidance for grazing dairy producers, a GM$ index based upon appropriate costs and revenues allows for selection of cows and bulls for more optimal genetic progress.


Asunto(s)
Cruzamiento , Bovinos/fisiología , Industria Lechera/métodos , Animales , Bovinos/genética , Industria Lechera/economía , Femenino , Masculino , Modelos Económicos , Embarazo , Estados Unidos
2.
J Clin Microbiol ; 44(9): 3361-5, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16954273

RESUMEN

Three hundred sixty-one quinupristin-dalfopristin (Q-D)-resistant Enterococcus faecium (QDREF) isolates were isolated from humans, turkeys, chickens, swine, dairy and beef cattle from farms, chicken carcasses, and ground pork from grocery stores in the United States from 1995 to 2003. These isolates were evaluated by pulsed-field gel electrophoresis (PFGE) to determine possible commonality between QDREF isolates from human and animal sources. PCR was performed to detect the streptogramin resistance genes vatD, vatE, and vgbA and the macrolide resistance gene ermB to determine the genetic mechanism of resistance in these isolates. QDREF from humans did not have PFGE patterns similar to those from animal sources. vatE was found in 35%, 26%, and 2% of QDREF isolates from turkeys, chickens, and humans, respectively, and was not found in QDREF isolates from other sources. ermB was commonly found in QDREF isolates from all sources. Known streptogramin resistance genes were absent in the majority of isolates, suggesting the presence of other, as-yet-undetermined, mechanisms of Q-D resistance.


Asunto(s)
Animales Domésticos/microbiología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Grampositivas/microbiología , Carne/microbiología , Virginiamicina/farmacología , Animales , Proteínas Bacterianas/genética , Bovinos/microbiología , Pollos/microbiología , Electroforesis en Gel de Campo Pulsado , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Humanos , Pavos/microbiología , Estados Unidos
3.
J Clin Microbiol ; 41(3): 1109-13, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12624037

RESUMEN

We evaluated the molecular mechanism for resistance of 360 enterococci for which the gentamicin MICs were >/=128 micro g/ml. The aac(6')-Ie-aph(2")-Ia, aph(2")-Ic, and aph(2")-Id genes were identified by PCR in isolates from animals, food, and humans. The aph(2")-Ib gene was not identified in any of the isolates. Two Enterococcus faecalis isolates (MICs > 1,024 micro g/ml) from animals failed to generate a PCR product for any of the genes tested and likely contain a new unidentified aminoglycoside resistance gene. Pulsed-field gel electrophoresis (PFGE) analysis showed a diversity of strains. However, 1 human and 18 pork E. faecalis isolates from Michigan with the aac(6')-Ie-aph(2")-Ia gene had related PFGE patterns and 2 E. faecalis isolates from Oregon (1 human and 1 grocery store chicken isolate) had indistinguishable PFGE patterns. We found that when a gentamicin-resistant gene was present in resistant enterococci from animals, that gene was also present in enterococci isolated from food products of the same animal species. Although these data indicate much diversity among gentamicin-resistant enterococci, the data also suggest similarities in gentamicin resistance among enterococci isolated from humans, retail food, and farm animals from geographically diverse areas and provide evidence of the spread of gentamicin-resistant enterococci from animals to humans through the food supply.


Asunto(s)
Enfermedades de los Animales/transmisión , Enterococcus/efectos de los fármacos , Microbiología de Alimentos , Gentamicinas/farmacología , Infecciones por Bacterias Grampositivas/transmisión , Animales , Animales Domésticos/microbiología , Farmacorresistencia Bacteriana , Enterococcus/patogenicidad , Heces/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Humanos , Pruebas de Sensibilidad Microbiana , Estados Unidos
4.
JAMA ; 286(15): 1857-62, 2001 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-11597287

RESUMEN

CONTEXT: Macrolide antibiotics, including erythromycin, clarithromycin, and azithromycin, are the mainstays of empirical pneumonia therapy. Macrolide resistance among Streptococcus pneumoniae, the most common cause of community-acquired pneumonia, is increasing in the United States. Whether resistance is a significant problem or whether macrolides remain useful for treatment of most resistant strains is unknown. OBJECTIVE: To examine the epidemiology of macrolide-resistant pneumococci in the United States. DESIGN AND SETTING: Analysis of 15 481 invasive isolates from 1995 to 1999 collected by the Centers for Disease Control and Prevention's Active Bacterial Core surveillance system in 8 states. MAIN OUTCOME MEASURES: Trends in macrolide use (1993-1999) and resistance and factors associated with resistance, including examination of 2 subtypes, the M phenotype, associated with moderate minimum inhibitory concentrations (MICs), and the MLS(B) phenotype, associated with high MICs and clindamycin resistance. RESULTS: From 1993 to 1999, macrolide use increased 13%; macrolide use increased 320% among children younger than 5 years. Macrolide resistance increased from 10.6% in 1995 to 20.4% in 1999. M phenotype isolates increased from 7.4% to 16.5% (P<.001), while the proportion with the MLS(B) phenotype was stable (3%-4%). The median erythromycin MIC (MIC(50)) of M phenotype isolates increased from 4 microg/mL to 8 microg/mL. In 1999, M phenotype strains were more often from children than persons 5 years or older (25.2% vs 12.6%; P<.001) and from whites than blacks (19.3% vs 11.2%; P<.001). CONCLUSIONS: In the setting of increasing macrolide use, pneumococcal resistance has become common. Most resistant strains have MICs in the range in which treatment failures have been reported. Further study and surveillance are critical to understanding the clinical implications of our findings.


Asunto(s)
Antibacterianos/farmacología , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/efectos de los fármacos , Adolescente , Adulto , Antibacterianos/uso terapéutico , Niño , Preescolar , Farmacorresistencia Microbiana , Utilización de Medicamentos/estadística & datos numéricos , Humanos , Lactante , Modelos Logísticos , Macrólidos , Pruebas de Sensibilidad Microbiana , Análisis Multivariante , Fenotipo , Infecciones Neumocócicas/epidemiología , Serotipificación , Streptococcus pneumoniae/clasificación , Estados Unidos/epidemiología
5.
Infect Control Hosp Epidemiol ; 22(6): 352-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11519912

RESUMEN

OBJECTIVE: To estimate the extent of, and evaluate risk factors for, elevated carboxyhemoglobin levels among patients undergoing general anesthesia and to identify the source of carbon monoxide. DESIGN: Matched case-control study to measure carboxyhemoglobin levels. SETTING: Large academic medical center. PARTICIPANTS: 45 surgical patients who underwent general anesthesia RESULTS: Case-patients were more likely than controls to undergo surgery on Monday or Tuesday (10/15 vs 7/30; matched odds ratio [mOR], 7.7; 95% confidence interval [CI95], 1.8-34; P=.01), in one particular room (7/15 vs 4/30; mOR, 8.5; CI95, 1.5-48; P=.03) or in a room that was idle for > or =24 hours (11/15 vs 1/30; mOR, 95.5; CI95, 8.0-1,138; P< or =.001). In a multivariate model, only rooms, and hence the anesthesia equipment, that were idle for > or =24 hours were independently associated with elevated intraoperative carboxyhemoglobin levels (OR, 22.4; CI95, 1.5-338; P=.025). Moreover, peak carboxyhemoglobin levels were correlated with the length of time that the room was idle (r=0.7; CI95, 0.3-0.9). Carbon monoxide was detected in the anesthesia machine outflow during one case-procedure. No contamination of anesthesia gas supplies or CO2 absorbents was found. CONCLUSIONS: Carbon monoxide may accumulate in anesthesia circuits left idle for > or =24 hours as a result of a chemical interaction between CO2-absorbent granules and anesthetic gases. Patients administered anesthesia through such circuits may be at increased risk for elevated carboxyhemoglobin levels during surgery or the early postoperative period.


Asunto(s)
Anestesia General/efectos adversos , Intoxicación por Monóxido de Carbono/etiología , Adulto , Anciano , Anestesia General/instrumentación , Dióxido de Carbono/metabolismo , Carboxihemoglobina/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Exposición por Inhalación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Procedimientos Quirúrgicos Operativos
6.
J Infect Dis ; 184(1): 56-65, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11398110

RESUMEN

Macrolide resistance associated with macrolide efflux (mef) has rapidly increased in Streptococcus pneumoniae. We defined the genetic structure and dissemination of a novel mefE-containing chromosomal insertion element. The mefE gene was found on the 5' end of a 5.5- or 5.4-kb insertion designated as the macrolide efflux genetic assembly (mega), which is found in > or =4 distinct sites of the pneumococcal genome. The element was transformable and conferred macrolide resistance to susceptible S. pneumoniae. The first 2 open-reading frames (ORFs) of the element formed an operon composed of mefE and a predicted adenosine triphosphate-binding cassette homologous to msrA. Convergent to this efflux operon were 3 ORFs with homology to stress response genes of Tn5252. Mega was related to the recently described mefA-containing element Tn1207.1 but lacked the genes necessary for transposition and had unique termini and insertion sites. In metropolitan Atlanta, macrolide resistance due to mega rapidly increased in S. pneumoniae by clonal expansion and horizontally by transformation.


Asunto(s)
Proteínas Bacterianas/genética , Cromosomas Bacterianos , Proteínas de Transporte de Membrana , Mutagénesis Insercional , Conformación de Ácido Nucleico , Streptococcus pneumoniae/genética , Secuencia de Aminoácidos , Electroforesis en Gel de Campo Pulsado , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Operón , Alineación de Secuencia
7.
J Infect Dis ; 182(5): 1417-24, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11023465

RESUMEN

From 1994 through 1999, the available isolates (4148 isolates) from active population-based surveillance of invasive pneumococcal disease in metropolitan Atlanta were serotyped and were tested for antimicrobial susceptibility. Macrolide-resistant isolates were studied for the presence of ermAM (a ribosomal methylase gene), mefE (a macrolide efflux gene), and tetM (the class M tetracycline resistance gene). Macrolide resistance increased from 16% of all invasive isolates in 1994 to 32% in 1999. Of the macrolide-resistant pneumococcal isolates studied, 99% contained genomic copies of mefE or ermAM. Isolates with ermAM were mainly serotypes 6B, 23F, 14, or 19F and contained tetM; mefE-associated isolates were predominantly serotypes 14, 6A, or 19F, and most did not contain tetM. The frequency of the ermAM-mediated phenotype in invasive Streptococcus pneumoniae remained stable over the 6-year surveillance. However, the mefE-mediated phenotype increased from 9% in 1994 to 26% of all isolates in 1999 and was noted in new serotypes. By 1999, 93% of the mefE-containing strains had minimum inhibitory concentrations >/=8 microgram/mL. Dissemination of the mefE determinant accounted for the rapid increase in the rate of macrolide resistance in our S. pneumoniae population.


Asunto(s)
Antibacterianos/farmacología , Eritromicina/farmacología , Streptococcus pneumoniae/efectos de los fármacos , Farmacorresistencia Microbiana , Pruebas de Sensibilidad Microbiana , Streptococcus pneumoniae/genética , Factores de Tiempo
8.
Matern Child Health J ; 2(1): 45-54, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10728258

RESUMEN

OBJECTIVES: Since dramatically shortened newborn hospitalization has shifted the focus of care from the hospital, a central policy question has become how to assure a system of care that extends into the home and community. The objective of this study was to examine the role of the state Maternal and Child Health Title V programs in the assessment of the issue of newborn discharge, the development of policies, and the assurance of appropriate care. METHOD: The director or their designee in all 50 states and the District of Columbia participated in a structured telephone interview lasting 30-60 minutes. RESULTS: Twenty-eight states reported new or previously implemented mandates for 48 hours of private insurance coverage for postpartum hospitalization. Only 6 states reported mandates concerning private insurance coverage of inpatient services, but 20 states reported mandates for postdischarge services. In the assessment function, only 18 maternal and child health (MCH) programs reported that they had undertaken specific studies on the effects of discharge timing in their states. In policy development, 18 of the 51 respondents reported that the MCH program initiated newborn discharge discussions, 23 reported that the agency participated in discussions, and 10 indicated that they did not participate. In assurance, 29 programs reported that they had taken action to provide technical assistance to local communities in developing follow-up systems. The relationship between the performance of core functions and the development of specific discharge policies in the state was minimal. CONCLUSIONS: The MCH programs appear to have played varied, but often limited, roles in the development of discharge policies. It is essential for MCH programs to engage actively in the policy-making process. But in the political environment surrounding newborn discharge policy, where laws and regulations consistent with the well-being of infants and mothers were being enacted, the limited MCH program roles may have been appropriate. Arguing against this conclusion, however, is that only 15 programs believed they had been effective and only 19 were satisfied with the discharge policies in their states, which suggests that a more proactive role may be necessary.


Asunto(s)
Servicios de Salud del Niño/organización & administración , Recién Nacido , Servicios de Salud Materna/organización & administración , Alta del Paciente , Planes Estatales de Salud , Cuidados Posteriores , Política de Salud , Humanos , Tiempo de Internación , North Carolina , Estados Unidos
9.
Pediatr Infect Dis J ; 15(8): 650-4, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8858666

RESUMEN

BACKGROUND: A safe and effective parainfluenza type 3 (PIV-3) virus vaccine is needed to prevent serious PIV-3-associated illness in infants younger than 6 months of age. In previous studies a live bovine PIV-3 (BPIV-3) vaccine, which was developed to prevent human PIV-3 (HPIV-3) disease, was shown to be safe, infectious, immunogenic and phenotypically stable in 6- to 36-month-old infants and children. METHODS: The safety, infectivity and immunogenicity of a single dose of the BPIV-3 vaccine was evaluated in a randomized, placebo-controlled, double blinded trial in 19 infants 2 to 5.9 months of age and in 11 additional 6- to 36-month-old subjects. RESULTS: The BPIV-3 vaccine was well-tolerated in both age groups and infected 92% of those younger than 6 months and 89% of those older than 6 months of age. Serum hemagglutination-inhibition (HAI) antibody responses to HPIV-3 and to BPIV-3, respectively, were detected in 42 and 67% of the younger infants, compared with 70 and 85% of the older subjects. In the younger infants we analyzed the rate of antibody response by titer of maternally acquired antibodies; low titer was defined as a preimmunization serum HAI titer < 1:8 and high titer was defined as a preimmunization serum HAI titer > or = 1:8. Young infants with a low titer of maternally acquired antibodies were significantly more likely to respond to the BPIV-3 vaccine that those with a high titer (89% vs. none for serum HAI response to BPIV-3; P = 0.02, Fisher's exact test). CONCLUSIONS: This study demonstrated that the BPIV-3 vaccine was safe and infectious in infants younger than 6 months of age and was also immunogenic in the majority of these young infants. Additional studies are needed to determine whether two or more doses will enhance the immunogenicity of the BPIV-3 vaccine in young infants and to assess its safety and immunogenicity when given simultaneously with routine childhood immunizations.


Asunto(s)
Infecciones del Sistema Respiratorio/prevención & control , Infecciones por Respirovirus/prevención & control , Respirovirus/inmunología , Vacunas Virales , Anticuerpos Antivirales/biosíntesis , Preescolar , Método Doble Ciego , Técnica del Anticuerpo Fluorescente Indirecta , Pruebas de Inhibición de Hemaglutinación , Humanos , Lactante , Infecciones del Sistema Respiratorio/virología , Respirovirus/aislamiento & purificación , Infecciones por Respirovirus/fisiopatología , Vacunación
10.
AIDS Educ Prev ; 7(2): 134-44, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7542465

RESUMEN

Video education is the most popular and effective medium for informing the adolescent population. This study investigated the impact of a culturally relevant HIV/AIDS video education. One hundred and ninety-four African-American teenagers were assigned to either a culturally sensitive or culturally dissimilar video education intervention. Results indicate that both interventions were effective in increasing AIDS knowledge scores. An interaction effect was found between levels of perceived AIDS risk knowledge and participation in the culturally sensitive intervention (CSV). Only the CSV intervention was effective with adolescents who claimed to "know a lot" about AIDS (e.g., "Know-It-All" subgroup). Students in both conditions who were worried about getting AIDS demonstrated higher AIDS risk knowledge at post-assessment. This study provides further evidence of within-ethnicity diversity among African-American youth and for developing culture- and subgroup-specific HIV/AIDS education.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/prevención & control , Actitud Frente a la Salud , Negro o Afroamericano/psicología , Características Culturales , Educación en Salud/métodos , Síndrome de Inmunodeficiencia Adquirida/psicología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Adolescente , Recursos Audiovisuales , Femenino , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Factores de Riesgo
11.
Chirurg ; 62(6): 462-6, 1991 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-1914643

RESUMEN

60 patients with symptomatic gallstone disease were asked about their abdominal symptoms and food intolerance. Equally a healthy control group was investigated. Preoperatively, 72% of patients with gallstones suffered from right upper quadrant pain. Additionally all patients complained of associated dyspeptic symptoms (100% vs. 8% of the control group). 51% of patients with gallstone disease vs. 15% of the control group avoided flatulent and fatty food. 4 months after cholecystectomy, 90% were painfree, 82% were free of dyspeptic symptoms and 84% were not complaining of any food intolerance. 6% developed new food intolerances. Thus cholecystectomy seems to be an effective treatment, not only for typical gallstone related symptoms, but also for associated symptoms, such as dyspepsia and food intolerance. Different therapeutic regimens have to compete with these results.


Asunto(s)
Colecistectomía , Colelitiasis/complicaciones , Dispepsia/etiología , Hipersensibilidad a los Alimentos/etiología , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Colelitiasis/cirugía , Conducta Alimentaria , Femenino , Estudios de Seguimiento , Cálculos Biliares/complicaciones , Cálculos Biliares/cirugía , Humanos , Masculino , Persona de Mediana Edad
13.
Can Fam Physician ; 36: 2183-6, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20469510

RESUMEN

To assess the involvement of family physicians in the continuing care of cancer patients, 499 patients attending the London Regional Cancer Centre for follow-up appointments were questioned. Of the 493 patients with a family doctor, 282 (57.2%) reported that their family doctor had been involved in the diagnosis, 132 (26.8%) in the treatment, and 214 (43.4%) in the follow up. Only 60% thought that their family doctor was aware of their current problems, and only 31.4% had an appointment to see their family doctor in the near future.

14.
Anal Biochem ; 178(1): 184-93, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2471419

RESUMEN

Simplified and expedient methodologies for examination of cellular gene expression at the mRNA and protein levels, utilizing in situ hybridization and peroxidase-anti-peroxidase immunodetection, were developed. These techniques were first optimized for the detection of extracellular matrix genes expressed by cultured human skin fibroblasts and keratinocytes, the two principal cell types of human skin. In situ hybridizations and Northern transfer analyses with human-sequence-specific cDNAs encoding collagenous and noncollagenous protein sequences demonstrated selective expression of different matrix genes by these two cell types, indicating different biosynthetic capacities of these cells and attesting to the specificity of the hybridizations. The utility of in situ hybridization was also demonstrated in mixed primary cell cultures established from cutaneous neurofibromas consisting of Schwann cells, perineurial cells, and fibroblasts. The methodologies developed here were further utilized for simultaneous detection of fibronectin mRNA and immunoreactive protein in fibroblast cultures. This procedure allowed detection of grains representative of radioactively labeled cDNA-mRNA hybrids and protein epitopes, as visualized by peroxidase-anti-peroxidase immunodetection on the same cells. This methodology, with appropriate modifications, may be applicable to other cell types as well as tissue specimens.


Asunto(s)
Células Epidérmicas , Epítopos/análisis , Matriz Extracelular/análisis , ARN Mensajero/análisis , Células Cultivadas , Sondas de ADN , Fibroblastos/análisis , Fibronectinas/análisis , Regulación de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Queratinas/genética , Laminina/análisis , Hibridación de Ácido Nucleico , Procolágeno/análisis
15.
Biochemistry ; 27(24): 8870-8, 1988 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-3242614

RESUMEN

Interactions of meso-tetrakis(4-N-methylpyridiniumyl)porphyrin [TMpyP(4)] with poly[d(G-C)].poly[d(G-C)] [poly[d(G-C)2] and poly[d(A-T)].poly[d(A-T)] [poly[d(A-T)2] were studied by equilibrium dialysis and stopped-flow dissociation kinetics as a function of [Na+]. Metalloderivatives of TMpyP(4), NiTMpyP(4), and ZnTMpyP(4) were also investigated. The apparent equilibrium binding constants (Kobs) were approximately the same for TMpyP(4) binding to either poly[d(G-C)2] or poly[d(A-T)2] and decreased with increasing [Na+]. The slopes of the plots of log Kobs vs log [Na+] were similar, with values close to -2.7. Contrary to implications in previously reported studies, these data do not indicate that TMpyP(4) prefers to bind to GC sites at low ionic strength and to AT sites at high ionic strength. In contrast, binding of ZnTMpyP(4) to these two polymers is very different. Comparisons of Kobs values at 0.065 M [Na+] indicate that ZnTMpyP(4) binding to AT sites is approximately 200 times more favorable than binding to GC sites, a finding in agreement with previous qualitative observations. Although the binding of the Zn species to the GC polymer was too weak for us to assess the salt effect, the plot of log Kobs vs log [Na+] gave a slope of -2.0 for ZnTMpyP(4) binding to poly[d(A-T)2]. Application of condensation theory for polyelectrolytes suggests similar charge interactions for ZnTMpyP(4) and for TMpyP(4) binding to poly[d(A-T)2]. Likewise, the rates of dissociation from poly[d(A-T)2] were similar for TMpyP(4) and ZnTMpyP(4) [and also NiTMpyP(4)]. However, whereas TMpyP(4) [and NiTMpyP(4)] dissociation from poly[d(G-C)2] was measurable, that for ZnTMpyP(4) was too fast to measure.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
ADN , Mesoporfirinas , Metaloporfirinas , Polidesoxirribonucleótidos , Porfirinas , Fenómenos Químicos , Química , Diálisis , Cinética , Modelos Teóricos , Espectrofotometría , Relación Estructura-Actividad
17.
Can Fam Physician ; 14(5): 44-8, 1968 May.
Artículo en Inglés | MEDLINE | ID: mdl-20468224
18.
West Indian med. j ; 5(4): 284-8, Dec. 1956.
Artículo en Inglés | MedCarib | ID: med-12881

RESUMEN

The first case of paratyphoid C infection in Jamaica is reported as a paratyphoid C osteomyelitis complicated by sickle cell crisis. The epidemiological implication of the above finding is of importance in view of the omission of paratyphoid organisms from the vaccine used in Jamaica. The high invasiveness and pathogenicity of Salmonella paratyphi C is noted. (AU)


Asunto(s)
Humanos , Adulto , Masculino , Osteomielitis/tratamiento farmacológico , Osteomielitis/cirugía , Salmonella paratyphi C/aislamiento & purificación , Jamaica , Anemia de Células Falciformes/terapia
19.
West Indian med. j ; 5(4): 256-64, Dec. 1956.
Artículo en Inglés | MedCarib | ID: med-12884

RESUMEN

The clinical features of diabetes in Jamaica, as exemplified by 103 cases admitted to the University College Hospital of the West Indies during 1955, are described. Diabetes is an important cause of hospital admissions in Jamaica. Three main types of diabetes, and a subgroup of the type II cases, are discussed. (AU)


Asunto(s)
Humanos , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Masculino , Femenino , Diabetes Mellitus Tipo 1/clasificación , Diabetes Mellitus Tipo 2/clasificación , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/mortalidad , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/mortalidad , Diabetes Mellitus Tipo 1/terapia , Jamaica , Admisión del Paciente
20.
West Indian med. j ; 5(3): 207-211, Sept.1956.
Artículo en Inglés | MedCarib | ID: med-12890

RESUMEN

The admissions to a male and female ward of the University College Hospital of the West Indies during 1955 have been analysed


Asunto(s)
Humanos , Masculino , Femenino , Admisión del Paciente/estadística & datos numéricos , Enfermedades Cardiovasculares , Enfermedades del Sistema Endocrino , Enfermedades Metabólicas , Jamaica
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