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1.
Nature ; 434(7029): 45-9, 2005 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-15744293

RESUMEN

The nations of the world have set themselves a target of reducing the rate of biodiversity loss by 2010. Here, we propose a biodiversity intactness index (BII) for assessing progress towards this target that is simple and practical--but sensitive to important factors that influence biodiversity status--and which satisfies the criteria for policy relevance set by the Convention on Biological Diversity. Application of the BII is demonstrated on a large region (4 x 10(6) km2) of southern Africa. The BII score in the year 2000 is about 84%: in other words, averaged across all plant and vertebrate species in the region, populations have declined to 84% of their presumed pre-modern levels. The taxonomic group with the greatest loss is mammals, at 71% of pre-modern levels, and the ecosystem type with the greatest loss is grassland, with 74% of its former populations remaining. During the 1990s, a population decline of 0.8% is estimated to have occurred.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Ecología/métodos , Cooperación Internacional , África Austral , Algoritmos , Animales , Recolección de Datos , Geografía , Mamíferos/fisiología , Fenómenos Fisiológicos de las Plantas , Dinámica Poblacional , Sensibilidad y Especificidad , Factores de Tiempo
2.
Science ; 214(4519): 441-3, 1981 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-17730245

RESUMEN

Q-mode factor analysis has been used to partition the variability of environmentally active metals in Delaware Bay sediments. Three factors, identified as a natural background source, an oceanic or seawater source, and an estuarine source, account for 96 percent of the metal variability.

3.
Science ; 223(4631): 22-7, 1984 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-17752972

RESUMEN

Anoxia occurs annually in deeper waters of the central portion of the Chesapeake Bay and presently extends from Baltimore to the mouth of the Potomac estuary. This condition, which encompasses some 5 billion cubic meters of water and lasts from May to September, is the result of increased stratification of the water column in early spring, with consequent curtailment of reoxygenation of the bottom waters across the halocline, and benthic decay of organic detritus accumulated from plankton blooms of the previous summer and fall. The Chesapeake Bay anoxia appears to have had significant ecological effects on many marine species, including several of economic importance.

4.
Mil Med ; 174(1): 61-75, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19216300

RESUMEN

Using a postpartum survey, comparing singles to married, we sought to expand existing information on pregnancy occurring among active duty service women. The study instrument was a 59-question survey distributed in the initial 24 hours postpartum and collected prior to discharge. The majority affirmed that pregnancy had not changed career plans. Singles did not consider their commands supportive during pregnancy, (p=.04). Eighty-two percent of pregnancies among singles were unplanned, (p=.006). The majority of single pregnancies occurred while assigned to operational units, (p=.004); and during their first enlistment, (p<.001). Three-quarters of all singles required Women Infants and Children (WIC) financial support, (p<.001); and fewer fathers were, or planned to be involved, (p<.001). Unplanned pregnancy, contraceptive failure, and pregnancy complications highlight areas of organizational and individual concern warranting further study among active duty.


Asunto(s)
Personal Militar , Periodo Posparto , Embarazo no Planeado , Adulto , Femenino , Necesidades y Demandas de Servicios de Salud , Humanos , Embarazo , Complicaciones del Embarazo , Encuestas y Cuestionarios , Virginia , Adulto Joven
5.
J Reprod Med ; 53(5): 378-81, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18567288

RESUMEN

BACKGROUND: Concurrent ectopic pregnancy and acute appendicitis is rarely encountered. Since 1960, only 22 cases have been reported. No case of concurrent interstitial ectopic pregnancy and appendicitis has ever been reported. CASE: A 24-year-old, African American woman, gravida 4, para 3, had a right interstitial ectopic pregnancy. She was managed as an inpatient with parenteral methotrexate and her beta-human chorionic gonadotropin level decreased appropriately. She was discharged 3 days after treatment but subsequently returned with right lower quadrant pain, nausea, vomiting and fever. The patient underwent laparoscopy with removal of a suppurative appendix. A stable interstitial ectopic pregnancy was visualized and left in situ. CONCLUSION: The discipline to consider concomitant abdominal pathology is paramount. The perceived rarity of an ectopic pregnancy and appendicitis should not obscure a thorough clinical evaluation.


Asunto(s)
Apendicitis/complicaciones , Apendicitis/diagnóstico , Embarazo Ectópico/diagnóstico , Embarazo Ectópico/etiología , Adulto , Apendicitis/terapia , Femenino , Humanos , Embarazo , Embarazo Ectópico/terapia
6.
Oncogene ; 11(7): 1249-54, 1995 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-7478544

RESUMEN

We used PCR amplification of tandem repeats to study the pattern of allelic loss in borderline and invasive ovarian epithelial tumors using 12 primer pairs to generate a detailed deletion map of chromosome 9p. In the invasive ovarian carcinomas, there were three regions displaying high frequency of loss of heterozygosity (LOH) ranging from 31-38%. In contrast, LOH was a rare event among the borderline ovarian tumors, with one region revealing a rate of 20% and the remaining regions only 0-8% LOH. Therefore, allelic loss does not seem to be important for the development of borderline ovarian tumors. We also examined p16 gene expression and mutations in ovarian cancer cell lines and invasive and borderline ovarian tumor tissues. Southern blot analysis revealed no losses of the p16 gene in either the invasive or borderline ovarian tumors. However, the ovarian carcinoma cell lines showed a 50% homozygous deletion rate. SSCP analysis detected a mobility shift in only one (borderline) tumor. Since the primary invasive ovarian tumors did not show any deletions or mutations, it appears that p16 does not play a role in the pathogenesis of these tumors.


Asunto(s)
Proteínas Portadoras/genética , Deleción Cromosómica , Cromosomas Humanos Par 9 , Invasividad Neoplásica/genética , Neoplasias Ováricas/genética , Línea Celular Transformada , Células Cultivadas , Mapeo Cromosómico , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Femenino , Heterocigoto , Humanos , Neoplasias Ováricas/patología , Ovario/citología , Ovario/metabolismo , Reacción en Cadena de la Polimerasa
7.
Mech Ageing Dev ; 60(3): 285-93, 1991 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-1661358

RESUMEN

The concentration of mitochondria decreases in the heart as rodents age from maturity to senescence. The reason for this change is not known. One purpose of the present study was to determine if cytochrome c mRNA, representative of proteins of the inner mitochondrial membrane, decreased in the hearts of Fischer 344 rats as they aged from 12 to 24 months. Twenty-two percent less cytochrome c mRNA existed per given quantity of extracted RNA from the heart in 24-month-old rats as compared with the 12-month-old group. No change in the quantities of cardiac alpha-actin mRNA, Ca2+/calmodulin protein kinase II mRNA or 18S rRNA was noted between 12- and 24-month-old hearts. Thus, the decrease in cytochrome c mRNA suggests that decreases in mRNAs for proteins of the inner mitochondrial membrane could play some role in the diminished concentration of mitochondria that exists in the senescent heart.


Asunto(s)
Envejecimiento/metabolismo , Grupo Citocromo c/metabolismo , Miocardio/metabolismo , ARN Mensajero/metabolismo , Actinas/metabolismo , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina , Masculino , Proteínas Quinasas/metabolismo , ARN Ribosómico 18S/metabolismo , Ratas , Ratas Endogámicas F344
8.
Thromb Haemost ; 35(2): 274-88, 1976 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-989628

RESUMEN

The theoretical basis for determining the number of antibody sites on antigen molecules is examined. The theoretical considerations are applied to factor VIII molecules. Examples based on data available at the Oxford Haemophilia Centre are calculated to illustrate the approach. It is concluded that there are few sites on each factor VIII molecule for human antibody. The three antibodies for which reasonable data were available suggest 1-3 sites for human antibody. The data for rabbit antibody suggest 5-6 sites per factor VIII molecule.


Asunto(s)
Sitios de Unión de Anticuerpos , Factor VIII/inmunología , Absorción , Reacciones Antígeno-Anticuerpo , Humanos , Modelos Biológicos
9.
J Clin Pathol ; 21(2): 160-5, 1968 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-4972271

RESUMEN

Three patients with Christmas disease whose plasma was shown to have a prolonged one-stage prothrombin time with ox brain thromboplastin have been investigated. These patients have an inhibitor for the reaction between factor X, factor VII, and ox brain extract. The abnormal constituent responsible for this inhibitor appears to be factor IX whuch is functionally inactive but antigenically indistinguishable from normal factor IX. It is proposed that patients might be classified into haemophilia B(+) for patients with this defect (Christmas disease(+)) and haemophilia B(-) (Christmas disease(-)) for patients who have classical Christmas disease.


Asunto(s)
Factor IX/análisis , Hemofilia B/sangre , Animales , Antígenos , Pruebas de Coagulación Sanguínea , Bovinos , Factor VII/análisis , Factor X/análisis , Hemofilia B/clasificación , Hemofilia B/etiología , Humanos , Inmunodifusión , Protrombina/análisis , Tromboplastina
10.
J Appl Physiol (1985) ; 74(1): 410-4, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8444721

RESUMEN

The purpose of the study was to note whether insulin-like growth factor (IGF) immunoreactivity increased after eccentric contractions. IGF immunoreactivity in the rat tibialis anterior muscle was measured on 5 successive days (4-5 rats/group, n = 28) after an acute bout of 192 eccentric contractions elicited by electrical stimulation. The muscle tissue sections were immunocytochemically processed with rabbit anti-human IGF-I serum. Immunoreactivity was analyzed with videomicroscopy and computer-aided image processing. Four days after eccentric contractions, IGF immunoreactivity was significantly higher than control [0.081 +/- 0.073 (SD) absorbance at 480 nm vs. 0.026 +/- 0.018; P < 0.05]. The increases in IGF-I immunoreactivity were mostly within the muscle fibers. These results suggest that an acute bout of eccentric exercise increases IGF-I immunoreactivity in rat type II muscle 4 days postexercise.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Músculos/metabolismo , Esfuerzo Físico/fisiología , Animales , Femenino , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/inmunología , Contracción Muscular/fisiología , Proteínas Musculares/biosíntesis , Músculos/anatomía & histología , Ratas , Ratas Sprague-Dawley
11.
Pharmacotherapy ; 21(6): 731-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11401185

RESUMEN

We designed this project to determine community pharmacists' opinions regarding the challenges and motivations of their recent participation in a pharmacy practice-based research study At the conclusion of a randomized, multicenter study, 87 community pharmacist-investigators were sent a questionnaire that explored four areas: motivating factors to participate, barriers to participation, communication tools used by study coordinators, and design issues for future studies. Fifty-eight (67%) completed questionnaires were returned. Key factors motivating participation in the study were desire to improve the profession and opportunity to learn. Time was the greatest barrier to participation. Pharmacy practice-based research has two distinct advantages. First, it translates clinical knowledge into direct application in the community. Second, it provides needed data to demonstrate the value of enhanced pharmacy practice. Thorough understanding of pharmacists' opinions is necessary to optimize the design of future studies.


Asunto(s)
Actitud del Personal de Salud , Servicios Comunitarios de Farmacia/estadística & datos numéricos , Investigación sobre Servicios de Salud , Farmacéuticos/psicología , Encuestas y Cuestionarios , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Humanos , Selección de Paciente , Vigilancia de la Población , Proyectos de Investigación , Factores de Riesgo
12.
J Am Osteopath Assoc ; 101(8): 450-3, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11526879

RESUMEN

Anal duct carcinoma, also known as anal gland carcinoma or adenocarcinoma of the anal canal, is an unusual anal cancer that accounts for approximately 0.1% of all gastrointestinal cancers. Delays in diagnosis most likely account for the poor prognosis associated with this cancer. Presenting symptoms often mimic those of more common benign anorectal pathologic processes. Multimodality treatment that includes surgery, chemotherapy, and radiation therapy is often recommended. The authors describe a typical case of anal duct carcinoma and its management. They also discuss the findings of a survey of the combined experience of members of the American Osteopathic College of Proctology and review the literature.


Asunto(s)
Adenocarcinoma , Neoplasias del Ano , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Neoplasias del Ano/diagnóstico , Neoplasias del Ano/terapia , Terapia Combinada , Resultado Fatal , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad
13.
J Miss State Med Assoc ; 31(4): 127-30, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2332891

RESUMEN

Communications between physician and patient have been protected from disclosure to third parties with the enactment of state statutes. The medical privilege, as it is commonly known, now embodied in Rule 503 of the Mississippi Rules of Evidence, contains the limiting language that the privilege is waived only to the extent that the patient places his medical condition at issue in a judicial proceeding. The authors note that this oftentimes forces the physician to make difficult decisions concerning what information, if any, is to be disclosed to an outsider to the physician-patient relationship. It is therefore prudent for the physician to insist upon a carefully worded written authorization, executed by the patient, prefatory to release of any such information.


Asunto(s)
Confidencialidad/legislación & jurisprudencia , Documentación , Humanos , Mississippi
17.
Dev Med Child Neurol ; 48(8): 677-82, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16836781

RESUMEN

Following the introduction of combination antiretroviral therapy, children vertically infected with the human immunodeficiency virus (HIV-1) living in the developed world are surviving into adult life. This paper reviews the neurodevelopmental outcomes of 62 consecutively-presenting children with HIV-1 infection diagnosed before 3 years of age (32 males, 30 females; median age at presentation 6 mo). Neurological and developmental data are presented with immunological and virological responses to antiretroviral therapy. Fourteen children (22%) had abnormal neurological signs and 25 (40%) demonstrated significant developmental delay on standardized developmental assessments. Children presenting with more severe HIV-1 disease and immune compromise had significantly more abnormal neurological signs and developmental delays than children presenting with milder HIV-1 symptomatology. Immune function, control of HIV-1 viral replication, and growth parameters improved with antiretroviral therapy (median age at last follow-up 7 y 3 mo); however, abnormal neurological signs and significant gross motor difficulties persisted.


Asunto(s)
Complejo SIDA Demencia/prevención & control , Fármacos Anti-VIH/uso terapéutico , Discapacidades del Desarrollo/etiología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Complejo SIDA Demencia/tratamiento farmacológico , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Distribución de Chi-Cuadrado , Desarrollo Infantil , Preescolar , Discapacidades del Desarrollo/prevención & control , Femenino , Estudios de Seguimiento , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Carga Viral
18.
Philos Trans R Soc Lond B Biol Sci ; 360(1454): 425-41, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-15814355

RESUMEN

The Southern African Millennium Ecosystem Assessment (SAfMA) evaluated the relationships between ecosystem services and human well-being at multiple scales, ranging from local through to sub-continental. Trends in ecosystem services (fresh water, food, fuel-wood, cultural and biodiversity) over the period 1990-2000 were mixed across scales. Freshwater resources appear strained across the continent with large numbers of people not securing adequate supplies, especially of good quality water. This translates to high infant mortality patterns across the region. In some areas, the use of water resources for irrigated agriculture and urban-industrial expansion is taking place at considerable cost to the quality and quantity of freshwater available to ecosystems and for domestic use. Staple cereal production across the region has increased but was outstripped by population growth while protein malnutrition is on the rise. The much-anticipated wood-fuel crisis on the subcontinent has not materialized but some areas are experiencing shortages while numerous others remain vulnerable. Cultural benefits of biodiversity are considerable, though hard to quantify or track over time. Biodiversity resources remain at reasonable levels, but are declining faster than reflected in species extinction rates and appear highly sensitive to land-use decisions. The SAfMA sub-global assessment provided an opportunity to experiment with innovative ways to assess ecosystem services including the use of supply-demand surfaces, service sources and sink areas, priority areas for service provision, service 'hotspots' and trade-off assessments.


Asunto(s)
Conservación de los Recursos Naturales/tendencias , Ecosistema , Ambiente , Abastecimiento de Alimentos/estadística & datos numéricos , Abastecimiento de Agua/estadística & datos numéricos , Agricultura/tendencias , Demografía , Agua Dulce , Geografía , Factores Socioeconómicos , Sudáfrica , Madera
19.
Br J Haematol ; 35(4): 487-504, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-871406

RESUMEN

A study has been made by the Haemophilia Centre Directors of the United Kingdom and Northern Ireland. From 1969 to 1974 2600 patients with haemophilia A and 388 with haemophilia B attended Haemophilia Centres for treatment. Of these patients, 71 are known to have died in the survey period. A record is presented of the amounts and types of therapeutic materials used each year during this time. The incidenceof jaundice and anti-factor VIII and anti-factor IX antibodies was recorded.


Asunto(s)
Factor IX/uso terapéutico , Factor VIII/uso terapéutico , Hemofilia A/terapia , Hemofilia B/terapia , Adolescente , Adulto , Anciano , Anticuerpos/análisis , Niño , Preescolar , Factor IX/inmunología , Factor VIII/inmunología , Factor VIII/provisión & distribución , Hemofilia A/epidemiología , Hemofilia A/mortalidad , Hemofilia B/epidemiología , Hemofilia B/mortalidad , Hepatitis Viral Humana/complicaciones , Servicios de Atención de Salud a Domicilio , Humanos , Lactante , Recién Nacido , Ictericia/complicaciones , Masculino , Persona de Mediana Edad , Reino Unido
20.
Planta ; 128(3): 271-3, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24430758

RESUMEN

Extracts from citrus [Citrus sinensis (L.) Osbeck] pedicles rated as containing polygalacturonase and cellulase gave activities both as measured with carboxymethylcellulose and with sodium polypectate. Gel electrophrosis of the extract demonstrated two region areas that contained cellulytic activity.

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