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11.
The phylogeny of howler monkeys (Alouatta, Platyrrhini): Reconstruction by multicolor cross-species chromosome painting 总被引:2,自引:0,他引:2
Edivaldo H. C. de Oliveira Michaela Neusser Wilsea B. Figueiredo Cleusa Nagamachi Julio Cesar Pieczarka Ives J. Sbalqueiro Johannes Wienberg Stefan Müller 《Chromosome research》2002,10(8):669-683
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca. 相似文献
12.
The tumor marker CA 15.3 was studied in 85 patients with liver cirrhosis. Nine patients (10.6%) had abnormal levels of CA 15.3 with the highest values in cases of Child's C patients. However, Child's classes were not significantly associated with the level of the antigen. We found significant correlations with some laboratory tests, especially IgA. All patients with an elevated CA 15.3 value also had abnormal levels of IgA, and multivariate analysis showed that IgA was the only independent factor associated with CA 15.3. Although IgA is a marker of alcoholic liver disease, other markers of alcoholism were not associated with CA 15.3. Cytolysis and cholestasis were not significantly associated with the CA 15.3 level, but liver dysfunction seemed to be involved. Liver disease does not substantially limit the usefulness of CA 15.3 in the cancer patient who also has liver cirrhosis, since both the percentage of abnormal values and the elevation of the serum levels are moderate in cirrhotic patients. 相似文献
13.
Elena del Olmo Carmen del Arco Alvaro Díaz Julio Pascual Guadalupe Mengod José M. Palacios Angel Pazos 《The European journal of neuroscience》1996,8(1):53-60
The pattern of pre- and postnatal appearance of 5-HT1D receptors throughout the different areas of the human brain was studied by quantitative in vitro autoradiography, using [125 I]GTI (serotonin O -carboxymethyl-glycyl-[125 I]tyrosinamide) as a ligand. The anatomical distribution of 5-HT1D receptors in neonatal, infant and children's brain was in good agreement with that observed in the adult, the basal ganglia and substantia nigra being the most intensely labelled areas. The development of these receptors throughout the human brain was mainly postnatal: low densities of [125 I]GTI binding sites were observed at the fetal/neonatal stage in most regions analyzed, in contrast with the high levels of labelling found in infant and children's brains. Indeed, in a number of regions, including the globus pallidus, substantia nigra and visual cortex, a peak of overexpression of 5-HT1D receptors was observed in the first decade of life. Such overexpression could support a regulatory role for 5-HT1D receptors in advanced periods of the CNS developmental process. Our results also indicate that the administration of drugs acting on 5-HT1D receptors during the early postnatal period of life could result in modifications of their properties, as these receptors are already functional in this period. 相似文献
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15.
Esther Fernndez Pedro Lpez de Castro Gustavo Tapia Julio Astudillo 《European journal of cardio-thoracic surgery》2008,33(5):937-938
We report the case of a patient who was operated on in February 2001. We performed a wedge resection of the upper right lobe. The pathologic examination demonstrated a lung adenocarcinoma (pT2N0M0, R0). We used staple line reinforcement material (ePTFE) during the operation because the patient had an important emphysema. We re-operated in January 2005 because during follow-up we observed a suspicious image that suggested a tumoral relapse. Histopathological study showed extrinsic material compatible with the one used in the original resection. 相似文献
16.
Eduardo M. Salinas Jorge Cebada Alberto Valdés Anoland Garateix Abel Aneiros Julio L. Alvarez 《Toxicon》1997,35(12):1699-1709
The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5–1 mg/ml it increased the L-type Ca current (ICaL) by 25–50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1–10 mg/ml). In this concentration range, Bainh markedly (≈75%) increased the inward-going rectifier current, IK1. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations. 相似文献
17.
Julio A. Ramirez 《Disease Management & Health Outcomes》2003,11(1):33-43
Several national and international organizations have developed and published guidelines for the treatment of patients with community-acquired pneumonia (CAP). Guidelines from Europe, the US, Canada and Latin America classify patients in different groups based on the severity of pneumonia, site of care and presence of risk factors for resistant organisms. The initial antibacterial therapy is designed to cover only the likely organisms able to infect a particular group of patients. An evaluation of current guidelines indicates that there are significant similarities in regard to classification of patients and initial antibacterial therapy. One objective of this review is to present the clinician with a practical approach to antibacterial selection based on current published guidelines for CAP.Although most of the care recommended in guidelines is evidence-based and associated with better clinical outcomes and/or decreased healthcare cost, there is still a significant gap between recommended care and actual care of patients with CAP. Dissemination of guidelines at the local level has proved to have a minimal effect in changing local practices. To bring the local care of patients with CAP closer to the care recommended in guidelines, it is necessary to have an appropriate plan for guideline implementation. This review provides the clinician and other healthcare decision-makers with a methodology for implementation of national guidelines at the local hospital level. 相似文献
18.
Pablo L. Joskowicz Alberto Muoz Julio Barrera Alejandro J. Müller 《Macromolecular chemistry and physics.》1995,196(1):385-398
Preparative temperature rising elution fractionation (TREF) on commercial linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) samples has been performed. The resulting fractions exhibited a bimodal and a unimodal distribution, respectively. Two LLDPE fractions of low (5 CH3/1000 C) and high (21 CH3/1000 C) short-chain branching content were solution-mixed with the LDPE central fraction (16 CH3/1000 C). Indirect evidence based on differential scanning calorimetry results suggest that the fractions with similar branch contents are more miscible than those with dissimilar ones. 相似文献
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20.
Free-living, Amphizoic and Opportunistic Amebas 总被引:9,自引:0,他引:9
Augusto Julio Martinez Govinda S. Visvesvara 《Brain pathology (Zurich, Switzerland)》1997,7(1):583-598
Amebas belonging to the genera Naegleria, Acanthamoeba and Balamuthia are free-living, amphizoic and opportunistic protozoa that are ubiquitous in nature. These amebas are found in soil, water and air samples from all over the world. Human infection due to these amebas involving brain, skin, lung and eyes has increased significantly during the last 10 years. The epidemiology, immunology, protozoology, pathology, and clinical features of the infections produced by these protozoa differ strikingly. Infection by the pathogenic Naegleria fowleri is acquired by exposure to polluted water in ponds, swimming pools and man-made lakes. Raised temperatures during the hot summer months or warm water from power plants facilitate the growth of N. fowleri. N. fowleri is a thermophilic ameba that grows well in tropical and subtropical climates. The CNS infection, called Primary Amebic Meningoencephalitis (PAM), produced by N. fowleri is characterized by an acute fulminant meningoencephalitis leading to death 3–7 days after exposure. Victims are healthy, young individuals with a history of recent water-related sport activities. The portal of entry is the olfactory neuroepithelium. The pathologic changes are an acute hemorrhagic necrotizing meningoencephalitis with modest purulent exudate, mainly at the base of the brain, brainstem and cerebellum. Trophozoites can be seen within the CNS lesions located mainly around blood vessels. Thus far 179 cases have been reported; 81 in the USA alone. Balamuthia mandrillaris and several species of Acanthamoeba are pathogenic “opportunistic” free-living amebas which cause Granulomatous Amebic Encephalitis (GAE) in humans and animals. GAE is an infection, usually seen in debilitated, malnourished individuals, in patients undergoing immunosuppressive therapy for organ transplants and in Acquired Immunodeficiency Syndrome (AIDS). The granulomatous component is negligible, particularly in immunocompromised individuals. Pathologically these amebas produce a patchy, chronic or subacute granulomatous encephalitis with the presence of trophozoites and cysts. The portal of entry is probably through the respiratory tract or an ulceration of the skin reaching the CNS by hematogenous spread. As of October 1, 1996, 166 cases 1103 due to Acanthamoeba and 63 due to Balamothial of GAE have been reported from around the world. Of these 103 cases due to Acanthamoeba (72 have been reported in the USA alone, > 50 in AIDS). It is well known that several species of Acanthamoeba can also produce, chronic sight threatening ulceration of the cornea called Acanthamoeba keratitis (AK), mostly in contact lens wearers or in individuals with minor corneal abrasions. Hundreds of cases of AK have been documented world wide. 相似文献