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71.
In this article, the authors present an analysis of causes of death in Spain and Portugal in 1984 based on a calculation of the "years of potential life lost" (YPLL) between the first and the 70th birthdays, the latter age corresponding approximately to the average life expectancy in both countries. This analysis of the YPLL led to a substantially different ranking of the main causes of death, based on what might be termed "premature mortality" compared with that obtained from more conventional mortality indices. According to this criterion, which is especially appropriate for the planning and evaluation of health interventions, the main causes of premature death (1-69 years) in the two countries of the Iberian peninsula are malignant tumours and, particularly in Portugal, violent deaths (especially motor-vehicle accidents, but also suicides). This is in contrast to the predominance of cardiovascular diseases indicated by other weightings of age-specific mortality rates. Portugal shows significantly worse YPLL rates than Spain not only for general mortality (45% higher than in Spain), but also for several major groups of causes. In Spain only malignant neoplasms, diabetes and chronic rheumatic heart diseases show higher specific mortality rates than in Portugal, based on traditional mortality indicators.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
72.
73.
The intravenous injection of rabbit anti-rat kidney serum in rats produces, with a latency of 30 to 60 seconds, the triad sinus bradycardia (or S-A blockade), systemic hypotension and apnea. Recordings of the intracardiac pressures showed a rise in the right and a simultaneous fall in the left ventricular pressure, 30 to 60 seconds after the serum injection. These initial effects were followed by pulmonary edema and death. Bilateral vagotomy prevented the bradycardia and apnea, but not the intracardiac changes, edema and death. Atropine also prevented the bradycardia, but not the apnea, edema and death. Experiments using alpha and beta adrenergic blocking agents seem to indicate that the edema is not caused by the release of catecholamines. It is suggested that the edema could be explained by a rise in the pulmonary capillary pressure, due to the antigen-antibody reaction. The triad bradycardia, systemic hypotension and apnea seems to be the first sign of the pulmonary edema, is reflex in nature, and is assumed to be due to stimulation of J receptors in the lungs, by a mechanical effect (edema). Phenylbutazone and acetylsalicylic acid give a partial protection against the pulmonary edema. Ultramorphological observations of lungs with edema were described.  相似文献   
74.
Down syndrome is the most common human chromosomal disorder. Among clinical findings, one constant concern is the high prevalence of gastrointestinal system alterations. The aim of this study was to determine the prevalence of gastrointestinal disorders at a Down syndrome outpatient clinic during a 10‐year follow‐up period. Data from medical files were retrospectively reviewed from 1,207 patients. Gastrointestinal changes occurred in 612 (50.7%). The most prevalent disorder was chronic intestinal constipation. Intestinal parasite occurred in 22% (mainly giardiasis), gastroesophageal reflux disease in 14%, digestive tract malformations occurred in 5%: 13 cases of duodenal atresia, 8 of imperforate anus, 4 annular pancreases, 2 congenital megacolon, 2 esophageal atresias, 2 esophageal compression by anomalous subclavian and 1 case of duodenal membrane. We had 38/1,207 (3.1%) patients with difficulty in sucking and only three with dysphagia that resolved before the second year of life. Peptic ulcer disease, celiac disease, and biliary lithiasis were less prevalent with 3% each. Awareness of the high prevalence of gastrointestinal disorders promotes outstanding clinical follow‐up as well as adequate development and greater quality of life for patients with Down syndrome and their families.  相似文献   
75.
BACKGROUND: Vitrification of human blastocysts has been successfully applied using grids, straws and cryoloops. We assessed the survival rate of human compacted morulae and early blastocysts vitrified in pipette tips with a smaller inner diameter and solution volume than the previously described open pulled straw (OPS) method. METHODS: Excess day 5 human embryos (n = 63) were experimentally vitrified in vessels. Embryos were incubated at 37 degrees C with sperm preparation medium (SPM) for 1 min, SPM + 7.5% ethylene glycol (EG)/dimethylsulphoxide (DMSO) for 3 min, and SPM + 16.5% EG + 16.5% DMSO + 0.67 mol/l sucrose for 25 s. They were then aspirated (0.5 microl) into a plastic micropipette tip (0.36 mm inner diameter), exposed to liquid nitrogen (LN(2)) vapour for 2 min before being placed into a pre-cooled cryotube, which was then closed and plunged into LN(2). Embryos were warmed and diluted using 0.33 mol/l and 0.2 mol/l sucrose. RESULTS: The survival rate for compacted morulae was 73% (22/30) and 82% (27/33) for early blastocysts. CONCLUSIONS: The survival rates of human compacted morulae and early blastocysts after vitrification with this simple technique are similar to those reported in the literature achieved by slow cooling and other vitrification protocols.  相似文献   
76.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
77.
Accurate diagnosis of oral hairy leukoplakia (OHL) is important because it may be an early indicator of undiagnosed HIV infection; moreover, it may be a prognostic indicator. Our purpose was to investigate the histopathologic features of subclinical OHL and to evaluate and support the rationale of detecting subclinical OHL with cytopathology. The Epstein-Barr virus (EBV) was detected by immunohistochemistry and in situ hybridization in 4 cases of macroscopically normal lateral borders of tongue mucosa from 8 AIDS necropsies and in none of 8 controls. The histopathologic features were specific when based on nuclear changes: Cowdry type A inclusion, ground glass, and nuclear beading. Smears were obtained from 50 patients with AIDS, without OHL, from the scraping of lateral borders of the tongue. Numerous clusters of the cells were associated with Candida organisms (30% of cases). Nuclear changes were observed in 12 patients (24%) on both sides of the tongue. We describe the histopathologic features of subclinical OHL, and our observations suggest that cytopathology can detect OHL in the subclinical phase.  相似文献   
78.
BACKGROUND: Chronic airway inflammation is a fundamental feature of bronchial asthma, which is characterized by the accumulation and activation of inflammatory cells, such as mast cells and eosinophils, that are tightly regulated by TH2 cytokines and chemokines. Recently, we demonstrated, in a murine model of asthma with immunosuppressed mice reconstituted with antigen-specific IgE or IgG1 antibodies, that IgE, but not IgG1, participates in potentiation of airway inflammation and induction of airway hyperreactivity (AHR). The IgG1 antibody, however, did not elicit passive cutaneous anaphylactic reactions, which was in contrast to IgE. OBJECTIVES: Because 2 types of murine IgG1 have been demonstrated with regard to anaphylactic activity, the present experiments were undertaken to determine the role of anaphylactic and nonanaphylactic IgG1 antibodies in the development of antigen-induced eosinophilia and AHR in this model. METHODS: Dinitrophenyl-conjugated, heat-coagulated hen's egg white was implanted in immunosuppressed mice reconstituted with anaphylactic or nonanaphylactic IgG1. Intratracheal challenge with aggregated dinitrophenyl-ovalbumin was performed on day 14, and lung inflammatory and mechanical parameters were evaluated after 48 hours. RESULTS: Our results demonstrated that reconstitution of immunosuppressed mice with anaphylactic IgG1 antibodies in contrast to nonanaphylactic IgG1 antibodies potentiates their ability to have pulmonary eosinophilic inflammation and AHR. IL-5 and eotaxin levels in bronchoalveolar lavage fluid from anaphylactic IgG1-reconstituted mice were also higher than those in nonanaphylactic IgG1-reconstituted mice. CONCLUSIONS: These results indicate that the anaphylactic property of murine IgG1 molecules is essential for their capacity to enhance lung eosinophilic inflammation and to induce AHR.  相似文献   
79.
Ostrich pericardium, sutured using a telescoping or overlapping technique, was studied to determine its mechanical behavior. From each of 12 pericardial sacs, four contiguous strips were cut longitudinally, from root to apex, and another four contiguous strips were cut in transverse direction. One of the strips in each set of four was used as an unsutured control and the remaining three were sutured by overlapping 0.5 cm of the tissue and sewing with Gore-tex, Prolene or Pronova. These 96 samples were then subjected to tensile testing along their major axes until rupture. The tensile stresses recorded in the suture materials at the moment tears appeared in the pericardium ranged between 55.99 MPa and 70.23 MPa for Gore-tex in samples cut in the two directions. Shear stress became ostensible at 56 MPa, with clearly evident tears. However, microfracture of the collagen fibers must be produced at much lower stress levels. The comparison of the resistance in kilograms (machine-imposed), without taking into account the sections in which the load was applied, demonstrated only a slight loss of load when the telescoping suture was employed in ostrich pericardium samples. Ostrich pericardium may continue to be an alternative biological material for the construction of heart valve leaflets.  相似文献   
80.
2 mg/kg melanotan II (MTII, administered i.p.), a cyclic peptide analog of α-melanocyte stimulating hormone, at a single dose increased grooming in naive rats placed in an unfamiliar open-field device without changing locomotion or rearing. Male rats exposed to restraint/immobilization stress (IS) for 1 h on three consecutive days displayed increased grooming after the second stressor exposure, compared to pre-stress levels. MTII, administered to the rats after IS, enhanced the grooming response compared both to the pre- and post-stress values. The increase was greatest after the first dose and declined over the following two applications. As to the locomotion of rats in the entire experimental space, IS reduced the distance moved only after the first two stressor exposures; MTII did not influence these alterations. Locomotion in the central part of arena was not reduced by the stressor or by MTII, on the contrary, there was an increase in both groups after the third intervention. The only observed change in rearing was an increase in the MTII group after the third restraint exposure. Thus, MTII selectively increased grooming without markedly affecting the spatio-temporal structure of locomotor behavior in the open-field. The decline of MTII enhanced grooming over the three test days may be interpreted in terms of adaptation to the stressor and of the developing tolerance to the peptide.  相似文献   
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