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41.
P. Cortina Greus J. L. Alfonso Sanchez I. Frasquet Pons C. Saiz Sanchez C. Cortes Vizcaino J. I. Gonzalez Arraez A. Sabater Pons S. Ruiz 《European journal of epidemiology》1992,8(6):770-775
After describing the evolution of mortality from ischaemic cardiopathy (IC) in Spain from 1951 to 1986, which is tending to stabilize in some age groups, and from cerebrovascular accidents (CVA), which is clearly declining, an attempt is made to relate these developments to the prevalence of the main risk factors (hypertension, cholesterol, tobacco) associated with IC and CVA. Certain advances, though of a limited number, have been made in recent years in the control of arterial hypertension in Spain, although campaigns on a national scale as in other countries have not been carried out. Regarding alimentary factors, there is an obvious increase in the consumption of food rich in proteins and animal fats, abandoning to a great extent the traditional Mediterranean diet, with health care action being limited to the improvement of nutrition education of the public. Furthermore, the consumption of tobacco has been increasing in Spain during the study period in spite of health legislation in force in recent years.It is therefore deduced that there is no obvious relationship between mortality due to IC and CVA and the prevalence of the main risk factors associated with these diseases, especially when taking into account that preventive actions on a public health level have been very limited.Corresponding author. 相似文献
42.
The acrosomal status of human spermatozoa was studied in relation to the score of the sperm penetration assay (SPA) at low-temperature (4 degrees C) incubation for induction and synchronization of the acrosome reaction (AR) and the incubation time of spermatozoa in conventional SPA. Spermatozoa were collected from 18 patients, selected by the "swim-up" method and treated in three different ways: (1) short-term incubation group (SIG): 3 h incubation at 37 degrees C, and (2) long-term incubation group (LIG): 20 h incubation at 37 degrees C, and (3) low temperature group (LTG): 24 h incubation at 4 degrees C followed by additional incubation at 37 degrees C for 3 h. The conventional methods of incubation, i.e. SIG (3 h) and LIG (20 h) did not show any significant differences as evaluated by the sperm penetration rate and the number of decondensing sperm heads per oocyte. In contrast, in the LTG all parameters were significantly increased, especially those of penetration rate (p less than 0.0005) and decondensing sperm heads per oocyte (p less than 0.0005). The percentage of AR significantly increased (p less than 0.0005) in the LTG (14.7%) compared with SIG (6.1%) and LIG (10.6%). A significant correlation was demonstrated between AR and the parameters used for evaluation of the SPA. The penetration rate (Spearman test, r = 0.462, n = 54, p less than 0.003) was the most significant parameter correlated with AR. It would appear that only human spermatozoa having completed AR are capable of fusing with the zona-free hamster ova.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
R. Sanchez E. Toepfer-Petersen R. J. Aitken and Dr W.-B. Schill Professor 《Andrologia》1991,23(3):197-203
The acrosome reaction of human spermatozoa was induced by changes of temperature. Spermatozoa were collected from fertile donors and a patient group, and selected by the "swim-up" method. The spermatozoa were treated in two different ways: Protocol I: 24 hours at room temperature followed by additional incubation at 37 degrees C for 3 hours (control), and protocol II: 24 hours at 4 degrees C followed by additional incubation at 37 degrees C for 3 hours. The acrosome reaction of the viable spermatozoa was evaluated by a new method utilizing indirect immunofluorescence with anti-outer acrosomal membrane antibodies and exposure to a hypo-osmotic medium. In fertile donors as well as in the patient group, significant induction of the acrosome reaction (20%) was evident after exposure to low temperature (4 degrees C). The spontaneous rate of acrosome reaction in the control group was below 7%. 相似文献
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45.
S. Hjorth A. Carlsson P. Lindberg D. Sanchez H. Wikström L. -E. Arvidsson U. Hacksell J. L. G. Nilsson 《Journal of neural transmission (Vienna, Austria : 1996)》1982,55(3):169-188
Summary It was demonstrated that the simplified ergot congener 8-hydroxy-2-(di-n-propylamino)tetralin, 8-OH-DPAT, is able to elicit pronounced biochemical and behavioural alterations indicative of central serotoninomimetic activity. Since these effects are resistant to prior monoamine depletion and/or synthesis inhibition by means of reserpine and-propyldopacetamide (H22/54), respectively, they are most likely to be attributable to direct serotonin-receptor agonism by 8-OH-DPAT. With regard to central 5-HT neurotransmission the effects of 8-OH-DPAT-increased 5-HT levels, decreased 5-HIAA levels, 5-HT-synthesis rate and 5-HT utilization and inhibited 5-HT neuronal firing-are virtually identical, and comparable in potency, to those reported to result from the administration of lisuride or LSD. In contrast, however, to lisuride and LSD (included for comparative purposes in this study) as well as to several differently N-substituted, 5,6-dihydroxy, 6,7-dihydroxy and 5-, 6- and 7-monohydroxy 2-aminotetralins, 8-OH-DPAT lacks appreciable effects on central catecholamine receptors. The compound may thus be regarded the most potent, selective centrally acting 5-HT agonist described to date. accordance with this it was shown that the full-blown 5-HT-like behaviour syndrome induced by 8-OH-DPAT cannot be antagonized by reserpin phenoxybenzamine, propranolol and haloperidol. In addition, of the truputative 5-HT-receptor blockers cyproheptadine, methergoline and methrothepin only the latter was able to counteract the 8-OH-DPAT-induce syndrome. The results are discussed in relation to the recent subclassification of central 5-HT receptor sites.A comparison between the chemical structures and biological activities for different fragments of the ergot nucleus was also made. The data suggest, in that while the role of the A ring in the ergot structure for dopaminer activity at present is unclear, this ring may be important for the 5-HT-receptor activity like in e.g. lisuride and LSD.Moreover, based on the present results and literature reports, it is speculated that a selective 5-HT-receptor agonist such as 8-OH-DPAT would be liable to induce hallucinations in man.Presented in part at the 19th ACNP meeting, San Juan, December 15–19,1980. [Psychoph. Bull.17, 180–183 (1981).] 相似文献
46.
Executive function and verbal working memory in adolescents with closed head injury (CHI) 总被引:3,自引:0,他引:3
The relationship between executive function (EF) and working memory (WM) was studied in eight adolescents with closed head injury (CHI) and eight controls, matched for age, gender and socioeconomic status (SES). A cognitive-linguistic test (Scales of Cognitive Ability for Traumatic Brain Injury, SCATBI) was used to group CHI participants by severity. EF was tested with a measure of daily functioning (Pro-Ex) and WM was tested with a recognition memory task (RMT). When all subject test data were grouped, a positive linear correlation was found for the Pro-Ex and the RMT. A strongto-moderate positive correlation was found for components of the EF measure and the RMT. Severity of injury influenced test performance for both the EF and WM measures, with a significance between group effects found on the RMT task. Results indicate a relationship between executive function and working memory, severity of injury and test performance and the need to assess EF of CHI adolescents with a measure of daily functioning. 相似文献
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49.
Measurement of albumin and low molecular weight proteins in the urine of newborn infants using a cotton wool ball collection method 总被引:2,自引:0,他引:2
Objective : The aim of this study was to investigate the inter-relationship between urinary excretion of alpha-1-microglobulin (AIM), retinol-binding protein (RBP) and albumin in term and premature neonates, with urine collected into cotton wool balls and extracted by a novel method. Subjects and methods : Sixty-four infants were studied on the first day of life; 26 had been born at term (37–42 weeks gestation) and 38 prematurely (24–28 weeks n = 16, 29–36 weeks n = 22). Urine collected into cotton wool balls was analysed following a new detergent extraction method, which resulted in a recovery rate of 94–107% for albumin, AIM, RBP and creatinine. Results : Urinary protein excretion, expressed as a ratio to urinary creatinine, decreased significantly with increasing gestational age (24–28 weeks, 29–36 weeks, 37–42 weeks: albuminxreatinine ratio mg/mmol mean 96.9, 31.7, 19.3; AIM: creatinine ratio mg/mmol mean 99.3, 37.0, 7.8; RBP: creatinine ratio mg/mmol mean 16.2, 3.8, and <0.01, below the limit of detection, respectively). When results were corrected for birthweight, this gestation-associated effect was still present for A1M and RBP, but not for albumin. In premature infants there was a significant positive correlation between AIM: creatinine ratio and RBP: creatinine ratio ( r = 0.85), and also between albumin and both AIM and RBP ( r = 0.82 and 0.77). Conclusion : Increased excretion of AIM, RBP and albumin at earlier gestational ages is probably due to proximal tubular immaturity, although tubular damage and also glomerular dysfunction cannot be excluded as possible explanations. 相似文献
50.
Forte L Migliaccio G Sanchez M Migliaccio AR Passarelli AM Amadori S 《Annali dell'Istituto superiore di sanità》2000,36(3):333-342
The small volume of placental/umbilical cord blood (PUCB) collectable restricts the use of these stem cells to pediatric transplantation. To extend the use of PUCB to adult recipients, many laboratories are investigating the feasibility of ex vivo PUCB expansion. The present study analyses the effects that PUCB banking cell manipulations (cell sedimentation, cryopreservation and thawing, mononuclear and CD34+ cell isolation) have on the number, viability and ex vivo expansion potential of PUCB cells. The results presented indicate the necessity of an open discussion on whether procedures used for handling the cells in PUCB banks can be extrapolated or not as such to the clinical use of ex vivo expanded PUCB. 相似文献