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991.
Van Leeuwen YD Düsman H Mol SS Pollemans MC Drop MJ Grol RP Van Der Vleuten CP 《Advances in health sciences education : theory and practice》1997,2(1):61-70
Objectives: The relation between the content of postgraduate training for general practice and the outcome in terms of the growth in knowledge of trainees was investigated. The training variables included were: (1) the number of patients seen per day, (2) the trainer, (3) the practice and (4) the theoretical curriculum.Methods: Subjects were 58 trainee-trainer pairs. Growth in knowledge was assessed by two written tests administered with eight months interval. Training variables were evaluated by means of questionnaires and logbook-registration. The correlation was explored between each of the training variables and the knowledge tests scores. To correct for interactional effects, a step-wise multiple regression analysis was performed with the second test as dependent variable and the first test as well as the training variables as independent variables.Results: Significant growth in knowledge was demonstrated. Non of all training variables investigated explained the variance in scores on the second test equally good or better than the scores on the entry test.Conclusions: The impact of the separate training-components on the growth in knowledge, remains unclear. We may speculate, that the sort of knowledge assessed with the written literature based true/false test is different from the sort of knowledge transferred during every day training: evidence based knowledge versus experience based knowledge. Equally valid is the conclusion that these findings fit into the theory that in adult learning the outcome is more learner than teacher dependent.This revised version was published online in September 2005 with corrections to the Cover Date. 相似文献
992.
Maria A. Ros Domingo Macias John F. Fallon Juan M. Hurle 《Anatomy and embryology》1994,190(4):375-382
By in situ hybridization we studied the expression patterns of Msx and Hoxd genes during the late development of the chick leg autopodium (foot) and compared them to patterns during the experimental development of interdigital extra digits. Extra digits are induced in the third interdigital space after various experimental manipulations, such as transient isolation of the interdigit, or removal of the interdigital marginal ectoderm and mesoderm. Msx1 and Msx2 are normally expressed in the interdigital tissue programmed to die. Our experiment changes the fate of the interdigital tissue from cell death to chondrogenesis and provides a good model for studying Msx involvement in defining areas of programmed cell death. Among the proposed roles for Hoxd genes is their involvement in the specification of digit identity early in development. The induction of extra digits allows us to examine whether this new morphogenetic commitment of the interdigital tissue involves changes in the domains of expression of Hoxd genes. Our results show that extra digits develop without a previous modification of the normal pattern of expression of Msx or Hoxd genes. This observation does not support the correlation between the expression of Msx genes and programmed cell death and suggests a role for these genes in maintaining the interdigital tissue in an undifferentiated state. Our results show that an increased number of digits can be formed without modifications in the pattern of expression of the 5-located Hoxd genes and suggest the existence of latent or residual digit organization mechanisms past the time when digits are normally determined, independent of Hoxd gene expression. 相似文献
993.
Maria Svetlova Ljudmila Solovjeva Grigory Stein Claude Chamberland Baldev Vig Nikolai Tomilin 《Chromosome research》1994,2(1):47-52
Recentin situ hybridization studies suggested that within the range of 0.1–1.0 Mb, human interphase chromosomes follow a random walk model (i.e. they behave as flexible polymers without major constraints). However, chromosome structure may differ in the G1, S, and G2 phases, and phase-specific constraints may be masked if the chromosome analysis does not discriminate between the phases. Therefore, using confocal microscopy, we examined the structure of S-phase chromosomes labelled with 5-iododeoxyuridine after prolonged treatment with 5-fluorodeoxyuridine. In the S-phase, labelled 0.32 µ chromosome fibres mostly appear as semi-circles with an average diameter of 0.83 ±0.03 µ. These semi-circles are joined together to form different 3D structures, and two semicircles frequently adopt s- or-like conformations involving about 2.5 µ of the chromosome contour length (L). Morphometric analysis of the S-phase fibres suggests that our data fit both the random flexible polymer model and also a model in which two constrained semi-circles are attached to each other by a flexible joint, thus eliminating constraints at long distances (L more than 2 µ). 相似文献
994.
Simultaneous pancreas-kidney transplantation is a therapeutic option for type I diabetics with end-stage renal disease. It aims to correct the uremic state, to normalize glucose hemeostasis, and to ameliorate diabetic complications. Careful donor-recipient selection and meticulous intra-operative and postoperative care will substantially impact recipient morbidity. An understanding of the technical aspects of the surgical procedure and its metabolic and immunological consequences is necessary to successfully manage a pancreas-kidney transplant recipient, many of whom are nursed in intensive care units. A successful outcome is predicted in early recognition of technical complications and aggressive management of rejection to achieve the current 1-year graft survival rates of 75% for pancreas transplants and 84% for kidney transplants. 相似文献
995.
Maria G. Cattell 《Journal of cross-cultural gerontology》1994,9(2):157-178
Among Abaluyia of Kenya relative age (seniority) structures relationships hierarchically among co-wives, siblings and females of different generations. Ambiguous equality and affectionate informality in grandmother-granddaughter relationships mute the hierarchical implications of their different age and generation statuses. This facilitates grandmothers' educational roles although, as grandmothers say, Nowadays it isn't easy to advise the young. Increased physical, cognitive and experiential distances between these generations resulted from radical changes in the female lifecourse associated with modernization and delocalization. Nevertheless, reciprocal exchanges continue. Granddaughters are also intermediaries in exchanges between older women and their adult daughters. Some grandmothers are denied the companionship and assistance of granddaughters caught in the middle of mother-in-law/daughter-in-law conflicts. Many grandmothers assume parental responsibilities as they deal with the modern problem of daughters' premarital pregnancies. All in all, these intergenerational relationships reveal both cultural persistence and the effects of social change, and continue to have instrumental and expressive value for both grandmothers and granddaughters. 相似文献
996.
997.
Sex selection may be inadvertently performed in in-vitro fertilization--embryo transfer programmes 总被引:3,自引:2,他引:1
Tarin Juan J.; Bernabeu Rafael; Baviera Amparo; Bonada Maria; Cano Antonio 《Human reproduction (Oxford, England)》1995,10(11):2992-2998
The present study aims to ascertain whether sex selection maybe inadvertently performed in human in-vitro fertilization (IVF)and embryo transfer (IVF-embryo transfer) programmes when selectingfor high quality embryos (those with the fastest cleaving ratesand/or the best morphology) at the fresh transfer cycle. Allpatients entering into the study were treated with gonadotrophinsafter pituitary suppression with gonadotrophin-releasing hormoneagonists (GnRHa) and had intrauterine embryo transfer on day2 post-insemination. These patients were retrospectively dividedinto three groups according to whether the difference in meannumber of cells between embryos transferred and all embryosavailable for transfer in a given cycle was less than (negativeselection), equal to (no selection) or greater (positive selection)than zero. In cycles resulting in singleton births, the sexratio of the resulting babies was significantly (P 0.005) shiftedtoward the female (88.8%) and to the male (90.0%) in the negativeand positive selection groups respectively. No shift in sexratio was observed in cycles resulting in multiple births. Maternalage was another independent factor affecting sex ratio at birth.Sex ratio was significantly (P 0.05) skewed in favour of males(62.7%) and females (71.4%) in women <35 and 235 years ofage respectively. Maternal age, number of embryos transferredand the event of selecting or not selecting the slowest cleavingembryos for transfer were entered automatically in a three-groupdiscriminant model for distinguishing cycles resulting in onlyboys, both boys and girls, and only girls. These data suggestthat (i) sex selection may be inadvertently performed in IVF-embryotransfer programmes when selecting for high quality embryosat the fresh transfer cycles; (ii) human endometria may be favourable,indifferent or hostile to either fast cleaving or slow cleavingembryos depending on maternal age; and (iii) naturalsex selection may be performed for social, psychological ormedical reasons. 相似文献
998.
Antonella Massari Massimo Gennarelli Elisa Menegazzo Antonio Pizzuti Vincenzo Silani Ismaele Mastrogiacomo Enzo Pagani Corrado Angelini Guglielmo Scarlato Giuseppe Novelli Bruno Dallapiccola 《Journal of neurology》1995,242(6):379-383
We have analysed the [AGC] expansion in leucocytes, muscle and sperm from 17 individuals affected by myotonic dystrophy (DM). Skeletal muscle showed a larger repeat number than leucocytes in the same patient. A similar degree of expansion was detected in differently affected muscles of a single patient. The germline mutation ( 350 repeats) was expanded in somatic cells of the progeny in all patients examined. Our results provide evidence of an early postzygotic instability of the [AGC] repeat in DM. 相似文献
999.
Athanasios Zahariou Maria Karamouti George Karagiannis Polyanthi Papaioannou 《Journal of neurology》1995,242(Z2):S61-S62
Poster Session 1
Child neurology 相似文献1000.
Background: In the past 4 years we performed operations on 90 patients who suffered from morbid obesity. Five different operative
techniques were available, vertical banded gastroplasty (VBG), silastic ring vertical gastroplasty (SRVG), gastric banding
operation, adjustable silicone gastric banding (ASGB) and biliopancreatic diversion (BPD). Methods: Two of these operations
were mainly utilized. The ASGB was done routinely. The SRVG was used particularly for patients with hiatal hernia. Only one
patient, who had a deformed pylorus, underwent the BPD. Results: Eleven patients had to be reoperated due to complications
after the first operation of gastric restriction. They were divided into three groups depending on the type of complication:
reoperation due to lack of compliance, due to technical failure, or due to other complications. In the last group we observed
three patients with band perforation into the stomach without epigastric pain. This complication has, to our knowledge, only
been described in very few cases. Conclusion: In some patients it remained difficult to reach adequate compliance, although
we kept close contact with them after the operation. We do not yet know the reasons for the band perforation observed in three
patients. 相似文献