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排序方式: 共有1324条查询结果,搜索用时 31 毫秒
1.
Needle-localized breast biopsy: why do we fail? 总被引:10,自引:0,他引:10
2.
J. Duteil FA Rambert AM Pointeau P. Mangiameli and E. Assous 《Fundamental & clinical pharmacology》1991,5(8):695-708
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice. 相似文献
3.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
4.
B. J. Oddens H. Th. Arnolds M. G. M. van Maris H. W. van Lunsen 《Advances in Contraception》1994,10(3):167-174
Data from an ongoing series of surveys on contraceptive use in the Netherlands were analyzed with respect to the percentages of oral contraceptive (OC) users who annually started use, discontinued use or switched to another OC type. The surveys had been conducted between 1990 and 1993 among samples of women aged 15–49 who belonged to a survey panel. Response rates of the surveys were 89–90% and the sample sizes ranged from 4560 to 4621 women. The assessed OC use rates reflected those of the Dutch population reasonably well. Of all respondents who had used OCs during the 12 months prior to the surveys, 12–15% discontinued use within this period, mainly in order to get pregnant, 12–16% were starters and 9–14% switchers. Of all starters 37% switched to another OC type within the first 12 months after starting. Switching was mainly related to the experience of perceived side-effects and wishes for better cycle control. The results highlighted the relevance of closely monitoring the individual woman's satisfaction with her OC. Since OC use appeared in many cases to be characterized by an active seeking for the most acceptable OC type, a wide range of OC types available and the development and introduction of new types is highly relevant for tailoring contraceptive use to individual needs.
Resumen Se analizaron los datos de una serie de estudios que se están efectuando con respecto al uso de anticonceptivos en los Países Bajos a fin de determinar los porcentajes de usuarias de anticonceptivos orales (AO) que habían comenzado a utilizar, dejado de utilizar o pasado a otro tipo de AO, anualmente. Los estudios se habían efectuado entre 1990 y 1993 con muestras de mujeres de 15 a 49 años que formaban parte de un panel de estudio. Las tasas de respuesta de los estudios fueron del 89–90% y los tamaños de las muestras estuvieron comprendidos entre 4.560 y 4.621 mujeres. Las tasas de uso de AO evaluadas reflejaron las de la población holandesa razonablemente bien. De todas las encuestadas que habían utilizado AO durante los 12 meses anteriores a los estudios, el 12–15% dejó de utilizarlos dentro de este período, principalmente a fin de quedar embarazada, el 12–16% recién comenzaba a utilizarlos y el 9–14% había cambiado a otro tipo de AO. De todas las que recién comenzaban a utilizarlos, el 37% pasó a otro tipo de AO dentro de los 12 meses de iniciado su uso. El cambio se relacionaba principalmente con la experiencia de los efectos secundarios percibidos y el deseo de un mejor control del ciclo. Los resultados destacaron la importancia de una monitorización estrecha de la satisfacción individual de la usuaria con respecto a su AO. Dado que la utilización de AO pareció en muchos casos caracterizarse por la búsqueda activa del tipo más aceptable de AO, una amplia gama disponible de tipos de AO y el desarrollo y la introducción de nuevos tipos son aspectos que revisten gran importancia en la adaptación del uso de anticonceptivos a las necesidades individuales.
Resumé Les données provenant d'une série en cours d'enquêtes sur l'utilisation des contraceptifs aux Pays-Bas ont été analysées du point de vue des pourcentages des utilisatrices de contraceptifs oraux (CO) qui ont, pendant chaque année, commencé à les utiliser, les ont abandonnés ou sont passées à un autre type de CO. Les enquêtes ont été menées entre 1990 et 1993 parmi des échantillons de femmes âgées de 15 à 49 ans qui constituaient la population étudiée. Les pourcentages de réponses aux enquêtes se sont élevés à 89–90% pour un échantillonnage allant de 4560 à 4621 femmes. Les pourcentages d'utilisation de CO évalués reflétaient assez bien ceux de la population néerlandaise en général. Parmi toutes ces femmes qui avaient utilisé les CO durant les 12 mois précédant l'enquête, 12–15% avaient cessé au cours de cette même période, en général pour avoir un enfant, 12–16% avaient commencé à les utiliser et 9–14% avaient changé de type de CO. Parmi toutes celles qui avaient commencé, 37% ont changé de produit au cours des 12 premiers mois. Le choix d'un autre type de CO étail essentiellement lié à des effets secondaires ressentis et au désir de mieux régler le cycle menstruel. Les résultats mettent en évidence combien il est important de suivre de près dans quelle mesure les femmes sont individuellement satisfaites du CO qu'elles adoptent. Etand donné que l'utilisation des Co semble, dans beaucoup ce cas, être caractérisée par une recherche active du type de CO le plus acceptable, le choix possible dans toute une gamme de CO, ainsi que la mise au point et l'introduction de nouveaux types, permettent remarquablement bien d'adapter l'utilisation des contraceptifs aux besoins individuels.相似文献
5.
科室主任管理职能与基本素质探讨 总被引:11,自引:3,他引:8
人力资源在管理中发挥着重要作用,其中,科室主任作为医院人力资源的重要组成部分,在医院惯性运行和可持续发展中扮演着重要角色。因此,科室主任因其技术和管理双重职责所具备的管理职能、基本素质和领导艺术在日常工作中显得尤为关键。 相似文献
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9.
Segmental duplicons (>1 kb) of high sequence similarity (>90%) covering >5% of the human genome are characterized by complex sequence variation. Apart from a few well-characterized regions (MHC, β-globin), the diversity and linkage disequilibrium (LD) patterns of duplicons and the role of gene conversion in shaping them have been poorly studied. To shed light on these issues, we have re-sequenced the human Luteinizing Hormone/Chorionic Gonadotropin β (LHB/CGB) cluster (19q13.32) of three population samples (Estonians, Mandenka, and Han). The LHB/CGB cluster consists of seven duplicated genes critical in human reproduction. In the LHB/CGB region, high sequence diversity, concentration of gene-conversion acceptor sites, and strong LD colocalize with peripheral genes, whereas central loci are characterized by lower variation, gene-conversion donor activity, and breakdown of LD between close markers. The data highlight an important role of gene conversion in spreading polymorphisms among duplicon copies and generating LD around them. The directionality of gene-conversion events seems to be determined by the localization of a predicted recombination “hotspot” and “warm spot” in the vicinity of the most active acceptor genes at the periphery of the cluster. The data suggest that enriched crossover activity in direct and inverted segmental repeats is in accordance with the formation of palindromic secondary structures promoting double-strand breaks rather than fixed DNA sequence motifs. Also, this first detailed coverage of sequence diversity and structure of the LHB/CGB gene cluster will pave the way for studying the identified polymorphisms as well as potential genomic rearrangements in association with an individual's reproductive success. 相似文献
10.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献