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151.
Touch preparations of human placenta yield cells retaining antigenic reactivity to immunoperoxidase stains for alpha and beta chains of human chorionic gonadotropin, placental lactogen, and pregnancy-specific beta glycoprotein. This method is a rapid and simple alternative to conventional frozen and paraffin-embedded sections for detection of placental peptides.  相似文献   
152.
Small-sample bias of point estimators of the odds ratio from matched sets   总被引:2,自引:0,他引:2  
N P Jewell 《Biometrics》1984,40(2):421-435
The bias of several point estimators of the odds ratio arising from matched-pair data is investigated for small samples. Simple alternatives to the traditional maximum likelihood estimator are suggested, on both the original scale and the logarithm scale. In each case the suggested estimators possess a superior performance in terms of mean square error. Generalizations are given for 1:R matched data sets.  相似文献   
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A patient management questionnaire was written to assess the range of advice being offered to parents on common paediatric problems. It was sent to hospital doctors, clinical medical officers, health visitors, and general practitioner trainers and trainees. In the 95 completed questionnaires just over half the items elicited conflicting advice, and some differences between different professional groups could be identified. It is suggested that such conflicts are potentially damaging to relationships between patients and health care professionals and that there are ways to avoid conflict.  相似文献   
156.
The nucleolar regions on chromosomes 1B and 6B of Triticum aestivum L. cv Chinese Spring wheat can reliably be observed after careful control of the Giemsa N-banding technique. Identification of rye (Secale cereaie) chromosomes using N-banding is demonstrated and compared to a simple C-banding method. The N-banding in rye chromosomes and the nucleolar sites on IB and 6B of wheat differ from the normal N-banding sites of wheat chromosomes. Further, the banding of these nucleolar regions and of the rye chromosomes does not reappear in preparations that have been retreated with hot acid buffer. These differences provide evidence for at least two types of chromatin that stain darkly (positively) using N-banding. The critical procedures in the N-banding technique and the use of alternatives to 1 M NaH2PO4 buffer are discussed along with the possible basis of N-band formation.  相似文献   
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L. D. Jewell  A. Medline  N. M. Medline 《CMAJ》1971,105(7):711-714,717
Clinical and pathological data from four cases of fatal non-cirrhotic alcoholic hepatitis are presented. The patients were relatively young but had a long history of excessive alcohol intake, and the disease had an acute onset which progressed inexorably to death in hepatic and renal failure.At autopsy the livers were enlarged but non-cirrhotic. The important histological criteria for the diagnosis of alcoholic hepatitis are a panlobular polymorphonuclear inflammatory cell infiltrate, the presence of Mallory material (alcoholic hyaline) and fine fibrosis surrounding small groups of liver cells. The latter finding may be more marked in the centrolobular zone and result in the picture of central hyaline sclerosis.  相似文献   
159.
Glucose-induced insulin exocytosis is coupled to associations between F-actin and SNARE proteins, although the nature and function of these interactions remains unknown. Toward this end we show here that both Syntaxin 1A and Syntaxin 4 associated with F-actin in MIN6 cells and that each interaction was rapidly and transiently diminished by stimulation of cells with d-glucose. Of the two isoforms, only Syntaxin 4 was capable of interacting directly with F-actin in an in vitro sedimentation assay, conferred by the N-terminal 39-112 residues of Syntaxin 4. The 39-112 fragment was capable of selective competitive inhibitory action, disrupting endogenous F-actin-Syntaxin 4 binding in MIN6 cells. Disruption of F-actin-Syntaxin 4 binding correlated with enhanced glucose-stimulated insulin secretion, mediated by increased granule accumulation at the plasma membrane and increased Syntaxin 4 accessibility under basal conditions. However, no increase in basal level Syntaxin 4-VAMP2 association occurred with either latrunculin treatment or expression of the 39-112 fragment. Taken together, these data disclose a new underlying mechanism by which F-actin negatively regulates exocytosis via binding and blocking Syntaxin 4 accessibility, but they also reveal the existence of additional signals and/or steps required to trigger the subsequent docking and fusion steps of exocytosis.  相似文献   
160.
Summary .   We consider methods for estimating the effect of a covariate on a disease onset distribution when the observed data structure consists of right-censored data on diagnosis times and current status data on onset times amongst individuals who have not yet been diagnosed. Dunson and Baird (2001, Biometrics 57, 306–403) approached this problem using maximum likelihood, under the assumption that the ratio of the diagnosis and onset distributions is monotonic nondecreasing. As an alternative, we propose a two-step estimator, an extension of the approach of van der Laan, Jewell, and Petersen (1997, Biometrika 84, 539–554) in the single sample setting, which is computationally much simpler and requires no assumptions on this ratio. A simulation study is performed comparing estimates obtained from these two approaches, as well as that from a standard current status analysis that ignores diagnosis data. Results indicate that the Dunson and Baird estimator outperforms the two-step estimator when the monotonicity assumption holds, but the reverse is true when the assumption fails. The simple current status estimator loses only a small amount of precision in comparison to the two-step procedure but requires monitoring time information for all individuals. In the data that motivated this work, a study of uterine fibroids and chemical exposure to dioxin, the monotonicity assumption is seen to fail. Here, the two-step and current status estimators both show no significant association between the level of dioxin exposure and the hazard for onset of uterine fibroids; the two-step estimator of the relative hazard associated with increasing levels of exposure has the least estimated variance amongst the three estimators considered.  相似文献   
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