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31.
Patients with clinical features of MEN 1 without mutations in the menin gene fulfill the criteria of MEN1-like syndrome. Primary hyperparathyroidism (PHP) is the most frequent clinical finding in both syndromes and is usually treated by surgery. However, PHP has been reported to respond to somatostatin analogues (SSA) in MEN 1 patients. 7 patients with PHP in the context of MEN 1-like syndrome (and absence of mutations in the menin gene) were enrolled in the study and treated with SSA for 6 months for the non-PHP disease before parathyroidectomy. Serum ionized calcium, phosphorus, and PTH concentrations, and 24-h urinary calcium and phosphorus excretion were measured before and after SSA therapy. Mean serum ionized calcium, phosphorus, and PTH concentrations did not significantly change after a 6-month course with SSA. SSA scintigraphy did not reveal uptake in the neck region corresponding to the parathyroid adenoma identified at surgery and confirmed at histology. However, immunohistochemistry revealed SS-type 2A receptor in parathyroid tissue samples of 6 out of 7 patients. SSA therapy does not affect calcium-phosphorus metabolism in patients with MEN 1-like syndrome, suggesting that the drug has no role in controlling PHP in these subset of patients.  相似文献   
32.
Sensory ecology, receiver biases and sexual selection   总被引:2,自引:0,他引:2  
During courtship, signals are sent between the sexes, and received signals contain information that forms the basis of decision making. Much is known about signal content, but less is known about signal design-what makes signals work efficiently? A consideration of design not only gives new insights into the evolution of signals (including novelty), but also allows the development of specific and testable predictions about the direction of evolution. Recently there has been increased interest in signal design, but this has resulted in some apparently divergent views in the literature.  相似文献   
33.
At present, the clinical and pathological analysis used in the diagnosis of papillary thyroid cancer (PTC) are insufficient to discern tumor behavior, and new diagnostic and prognostic markers need to be identified. In this study, we performed a comparative proteome analysis to examine the global changes of fine needle aspiration fluid (FNA) protein patterns of two variants of malignant PTC (classical variant PTC (cPTC) and tall cell variant PTC (TCV)) with respect to the controls. Changes in protein expression were identified using two-dimensional electrophoresis (2DE) and peptide mass fingerprinting via MALDI-TOF mass spectrometry (MS), as well as Western blot analysis. A statistical significant up-regulation of 17 protein spots in cPTC and/or TCV with respect to controls was demonstrated. These proteins included transthyretin precursor (TTR), ferritin light chain (FLC), proteasome activator complex subunit 1 and 2, alpha-1-antitrypsin precursor, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), lactate dehydrogenase chain B (LDH-B), apolipoprotein A1 precursor (Apo-A1), annexin A1, DJ-1 protein and cofilin-1. In addition, 12 protein spots were found exclusively in cPTC and three exclusively in TCV. These latter proteins (ferritin heavy chain (FHC), peroxiredoxin 1 (PRX1) and 6-phosphogluconate dehydrogenase (6-PDGH)) correspond to stress response proteins and, until now, had not been described in thyroid tumors. These findings illustrate the potential use of FNA proteomics to identify protein changes associated with thyroid cancer and to advance potential protein biomarkers in the diagnostic classification of the disease.  相似文献   
34.

Background  

Tat is being tested as a component of HIV vaccines. Tat activity has been mainly investigated on cells of lymphoid/hematopoietic lineages. HIV-1, however, is known to infect many different cells of both solid organs and mucosal surfaces. The activity of two-exon (aa 1–101) and synthetic (aa 1–86) Tat was studied on mammary and amniotic epithelial cells cultured under low serum conditions.  相似文献   
35.
We performed artificial selection on the visual system in guppies (Poecilia reticulata), using the optomotor reaction threshold as the selection criterion. Two lines were selected for increased sensitivity to blue light, two were selected for increased sensitivity to red light, and two were unselected controls. There was significant response to selection in all four selected lines and significant heritability for sensitivity. An examination of the spectral sensitivity function showed that the form of the response differed between the red and blue lines and among the red lines. Such divergence is likely because there are many different mechanisms allowing response to selection for spectral sensitivity. Diverse mechanisms allow a divergent response by different populations to the same selective pressures. Such a mechanism can promote diversity in vision and visual signals, and any multicomponent system where different components can respond to the same selective regime.  相似文献   
36.
Behavioural plasticity is a form of reversible phenotypic plasticity in which a genotype can express different behavioural phenotypes under different environmental conditions. Though an interest in among-individual differences in behavioural plasticity has flourished in recent decades, few studies have considered the effects of intrinsic factors, such as life-history or morphological traits, in tandem with extrinsic factors, such as presence of conspecifics in different social contexts, on predator-induced behavioural plasticity. Here, we present a study conducted with female green swordtail fishes, Xiphophorus hellerii, designed to assess the effects of age-at-maturation and body size on the expression of predator-induced behavioural plasticity in two social contexts: (a) female-only (two females) and (b) female-and-male (two females and a male). We further examined the extent to which individual expression of behavioural plasticity is consistent across these two social contexts. We found that in the presence of a predator, focal females were more timid in response to the stimulus and more tolerant of the non-focal female, and small females expressed this change from bold/less tolerant to timid/more tolerant to a greater degree than large females, regardless of age-at-maturation. However, individuals were not consistent in the degree or direction of plasticity expressed in the behaviours of interest between the female-only and the female-and-male context. Here, we show that within- and among-individual differences in behavioural expression are common but inconsistent. How intrinsic and extrinsic factors independently or together drive expression of plasticity in antipredator and agonistic behaviours is varied and warrants further study.  相似文献   
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