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41.
Previously, we have shown that delta4,16-androstadien-3-one modulates psychological state, reducing negative mood and increasing positive mood (Jacob and McClintock, 2000; Jacob et al., 2001a). In order to determine whether similar musky compounds also produce these effects, we compared the effects of androstadienone to those of androstenol and muscone, measuring the psychological states of 37 participants. Androstenol and muscone were chosen because they too have a musky odor at high concentrations, while androstenol is a steroid like androstadienone and muscone is not. In a controlled laboratory setting, we conducted a double-blind, within-subject, repeated-measures experiment counterbalanced for order of presentation. Under each participant's nose, a nanomolar amount of each compound was presented, masked by clove oil to minimize perceptible olfactory differences. Participants completed a baseline psychological battery and twice again at 25-min intervals after exposure. Androstadienone's effects on psychological state were unique in comparison with those of androstenol and with muscone. Exposure through passive inhalation, rather than dermal contact, was sufficient for these effects. Although this is additional evidence that androstadienone may be a pheromone, it is yet to be determined whether humans exude concentrations into the air adequate for social communication or process this chemical information within natural social contexts.  相似文献   
42.
Currently, vitiligo lacks a validated Physician Global Assessment (PGA) for disease extent. This PGA can be used to stratify and interpret the numeric scores obtained by the Vitiligo Extent Score (VES). We investigated the interrater reliability of a 5‐point PGA scale during an international vitiligo workshop. Vitiligo experts from five different continents rated photographs of non‐segmental vitiligo patients with varying degrees of extent with the PGA score. Good interrater agreements (intraclass correlation coefficient >0.6) were observed between the raters overall and within each continent. All hypotheses to evaluate construct validity were confirmed. Median VES values per category were for limited 1.10 [IQR: 0.21–1.67], moderate 3.17 [IQR: 1.75–6.21], extensive 9.58 [IQR: 6.21–13.03] and very extensive 42.67 [IQR: 21.20–42.67]. Defined categories for vitiligo extent can be valuable for inclusion criteria and may impact future reimbursement criteria.  相似文献   
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In recent years, biopharmaceutical drug products have become hugely successful. However, they are often complex molecules that are expensive to manufacture. Commercial needs for cost-effective therapies have therefore led to the development of novel protein scaffold technologies that are increasingly being used for biopharmaceutical drug discovery. Major new scaffolds include single-domain antibodies, small modular immunopharmaceuticals, tetranectins, AdNectins, A-domain proteins, lipocalins and ankyrin repeat proteins. These scaffolds offer low-cost alternatives to classical antibody therapeutic strategies and some have shown early clinical promise. Further progress in the field will permit the commercially successful development of sophisticated protein therapeutics against complex disease targets.  相似文献   
45.

Key message

Quantitative trait loci conferring adult plant resistance to Ug99 stem rust in Thatcher wheat display complementary gene action suggesting multiple quantitative trait loci are needed for effective resistance.

Abstract

Adult plant resistance (APR) in wheat (Triticum aestivum L.) to stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is desirable because this resistance can be Pgt race non-specific. Resistance derived from cultivar Thatcher can confer high levels of APR to the virulent Pgt race TTKSK (Ug99) when combined with stem rust resistance gene Sr57 (Lr34). To identify the loci conferring APR in Thatcher, we evaluated 160 RILs derived from Thatcher crossed to susceptible cultivar McNeal for field stem rust reaction in Kenya for two seasons and in St. Paul for one season. All RILs and parents were susceptible as seedlings to race TTKSK. However, adult plant stem rust severities in Kenya varied from 5 to 80 %. Composite interval mapping identified four quantitative trait loci (QTL). Three QTL were inherited from Thatcher and one, Sr57, was inherited from McNeal. The markers closest to the QTL peaks were used in an ANOVA to determine the additive and epistatic effects. A QTL on 3BS was detected in all three environments and explained 27–35 % of the variation. The peak of this QTL was at the same location as the Sr12 seedling resistance gene effective to race SCCSC. Epistatic interactions were significant between Sr12 and QTL on chromosome arms 1AL and 2BS. Though Sr12 cosegregated with the largest effect QTL, lines with Sr12 were not always resistant. The data suggest that Sr12 or a linked gene, though not effective to race TTKSK alone, confers APR when combined with other resistance loci.  相似文献   
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The microlocalization of mast cells within specific tissue compartments is thought to be critical for the pathophysiology of many diverse diseases. This is particularly evident in asthma where they localize to the airway smooth muscle (ASM) bundles. Mast cells are recruited to the ASM by numerous chemoattractants and adhere through CADM1, but the functional consequences of this are unknown. In this study, we show that human ASM maintains human lung mast cell (HLMC) survival in vitro and induces rapid HLMC proliferation. This required cell-cell contact and occurred through a cooperative interaction between membrane-bound stem cell factor (SCF) expressed on ASM, soluble IL-6, and CADM1 expressed on HLMC. There was a physical interaction in HLMC between CADM1 and the SCF receptor (CD117), suggesting that CADM1-dependent adhesion facilitates the interaction of membrane-bound SCF with its receptor. HLMC-ASM coculture also enhanced constitutive HLMC degranulation, revealing a novel smooth muscle-driven allergen-independent mechanism of chronic mast cell activation. Targeting these interactions in asthma might offer a new strategy for the treatment of this common disease.  相似文献   
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Generating stable antibodies is an important goal in the development of antibody-based drugs. Often, thermal stability is assumed predictive of overall stability. To test this, we used different internally created antibodies and first studied changes in antibody structure as a function of pH, using the dye ANS. Comparison of the pH(50) values, the midpoint of the transition from the high-pH to the low-pH conformation, allowed us for the first time to rank antibodies based on their pH stability. Next, thermal stability was probed by heating the protein in the presence of the dye Sypro Orange. A new data analysis method allowed extraction of all three antibody unfolding transitions and showed close correspondence to values obtained by differential scanning calorimetry. T(1%) , the temperature at which 1% of the protein is unfolded, was also determined. Importantly, no correlations could be found between thermal stability and pH(50) , suggesting that to accurately quantify antibody stability, different measures of protein stability are necessary. The experimental data were further analyzed using a machine-learning approach with a trained model that allowed the prediction of biophysical stability using primary sequence alone. The pH stability predictions proved most successful and were accurate to within pH ±0.2.  相似文献   
50.
Following the degradative pathway, vesicles loaded with extracellular material, eventually, dock and fuse with lysosomes, acquiring specific membrane markers of these organelles and acid hydrolases responsible for digest their content. The lysosomal-associated membrane protein 2 (LAMP-2), the best characterized lysosomal membrane protein, is found in late stages of endosome maturation and may be used as a marker of lysosome-associated membranes. Lysosomal storage disorders (LSDs) are described by the absence or deficiency in hydrolase activity leading to substrate accumulation within lysosomal components and to the onset of several diseases. It is known that lymphocytes infected by Epstein–Barr virus (EBV) are able to form cytoplasmic vacuoles, which work as a storage compartment for lysosomal acidic hydrolases. At the present study, we validate the EBV as a transforming agent of B lymphocytes in stability studies of long-term stored samples, since the methods used to keep samples in liquid nitrogen and thaw them have all proven to be efficient in samples frozen for up to 2 years. To confirm and investigate some of the most prevalent LSDs in the South of Brazil—Pompe, Fabry and Gaucher diseases—we first measured the enzymatic activity of α-glicosidase, α-galactosidase, and β-glicosidase in those cytoplasmic-formed vacuoles and then looked to LAMP-2 immunoreactivity by employing confocal microscopy techniques.  相似文献   
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