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1.
Y Eshel  Y Sarne  A D Korczyn 《Life sciences》1983,32(10):1053-1056
Administration of somatostatin intracerebroventricularly to mice produced a dose-dependent mydriasis, whereas intravenous injections were ineffective. Naloxone could prevent or abolish this effect. It is suggested that somatostatin either directly excites opiate receptors or activates endopioid pathways involved in the regulation of pupillary size.  相似文献   
2.
We report here the successful selective cultivation of murine thymic mesenchymal reticular cells (MTMC) and murine thymic epithelial cells (MTEC) grown on extracellular matrix in the presence of defined medium. The selective growth of these two cell types was based on 1) conditions of tissue disruption and 2) differential growth requirements. Both cell types were dependent on transferrin, high density lipoproteins, insulin, hydrocortisone, and epidermal growth factor, whereas MTMC was dependent also on selenium and 3,5,3'-triiodothyronine. The elimination of single factors or extracellular matrix resulted in specific and different changes in the growth pattern of each cell subpopulation. Cells of both types exhibited the ultrastructural features of high metabolic activity. The epithelial nature of MTEC cultures was defined by bundles of tonofilaments and desmosomes and by positive staining to keratins and negative to vimentin. In addition MTEC were positively stained with mAb to thymic medullary epithelial cells and by Ulex europeus agglutinin, and were able to form Hassall's corpuscles, suggesting their medullary origin. MTEC were also H-2 and Ia positive. In contrast MTMC were positive for vimentin and periodic acid-Schiff, low positive for H-2, and negative for keratin and Ia. Both cells did not contain nonspecific esterase, nor did they phagocytize latex beads. With the use of all these criteria we classified MTEC as epithelial cells from the medullary compartment of the thymus and MTMC as reticular cells of mesenchymal origin.  相似文献   
3.
Intrinsic biological resemblance between two types is measured in terms of a correlation between their fitnesses under various possible environmental conditions. A tendency toward dominance is defined as the intrinsic biological resemblance between homozygote and heterozygote. The effect of a tendency toward dominance on the à priori survival probability of a mutant gene is studied when the fitnesses of the mutated forms are given only by their distributions. Close intrinsic resemblance between homozygous and heterozygous forms of a new mutant gene is shown to substantially increase the à priori survival probability of this gene. A probabilistic effect of selection is, thus, shown to statistically favor dominant or near dominant mutant genes to start with.This probabilistic effect is suggested as complementary to the Fisherian process of selection on the heterozygote modifiers, taking place at further stages of the progress of a mutant gene.  相似文献   
4.
5.
The arthropod cuticle acts as a physiochemical barrier protecting the organism from pathogens' entry. Entomopathogenic fungi actively penetrate the cuticles of arthropod hosts and are therefore directly affected by cuticle composition. Previously we have observed that Metarhizium spp. developing on resistant ticks ultimately die without penetrating tick's cuticle, suggesting that the cuticles of resistant ticks have antifungal compounds. In the present study, lipids and water-soluble cuticular components were extracted from engorged female tick cuticles, of one susceptible and one resistant tick species to Metarhizium spp. While conidia exposed to lipids from the susceptible tick, Rhipicephalus annulatus, germinated and differentiated into appressorium, conidia exposed to lipids from the resistant tick, Hyalomma excavatum, were inhibited. Soluble cuticular component extracts from both susceptible and resistant ticks stimulated conidial germination but not appressorium differentiation. A comparative analysis of the fatty acid profile in lipid extract of each tick exhibited similar compositions, but the relative abundance of C16:0, C18:0, C18:1ω9C and C20:0 was 2–5 times higher in the extracts from resistant ticks. All of these fatty acids inhibited conidial germination in vitro at 1% and 0.1% w/v concentration, but C20:0 stimulated appressorium differentiation at low concentration. This is the first report demonstrating a possible link between the presence of antifungal compounds in a specific concentration in tick cuticle and tick resistance to infection.  相似文献   
6.

Background

Pain from bone metastases of breast cancer origin is treated with localized radiation. Modulating doses and schedules has shown little efficacy in improving results. Given the synergistic therapeutic effect reported for combined systemic chemotherapy with local radiation in anal, rectal, and head and neck malignancies, we sought to evaluate the tolerability and efficacy of combined capecitabine and radiation for palliation of pain due to bone metastases from breast cancer.

Methodology/Principal Findings

Twenty-nine women with painful bone metastases from breast cancer were treated with external beam radiation in 10 fractions of 3 Gy, 5 fractions a week for 2 consecutive weeks. Oral capecitabine 700 mg/m2 twice daily was administered throughout radiation therapy. Rates of complete response, defined as a score of 0 on a 10-point pain scale and no increase in analgesic consumption, were 14% at 1 week, 38% at 2 weeks, 52% at 4 weeks, 52% at 8 weeks, and 48% at 12 weeks. Corresponding rates of partial response, defined as a reduction of at least 2 points in pain score without an increase in analgesics consumption, were 31%, 38%, 28%, 34% and 38%. The overall response rate (complete and partial) at 12 weeks was 86%. Side effects were of mild intensity (grade I or II) and included nausea (38% of patients), weakness (24%), diarrhea (24%), mucositis (10%), and hand and foot syndrome (7%).

Conclusions/Significance

External beam radiation with concurrent capecitabine is safe and tolerable for the treatment of pain from bone metastases of breast cancer origin. The overall and complete response rates in our study are unusually high compared to those reported for radiation alone. Further evaluation of this approach, in a randomized study, is warranted.

Trial Registration

ClinicalTrials.gov NCT01784393NCT01784393  相似文献   
7.
Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors’ long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI), an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors—the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress.  相似文献   
8.
Despite the progress in developing personal combat-protective gear, eye and brain injuries are still widely common and carry fatal or long-term repercussions. The complex nature of the cranial tissues suggests that simple methods (e.g. crash-dummies) for testing the effectiveness of personal protective gear against non-penetrating impacts are both expensive and ineffective, and there are ethical issues in using animal or cadavers. The present work presents a versatile testing framework for quantitatively evaluating protective performances of head and eye combat-protective gear, against non-penetrating impacts. The biomimetic finite element (FE) head model that was developed provides realistic representation of cranial structure and tissue properties. Simulated crash impact results were validated against a former cadaveric study and by using a crash-phantom developed in our lab. The model was then fitted with various helmet and goggle designs onto which a non-penetrating ballistic impact was applied. Example data show that reduction of the elastic and shear moduli by 30% and 80% respectively of the helmet outer Kevlar-29 layer, lowered intracranial pressures by 20%. Our modeling suggests that the level of stresses that develop in brain tissues, which ultimately cause the brain damage, cannot be predicted solely by the properties of the helmet/goggle materials. We further found that a reduced contact area between goggles and face is a key factor in reducing the mechanical loads transmitted to the optic nerve and eye balls following an impact. Overall, this work demonstrates the simplicity, flexibility and usefulness for development, evaluation, and testing of combat-protective equipment using computational modeling.
  • Highlights
  • A finite element head model was developed for testing head gear.

  • Reduced helmet’s outer layer elastic and shear moduli lowered intracranial stresses.

  • Gear material properties could not fully predict impact-related stress in the brain.

  • Reduced goggles-face contact lowered transmitted loads to the optic nerve and eyes.

  相似文献   
9.
Respiratory syncytial virus (RSV) can cause bronchiolitis and viral pneumonia in young children and the elderly. Lack of vaccines and recurrence of RSV infection indicate the difficulty in eliciting protective memory immune responses. Tissue resident memory T cells (TRM) can confer protection from pathogen re-infection and, in human experimental RSV infection, the presence of lung CD8+ TRM cells correlates with a better outcome. However, the requirements for generating and maintaining lung TRM cells during RSV infection are not fully understood. Here, we use mouse models to assess the impact of innate immune response determinants in the generation and subsequent expansion of the TRM cell pool during RSV infection. We show that CD8+ TRM cells expand independently from systemic CD8+ T cells after RSV re-infection. Re-infected MAVS and MyD88/TRIF deficient mice, lacking key components involved in innate immune recognition of RSV and induction of type I interferons (IFN-α/β), display impaired expansion of CD8+ TRM cells and reduction in antigen specific production of granzyme B and IFN-γ. IFN-α treatment of MAVS deficient mice during primary RSV infection restored TRM cell expansion upon re-challenge but failed to recover TRM cell functionality. Our data reveal how innate immunity, including the axis controlling type I IFN induction, instructs and regulates CD8+ TRM cell responses to RSV infection, suggesting possible mechanisms for therapeutic intervention.  相似文献   
10.
Pepper plants containing the dominant A gene accumulate anthocyanin pigments in the foliage, flower and immature fruit. We previously mapped A to pepper chromosome 10 in the F2 progeny of a cross between 5226 (purple-fruited) and PI 159234 (green-fruited) to a region that corresponds, in tomato, to the location of Petunia anthocyanin 2 (An2), a regulator of anthocyanin biosynthesis. This suggested that A encodes a homologue of Petunia An2. Using the sequences of An2 and a corresponding tomato expressed sequence tag, we isolated a pepper cDNA orthologous to An2 that cosegregated with A. We subsequently determined the expression of A by Northern analysis, using RNA extracted from fruits, flowers and leaves of 5226 and PI 159234. In 5226, expression was detected in all stages of fruit development and in both flower and leaf. In contrast, A was not expressed in the sampled tissues in PI 159234. Genomic sequence comparison of A between green- and purple-fruited genotypes revealed no differences in the coding region, indicating that the lack of expression of A in the green genotypes can be attributed to variation in the promoter region. By analyzing the expression of the structural genes in the anthocyanin biosynthetic pathway in 5226 and PI 159234, it was determined that, similar to Petunia, the early genes in the pathway are regulated independently of A, while expression of the late genes is A-dependent.Communicated by R. Hagemann  相似文献   
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