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111.
Globulins (GLB) are storage proteins that accumulate to high levels during zygotic embryo development of Zea mays L. We visualized the distribution of GLB during zygotic embryo development by immunolabelling of polyethylene glycol sections with a GLB-specific antiserum and a fluorescent secondary antibody. In sections of embryos at 10 days after pollimation (DAP), GLB were detected in the scutellar node only. Sections of embryos of 17 DAP showed, besides the presence of GLB in the scutellar node, the presence of a low amount of GLB in the coleoptile and the leaf primordia. In 30-DAP embryos GLB were localized in the root, the coleorhiza, the leaf primordia, the coleoptile and in all cells of the scutellum with the exception of the epidermis and the pro-vascular tissues. The subcellular location of GLB was visualized by immunolabelling of ultrathin sections with anti-GLB and a gold-conjugated secondary antibody. Scutellum cells and root cortex cells of 30-DAP embryos were packed with protein storage vacuoles (PSV), which differed in electron density. GLB were either evenly distributed throughout the PSV or were localized in electron-dense inclusions within the PSV. SDS-PAGE and immunoblot analysis of total protein extracts indicated the presence of a low amount of the GLB1 processing intermediate proGLB1'in globular as well as mature somatic embryos. After maturation on an ABA-containing medium, somatic embryos showed the additional presence of the next GLB1 processing intermediate GLB1. By immuno-electron microscopy it was possible to localize GLB in globular deposits in PSV in scutellum cells of these somatic embryos.  相似文献   
112.
ObjectiveIn the Netherlands, an increasing number of emergency departments (EDs) and general practitioner cooperatives collaborate by creating one Emergency-Care-Access-Point (ECAP). This has resulted in fewer patients at ECAP EDs. The objective of this study was to explore differences in patient characteristics, presented complaints and ED discharge diagnoses between EDs with an ECAP and EDs without an ECAP.MethodsA retrospective observational study was performed with 1800 consecutive patient records sampled from six EDs spread over the Netherlands in 2013. We extracted data on time and date of presentation, sex, age, presenting complaint, discharge diagnosis, origin and follow up.ResultsAt ECAP EDs, the mean age was 47.8 years (95%CI 46.1-49.4) compared to 41.3 (95%CI 39.7-42.9). Compared to non-ECAP EDs, more patients were referred by medical professionals (74.7% versus 46.8%), more patients received hospital admission (45.2% versus 29.0%) and fewer patients received GP follow-up (4.1% versus 16.9%). There was no significant difference in presenting complaints between ECAP and non-ECAP EDs. Most prevalent complaints were trauma (25.7% versus 29.7%), abdominal pain (12.1% versus 10.9%) and general symptoms (7.8% versus 4.8%). The most prevalent ED diagnoses significantly differed with fractures and dislocations (10.8%), sprains and strains (10.4%) and respiratory infections (6.8%) at ECAP EDs versus fractures and dislocations (10.7%), wounds (9.3%) and sprains and strains (8.9%) at non-ECAP EDs.ConclusionCompared to non-ECAP EDs, patients at ECAP EDs were older, medical professionals referred more patients and more patients received a hospital admission. We found some small differences in discharge diagnoses between ECAP EDs compared to non-ECAP EDs, but no difference in presented complaints.  相似文献   
113.
Dendritic cell (DC) and natural killer (NK) cell interactions are important for the regulation of innate and adaptive immunity, but their relevance during early pregnancy remains elusive. Using two different strategies to manipulate the frequency of NK cells and DC during gestation, we investigated their relative impact on the decidualization process and on angiogenic responses that characterize murine implantation. Manipulation of the frequency of NK cells, DC or both lead to a defective decidual response characterized by decreased proliferation and differentiation of stromal cells. Whereas no detrimental effects were evident upon expansion of DC, NK cell ablation in such expanded DC mice severely compromised decidual development and led to early pregnancy loss. Pregnancy failure in these mice was associated with an unbalanced production of anti-angiogenic signals and most notably, with increased expression of genes related to inflammation and immunogenic activation of DC. Thus, NK cells appear to play an important role counteracting potential anomalies raised by DC expansion and overactivity in the decidua, becoming critical for normal pregnancy progression.  相似文献   
114.
Animal personalities range from individuals that are shy, cautious, and easily stressed (a “reactive” personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a “proactive” personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large‐ and small‐brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large‐brained animals were faster to habituate to, and more exploratory in, open field tests. Large‐brained females were also bolder. Second, large‐brained animals excreted less cortisol in a stressful situation (confinement). Third, large‐brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large‐brained lines. Overall, the results point toward a more proactive personality type in large‐brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness‐related aspects of ecology such as dispersal and niche exploration.  相似文献   
115.

Background

Sputum induction is a non-invasive method for obtaining measurements of inflammation in the airways. Whether spontaneously sampled sputum can be a valid surrogate is unknown. The aim of this study was to compare levels of six inflammatory markers in sputum pairs consisting of induced and spontaneous sputum sampled on the same consultation either in a stable state or during exacerbations of chronic obstructive pulmonary disease (COPD).

Methods

433 COPD patients aged 40–76, Global initiative for chronic Obstructive Lung Disease (GOLD) stage II-IV were enrolled in 2006/07 and followed every six months for three years. 356 patients were followed for potential exacerbations. Interleukin-6, interleukin-8, interleukin-18, interferon gamma-inducible protein-10, monokine induced by gamma interferon and tumor necrosis factor-alpha (IL-6, IL-8, IL-18, IP-10, MIG and TNF-α) were measured by bead based multiplex immunoassay in 60 paired sputum samples from 45 patients. Albumin was measured by enzyme immunoassay, for concentration correction. Culturing for bacterial growth was performed on 24 samples. Bland-Altman plots were used to assess agreement. The paired non-parametric Wilcoxon signed-rank test, the non-parametric Spearman’s rank correlation test and Kruskal-Wallis test were used for statistical analyses. For all analyses, a p-value < 0.05 was considered significant.

Results

Agreement between the two measurements was generally low for all six markers. TNF-α was significantly higher in spontaneous sputum at exacerbations (p = 0.002) and trending higher at the steady state (p = 0.06). Correlation coefficients between the levels of markers in induced and spontaneous sputum varied between 0.58 (IL-18) to 0.83 (IP-10). In spontaneous sputum IL-18 and MIG were higher in ex-smokers (p < 0.05). The levels of all markers were higher in GOLD stage III & IV except for IL-6 in spontaneous sputum and IL-18 in induced sputum, compared with GOLD stage II, although not statistically significant. In spontaneous sputum the levels of IL-6 were significantly higher if Haemophilus influenzae (HI) was not cultured.

Conclusion

We observed a low agreement and significant differences in inflammatory markers between induced and spontaneous sputum, both at steady state and exacerbations. We recommend considering sampling method when reporting on inflammatory markers in sputum.  相似文献   
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Previous studies have established effects of exercise training on arterial wall thickness, remodeling, and function in humans, but the extent to which these changes are locally or systemically mediated is unclear. We examined the brachial arteries of the dominant (D) and nondominant (ND) upper limbs of elite racquet sportsmen and compared them to those of matched healthy inactive controls. Carotid and superficial femoral artery responses were also assessed in both groups. High-resolution duplex ultrasound was used to examine resting diameter, wall thickness, peak diameter, and blood flow. We found larger resting arterial diameter in the preferred arm of the athletes (4.9 ± 0.5 mm) relative to their nonpreferred arm (4.3 ± 0.4 mm, P < 0.05) and both arms of control subjects (D: 4.1 ± 0.4 mm; ND: 4.0 ± 0.4, P < 0.05). Similar limb-specific differences were also evident in brachial artery dilator capacity (5.5 ± 0.5 vs. 4.8 ± 0.4, 4.8 ± 0.6, and 4.8 ± 0.6 mm, respectively; P < 0.05) following glyceryl trinitrate administration and peak blood flow (1,118 ± 326 vs. 732 ± 320, 737 ± 219, and 698 ± 174 ml/min, respectively; P < 0.05) following ischemic handgrip exercise. In contrast, athletes demonstrated consistently lower wall thickness in carotid (509 ± 55 μm), brachial (D: 239 ± 100 μm; ND: 234 ± 133 μm), and femoral (D: 479 ± 38 μm; ND: 479 ± 42 μm) arteries compared with control subjects (carotid: 618 ± 74 μm; brachial D: 516 ± 100 μm; ND: 539 ± 129 μm; femoral D: 634 ± 155 μm; ND: 589 ± 112 μm; all P < 0.05 vs. athletes), with no differences between the limbs of either group. These data suggest that localized effects of exercise are evident in the remodeling of arterial size, whereas arterial wall thickness appears to be affected by systemic factors.  相似文献   
119.
Physical inactivity is associated with an increase in cardiovascular risk that cannot be fully explained by traditional or novel risk factors. Inactivity is also associated with changes in hemodynamic stimuli, which exert direct effects on the vasculature leading to remodeling and a proatherogenic phenotype. In this review, we synthesize and summarize in vivo evidence relating to the impact of local and systemic models of physical inactivity on conduit arteries, resistance vessels, and the microcirculation in humans. Taken together, the literature suggests that a rapid inward structural remodeling of vessels occurs in response to physical inactivity. The magnitude of this response is dependent on the "dose" of inactivity. Moreover, changes in vascular function are found at resistance and microvessel levels in humans. In conduit arteries, a strong interaction between vascular function and structure is present, which results in conflicting data regarding the impact of inactivity on conduit artery function. While much of the cardioprotective effect of exercise is related to the nitric oxide pathway, deconditioning may primarily be associated with activation of vasoconstrictor pathways. The effects of deconditioning on the vasculature are therefore not simply the opposite of those in response to exercise training. Given the importance of sedentary behavior, future studies should provide further insight into the impact of inactivity on the vasculature and other (novel) markers of vascular health. Moreover, studies should examine the role of (hemodynamic) stimuli that underlie the characteristic vascular adaptations during deconditioning. Our review concludes with some suggestions for future research directions.  相似文献   
120.

The effect of repair techniques on the biomechanics of the aorta is poorly understood, resulting in significant levels of postoperative complications for patients worldwide. This study presents a computational analysis of the influence of Nitinol-based devices on the biomechanical performance of a healthy patient-specific human aorta. Simulations reveal that Nitinol stent-grafts stretch the artery wall so that collagen is stretched to a straightened high-stiffness configuration. The high-compliance regime (HCR) associated with low diastolic lumen pressure is eliminated, and the artery operates in a low-compliance regime (LCR) throughout the entire cardiac cycle. The slope of the lumen pressure–area curve for the LCR post-implantation is almost identical to that of the native vessel during systole. This negligible change from the native LCR slope occurs because the stent-graft increases its diameter from the crimped configuration during deployment so that it reaches a low-stiffness unloading plateau. The effective radial stiffness of the implant along this unloading plateau is negligible compared to the stiffness of the artery wall. Provided the Nitinol device unloads sufficiently during deployment to the unloading plateau, the degree of oversizing has a negligible effect on the pressure–area response of the vessel, as each device exerts approximately the same radial force, the slope of which is negligible compared to the LCR slope of the native artery. We show that 10% oversizing based on the observed diastolic diameter in the mid descending thoracic aorta results in a complete loss of contact between the device and the wall during systole, which could lead to an endoleak and stent migration. 20% oversizing reaches the Dacron enforced area limit (DEAL) during the pulse pressure and results in an effective zero-compliance in the later portion of systole.

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