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1.
Booknotes     
MR 《Biology & philosophy》1987,2(1):117-122
  相似文献   
2.
This paper describes the morphology and response characteristics of two types of paired descending neurons (DNs) (classified as DNVII1 and DNIV1) and two lobula neurons (HR1 and HP1) in the honeybee, Apis mellifera.
1.  The terminal arborizations of the lobula neurons are in juxtaposition with the dendritic branches of the DNs (Figs. 2, 3b, 5). Both of the DNs descend into the ipsilateral side of the thoracic ganglia via the dorsal intermediate tract (Fig. 6) and send out many blebbed terminal branches into the surrounding motor neuropil (Figs. 3c, 7).
2.  Both the lobula and descending neurons respond in a directionally selective manner to the motion of widefield, periodic square-wave gratings.
3.  The neurons have broad directional tuning curves (Figs. 10, 11). HR1 is maximally sensitive to regressive (back-to-front) motion and HP1 is maximally sensitive to progressive (front-to-back) motion over the ipsilateral eye (Fig. 11). DNVII1 is maximally sensitive when there is simultaneous regressive motion over the ipsilateral eye and progressive motion over the contralateral eye (Fig. 12a). Conversely, DNIV1 is optimally stimulated when there is simultaneous progressive motion over the ipsilateral eye and regressive motion over the contralateral eye (Fig. 12b).
4.  The response of DNIV1 is shown to depend on the contrast frequency (CF) rather than the angular velocity of the periodic gratings used as stimuli. The peak responses of both regressive and progressive sensitive DNs are shown to occur at CFs of 8–10 Hz (Figs. 13, 14).
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5.
Pinocytic activity was quantified for rat yolk sacs incubated in a medium that was either serum-free or contained 10% (v/v) of calf serum. Absence of serum from the medium caused a small increase in the rate of pinosome formation, as determined by the rates of capture of both 125I-labelled poly(vinylpyrrolidone) and [14C]sucrose. In contrast, the rates of uptake of substrates ingested by adsorptive pinocytosis were greatly enhanced when serum proteins, which compete for the same binding sites on the plasma membrane as used by adsorbing substrates, were absent. Elimination of such competition greatly simplifies the quantitative analysis of the binding process, and permitted a detailed study of the binding to the plasma membrane of formaldehyde-denatured bovine serum albumin, a protein that is rapidly digested within the lysosomal system after its pinocytic capture. Binding obeyed Michaelis-Menten kinetics and showed a dissociation constant of approx. 1 micron, indicating the high affinity of this protein for binding sites on the surface of actively pinocytosing yolk-sac cells.  相似文献   
6.

Introduction

Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.

Methods

Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).

Results

The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.

Conclusion

A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.

Trial registration

NCT01515163.  相似文献   
7.

Background and Purpose

In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements.

Materials and Method

In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described using medians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between the median of entire thrombus measurements and commonly applied manual measurements using 3 regions of interest were determined using linear regression.

Results

Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density.

Conclusions

Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, discrimination of low and high density thrombi is improved with the automated method.  相似文献   
8.
The current status of kinetoplastids phylogeny and evolution is discussed in view of the recent progresses on genomics. Some ideas on a potential framework for the evolutionary genomics of kinetoplastids are presented.  相似文献   
9.
Intracoronary brachytherapy has recently emerged as a new therapy to prevent restenosis. Initial experimental work was achieved in animal models and the results were assessed by histomorphometry. Initial clinical trials used angiography to guide dosimetry and to assess efficacy. Intravascular ultrasound (IVUS) permits tomographic examination of the vessel wall, elucidating the true morphology of the lumen and transmural components, which cannot be investigated on the lumenogram obtained by angiography. This paper reviews the use of IVUS in the clinical studies of brachytherapy conducted to date. IVUS allows clinicians to make a thorough assessment of the remodeling of the vessel and appears to have a major role to play in facilitating understanding of the underlying mechanisms of action in this emerging field. The authors propose that state-of-the-art IVUS techniques should be employed to further knowledge of the mechanisms of action of brachytherapy in atherosclerotic human coronary arteries.  相似文献   
10.
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