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991.
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994.
H. Bannwarth N. Ikehara H. -G. Schweiger Agata Bartkiewicz T. Wilczok S. Berger F. Bodard G. Nuyts S. Bonotto G. Carraro A. Lüttke A. Bossus R. Kirchmann Sibylla Bratz G. Richter H. Broda A. C. Dazy S. Puiseux-Dao M. Durand A. Santa-Maria E. de Groot Thérèse Vanden Driessche J. -L. Guisset L. G. Harrison Janet Snell R. Verdi G. D. Zeiss Beverly R. Green Th. C. Lacalli D. Hoursiangou-Neubrun J. Hrib E. M. Kof V. I. Kefeli M. Lenski G. Werz Angela Lüttke H. Mundt Petra Christiansen M. Paques M. Brouers H. H. Paradies H. Borghi C. Brun J. M. Provost M. Durrand T. Moini-Zanjani R. Schmid H. -U. Koop D. Wolff Ikuko Shihira-Ishikawa Dirce Mithico Yamaoka Yano R. Shoeman L. Wasilewska M. Viro K. Kloppstech K. Apel B. Zimmer K. Zetsche 《Protoplasma》1981,105(3-4):347-368
995.
Body temperatures during rest and exercise in residents and sojourners in hot climate 总被引:1,自引:0,他引:1
J. Raynaud J. P. Martineaud O. P. Bhatnagar H. Vieillefond J. Durand 《International journal of biometeorology》1976,20(4):309-317
Rectal (Tre), mean skin temperature (
sk) and sweating rate (
) were measured in 4 residents of temperate climate under acute moderate heat exposure (designated EE in such an experimental situation), after 3 weeks in India (designated as EI) and in 8 Indian residents (designated as II) both at rest and during submaximal exercises at 2 different intensities. At rest, Tre is higher in EI (37.6°C) than in EE (36.8°C, P<0.01) and reaches 37.8°C in II. At the end of exercise, the increment in Tre seems to depend on work load only and to be independent of thermal environment; S follows a similar pattern in the 3 groups of subjects:
sk is altered neither by exercise nor acclimatization. Under chronic heat exposure compared to acute conditions: (1) identical
is achieved with higher Tre and similar
sk so that the linear relationships
vs Tre is shifted to the right. (2) the Tre —
sk difference is greater at rest and during exercise: hence, skin blood flow, calculated from heat balance equation diminishes. In hot climate, a rise in Tre seems to be an adaptive response which allows the body to reduce skin blood flow. 相似文献
996.
The influence of dietary polyunsaturated fatty acids on fatty acid composition, cholesterol and phospholipid content as well as 'fluidity' (assessed by fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) probes) of brain synaptic plasma membranes (SPM) and their interactions with chronic ethanol effects were studied in rats fed for two generations with diets either devoid of (n-3) fatty acids (sunflower oil diet), rich in alpha-linolenic acid (soya oil diet) or in long chain (n-3) fatty acids (sunflower + cod liver oil diet). Results were compared with rats fed standard lab chow. Sunflower oil led to an increase in the (n-6)/(n-3) ratio in the membranes with an increase of the 'fluidity' at membrane apolar level; sunflower + cod liver oil decreased the (n-6)/(n-3) ratio without affecting membrane 'fluidity' while no difference was seen between the SPM of rats fed soya oil and standard diet. After 3 weeks alcohol intoxication in rat fed the standard diet: oleic alpha-linoleic acids and cholesterol levels were increased, arachidonic acid and the double bond index/saturated fatty acids were decreased and there was a decrease of 'fluidity' in the lipid core of the SPM. Soya oil almost totally abolished these usually observed changes in the SPM fatty acids composition but increased oleic acid and cholesterol without any change in fluidity. Sunflower oil led to the same general alterations of fatty acid as seen with standard diet but to a greater extent, with decrease of the 'fluidity" at the apolar level and in the region probed by TMA-DPH. When sunflower oil was supplemented with cod liver oil, oleic and alpha-linoleic acids were increased while the 'fluidity' of the apolar core of SPM was decreased. So, the small changes in fatty acid pattern seem able to modulate neural properties i.e. the responses to a neurotoxic like ethanol. A structurally specific role of PUFA is demonstrated by the pernicious effects of the alpha-linolenic acid deficient diet which are not totally prevented by the supply of long chain (n-3) PUFA. 相似文献
997.
C. A. Kubanek J. H. Hill R. A. Van Deusen D. P. Durand 《Journal of Phytopathology》1991,133(2):99-104
Three populations of Arabidopsis thaliana (L.) Heynh. were inoculated with three isolates of Plasmodiophora brassicae Woron. Inoculation of young Arabidopsis plants caused clubbing of roots and, in the late flowering population CrGC 9–4, infection of shoots. In this population, the number of inoculated plants reaching the flowering stage was reduced, and the majority of plants died prematurely. Symptoms of shoot infections were compressed rosettes with thickened and stunted leaves containing resting spores of P. brassicae. The results showed clearly that A. thaliana is susceptible to P. brassicae. 相似文献
998.
O Bailliart H Marotte H Normand J P Martineaud J Durand 《Archives internationales de physiologie et de biochimie》1990,98(4):179-192
We measured common carotid blood flow using a range gated Doppler velocimeter, and internal and external blood velocities using a continuous Doppler in 20 lowlanders at sea level, under normal barometric pressure, in 10 subjects in an altitude chamber under a barometric pressure of 462 Torr (61.6 KPa) and then in 5 of them over a 3-weeks period at 3850 m of elevation (475 Torr = 63.3 KPa). The same measurements were also performed in 20 permanent residents at 3850 m. Common carotid blood flow was 15% higher in all subjects exposed to high altitude, due to a lowering in downstream resistances since systemic blood pressure did not change at high altitude. The increase in common carotid blood flow was the result of an immediate increase in internal carotid blood velocities observed in the altitude chamber as well as after the arrival at high altitude, but a few days later those velocities in the internal carotid artery declined to values similar to those observed at sea level. In the same time velocities in external carotid artery rose at high altitude, remained steadily elevated and the result is a permanent increase in common carotid blood flow at altitude. In all subjects we performed the same measurements, during an acute inhalation of gas mixtures to try to quantify the mechanisms controlling the changes in common carotid blood flow while changing gas inhalation. In the limits of the variations in PO2 (60 to 400 Torr) and in PCO2 (30 to 50 Torr) the stimulation by CO2 is twice more efficient than the O2 stimulation on vasomotion. 相似文献
999.
Interleukin-4 receptors on human blood mononuclear cells 总被引:2,自引:0,他引:2
We have studied regulation of the expression of the interleukin-4 receptor (IL-4R) on human blood mononuclear cells (PBMC) using both 125I-IL-4 binding assay and flow cytometric analysis of biotinylated IL-4 (B-IL-4) binding. PBMC express approximately 300 high-affinity IL-4R per cell (Kd = 25-100 pM). Activation of PBMC for 60-80 hr by phytohemagglutinin (PHA) or concanavalin A (Con A) results in a 2- to 4.5-fold increase of IL-4R number without alteration of IL-4R affinity for IL-4. Binding of B-IL-4 showed that IL-4R expression is upregulated on virtually all PHA-stimulated PBMC, whereas it mostly concerns larger cells among Con A-activated PBMC. Reculture of PHA-blasts with 1 nM IL-4 further upregulates IL-4R expression to a level approximately 10-fold higher than observed on freshly isolated PBMC. Interestingly, IL-4 is able to reinduce high IL-4R levels on cells that have been deprived of IL-4 for 20 hr and IL-2 is almost as efficient. Finally, SDS-PAGE analysis of IL-4-binding molecules on unstimulated, PHA- and PHA/IL-4-activated PBMC revealed the same three peptides of MW 140-130, 80-75, and 70-65 kDa, as shown on human cell lines. 相似文献
1000.
Louis M. Mansky Robert E. Andrews Donald P. Durand John H. Hill 《Plant Molecular Biology Reporter》1990,8(1):13-17
A method, termed press blotting, is described which allows localization of plant virus in infected leaf tissue. Press blotting
should have broad applicability to identifiying the distribution and location of proteins expressed in plants. 相似文献