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21.
The role of progesterone (P) as an androgen antagonist in Mongolian gerbil territorial marking was assessed in the present investigation. Twenty-seven mature males were observed for two consecutive weeks in a marking apparatus. On the basis of the average of the two sessions, subjects were matched and assigned to one of three groups. All animals were orchidectomized and tested three weeks after surgery. Three days after a single postoperative session a schedule of hormonal replacement was initiated. Group 1 was administered 640 μg testosterone propionate (TP). Group 2 received 640 μg TP followed immediately by 3 mg P. A third group received 640 μg TP followed by a 1 mg injection of P. Subjects were tested for marking 24 hr after the injection for a cumulative period of 6 wk.Results indicated that (a) castration drastically reduced marking; (b) TP alone and TP + 1 mg P restored the behavior; (c) TP + 3 mg P inhibited its restoration; and (d) a significant interaction was present between hormonal therapy and the 6-wk testing interval. However, all three hormonal treatments restored sebaceous gland dimensions. Results are discussed in terms of a model of hormone-gene action.  相似文献   
22.
The phospholipids of intact microsomal membranes were hydrolysed 50% by phospholipase C of Clostridium welchii, without loss of the secretory protein contents of the vesicle, which are therefore not permeable to the phospholipase. Phospholipids extracted from microsomes and dispersed by sonication were hydrolysed rapidly by phospholipase C-Cl. welchii with the exception of phosphatidylinositol. Assuming that only the phospholipids of the outside of the bilayer of the microsomal membrane are hydrolysed in intact vesicles, the composition of this leaflet was calculated as 84% phosphatidylcholine, 8% phosphatidylethanolamine, 9% sphingomyelin and 4% phosphatidylserine, and that of the inner leaflet 28% phosphatidylcholine, 37% phosphatidylethanolamine, 6% phosphatidylserine and 5% sphingomyelin. Microsomal vesicles were opened and their contents released in part by incubation with deoxycholate (0.098%) lysophosphatidylcholine (0.005%) or treatment with the French pressure cell. Under these conditions, hydrolysis of the phospholipids by phospholipase C-Cl. welchii was increased and this was mainly due to increased hydrolysis of those phospholipids assigned to the inner leaflet of the bilayer, phosphatidylethanolamine and phosphatidylserine. Phospholipase A2 of bee venom and phospholipase C of Bacillus cereus caused rapid loss of vesicle contents and complete hydrolysis of the membrane phospholipids, with the exception of sphingomyelin which is not hydrolysed by the former enzyme.  相似文献   
23.
The Migadopini are a small tribe of Carabidae with 47 species that occur in South America, Australia, and New Zealand, in the sub-Antarctic areas. In South America, most of the genera inhabit areas related to sub-Antartic Nothofagus forest except two monogeneric genera, the Ecuadorian genus Aquilex Moret and the Pampean genus Rhytidognathus Chaudoir. These two genera are geographically isolated from the remaining five South American genera. New material of Rhytidognathus from the northeast of Buenos Aires province and from Entre Ríos province permits establishing that the previous records of Rhytidognathus ovalis (Dejean) for Argentina were erroneous and that it belongs to a new species. Based on external morphological characters and from male and female genitalia we describe Rhytidognathus platensis as a new species. In this contribution we provide illustrations, keys, habitat characteristics and some biogeographic considerations on the distribution of Rhytidognathus.  相似文献   
24.
We review the New Caledonian representatives of the Australasian endemic hydroptiline genus Acritoptila, based on examination of a considerable collection of material in the Swedish Museum of Natural History and of types of previously established species. A key for identification of males is given and includes 3 species newly described here: A. parallela sp. n., A. forficata sp. n. and A. macrospina sp. n. For all New Caledonian species, male genitalia are illustrated, and for 5 associated females, distinctive features are illustrated and described.  相似文献   
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26.
Airborne pollen and spore levels were monitored at seven sites in New Zealand using the Intermittent Cycling Rotorod sampler during the summer of 1988/1989. Grasses formed the major component of atmospheric pollen levels during spring and summer at every locality. Peak levels of grass and total pollen occurred during December or late November, with a slight latitudinal lag apparent at the more southern sites. Highest levels were recorded at the smaller rural centres of Gore and Kaikohe and the lowest at the larger urban centres of Auckland, Christchurch and Wellington. We make a first approximation of the likely risk to hayfever and allergic asthma patients at each of the seven centres. For example, significantly higher grass pollen levels were experienced at Kaikohe on 44% and 65% of days during November and December, compared with just 15% and 8% at Auckland. By recording the flowering seasons of the principal allergenic grass species at each locality, we determined the potentially allergenic grasses contributing to peak pollen levels, the most ubiquitous being tall fescue (Festuca arundinacea Schreb.), ryegrass (Lolium perenne L.,L. multiflorum Lam.), cocksfoot (Dactylis glomerata L.), Yorkshire fog (Holcus lanatus L.) and sweet vernal (Anthoxanthum odoratum L.). Corresponding author. Deceased.  相似文献   
27.
Brachypalpus (Brachypalpus) longifacies sp. nov. is described and illustrated from Eastern Asia (Russian Far East and Japan). It differs from other species of the nominative subgenus by several unusual characters, i.e. face in profile weakly convex dorsally and concave ventrally, antennae very elongated, and abdomen with reddish transversal maculae on 2nd tergum (male) or 2nd and 3rd terga (female). A key is given for known species of the subgenus Brachypalpus.LSID: urn:lsid:zoobank.org:pub:634CB6E2-B2C1-40EC-8811-BF3DD4BDE69A  相似文献   
28.
The establishment, spread and subsequent degradation of existing environments by invasive species is a worldwide problem affecting native and agricultural ecosystems. The phenomenal cost to governments as a result of research and eradication or control drives the need to understand invasion characteristics. In this paper we develop a method for modelling the boundary of an invasion over time with model inputs being the initial distribution of the invasion and the speed at which the invasion front moves over time. This speed function can depend on the topography of the ground cover and we consider examples of homogeneous and inhomogeneous spread. The possibility of a long-distance dispersal event occurring is also considered. In particular, examples of the spread of emergent weeds and weeds which favour creeks and river beds in New Zealand are presented.  相似文献   
29.
Nektonic pueruli of the spiny lobster, Jasus edwardsii, were caught from two locations about 20 km apart across the continental shelf on the south east of the North Island, New Zealand. The pueruli were assayed for total protein, glucose, glycogen, and lipid content. Only the lipid content differed between pueruli caught onshore and offshore (mean difference=3.1 mg or 3.4% of dry mass). The average difference in lipid content measured over this distance was used to calculate the rate of energy consumption and timing for pueruli to actively swim from the continental shelf to shore. These results confirmed previous theoretical estimates and indirect measures. Furthermore, the rate of energy consumption would allow all of the pueruli caught offshore to swim to shore based on their total measured lipids. However, some individuals with low energy stores may be energetically compromised at arrival which may affect their subsequent moulting and survival. The results of this study indicate that lipid is the primary format for energy storage of the nektonic puerulus of the spiny lobster and that these lipid reserves have sufficient energetic capacity to allow the puerulus to actively swim the distance across the shelf to settle on the coast.  相似文献   
30.
Two new oleanane-type triterpene saponins, identified as 16α-hydroxy-22-O-angeloyl-23-formyl-28,31-dihydroxymethylene-olean-12-ene-3β-O-{β-d-galactopyranosyl-(1  2)[β-d-xylopyranosyl-(1  2)-α-l-arabinopyranosyl(1  3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B1, 1) and 22-O-hydrocinnamoyl-23-formyl-28-dihydroxymethylene-olean-12-ene-3β-O-{β-d-glucopyranosyl-(1  2)[β-d-xylopyranosyl-(1  2)-α-l-arabinopyranosyl(1  3)]-β-d-glucopyranosiduronic acid} (oleiferasaponin B2, 2), were isolated from the seed cake of Camellia oleifera Abel. Their structures were established by extensive 1D- and 2D-NMR experiments along with TOF-MS analysis and acid hydrolysis. The cytotoxicity of the isolated compounds was evaluated in four human carcinoma cell lines: A 549, SK-OV-3, SK-MEL-2 and HCT15. Both compounds 1 and 2 exhibited significantly cytotoxic activity with IC50 values of 18.5 μM (A549), 11.3 μM (SK-OV-3), 13.9 μM (SK-MEL-2) and 1.6 μM (HCT15) for 1 and IC50 values of 8.4 μM (A549), 6.3 μM (SK-OV-3), 9.2 μM (SK-MEL-2) and 0.8 μM (HCT15) for 2. In addition, compound 2 showed more effective cytotoxic activity than compound 1.  相似文献   
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