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1.
Agapophytinae subf.n. is a highly diverse lineage of Australasian Therevidae, comprising eight described and two new genera: Agapophytus Guérin‐Méneville, Acupalpa Kröber, Acraspisa Kröber, Belonalys Kröber, Bonjeania Irwin & Lyneborg, Parapsilocephala Kröber, Acatopygia Kröber, Laxotela Winterton & Irwin, Pipinnipons gen.n. and Patanothrix gen.n. A genus‐level cladistic analysis of the subfamily was undertaken using sixty‐eight adult morphological characters and c. 1000 base pairs of the elongation factor‐1α (EF‐1α) protein coding gene. The morphological data partition produced three most parsimonious cladograms, whereas the molecular data partition gave a single most parsimonious cladogram, which did not match any of the cladograms found in the morphological analysis. The level of congruence between the data partitions was determined using the partition homogeneity test (HTF) and Wilcoxon signed ranks test. Despite being significantly incongruent in at least one of the incongruence tests, the partitions were combined in a simultaneous analysis. The combined data yielded a single cladogram that was better supported than that of the individual partitions analysed separately. The relative contributions of the data partitions to support for individual nodes on the combined cladogram were investigated using Partitioned Bremer Support. The level of support for many nodes on the combined cladogram was non‐additive and often greater than the sum of support for the respective nodes on individual partitions. This synergistic interaction between incongruent data partitions indicates a common phylogenetic signal in both partitions. It also suggests that criteria for partition combination based solely on incongruence may be misleading. The phylogenetic relationships of the genera are discussed using the combined data. A key to genera of Agapophytinae is presented, with genera diagnosed and figured. Two new genera are described: Patanothrix with a new species (Pat. skevingtoni) and Pat. wilsoni (Mann) transferred from Parapsilocephala, and Pipinnipons with a new species (Pip. kroeberi). Pipinnipons fascipennis (Kröber) is transferred from Squamopygia Kröber and Pip. imitans (Mann) is transferred from Agapophytus. Agapophytus bicolor (Kröber) is transferred from Parapsilocephala. Agapophytus varipennis Mann is synonymised with Aga. queenslandi Kröber and Aga. flavicornis Mann is synonymised with Aga. pallidicornis (Kröber).  相似文献   
2.
beta 2-Adrenergic bronchodilator and muscarinic cholinergic bronchoconstrictor agonists both stimulate ciliary activity in vitro. To test the hypothesis that increases in autonomic activity would result in increases in ciliary beat frequency (CBF) in vivo, a correlation analysis heterodyne laser light-scattering system was developed and validated to measure the stimulating effects of sympathomimetic and parasympathomimetic agonists on tracheal CBF in intact, anesthetized beagles. The mean baseline CBF from 42 studies of 274 measurements in 9 (5 male and 4 female) adult beagles was 6.6 +/- 1.1 Hz. The stimulating effects of a beta 2-adrenergic agonist, fenoterol, and a muscarinic cholinergic agonist, methacholine, on CBF were studied on four and eight beagles, respectively. The studies were randomized and blinded. Aerosolized 10(-5) M fenoterol stimulated the CBF from the base line of 6.8 +/- 2.5 to 32.0 +/- 17.9 Hz in four dogs. Aerosolized methacholine stimulated the CBF from the base line of 5.8 +/- 0.7 to 9.4 +/- 3.0 Hz for 10(-8) M, and to 12.6 +/- 3.1 Hz for 10(-6) M in eight dogs. These are the first data obtained in intact animals that demonstrate CBF in the lower respiratory tract is regulated by autonomic agonists.  相似文献   
3.
The crystal structure of V510, a chimeric type 2/type 1 poliovirus, has been determined at 2.6 A resolution. Unlike the parental Mahoney strain of type 1 poliovirus, V510 is able to replicate in the mouse central nervous system, due entirely to the replacement of six amino acids in the exposed BC loop of capsid protein VP1. Significant structural differences between the two strains cluster in a major antigenic site of the virus, located at the apex of the radial projection which surrounds the viral five-fold axis. Residues implicated in the mouse-virulence of poliovirus by genetic studies are located in this area, and include the residues which are responsible for stabilizing the conformation of the BC loop in V510. Despite evidence that this area is not involved in receptor binding in cultured primate cells, the genetic and structural observations suggest that this area plays a critical role in receptor interactions in the mouse central nervous system. These results provide a structural framework for further investigation of the molecular determinants of host and tissue tropism in viruses.  相似文献   
4.
To conduct laboratory studies in unsedated animals that were similar anatomically and physiologically to man, five full term baboons (four Papio cynocephalus anubis, one Papio cynocephalus cynocephalus) were hand-reared. These infants were used as unsedated animal models in short-term lung clearance studies conducted from birth to 2 years of age. The hand-rearing techniques described here encouraged the formation of an infant-human rearer bond that permitted us to control the level of expressed aggressive behavior as the infant matured. These techniques resulted in baboons which displayed subordinate behavior, showed positive reception to human contact (without evidence of negative stereotypic behavioral anomalies) and remained cooperative subjects for our investigations of short-term pulmonary clearance. The baboons generally were above average in weight in comparison to conspecifically-reared baboons of similar age, sex and species. Representative lung retention curves presented on one baboon demonstrate the feasibility of lung clearance studies in these hand-reared animals. Due to its suitability for unsedated studies, this baboon model may be considered for other types of laboratory investigations.  相似文献   
5.
Nature of the mammalian ciliary metachronal wave   总被引:1,自引:0,他引:1  
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6.
There has been a growing recent interest in how foliar herbivory may indirectly affect the belowground sub-system, but little is known about the belowground consequences of the identity, species composition or diversity of foliar herbivores. We performed an experiment, utilising model grassland communities containing three plant species, in which treatments consisted of addition of each of eight aphid species in single and in two- four- and eight-species combinations, as well as an aphid-free treatment. While aphid species treatments did not affect total plant biomass or productivity, aphid species identity had important effects on the relative abundance of the three plant species. This in turn affected the abundances of each of three groups of secondary consumers in the soil food web (bacterial- and fungal-feeding nematodes, and enchytraeids) but not primary consumers (microbes, herbivorous nematodes) or tertiary consumers (predatory nematodes). The fact that some trophic levels responded to treatments while others did not is consistent with trophic dynamic theory. Aphid species treatments also affected the community composition within each of the herbivorous, microbe-feeding and top predatory nematode groups, as well as diversity within the first two of these groups. However, aphid species diversity per se had few effects. There were specific instances in which specific aboveground and belowground response variables in two aphid species combinations differed significantly from those in both of the corresponding single aphid species treatments (apparently as a consequence of resource use complementarity between coexisting aphid species), but no instance in which increasing aphid diversity beyond two species had any effect. Our results provide evidence that the identity of aboveground consumers can have effects that propagate through multiple trophic levels in soil food webs in terms of consumer abundance, and composition and diversity within trophic levels.  相似文献   
7.
The effect of inhibitors was studied on the proteolytic activity of crude extracts of the mosquito Aedes aegypti (L.), prepared 25 h after blood intake. This activity is only partially inhibited by the lima bean trypsin inhibitor (LBTI) or by EDTA. Experiments with mixed inhibitors are used to indicate that, apart from the well characterized trypsin-like enzymes, at least three other proteinases are present. These are an LBTI-resistant serine proteinase, a metal chelator-sensitive proteinase, and a proteinase which can only be inhibited by the ovomucoid inhibitor. These newly described proteinases are inactive against several model substrates developed for mammalian enzymes. They are partially separable by ion-exchange chromatography.  相似文献   
8.
The incidence of pelvic inflammatory disease was investigated among parous women taking part in the Oxford-Family Planning Association contraceptive study. Hospital admission rates for "acute definite" disease were 1.51 per 1000 woman-years among those currently using an intrauterine device (IUD) and 0.14 per 1000 woman-years among those using other methods of birth control (age-standardised relative risk 10.5 to 1 with 95% confidence limits of 5.4 to 1 and 32 to 1). There was little evidence of an increased risk of such disease in ex-users of an IUD. Hospital admission for "chronic definite" disease, on the other hand, was commoner in ex-users of an IUD than in current users. Acute definite disease occurred somewhat more frequently during the early months of use of an IUD than during the later months. While the rate of such disease was increased in users of each type of device, the highest rate (8.1 per 1000 woman-years) was observed in users of the Dalkon shield. This rate, however, was based on only three affected women.  相似文献   
9.
10.
A new method for measuring mucociliary tracheal transport rates (MTTR's) is described. An aqueous aerosol containing albumin microspheres labeled with 99mTc was inhaled in such a manner that it was deposited in local concentrations in the large airways. These boli of microspheres were transported up the trachea and their MTTR's measured using a gamma camera. MTTR's were measured in 42 healthy nonsmoking adults (32 men and 10 women, mean age 28 yr). The mean MTTR's appeared to be log normally distributed with a geometric mean of 3.6 mm/min and a coefficient of variation of 75%. The MTTR's of men and women were similar. Each individual's short-term coefficient of variation was 25%. Twenty-two repeat studies 1 wk to 15 mo apart showed the variation within individuals was less than between individuals. The parasympatholytic drug, atropine (0.6 mg iv) decreased MTTR's for at least 3 h. Inhalation of the sympathomimetic drug, Th1165a increased MTTR's. Chronic and acute smoking did not appreciably change the MTTR'S.  相似文献   
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