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91.
92.
Integrative taxonomy of Parasabella and Sabellomma (Sabellidae: Annelida) from Australia: description of new species,indication of cryptic diversity,and translocation of some species out of their natural distribution range 下载免费PDF全文
Most nominal fan worm species belonging to the genus Parasabella Bush, 1905, and Sabellomma Nogueira, Fitzhugh & Silva‐Rossi, 2010 (Sabellidae, Annelida) lack unique morphological diagnostic features. Species diagnoses rely on a combination of attributes, often making reference to characters that are qualitatively or quantitatively continuous. This, together with a lack of knowledge about phenotypic intraspecific variation in most species, suggests that the sole use of morphological features is insufficient to identify and characterize some of these species. Examination of collections revealed that Parasabella is a common and diverse group of sabellids along the Australian coastline, although it had only been recorded here twice. The genus Sabellomma is here reported in Australia for the first time. Comparison of morphological data and nuclear (internal transcribed spacer) and mitochondrial (cytochrome oxidase I) DNA sequence data of 30 terminals in a range of analyses allowed us to assess the monophyly of Parasabella and its sister‐group relationship with Sabellomma and to examine some of the species boundaries and genetic diversity within lineages. The combined sequence data results indicate the presence of seven distinct genetic Parasabella lineages in Australia, four of which are assigned to previously described species (three are new records for Australia), and two are considered as a complex of species sharing a unique combination of characters, one of which is described as new. Another Parasabella species with distinct atypical radiolar eyes and a species of Sabellomma are also described as new. © 2015 The Linnean Society of London 相似文献
93.
Sinupret(?), a herbal medicinal product made from Gentian root, Primula flower, Elder flower, Sorrel herb, and Verbena herb is frequently used in the treatment of acute and chronic rhinosinusitis and respiratory viral infections such as common cold. To date little is known about its potential antiviral activity. Therefore experiments have been performed to measure the antiviral activity of Sinupret(?) oral drops (hereinafter referred to as "oral drops") and Sinupret(?) dry extract (hereinafter referred to as "dry extract"), in vitro against a broad panel of both enveloped and non-enveloped human pathogenic RNA and DNA viruses known to cause infections of the upper respiratory tract: influenza A, Chile 1/83 (H1N1) virus (FluA), Porcine Influenza A/California/07/2009 (H1N1) virus (pFluA), parainfluenza type 3 virus (Para 3), respiratory syncytial virus, strain Long (RSV), human rhinovirus B subtype 14 (HRV 14), coxsackievirus subtype A9 (CA9), and adenovirus C subtype 5 (Adeno 5). Concentration-dependent antiviral activity (EC(50) between 13.8 and 124.8 μg/ml) of Sinupret(?) was observed against RNA as well as DNA viruses independent of a viral envelope. Remarkable antiviral activity was shown against Adeno 5, HRV 14 and RSV in which dry extract was significantly superior to oral drops. This could be ascertained with different assays as plaque-reduction assays in plaque forming units (PFU), the analyses of a cytopathogenic effect (CPE) and with enzyme immunoassays (ELISA) to determine the amount of newly synthesised virus. Our results demonstrate that Sinupret(?) shows a broad spectrum of antiviral activity in vitro against viruses commonly known to cause respiratory infections. 相似文献
94.
Burr DC Morrone MC 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1564):504-515
How our perceptual experience of the world remains stable and continuous in the face of continuous rapid eye movements still remains a mystery. This review discusses some recent progress towards understanding the neural and psychophysical processes that accompany these eye movements. We firstly report recent evidence from imaging studies in humans showing that many brain regions are tuned in spatiotopic coordinates, but only for items that are actively attended. We then describe a series of experiments measuring the spatial and temporal phenomena that occur around the time of saccades, and discuss how these could be related to visual stability. Finally, we introduce the concept of the spatio-temporal receptive field to describe the local spatiotopicity exhibited by many neurons when the eyes move. 相似文献
95.
Dahm R van Marle J Quinlan RA Prescott AR Vrensen GF 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1568):1265-1277
The eye lens is avascular, deriving nutrients from the aqueous and vitreous humours. It is, however, unclear which mechanisms mediate the transfer of solutes between these humours and the lens' fibre cells (FCs). In this review, we integrate the published data with the previously unpublished ultrastructural, dye loading and magnetic resonance imaging results. The picture emerging is that solute transfer between the humours and the fibre mass is determined by four processes: (i) paracellular transport of ions, water and small molecules along the intercellular spaces between epithelial and FCs, driven by Na(+)-leak conductance; (ii) membrane transport of such solutes from the intercellular spaces into the fibre cytoplasm by specific carriers and transporters; (iii) gap-junctional coupling mediating solute flux between superficial and deeper fibres, Na(+)/K(+)-ATPase-driven efflux of waste products in the equator, and electrical coupling of fibres; and (iv) transcellular transfer via caveoli and coated vesicles for the uptake of macromolecules and cholesterol. There is evidence that the Na(+)-driven influx of solutes occurs via paracellular and membrane transport and the Na(+)/K(+)-ATPase-driven efflux of waste products via gap junctions. This micro-circulation is likely restricted to the superficial cortex and nearly absent beyond the zone of organelle loss, forming a solute exchange barrier in the lens. 相似文献
96.
Kinoshita M Yamazato K Arikawa K 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1565):688-696
The human eye is insensitive to the angular direction of the light e-vector, but several animal species have the ability to discriminate differently polarized lights. How the polarization is detected is often unclear, however. Egg-laying Papilio butterflies have been shown to see false colours when presented with differently polarized lights. Here we asked whether this also holds in foraging butterflies. After training individuals to feed on nectar in front of an unpolarized spectral light, we carried out three dual-choice tests, where the discrimination of (i) the spectral content, (ii) the light intensity, and (iii) the e-vector orientation were investigated. In the first test, the butterflies selected the trained spectrum irrespective of its intensity, and in the second test they chose the light with the higher intensity. The result of the e-vector discrimination test was very similar to that of the second test, suggesting that foraging butterflies discriminate differently polarized lights as differing in brightness rather than as differing in colour. Papilio butterflies are clearly able to use at least two modes of polarization vision depending on the behavioural context. 相似文献
97.
目的比较鸡胚尿囊膜试验(HET-CAM)作为一种眼刺激替代方法对产品或原料的评价。方法采用HET-CAM和兔眼Draize试验方法,对19种原料和23种化妆品及家用洗涤产品眼刺激性进行检测,对体内体外试验的结果进行统计比较。结果比较体内体外试验,原料和产品的kappa系数分别为0.826,0.531;灵敏度分别为100%,81.8%;特异度分别为85.7%,77.8%。结论 HET-CAM可作为Draize试验的替代试验,HET-CAM系统更适合对单纯化学品原料进行眼刺激试验。 相似文献
98.
目的研究不同浓度消旋山莨菪碱液对雏鸡形觉剥夺近视眼轴的影响。方法 3日龄雏鸡60只右眼遮盖半透明塑料膜,随机分为6组:给药组4组,不同浓度消旋山莨菪碱液(0.05%组,0.1%组,1%组,2.5%组),隔天行右眼球结膜下注射,每次给药50μL,共4次;对照组为生理盐水组,注射方法同给药组;单纯形觉剥夺组,不做干预。8 d后观察药物对眼轴的影响。结果 2.5%浓度组右眼与左眼眼轴差异显著小于低浓度组及对照组(P<0.05),给药组未发现组织病理毒性。结论消旋山莨菪碱对雏鸡近视眼轴增长有一定抑制作用,无毒副作用,有一定浓度依赖性。 相似文献
99.
Günter Purschke 《Invertebrate Biology》2011,130(2):115-128
Abstract. A retractable head region somewhat resembling the introvert of sipunculans is a characteristic feature of members of the annelid taxon Fauveliopsidae. The morphology of fauvelopsids is not well known, and additional data might help to resolve their relationships with other annelids and sipunculans. Ultrastructural investigations of the anterior end of adults of Fauveliopsis cf. adriatica revealed peculiar brain and sensory structures. From the neuropil of the brain, two pairs of lobes mainly composed of neuronal somata extend posteriorly into the peristomium and the following segment. The nuchal organs are embedded in the median pair of lobes, as are additional photoreceptor‐like sensory structures, the ocellar tubes, which are found at the bases of epidermal follicles that extend deeply into the brain. The retractor muscles of the prostomium are attached to the apices of these follicles, which are lined by tendon and supportive cells. The lumen of each follicle is completely filled with cuticular material that forms a rod. Monociliary sensory cells are present all along the length of each follicle; their cilia extend into the cuticle, and are oriented parallel to the longitudinal axis of the tube. Basally, each follicle forms an ovoid extension that is devoid of cuticular material and densely filled with numerous sensory processes—microvilli and cilia—of bipolar sensory cells. The terminal end of the 40‐μm‐deep follicle is formed by two conspicuous cells that contain numerous densely packed vesicles that resemble pigment granules. The ocellar tubes of fauveliopsids are strikingly similar to the ocular tubes of sipunculids. These similarities may reflect common ancestry or may represent convergent evolution; both alternatives are partially supported by previous morphological and molecular studies. 相似文献
100.
A scanning electron microscopic study of the skin and eye of UV‐B radiated ayu Plecoglossus altivelis (age 30 days, mean ± s . e . total length: 16·25 ± 0·11 mm) under laboratory condition showed marked changes when compared with the control fish without UV‐B radiation. The exposure of the fish to the radiation resulted in the destruction of microridges in the epidermis and exposed neuromast cells of the skin. Domed protrusions were also more common in the skin of UV‐B radiated fish than in the control fish. The appearance of mucus in both groups was different. In the control skin the mucus was spread over a wide area whereas in the treated fish the mucus was concentrated in a small area. The anastomozing structures of the microridges of the eyes were lost in UV‐B radiated fish and the microridges themselves were fewer in number, fragmented, and aggregated. Mucus cells, prominently visible in the control fish, were distorted in the treated fish. Cell contours were irregular in UV‐B radiated fish and cell to cell contacts had been lost in this group. 相似文献