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71.
 The present study was conducted to investigate the distribution and immunohistochemical characteristics of ascending and descending projection neurons of the rat superior olivary complex (SOC), a group of interrelated brainstem nuclei. Ascending neurons were identified by injection of cholera toxin B subunit (CTB) into the central nucleus of the inferior colliculus (IC), descending neurons were labeled by application of Fluoro-Gold (FG) into the scala tympani of the cochlea, ipsilaterally to the IC injection. In accordance with the literature, we observed neurons innervating the IC located in the lateral superior olivary nucleus (LSO) and dorsal periolivary groups (DPO) on both sides, in the superior paraolivary nucleus (SPO) predominantly ipsilateral, as well as in the ipsilateral medial superior olivary nucleus (MSO) and the medial nucleus of the trapezoid body (MNTB). Cochlear projection neurons were found predominantly in the ipsilateral LSO as well as in the bilateral SPO, DPO, MSO and MNTB. In addition, a considerable population of neurons in the ipsilateral LSO and SPO were identified as being both ascending and descending. To further characterize these double-projecting neurons, brainstem sections were incubated in antisera directed against different neuroactive substances. The majority of ascending/descending cells in the LSO contained calcitonin gene-related peptide, but not substance P (SP), met-enkephalin (ENK) or tyrosine hydroxylase (TH). Some of these neurons apparently were contacted by ENK- or SP-immunoreactive fibers and terminals. In addition, we found TH-immunoreactive neurons in the lateral MNTB region. These neurons, which were labeled upon tracer injection into the cochlea (but not upon IC injection), probably belong to the C1 catecholaminergic cell group and may represent a division of the uncrossed olivocochlear bundle. The present results reveal the existence of a previously unknown subpopulation of SOC neurons that project to both the cochlea and the inferior colliculus. Their CGRP immunoreactivity and their uncrossed projection pattern provide evidence that they may belong to the cholinergic, putatively excitatory cell group. Received: 4 January 1999 / Accepted: 17 February 1999  相似文献   
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IntroductionUnderestimation of zoonoses is exacerbated in low and middle-income countries due mainly to inequalities with serious consequences in healthcare. This is difficult to gauge and reduce the impact of those diseases. Our study focuses on Paraguay, where the livestock industry is one of the major components of the country’s economy. Therefore, the rationale of this study was to develop a case study in Paraguay to estimate the dual impact of zoonotic diseases on both the human health and animal health sector and thus determine the societal burden of such diseases.Methodology/Principal findingsWe conducted a systemic review (including a meta-analysis) to assess the burden of zoonoses in Paraguay, including official reports and grey literature of disease incidence and prevalence. We estimated the Disability Adjusted Life Years (DALYs) and Zoonosis Disability Adjusted Life Years (zDALYs) to measure the difference between the current health status and the desired health situation of animals and the Paraguayan population based on 50 zoonotic diseases suggested by the WHO (World Health Organization), OIE (World Organization for Animal Health) and the National Health in Paraguay. The total DALYs represent 19,384 (95% CI: from 15,805 to 29,733), and zDALYs, 62,178 (95% CI: from 48,696 to 77,188). According to the results, the priority pathogens for DALYs are E. coli, Trypanosoma cruzi, Leishmania spp, and Toxoplasma gondii. When we include the additional animal health burden, the most important pathogens are Brucella spp, E. coli, Trypanosoma cruzi, and Fasciola hepatica for zDALYs.Conclusion/SignificanceThis is the first study to integrate DALYs and zDALYs with important clues related to the health status of Paraguay. Through DALYs and zDALYs, our perspective becomes more complete because we consider not only human health but also animal health. This is important for setting priorities in disease control, especially in a society where livestock contribute significantly to the economy and to human well-being.  相似文献   
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Samples of Dreissena polymorpha were collected at several sites along the River Shannon navigation in Ireland, to determine the occurrence and distribution of their obligate host-specific commensalistic ciliate, Conchophthirus acuminatus, in this newly invaded region. Mussels collected by various methods were fixed immediately in 75% ethanol, in which they were later dissected under a stereoscopic microscope, beginning with thorough flushing of the mantle cavity and removal of the gills. One ml of sediment flushed from the mantle cavity and dissection residue of each mussel was examined under a compound light microscope using brightfield, phase-contrast, and differential-interference-contrast optics. Of 180 mussels examined, 125 (69.44%) harbored C. acuminatus. The ciliates were invariably well fixed and easily identifiable in all preparations. Mean sampling intensity for infected mussels was 8.47 ciliates per ml of sediment. Both prevalence and sampling intensity varied between sites, but no pattern was discernible. The present results are consistent with other reports of C. acuminatus being the most widespread and abundant symbiont of D. polymorpha throughout Europe, often occurring where no other symbionts occur. Its occurrence in Ireland indicates introduction of the mussels as adults, since planktonic veliger larvae are not known to harbor ciliates. Following similar reasoning, it is possible that the earlier North American invasion by D. polymorpha included only veligers, since C. acuminatus has not been found on that continent. Using these simple and quick methods, the ciliates could be easily identified and counted to give general comparative data among sites regarding intensity and prevalence. Thus, this method has promise for future efforts to obtain basic information rapidly in newly invaded systems.  相似文献   
75.
Lumbar spine accessory movements, used by therapists in the treatment of patients with low back pain, is thought to decrease paravertebral muscular activity; however there is little research to support this suggestion. This study investigated the effects of lumbar spine accessory movements on surface electromyography (sEMG) activity of erector spinae.A condition randomised, placebo controlled, repeated measures design was used. sEMG measurements were recorded from 36 asymptomatic subjects following a control, placebo and central posteroanterior (PA) mobilisation to L3 each for 2 min. The therapist stood on a force platform while applying the PA mobilisation to quantify the force used. The PA mobilisation applied to each subject had a mean maximum force of 103.3 N, mean amplitude of force oscillation of 41.1 N, and a frequency of 1.2 Hz. Surface electromyographic data were recorded from the musculature adjacent to L3, L5 and T10.There were statistically significant reductions of 15.5% (95% CI: 8.0–22.5%) and 17.8% (95% CI: 12.9–22.4%) in mean sEMG values following mobilisation compared with the control and placebo, respectively.This study demonstrates that a central PA mobilisation to L3 results in a statistically significant decrease in the sEMG activity of erector spinae of an asymptomatic population.  相似文献   
76.
Several methods for material characterization and surface analysis such as scanning electron microscopy (SEM), energy dispersion X-ray analysis (EDX), environmental scanning electron microscopy (ESEM), petrographic analyses, Mössbauer spectroscopy (MS), conventional X-ray diffraction (XRD), grazing incidence diffraction (GID), Raman spectroscopy (RS), other spectroscopic techniques like X-ray photoelectron spectroscopy (XPS), reflection electron energy-loss spectroscopy (REELS) and advanced combined applications of synchrotron based μ-X-ray diffraction/μ-X-ray fluorescence (SR-μXRD/μXRF) can be used for assessing weathering and biodeterioration effects on materials (such as stone buildings, metallic artefacts, pigments, mixtures, and processes) of cultural property. Molecular biology techniques to identify the microbial components of biofilms are also described. Different examples of the use of these methods in the field of cultural property preservation are presented.  相似文献   
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For the development of a scheme for quantitative experimental estimation of internal motion in the complex human milk hexasaccharide lacto‐N‐di‐fuco hexose I (LNDFH I), we measured a large number of experimental residual dipolar couplings in liquid crystal orienting media. We present a total of 40 13C? 1H and 1H? 1H dipolar coupling values, each representing distinct directions of internuclear vectors. The NMR data were interpreted with established methods for analysis of rigid subdomains of the oligosaccharide as well as a novel method in which dipolar couplings were calculated over an ensemble of conformers from a solvent Molecular Dynamics trajectory using multiple linear regression analysis. The Lewisb epitope region of LNDFH I assumed a single unique conformation with internal motion described by fluctuations of 5–10° in glycosidic dihedral angles consistent with previous studies. Greater flexibility was observed for the remaining GlcNAc1→3‐β‐D ‐Gal and β‐D ‐Gal1→4Glc linkages, with the former glycosidic linkage existing in a conformational exchange among three states. The results were also supported by similar results of calculations carried out with conformers obtained from a simple Monte Carlo simulation without explicit solvent. © 2010 Wiley Periodicals, Inc. Biopolymers 95: 39–50, 2011.  相似文献   
79.
The animal gut commonly contains a large reservoir of symbiotic microbes. Although these microbes have obvious functions in digestion and immune defence, gut microbes can also affect behaviour. Here, we explore whether gut microbiota has a role in kin recognition. We assessed whether relatedness, familiarity and food eaten during development altered copulation investment in three species of Drosophila with diverse ecologies. We found that a monandrous species exhibited true kin recognition, whereas familiarity determined kin recognition in a species living in dense aggregations. Finally, in a food generalist species, food eaten during development masked kin recognition. The effect of food type on copulation duration, in addition to the removal of this effect via antibiotic treatment, suggests the influence of bacteria associated with the gut. Our results provide the first evidence that varied ecologically determined mechanisms of kin recognition occur in Drosophila, and that gut bacteria are likely to have a key role in these mechanisms.  相似文献   
80.
This paper utilizes the framework of Karl Popper’s 3-world ontology to make the case that forensic science is a specialized coding system that establishes meaningful connections between the world of biology (world 1) and the world of human society (world 3). Forensic science is a cross-disciplinary endeavor that uses scientific methods to determine what transpired in a crime so the legal system can determine how to prosecute the offender(s). On a Popperian analysis of forensic science, world 1 consists of evidence gathered at the crime scene, which enables investigators to develop a detailed reconstruction of the incident for consideration under the legal and ethical codes of society, which are products of world 3. Understanding forensic science in this way serves two purposes: first, it extends Marcello Barbieri’s code biology into the realm of philosophical considerations in science, law and ethics; and second, it situates forensic science within the larger context of debates in contemporary philosophy of science.  相似文献   
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