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21.
Summary 1. An immunohistochemical study has been made of the hypothalamo-neurohypophyseal system of the dog, 20h after crushing the pituitary stalk.2. By use of a cross-species-reactive neurophysin antiserum it was shown that neurophysin is a component of the axons which originate in the supraoptic and paraventricular nuclei and terminate around blood vessels in the posterior pituitary.3. Neurophysin specific fluorescence accumulated in axons proximal to the constriction but was absent from the axons immediately distal to the site of injury.4. In dogs left for six days it was shown by radioimmunoassay that the amount of neurophysin in the hypothalamus and stalk proximal to the constriction increased twofold while that remaining in the posterior pituitary and stalk distal to the constriction decreased five-fold over the same period.5. The results are interpreted as evidence for a rapid axonal transport of neurophysin from its site of synthesis in the cell bodies of the hypothalamus to the posterior pituitary. Acknowledgements: This work was supported by a research grant to D. B. Hope from the Medical Research Council. L. O. Uttenthal was supported by a Medical Research Training Award and B. G. Livett by a Nuffield Dominions Trust Demonstratorship (Australia). We thank Mrs. Marion Martin for radioimmunoassay of neurophysin, Miss Wendy Jones for technical assistance and the U.C.L.A. Brain Information Service for help with the bibliography.  相似文献   
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Abstract: The two odontocete taxa Squalodon grateloupii and Patriocetus ehrlichii, both the type species of their respective genera, have been at the centre of a great deal of taxonomic confusion. Originally regarded to be conspecific, these two taxa have been the subject of a bewildering taxonomic debate lasting for more than a century, which recently led to the suggestion to abandon these widely used names and replace S. grateloupii with the similar, yet independently and later proposed name S. gratelupi as the type species of Squalodon. Here, we attempt to summarise the events leading to the current confused situation in the hope of resolving this issue once and for all and argue that the name Squalodon grateloupii, as originally proposed, should be reinstated.  相似文献   
24.

Background

Frontotemporal lobar degeneration (FTLD) represents a clinically, pathologically and genetically heterogenous neurodegenerative disorder, often complicated by neurological signs such as motor neuron-related limb weakness, spasticity and paralysis, parkinsonism and gait disturbances. Linkage to chromosome 9p had been reported for pedigrees with the neurodegenerative disorder, frontotemporal lobar degeneration (FTLD) and motor neuron disease (MND). The objective in this study is to identify the genetic locus in a multi-generational Australian family with FTLD-MND.

Methods

Clinical review and standard neuropathological analysis of brain sections from affected pedigree members. Genome-wide scan using microsatellite markers and single nucleotide polymorphism fine mapping. Examination of candidate genes by direct DNA sequencing.

Results

Neuropathological examination revealed cytoplasmic deposition of the TDP-43 protein in three affected individuals. Moreover, we identify a family member with clinical Alzheimer's disease, and FTLD-Ubiquitin neuropathology. Genetic linkage and haplotype analyses, defined a critical region between markers D9S169 and D9S1845 on chromosome 9p21. Screening of all candidate genes within this region did not reveal any novel genetic alterations that co-segregate with disease haplotype, suggesting that one individual carrying a meiotic recombination may represent a phenocopy. Re-analysis of linkage data using the new affection status revealed a maximal two-point LOD score of 3.24 and a multipoint LOD score of 3.41 at marker D9S1817. This provides the highest reported LOD scores from a single FTLD-MND pedigree.

Conclusion

Our reported increase in the minimal disease region should inform other researchers that the chromosome 9 locus may be more telomeric than predicted by published recombination boundaries. Moreover, the existence of a family member with clinical Alzheimer's disease, and who shares the disease haplotype, highlights the possibility that late-onset AD patients in the other linked pedigrees may be mis-classified as sporadic dementia cases.  相似文献   
25.
Predictions on the consequences of the rapidly increasing atmospheric CO2 levels and associated climate warming for population dynamics, ecological community structure and ecosystem functioning depend on mechanistic energetic models of temperature effects on populations and their interactions. However, such mechanistic approaches combining warming effects on metabolic (energy loss of organisms) and feeding rates (energy gain by organisms) remain a key, yet elusive, goal. Aiming to fill this void, we studied the metabolic rates and functional responses of three differently sized, predatory ground beetles on one mobile and one more resident prey species across a temperature gradient (5, 10, 15, 20, 25 and 30 °C). Synthesizing metabolic and functional‐response theory, we develop novel mechanistic predictions how predator–prey interaction strengths (i.e., functional responses) should respond to warming. Corroborating prior theory, warming caused strong increases in metabolism and decreases in handling time. Consistent with our novel model, we found increases in predator attack rates on a mobile prey, whereas attack rates on a mostly resident prey remained constant across the temperature gradient. Together, these results provide critically important information that environmental warming generally increases the direct short‐term per capita interaction strengths between predators and their prey as described by functional‐response models. Nevertheless, the several fold stronger increase in metabolism with warming caused decreases in energetic efficiencies (ratio of per capita feeding rate to metabolic rate) for all predator–prey interactions. This implies that warming of natural ecosystems may dampen predator–prey oscillations thus stabilizing their dynamics. The severe long‐term implications; however, include predator starvation due to energetic inefficiency despite abundant resources.  相似文献   
26.

Background  

Bone resorption displays marked diurnal variation. Reversible inhibition of bone resorption may result in best possible efficacy when bone resorption peaks. The aim of the study was to assess the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of 0.8 mg of oral salmon calcitonin (sCT) and the effect of timing of drug intake.  相似文献   
27.

Introduction

A hallmark of systemic autoimmune diseases like systemic lupus erythematosus (SLE) is the increased expression of interferon (IFN) type I inducible genes, so-called IFN type I signature. Recently, T-helper 17 subset (Th17 cells), which produces IL-17A, IL-17F, IL-21, and IL-22, has been implicated in SLE. As CCR6 enriches for Th17 cells, we used this approach to investigate whether CCR6+ memory T-helper cells producing IL-17A, IL-17F, IL-21, and/or IL-22 are increased in SLE patients and whether this increase is related to the presence of IFN type I signature.

Methods

In total, 25 SLE patients and 15 healthy controls (HCs) were included. SLE patients were divided into IFN type I signature-positive (IFN+) (n = 16) and negative (IFN-) (n = 9) patients, as assessed by mRNA expression of IFN-inducible genes (IFIGs) in monocytes. Expression of IL-17A, IL-17F, IL-21, and IL-22 by CD4+CD45RO+CCR6+ T cells (CCR6+ cells) was measured with flow cytometry and compared between IFN+, IFN- patients and HCs.

Results

Increased percentages of IL-17A and IL-17A/IL-17F double-producing CCR6+ cells were observed in IFN+ patients compared with IFN- patients and HCs. IL-17A and IL-17F expression within CCR6+ cells correlated significantly with IFIG expression. In addition, we found significant correlation between B-cell activating factor of the tumor necrosis family (BAFF)–a factor strongly correlating with IFN type I - and IL-21 producing CCR6+ cells.

Conclusions

We show for the first time higher percentages of IL-17A and IL-17A/IL-17F double-producing CCR6+ memory T-helper cells in IFN+ SLE patients, supporting the hypothesis that IFN type I co-acts with Th17 cytokines in SLE pathogenesis.  相似文献   
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29.

Introduction

Electrocardiogram (ECG) abnormalities in patients with blunt chest trauma are diverse and non-specific, but may be indicative of potentially life-threatening conditions.

Case presentation

We report a rare case of pneumopericardium with extreme ECG abnormalities after blunt chest trauma in a 22-year-old male. The diagnosis was confirmed using computed tomography (CT) scanning. The case is discussed, together with its differential diagnosis and the aetiology of pneumopericardium and tension pneumopericardium.

Conclusion

Pneumopericardium should be distinguished from other pathologies such as myocardial contusion and myocardial infarction because of the possible development of tension pneumopericardium. Early CT scanning is important in the evaluation of blunt chest trauma.  相似文献   
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