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101.
MethodsDNA was prepared from subjects who participated in the fourth survey of the Tromsø Study in 1994-1995 and who were registered with the endpoints myocardial infarction (MI), type 2 diabetes (T2DM), cancer or death as well as a randomly selected control group. The endpoint registers were complete up to 2010- 2013. Genotyping was performed for rs7041 and rs4588 and serum 25-hydroxyvitamin D (25(OH)D) was measured.ResultsGenotyping for rs7041 and rs4588 was performed successfully in 11 704 subjects. Among these, 1660 were registered with incident MI, 958 with T2DM, 2410 with cancer and 4318 had died. Subjects with the DBP phenotype 1f/1f had 23 – 26 % reduced risk of incident cancer compared to the 1s/1s and 2/2 phenotypes (P < 0.02, Cox regression with gender as covariate). Differences in serum 25(OH)D levels could not explain the apparent cancer protective effect of the DBP variant 1f. In addition to cancer and 25(OH)D, there were significant associations between DBP phenotype and body height, hip circumference and serum calcium.ConclusionThere are important biological differences between the common DBP phenotypes. If the relation between the DBP variant 1f and cancer is confirmed in other studies, determination of DBP phenotype may have clinical importance.  相似文献   
102.
103.
The size and microscopic structure of the spleen of the migratory pied flycatcher (Ficedula hypoleuca) show marked changes during the reproductive cycle. Upon the spring return to their northern breeding sites, the birds have a small spleen with little lymphoid activity and a poorly developed red pulp. During the breeding period the volume of red and white pulp increases, the number and distinctness of lymphoid follicles (germinal centres) in the white pulp increase, and groups of cells with intensely basophilic cytoplasm, probably B cells (plasma cells), appear. The findings suggest that the immune system of the adult pied flycatcher is activated during periods when it is bound to the nest. Young flycatchers beginning their autumn migration also show a marked increase of lymphoid activity in the spleen.  相似文献   
104.
In previous glasshouse experiments, the soilbacterium Serratia plymuthica, strainA153, showed strong growth-suppressingactivities against a range of broad-leavedweeds after foliar spraying. In field tests ofthis strain in spring wheat, spring barley andpotatoes, variable effects were achieved on arange of weeds including Chenopodiumalbum, Stellaria media, Polygonumconvolvulus and Galeopsis speciosa. Atone site, good suppression of C. albumwas observed when the strain was applied in atank mix with another bacterial isolate or withreduced doses of a herbicide. Effects on weedsappeared to be independent of the applicationvolume (1000, 600, 500 l ha–1), but weedswere in some cases more strongly suppressed athigher bacterial doses. Barley yields weresomewhat reduced by the bacterial application,but wheat yields were less affected. AlthoughS. plymuthica suppressed certain weedswhen applied in the field in a simple aqueousformulation and with conventional sprayingequipment, the level of weed suppression wasunsatisfactory from a practical standpoint.  相似文献   
105.
Small, macroscopically visible cysts on the surface of the kidneys were observed in eight 6–8-week-old puppies diagnosed with renal cystadenocarcinoma and nodular dermatofibrosis (RCND). Histologic examination of the renal cortices in these puppies reveals numerous small cystic tubular changes. Hyperplastic change of the epithelial lining of cysts is frequently observed. By laser-capture microdissection we have sampled epithelial cells from such early renal cystic lesions in eight paternal half-sibs diagnosed with RCND. DNA was obtained from the laser-captured material, and all coding exons of the germline-mutated FLCN gene were sequenced to detect putative second hits. Samples from 31 independent hyperplastic epithelial cell sections of tubular microcysts of the RCND siblings were examined as well as normal control samples of the tissue sections. Loss of heterozygosity was detected in 35% of the transformed samples. The frequently observed loss of heterozygosity at the FLCN locus in atypical epithelial cells lining the cysts suggests that loss of heterozygosity/function of the FLCN gene may contribute to neoplastic transformation of renal epithelial cells at a very early age of RCND-affected dogs. The transformed renal epithelial cells seem to grow slowly in young puppies, which indicates that other mutational events are required for the development of tumors in adult dogs.  相似文献   
106.

Introduction

Collagen-induced arthritis (CIA) in mice is a commonly used experimental model for rheumatoid arthritis (RA). We have previously identified a significant quantitative trait locus denoted Cia40 on chromosome 11 that affects CIA in older female mice. This locus colocalizes with another locus, denoted Pregq2, known to affect reproductive success. The present study was performed to evaluate the role of the Cia40 locus in congenic B10.Q mice and to identify possible polymorphic candidate genes, which may also be relevant in the context of RA.

Methods

Congenic B10.Q mice carrying an NFR/N fragment surrounding the Cia40/Pregq2 loci were created by 10 generations of backcrossing (N10). The congenic mice were investigated in the CIA model, and the incidence and severity of arthritis as well as the serum levels of anti-collagen II (CII) antibodies were recorded.

Results

Significant effects on onset, incidence, severity, and anti-CII antibody titers were observed in female mice carrying a heterozygous congenic Cia40/Pregq2 fragment of NFR/N origin, containing one or more polymorphic genes. Congenic male mice did not show increased incidence of CIA, but males carrying a heterozygous fragment showed a significant increase in severity in comparison with wildtype B10.Q males (littermates).

Conclusion

The Cia40/Pregq2 locus at chromosome 11 contains one or more polymorphic genes of NFR/N origin that significantly influence both incidence and severity of CIA in heterozygous congenic mice of the B10.Q strain. The major polymorphic candidate genes for the effects on CIA are Cd79b, Abca8a, and Map2k6. The congenic fragment also contains polymorphic genes that affect reproductive behavior and reproductive success. The Sox9 gene, known to influence sex reversal, is a candidate gene for the reproductive phenotype.  相似文献   
107.
This study was designed to assess whether pre-spawning maternal cortisol administration and an additional stressor, here modelled by mild hyperthermia experienced during incubation, affected the behavioural responses of farmed Atlantic salmon (Salmo salar) offspring when exposed to a novel environment. Mature females were injected prior to stripping with 0, 50 or 100 mg/kg cortisol. After fertilization the eggs were kept at incubation temperatures of either 8 or 10 °C. Four months after hatching, the fish were introduced to a novel environment, i.e. an aquarium (38 l). In each trial two individuals originating from different exposure groups were video recorded and their activity (number of turns, time spent not swimming, time spent at the bottom) and feeding behaviour were measured. Maternal cortisol increased time spent non-swimming and also time spent at the bottom, while cortisol and temperature together additionally affected number of turns. To the best of our knowledge this study is the first in fish to demonstrate a possible link between the maternal endocrinological state at spawning and the offspring's behavioural reactivity to novel situations.  相似文献   
108.

Objective

IL-25 has been implicated in the initiation of type 2 immunity and in the protection against autoimmune inflammatory diseases. Recent studies have identified the novel innate lymphoid type 2 cells (ILC2s) as an IL-25 target cell population. The purpose of this study was to evaluate if IL-25 has any influence on atherosclerosis development in mice.

Methods and Results

Administration of 1 μg IL-25 per day for one week to atherosclerosis-prone apolipoprotein (apo)E deficient mice, had limited effect on the frequency of T cell populations, but resulted in a large expansion of ILC2s in the spleen. The expansion was accompanied by increased levels of anti-phosphorylcholine (PC) natural IgM antibodies in plasma and elevated levels of IL-5 in plasma and spleen. Transfer of ILC2s to apoE deficient mice elevated the natural antibody-producing B1a cell population in the spleen. Treatment of apoE/Rag-1 deficient mice with IL-25 was also associated with extensive expansion of splenic ILC2s and increased plasma IL-5, suggesting ILC2s to be the source of IL-5. Administration of IL-25 in IL-5 deficient mice resulted in an expanded ILC2 population, but did not stimulate generation of anti-PC IgM, indicating that IL-5 is not required for ILC2 expansion but for the downstream production of natural antibodies. Additionally, administration of 1 μg IL-25 per day for 4 weeks in apoE deficient mice reduced atherosclerosis in the aorta both during initiation and progression of the disease.

Conclusions

The present findings demonstrate that IL-25 has a protective role in atherosclerosis mediated by innate responses, including ILC2 expansion, increased IL-5 secretion, B1a expansion and natural anti-PC IgM generation, rather than adaptive Th2 responses.  相似文献   
109.
The isolated cathepsin D-like enzyme from Atlantic cod (Gadus morhua L.) liver was shown to be a monomer with a molecular mass of approximately 40 kDa. It was inhibited by Pepstatin A and had an optimum for degradation of haemoglobin at pH 3.0. The purified enzyme had lower temperature stability than bovine cathepsin D. Antibodies raised against the purified enzyme and against two C-terminal peptides of cod cathepsin D recognized a 40 kDa protein in immunoblotting of the samples from the purification process. Both antisera showed cross reactivity with a similar sized protein in liver from cod, saithe (Pollachius virens L.), Atlantic herring (Clupea harengus L.) and Atlantic salmon (Salmo salar L.). A protein of same size was detected in wolffish (Anarhichas lupus L.) liver with the antibody directed against the purified enzyme. This antibody also recognized the native enzyme and detected the presence of cathepsin D in muscle of cod, saithe, herring and salmon. These antibodies may be useful in understanding the mechanisms of post mortem muscle degradation in fish by comparing immunohistochemical localization and enzyme activity, in particular in cod with different rate of muscle degradation. They may also be used for comparing muscle degradation in different fish species.  相似文献   
110.
Nonproductive infection of B lymphocytes by Epstein-Barr virus (EBV) is associated with a highly restricted expression of viral genes. In growth-transformed lymphoblastoid cell lines, the products of these genes include a complex of at least six EBV nuclear antigens (EBNAs) (EBNA-1 through EBNA-6) and one membrane protein (latent membrane protein [LMP]). EBV-carrying Burkitt's lymphoma (BL) biopsies and derived cell lines that have retained a representative phenotype (group I BL lines) express only EBNA-1 (M. Rowe, D. T. Rowe, C. D. Gregory, L. S. Young, P. J. Farrell, H. Rupani, and A. B. Rickinson, EMBO J. 6:2743-2751, 1987). We have found that EBNA-2 through EBNA-6 and LMP can be up regulated by treating the group I BL line Rael with the DNA-demethylating agent 5-azacytidine (5-AzaC). The drug acted in a time- and dose-dependent manner. EBNA-2-positive cells were detected by anti-complement immunofluorescence staining just 12 h after addition of 4 microM 5-AzaC and reached a maximum number at 72 h, when up to 75% of the population was positive. EBNA-2, EBNA-3, EBNA-4, EBNA-4, EBNA-6, and LMP were demonstrated immunoblots starting at 48 h. The EBV-encoded early antigens and viral capsid antigens were also induced but at a lower level. EBNA-2 and the lytic cycle-associated antigens appeared with a different time course and in largely nonoverlapping cell subpopulations, as demonstrated by double fluorescence staining. Thus, EBNA-2 expression was not restricted to lytically infected cells, nor was EBNA-2 required for entry into the lytic cycle. The coding and regulatory sequences of EBNA-2 and LMP were found to be highly methylated in Rael cells and were, as expected, demethylated after 5-AzaC treatment. These findings suggest that DNA methylation may participate in the regulation of growth transformation-associated viral genes in BL cells.  相似文献   
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