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111.
Payo IM Ongkana N Tohno S Azuma C Minami T Moriwake Y Tohno Y 《Biological trace element research》2007,119(2):103-110
To elucidate compositional changes of the arteries with aging, the authors investigated age-related changes of elements in
the splenic and pulmonary arteries, which supplied blood to contractile organs. After ordinary dissection by medical students
at Nara Medical University was finished, the splenic and pulmonary arteries were resected from the subjects, ranging in age
from 58 to 94 years. The element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was
found that a moderate accumulation of Ca and P occurred in the splenic artery with aging, but it hardly occurred in the pulmonary
artery with aging. Regarding the relationship among elements, the finding that there were significant direct correlations
among the contents of Ca, P, Mg, and Na was commonly obtained in both the splenic and pulmonary arteries. The accumulation
of Ca and P in the splenic artery with aging occurred independently of that in the pulmonary artery. Histologic observation
indicated that a major part of Ca deposits was seen in the middle tunica, but not in the internal tunica. Therefore, the calcification
occurring in the splenic artery belonged to middle sclerosis. 相似文献
112.
We previously reported that reduced platelet endogenous antioxidant enzymes activities are related to the low plasma zinc
level in patients with end-stage renal failure (ESRF). In this study, we attempt to evaluate whether dietary zinc deprivation
reduces the activities of endogenous antioxidant and then enhances oxidative stress in the unstimulated platelet of normal
and 5/6 nephrectomized (Nx) rats because increased platelet oxidative stress is suggested to involve in the incidence of thrombotic
and atherosclerotic diseases. Male Sprague–Dawley rats (n = 48) were fed a zinc-deficient diet and deionized distilled water for 1 week to induce reduction of plasma zinc level. Half
of the rats continued on this diet for 4 weeks as zinc-deplete group, and the other half were maintained on the same diet
but with zinc-supplemented water (120 mg/L zinc sulfate solution) to correct the reduction of plasma zinc level as zinc-replete
group. Half of each group underwent 5/6 Nx, while the other half underwent sham operation. Another 12 normal rats were fed
standard rat chow (containing 23.4% protein and 50 ppm zinc) and drank deionized distilled water as normal control rats. In
zinc-deplete rats including sham-operated and 5/6 Nx rats exhibited lower endogenous antioxidant enzymes activities such as
reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione peroxidase (GPX) and higher malondialdehyde (MDA) levels
than normal control rats in the unstimulated platelets. However, in zinc-replete rats including sham-operated and 5/6 Nx rats
have a normal endogenous antioxidant enzymes activity and normal MDA levels in the unstimulated platelets. We suggest that
in uremia, the low plasma zinc level may be a risk factor for thrombotic and atherosclerotic diseases because it reduces the
activities of endogenous antioxidant enzymes and increases oxidative stress in the unstimulated platelet.
Supported by grant 92-117 from Taipei Veterans General Hospital 相似文献
113.
Mizuno T Takamura-Enya T Watanabe T Hasei T Wakabayashi K Ohe T 《Mutation research》2007,630(1-2):112-121
4-Amino-3,3'-dichloro-5,4'-dinitrobiphenyl (ADDB) is a novel chemical exerting strong mutagenicity, especially in the absence of metabolic activation. In addition to mutagenicity, ADDB may also disrupt the endocrine system in vitro. ADDB may be discharged from chemical plants near the Waka River and could be unintentionally formed via post-emission modification of drainage water containing 3,3'-dichlorobenzidine (DCB), which is a precursor in the manufacture of polymers and dye intermediates in chemical plants. The main purpose of this study was to make a comprehensive survey of the behaviour and levels of ADDB and suspected starting material or intermediates of ADDB, i.e., DCB, 3,3'-dichloro-4,4'-dinitrobiphenyl (DDB), and 4-amino-3,3'-dichloro-4'-nitrobipheny (ADNB) in Waka River water samples. We also postulated the formation pathway of ADDB. Water samples were collected at five sampling sites from the Waka River four times between March 2003 and December 2004. Samples were passed through Supelpak2 columns, and adsorbed materials were then extracted with methanol. Extracts were used for quantification of ADDB and the related chemicals by HPLC on reverse-phase columns; mutagenicity was evaluated in the Salmonella assay using the O-acetyltransferase-overexpressing strain YG1024. High levels of ADDB, DCB, DDB, and ADNB (12.0, 20,400, 134.8, and 149.4ng/L-equivalent) were detected in the samples collected at the site where wastewater was discharged from chemical plants into the river. These water samples also showed stronger mutagenicity in YG1024 both with and without S9 mix than the other water samples collected from upstream and downstream sites. The results suggest that ADDB is unintentionally formed from DCB via ADNB in the process of wastewater treatment of drainage water containing DCB from chemical plants. 相似文献
114.
Functional interactions between the SK2 channel and the nicotinic acetylcholine receptor in enteric neurons of the guinea pig ileum 总被引:1,自引:0,他引:1
The neurotransmitter acetylcholine (ACh) plays a critical role in gastrointestinal function. The role of the small conductance Ca2+ -activated K+ (SK) channel in ACh release was examined using myenteric plexus preparations of guinea pig ileum. Apamin, an inhibitor of the SK channel, significantly enhanced nicotine-induced ACh release, but neither electrical field stimulation- nor 5-hydroxytryptamine-induced ACh release, suggesting that SK channels might be selectively involved in the regulation of nicotine-induced ACh release. Therefore, we investigated the distribution of SK2 and SK3 subunits and the interaction between SK2 channels and nicotinic ACh receptors (nAChRs) in the guinea pig ileum. The immunoreactivity of SK2 subunits was located in enteric neuronal cells. Furthermore, SK2-immunoreactive cells stained with an antibody for choline acetyltransferase, a marker for cholinergic neurons, and with an antibody for the α3/5 subunits of nAChR. In contrast, immunoreactivity of SK3 subunits was not found in enteric neurons. A co-immunoprecipitation assay with Triton X-100-soluble membrane fractions prepared from the ileum revealed an association of the SK2 subunit with the α3/5 subunits of nAChR. These results suggest that SK2 channels negatively regulate the excitation of enteric neurons via functional interactions with nAChRs. 相似文献
115.
Genetic structure of masu salmon (Oncorhynchus masou) populations in Hokkaido, northernmost Japan, inferred from mitochondrial DNA variation 总被引:1,自引:0,他引:1
S. Kitanishi † K. Edo ‡ T. Yamamoto § N. Azuma O. Hasegawa S. Higashi 《Journal of fish biology》2007,71(SC):437-452
Genetic structure of masu salmon Oncorhynchus masou populations in Hokkaido was examined by analysing mtDNA NADH dehydrogenase subunit 5 gene (561 bp) of 382 individuals collected from 12 rivers, in which there were no records of artificial release. Analysis of molecular variance showed that between groups level and between populations within-group level explained each c. 10% of genetic variance. In neighbour-joining tree, four populations located in southern Hokkaido were clustered into a single group; however, other populations did not form any clear clusters. Fu's F S , Tajima's D and a mismatch distribution test indicated a sudden expansion of population in the entire population of Hokkaido and the northernmost population of Chiraibetsu, which was genetically close to the southern Hokkaido group. The Sea of Japan and southern rivers, including those of southern Hokkaido, seem to have served as refugia for masu salmon during glacial periods, and their dispersal and straying in interglacial periods affected the genetic structure of masu salmon populations in Hokkaido. 相似文献
116.
Tetsushi Sadakata Miwa Washida Noriyuki Morita Teiichi Furuichi 《The journal of histochemistry and cytochemistry》2007,55(3):301-311
The family of Ca2+-dependent activator proteins for secretion (CAPS) is involved in dense-core vesicle exocytosis. CAPS1/CADPS1 and CAPS2/CADPS2 have been identified in mammals. CAPS1 regulates catecholamine release from neuroendocrine cells, whereas CAPS2 is involved in the release of brain-derived neurotrophic factor and neurotrophin-3 from cerebellar granule cells. CAPS1 and CAPS2 are predominantly expressed in brain. Here we show the immunohistochemical localization of the CAPS family proteins in various mouse tissues. In the pituitary gland, CAPS1 and CAPS2 were localized to the pars nervosa and the pars intermedia, respectively. In non-neural tissues, CAPS1 was observed in the islets of Langerhans, minor cell types of the spleen and stomach, and medullary cells of the adrenal gland, whereas CAPS2 was present in bronchial epithelial cells, thyroid parafollicular cells, chief cells of the stomach, ductal epithelium of the salivary gland, kidney proximal tubules, and minor cell types of the thymus, spleen, and colon. These results suggest that secretion from distinct cell types in various tissues involves either or both members of the CAPS family. 相似文献
117.
Peripheral tolerance and the qualitative characteristics of autoreactive T cell clones in primary biliary cirrhosis 总被引:1,自引:0,他引:1
Kawano A Shimoda S Kamihira T Ishikawa F Niiro H Soejima Y Taketomi A Maehara Y Nakamura M Komori A Migita K Ishibashi H Azuma M Gershwin ME Harada M 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(5):3315-3324
Primary biliary cirrhosis is characterized by autoreactive T cells specific for the mitochondrial Ag PDC-E2(163-176). We studied the ability of eight T cell clones (TCC) specific for PDC-E2(163-176) to proliferate or become anergic in the presence of costimulation signals. TCC were stimulated with either human PDC-E2(163-176), an Escherichia coli 2-oxoglutarate dehydrogenase mimic (OGDC-E2(34-47)), or analogs with amino acid substitutions using HLA-matched allogeneic PBMC or mouse L-DR53 fibroblasts as APC. Based on their differential responses to these peptides (human PDC-E2(163-176), E. coli OGDC-E2(34-47)) in the different APC systems, TCC were classified as costimulation dependent or independent. Only costimulation-dependent TCC could become anergic. TCC with costimulation-dependent responses to OGDC-E2 become anergic to PDC-E2 when preincubated with mimic, even if costimulation is independent for PDC-E2(163-176). Anergic TCC produced IL-10. One selected TCC could not become anergic after preincubation with PDC-E2(163-176)-pulsed L-DR53 but became anergic using L-DR53 pulsed with PDC-E2 peptide analogs with a substitution at a critical TCR binding site. TCC that only respond to peptide-pulsed PBMC, but not L-DR53, proliferate with peptide-pulsed CD80/CD86-transfected L-DR53; however, anergy was not induced with peptide-pulsed L-DR53 transfected with only CD80 or CD86. These data highlight that costimulation plays a dominant role in maintaining peripheral tolerance to PBC-specific Ags. They further suggest that, under specific circumstances, molecular mimicry of an autoantigen may restore rather than break peripheral tolerance. 相似文献
118.
Murata Y Tsuruzoe K Kawashima J Furukawa N Kondo T Motoshima H Igata M Taketa K Sasaki K Kishikawa H Kahn CR Toyonaga T Araki E 《Biochemical and biophysical research communications》2007,364(2):301-307
Insulin receptor substrate-1 (IRS-1) is the major substrate of both the insulin receptor and the IGF-1 receptor. In this study, we created IRS-1 transgenic (IRS-1-Tg) mice which express human IRS-1 cDNA under control of the mouse IRS-1 gene promoter. In the IRS-1-Tg mice, IRS-1 mRNA expression was significantly increased in almost all tissues, but its protein expression was increased in very limited tissues (epididymal fat and skeletal muscle). IRS-1-Tg mice showed glucose intolerance and significantly enlarged epididymal fat mass, as well as elevated serum TNF-α concentrations. Importantly insulin signaling was significantly attenuated in the liver of IRS-1-Tg mice, which may contribute to the glucose intolerance. Our results suggest that excess IRS-1 expression may not provide a beneficial impact on glucose homeostasis in vivo. 相似文献
119.
120.
Nakanishi J Wada Y Matsumoto K Azuma M Kikuchi K Ueda S 《Cancer immunology, immunotherapy : CII》2007,56(8):1173-1182
PURPOSE: The programmed death-1 (PD-1)/B7-H1 (also called PD-L1) pathway negatively regulates T cell activation and has been suggested to play an important role in regulating antitumor host immunity. To investigate the clinical significance of B7-H1 expression to the tumor grade and postoperative prognosis of patients with urothelial cancer, we analyzed the relationship between B7-H1 expression and various clinicopathological features and postoperative prognosis. EXPERIMENTAL DESIGN: Sixty-five urothelial cancer cases were examined. B7-H1 expression in tumors and the numbers and phenotypes of tumor-infiltrating lymphocytes were evaluated by immunohistochemistry and flow cytometry. RESULTS: A substantial expression of B7-H1 was observed in all urothelial cancers investigated. Tumor specimens from patients with higher WHO grade or primary tumor classifications showed significantly higher percentages of tumor-associated B7-H1. Tumor-associated B7-H1 expression was significantly associated with a high frequency of postoperative recurrence and poor survival rate. Furthermore, multivariate analysis indicated that tumor-associated B7-H1 was more significant prognostic factor than WHO grade. CONCLUSIONS: Our results demonstrate that the aberrant expression of B7-H1 in urothelial cancer is associated with aggressive tumors, suggesting a regulatory role of tumor-associated B7-H1 in antitumor immunity. Therefore, the manipulation of tumor-associated B7-H1 may become a beneficial target for immunotherapy in human urothelial cancer. 相似文献