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831.
Development of biological soil disinfestations in Japan 总被引:9,自引:0,他引:9
Noriaki Momma Yuso Kobara Seiji Uematsu Nobuhiro Kita Akinori Shinmura 《Applied microbiology and biotechnology》2013,97(9):3801-3809
Biological soil disinfestations (BSDs) were developed separately in Japan and in The Netherlands as an alternative to chemical fumigations. In Japan, it was developed based on the knowledge of irrigated paddy rice and upland crop rotation system that was rather tolerant of soil-borne disease development. The methods consist of application of easily decomposable organic matter, irrigation, and covering the soil surface with plastic film, thereby inducing anaerobic (reductive) soil conditions and suppressing many soil-borne pests including fungi, bacteria, nematodes, and weeds. The methods are widely used by organic farmers in the area where residences and agricultural fields are intermingled. To note one advantage of these methods, maintenance of soil suppressiveness to Fusarium wilt of tomato was suggested, while soil treated with chloropicrin became conducive to the disease. Suppression of soil-borne fungal pathogens by BSDs might be attributed to anaerobicity and high temperature, organic acids generated, and metal ions released into soil water. Contributions of respective factors to suppression of respective pathogens might be diverse. Presumably, these factors might vary on the fungal community structure in BSD-treated soil. These factors also work in paddy fields. Therefore, the BSDs developed in Japan are probably a method to raise the efficacy of paddy–upland rotation through intensive organic matter application and through maintenance of a strongly anaerobic (reductive) soil condition. 相似文献
832.
Ayako Masuda Hidekata Yasuoka Takashi Satoh Yuka Okazaki Yukie Yamaguchi Masataka Kuwana 《Arthritis research & therapy》2013,15(4):R74
Introduction
Altered phenotypes of circulating monocytes of patients with systemic sclerosis (SSc) have been reported, but the role of these alterations in the pathogenesis of SSc remains unclear. This study was undertaken to identify molecules that are preferentially expressed by SSc monocytes, and to investigate the roles of these molecules in the pathogenic process of SSc.Methods
We analyzed circulating CD14+ monocytes isolated from 36 patients with SSc and 32 healthy control subjects. The monocytes'' gene expression profiles were assessed by Oligo GEArray® (SABiosciences, Frederic, MA, USA) and semiquantitative or quantitative PCR; their protein expression was evaluated in culture supernatants of unstimulated monocytes by immunoblotting or ELISA, and by immunocytostaining. Monocyte chemoattractant activity of CCL2 was assessed in a TransWell® system (Corning Incorporated, Corning, NY, USA) in the presence or absence of chondroitin sulfate (CS).Results
A step-wise approach to profiling gene expression identified that versican and CCL2 were upregulated in SSc monocytes. Subsequent analysis of proteins expressed in monocyte culture supernatants confirmed enhanced production of versican and CCL2 in SSc monocytes compared with control monocytes. CCL2 bound to CS chains of versican and colocalized with versican in the monocytes'' Golgi apparatus. Finally, CCL2 had a greater ability to mediate monocyte migration when bound to CS chains, because this binding provided efficient formation of CCL2 gradients and protection from protease attack.Conclusion
Circulating monocytes with elevated versican and CCL2 levels may contribute to the fibrotic process in a subset of SSc patients by amplifying a positive feedback loop consisting of versican, CCL2, and the influx of monocytes. 相似文献833.
Aldose reductase ([EC1.1.1.21]: AR) acts on the first step of the polyol metabolic pathway to catalyze the reduction of glucose to sorbitol with NADPH as a coenzyme. Hyperactivity of the pathway in individuals with high blood glucose level is closely related to the onset or progression of diabetic complications. AR inhibitors have therefore been noted as possible pharmacotherapeutic agents for the treatment of diabetic complications. One AR inhibitor has been on the market in Japan, while some potent inhibitors are in clinical trials. Reviewed are the physiological roles of AR, the chemical structures of AR inhibitors, interactions of AR inhibitors with AR using X-ray studies, and the following potencies of AR inhibitors: in vitro activities for AR, in vitro selectivities between AR and aldehyde reductase, their pharmacological effects in vivo, and their effectiveness in clinical trials. Also discussed are directions for the design of future AR inhibitors. 相似文献
834.
Kengo Asami Akiko Inagaki Takehiro Imura Satoshi Sekiguchi Keisei Fujimori Hiroshi Masutani Junji Yodoi Susumu Satomi Noriaki Ohuchi Masafumi Goto 《PloS one》2013,8(8)
Aims
Recent studies suggest that decreasing oxidative stress is crucial to achieve successful islet transplantation. Thioredoxin-1 (TRX), which is a multifunctional redox-active protein, has been reported to suppress oxidative stress. Furthermore, it also has anti-inflammatory and anti-apoptotic effects. In this study, we investigated the effects of TRX on early graft loss after islet transplantation.Methods
Intraportal islet transplantation was performed for two groups of streptozotocin-induced diabetic mice: a control and a TRX group. In addition, TRX-transgenic (Tg) mice were alternately used as islet donors or recipients.Results
The changes in blood glucose levels were significantly lower in the TRX group compared with the TRX-Tg donor and control groups (p<0.01). Glucose tolerance and the residual graft mass were considerably better in the TRX group. TRX significantly suppressed the serum levels of interleukin-1β (p<0.05), although neither anti-apoptotic nor anti-chemotactic effects were observed. Notably, no increase in the 8-hydroxy-2′-deoxyguanosine level was observed after islet infusion, irrespective of TRX administration.Conclusions
The present study demonstrates that overexpression of TRX on the islet grafts is not sufficient to improve engraftment. In contrast, TRX administration to the recipients exerts protective effects on transplanted islet grafts by suppressing the serum levels of interleukin-1β. However, TRX alone appears to be insufficient to completely prevent early graft loss after islet transplantation. We therefore propose that a combination of TRX and other anti-inflammatory treatments represents a promising regimen for improving the efficacy of islet transplantation. 相似文献835.
Noriaki Yoshida Miyo Oda Yoshiaki Kuroda Yuta Katayama Yoshiko Okikawa Taro Masunari Megumu Fujiwara Takashi Nishisaka Naomi Sasaki Yoshito Sadahira Keichiro Mihara Hideki Asaoku Hirotaka Matsui Masao Seto Akiro Kimura Koji Arihiro Akira Sakai 《PloS one》2013,8(11)
Elevated soluble interleukin-2 receptor (sIL-2R) in sera is observed in patients with malignant lymphoma (ML). Therefore, sIL-2R is commonly used as a diagnostic and prognostic marker for ML, but the mechanisms responsible for the increase in sIL-2R levels in patients with B-cell lymphomas have not yet been elucidated. We first hypothesized that lymphoma cells expressing IL-2R and some proteinases such as matrix metalloproteinases (MMPs) in the tumor microenvironment can give rise to increased sIL-2R in sera. However, flow cytometric studies revealed that few lymphoma cells expressed IL-2R α chain (CD25) in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL), and most CD25-expressing cells in the tumor were T-cells. Distinct correlations between CD25 expression on B-lymphoma cells and sIL-2R levels were not observed. We then confirmed that MMP-9 plays an important role in producing sIL-2R in functional studies. Immunohistochemical (IHC) analysis also revealed that MMP-9 is mainly derived from tumor-associated macrophages (TAMs). We therefore evaluated the number of CD68 and CD163 positive macrophages in the tumor microenvironment using IHC analysis. A positive correlation between the levels of sIL-2R in sera and the numbers of CD68 positive macrophages in the tumor microenvironment was confirmed in FL and extranodal DLBCL. These results may be useful in understanding the pathophysiology of B-cell lymphomas. 相似文献
836.
Emiko Oguri Tomio Yamaguchi Hiromi Tsubota Hironori Deguchi Noriaki Murakami 《Ecology and evolution》2013,3(4):753-762
Leucobryum boninense is endemic to the Bonin Islands, Japan, and its related species are widely distributed in Asia and the Pacific. We aimed to clarify the phylogenetic relationships among Leucobryum species and infer the origin of L. boninense. We also describe the utility of the chloroplast trnK intron including matK for resolving the phylogenetic relationships among Leucobryum species, as phylogenetic analyses using trnK intron and/or matK have not been performed well in bryophytes to date. Fifty samples containing 15 species of Leucobryum from Asia and the Pacific were examined for six chloroplast DNA regions including rbcL, rps4, partial 5′ trnK intron, matK, partial 3′ trnK intron, and trnL‐F intergenic spacer plus one nuclear DNA region including ITS. A molecular phylogenetic tree showed that L. boninense made a clade with L. scabrum from Japan, Taiwan and, Hong Kong; L. javense which is widely distributed in East and Southeast Asia, and L. pachyphyllum and L. seemannii restricted to the Hawaii Islands, as well as with L. scaberulum from the Ryukyus, Japan, Taiwan, and southeastern China. Leucobryum boninense from various islands of the Bonin Islands made a monophylic group that was closely related to L. scabrum and L. javense from Japan. Therefore, L. boninense may have evolved from L. scabrum from Japan, Taiwan, or Hong Kong, or L. javense from Japan. We also described the utility of trnK intron including matK. A percentage of the parsimony‐informative characters in trnK intron sequence data (5.8%) was significantly higher than that from other chloroplast regions, rbcL (2.4%) and rps4 (3.2%) sequence data. Nucleotide sequence data of the trnK intron including matK are more informative than other chloroplast DNA regions for identifying the phylogenetic relationships among Leucobryum species. 相似文献
837.
Previous research suggests that deficits in attention-emotion interaction are implicated in schizophrenia symptoms. Although disruption in auditory processing is crucial in the pathophysiology of schizophrenia, deficits in interaction between emotional processing of auditorily presented language stimuli and auditory attention have not yet been clarified. To address this issue, the current study used a dichotic listening task to examine 22 patients with schizophrenia and 24 age-, sex-, parental socioeconomic background-, handedness-, dexterous ear-, and intelligence quotient-matched healthy controls. The participants completed a word recognition task on the attended side in which a word with emotionally valenced content (negative/positive/neutral) was presented to one ear and a different neutral word was presented to the other ear. Participants selectively attended to either ear. In the control subjects, presentation of negative but not positive word stimuli provoked a significantly prolonged reaction time compared with presentation of neutral word stimuli. This interference effect for negative words existed whether or not subjects directed attention to the negative words. This interference effect was significantly smaller in the patients with schizophrenia than in the healthy controls. Furthermore, the smaller interference effect was significantly correlated with severe positive symptoms and delusional behavior in the patients with schizophrenia. The present findings suggest that aberrant interaction between semantic processing of negative emotional content and auditory attention plays a role in production of positive symptoms in schizophrenia. (224 words) 相似文献
838.
Intra-vacuolar reserves of membranes during stomatal closure: the possible role of guard cell vacuoles estimated by 3-D reconstruction 总被引:1,自引:0,他引:1
Tanaka Y Kutsuna N Kanazawa Y Kondo N Hasezawa S Sano T 《Plant & cell physiology》2007,48(8):1159-1169
Stomatal apertures are regulated by morphological changes in guard cells which have been associated with guard cell vacuolar structures. To investigate the contribution of guard cell vacuoles to stomatal movement, we examined the dynamics of vacuolar membrane structures in guard cells and evaluated the changes in vacuolar volumes and surface areas during stomatal movement. Using a transgenic Arabidopsis line expressing green fluorescent protein (GFP)-AtVAM3, we have found that the guard cell vacuolar structures became complicated during stomatal closure with the appearance of numerous intra-vacuolar membrane structures. A three-dimensional (3-D) reconstruction using our originally developed software, REANT (reconstructor and analyzer of 3-D structure), and photobleaching analysis revealed the continuity of the vacuolar structures, even when they appeared to be compartmented in confocal images of closed stomata. Furthermore, calculations of the surface area by REANT revealed an increase in vacuolar surface area during stomatal closure but a decrease in the surface area of the guard cells. Movement of a vital staining dye, FM4-64, to the vacuolar membrane was accelerated during ABA-induced stomatal closure in Vicia faba. These results suggest that the guard cell vacuoles store some portion of the excess membrane materials produced during stomatal closure as intra-vacuolar structures. 相似文献
839.
840.
Shimizu N Kawamoto JK Utani K 《Biochemical and biophysical research communications》2007,359(3):806-810
We used fluorescence in situ hybridization (FISH) to detect c-myc RNA subspecies in human COLO 320DM tumor cells. Although the FISH procedure removed the majority of RNAs from the nucleolus, c-myc RNA continued to be detected in both the nucleoplasm and nucleolus. This finding suggests stable association between c-myc RNA and the nucleolus. Nucleolar accumulation of c-myc RNA appeared to be temporally regulated by cell-cycle progression. Hybridization with exon- and strand-specific RNA probes indicated that the non-protein coding exon 1 plays a novel role in determining the subnuclear localization of c-myc RNA. Antisense RNA targeting exon 2 localized only with nucleoplasmic foci, where it might interact with the sense strand. Thus, c-myc gene expression may be regulated by intranuclear localization of its RNA. 相似文献