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971.
Takahiro Matsumoto Seikou Nakamura Souichi Nakashima Masayuki Yoshikawa Katsuyoshi Fujimoto Tomoe Ohta Azumi Morita Rie Yasui Eri Kashiwazaki Hisashi Matsuda 《Bioorganic & medicinal chemistry letters》2013,23(18):5178-5181
The methanolic extract from the dried rhizomes of Curcuma comosa cultivated in Thailand was found to inhibit melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells. From the methanolic extract, three new diarylheptanoids, diarylcomosols I–III, were isolated together with 12 known diarylheptanoids. Their chemical structures were elucidated on the basis of chemical and physicochemical evidence. The diarylheptanoids inhibited melanogenesis, and several structural requirements of the active constituents for the inhibition were clarified. In particular, (3R)-1,7-bis(4-hydroxyphenyl)-(6E)-6-hepten-3-ol exhibited stronger inhibitory effect [IC50 = 0.36 μM] without inducing cytotoxicity. The biological effect was much stronger than that of a reference compound, arbutin [IC50 = 174 μM]. We conclude that diarylheptanoid analogs are promising therapeutic agents for the treatment of skin disorders. 相似文献
972.
973.
Kitai Y Fukuda H Enomoto T Asakawa Y Suzuki T Inouye S Handa H 《Journal of biotechnology》2011,155(2):251-256
Simian virus 40 (SV40) virus-like particles (VLPs) are efficient nanocarriers for gene delivery. VLPs conjugated to human epidermal growth factor (hEGF) were prepared and the cell selectivity of the VLP was examined using human epithelial carcinoma A431 cells, which overexpress the EGF receptor. The endocytic efficiency was determined by the level of Gaussia luciferase activity from the encapsulated protein in hEGF-conjugated VLPs. EGF receptor-mediated endocytosis of hEGF-conjugated VLPs was significantly increased and was confirmed by fluorescence imaging using mCherry encapsulated in hEGF-conjugated VLPs. These results suggest that VLPs of SV40 conjugated to a specific ligand could be used for cell selective gene delivery. 相似文献
974.
An examination was performed on 16 intraductal proliferative breast lesions diagnosed as intraductal papillomas (IP) or usual ductal hyperplasia (UDH), which were followed up for more than 3 years. An immunohistochemical marker panel combining myoepithelial markers, high-molecular-weight keratin (HMWK) and neuroendocrine markers was used. Two of 11 IP cases were re-evaluated as atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS). These cases developed breast cancer after the first operation. One IP case showed repeated recurrences. None of the other IP and UDH cases had breast cancer or recurrence. The ADH, DCIS and the recurrent IP showing a solid growth lacked myoepithelia, but the recurrent IP expressed HMWK, immunohistochemically. Interestingly, these three lesions were weakly positive for neuroendocrine markers. All other IPs and UDHs, including lesions having solid components, were negative for neuroendocrine markers, and most of them were positive for myoepithelial markers and/or HMWK. A combination of the above immunohistochemical markers seems useful to evaluate intraductal proliferative lesions and to predict their prognosis. In particular, intraductal proliferative lesions with solid components exhibiting positivity for neuroendocrine markers should be followed up carefully to monitor breast cancer risk or recurrence. 相似文献
975.
Capsaicin 4-O-β-xylooligosaccharides were synthesized by a biocatalytic xylosylation using Aspergillus sp. β-xylosidase. Capsaicin was converted into three new capsaicin glycosides, i.e. capsaicin 4-O-β-xyloside, capsaicin 4-O-β-xylobioside, and capsaicin 4-O-β-xylotrioside in 15, 12 and 10% yield, respectively. All products were isolated from the reaction mixtures by preparative HPLC. The structures of the products were determined by NMR spectroscopic method. 相似文献
976.
Tsuji T Higashida C Yoshida Y Islam MS Dohmoto M Koizumi K Higashida H 《Cellular and molecular neurobiology》2011,31(5):663-668
To identify genes required for brain development, we previously performed in vivo RNA interference (RNAi) screening in Drosophila embryos. We identified pebble as a gene that disrupts development of the Drosophila nervous system. Although pebble has been shown to be involved in neuronal development of Drosophila in several screens, the involvement of Ect2, a mammalian ortholog of pebble, in mammalian neuronal development has not been addressed. To examine the role of Ect2 in neuronal differentiation, we performed
Ect2 RNAi in the mouse neuroblastoma × rat glioma NG108-15 cell line. Depletion of Ect2 resulted in an increased proportion
of binucleate cells and morphological differentiation of NG108-15 cells characterized by the outgrowth of neurites. These
morphological changes were correlated with an increased level of acetylcholine esterase mRNA. In addition, expression of Ect2
was decreased in differentiated NG108-15 cells induced by dibutyryl cyclic AMP. These findings indicate that Ect2 negatively
regulates the differentiation of NG108-15 cells and suggest that Ect2 may play a role in neuronal differentiation and brain
development in vivo. 相似文献
977.
Galanin (GAL) is a neuropeptide that is widely expressed in neuroendocrine tissues, including the adenohypophysis. Since GAL
is expressed at higher levels in females, little attention has been paid to the regulation of GAL secretion in males. Here,
we show that testosterone regulates GAL secretion in the adenohypophysis of male rats. Using double immunoelectron microscopy,
we demonstrate that GAL cells possess three types of secretory granule: those with colocalization of GAL and adrenocorticotropic
hormone (ACTH), those with GAL only, and those with ACTH only. The predominant granule type was that containing both GAL and
ACTH, suggesting that GAL and ACTH are secreted at the same time. Indeed, adrenalectomy induced an acute decrease in the number
of both GAL cells and ACTH cells. In contrast, castration resulted in a decrease in the proportion of GAL cells, while the
proportion of ACTH cells remained unchanged. In addition, ACTH-strongly positive and GAL-positive cells were decreased while
ACTH-weakly positive and GAL-negative cells were increased after castration. Testosterone treatment of castrated animals resulted
in restoration of these levels to those of intact and sham operated animals. These results indicated that testosterone regulates
GAL secretion in male animals. 相似文献
978.
Takahiro Ishii Hiroshi Matsuura Kunimitsu Kaya Charles Santhanaraju Vairappan 《Biochemical Systematics and Ecology》2011,39(4-6):864-867
Biochemical Systematics and Ecology, Volume x, Issue x, Pages x–x (dd mm yyyy). A new bisabolane-type sesquiterpenoid from Curcuma domestica. Takahiro Ishii, Hiroshi Matsuura, Kunimitsu Kaya, Charles Santhanaraju Vairappan.Highlights? Chemical constituents of lowland and highland Curcuma domestica of Borneo are reported. ? Three sesquiterpenes and three curcuminoids secondary metabolites were found in common. ? Highland populations contained two additional bisabolane-type sesquiterpenoid metabolites. ? Curcuma domestica is reported as a new source for novel compound, bisacurol B. 相似文献
979.
980.
Inoue Y Tashiro-Yamaji J Hayashi M Kiyonari H Shimizu T Ibata M Yamana H Kubota T Tanigawa N Yoshida R 《Microbiology and immunology》2011,55(6):446-453
Recipient cells migrating into the transplantation site of an allograft recognize histocompatibility antigens on the grafts and are cytotoxic against the grafts. Although the alloreactive immune response is predominantly directed at the major histocompatibility complex (major histocompatibility complex [MHC]; H-2 in mice) class I molecules, the basic mechanisms of allograft rejection (e.g., ligand-receptor interaction) remain unclear, because of the polymorphism and complexity of the MHC. To examine the role of MHC class I molecules in allograft rejection, D(d) , K(d) or D(d) K(d) -transgenic skin or tumor cells we established on a C57BL/6 (D(b) K(b) ) background and transplanted into C57BL/6 mice. Skin grafts from allogeneic (i.e., BALB/c, B10.D2, and BDF1) strains of mice were rejected from C57BL/6 mice on days 12-14 after grafting, whereas isografts were tolerated by these mice. Unexpectedly, skin grafts from D(d) -, K(d) -, and D(d) K(d) -transgenic C57BL/6 mice were rejected on days 12-14 in a transgene expression rate-independent manner from 9/19 (47%), 20/39 (51%), and 12/17 (71%) of C57BL/6 mice, respectively. Similarly, intradermally transplanted allogeneic (i.e., Meth A), but not syngeneic (i.e., EL-4), tumor cells were rejected from C57BL/6 mice; the growth of D(d) - or K(d) -transfected EL-4 cells was delayed by 10-13 days; and 4/10 (40%) of D(d) K(d) -transfected tumor cells were rejected from C57BL/6 mice. These results indicate that D(d) and K(d) genes are equivalent as allogeneic MHC class I genes and that C57BL/6 (D(b) K(b) ) mice reject D(d) -, K(d) -, or D(d) K(d) -transgened skin or tumor cells in a transgene number-dependent, gene expression rate-independent manner. 相似文献