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821.
Shinya Yamada Taka-Aki Miyagawa Ren Yamada Hatsumi Shiratori-Takano Noboru Sayo Takao Saito Hideaki Takano Teruhiko Beppu Kenji Ueda 《Applied microbiology and biotechnology》2013,97(14):6223-6230
To develop an efficient bioconversion process for amides, we screened our collection of Streptomyces strains, mostly obtained from soil, for effective transformers. Five strains, including the SY007 (NBRC 109343) and SY435 (NBRC 109344) of Streptomyces sp., exhibited marked conversion activities from the approximately 700 strains analyzed. These strains transformed diverse amide compounds such as N-acetyltetrahydroquinoline, N-benzoylpyrrolidine, and N-benzoylpiperidine into alcohols or N,O-acetals with high activity and regioselectivity. N,O-acetal was transformed into alcohol by serial tautomerization and reduction reactions. As such, Streptomyces spp. can potentially be used for the efficient preparation of hydroxy amides and aminoalcohols. 相似文献
822.
823.
Shinya Yamada Hikaru Shimada Ren Yamada Hatsumi Shiratori-Takano Noboru Sayo Takao Saito Hideaki Takano Teruhiko Beppu Kenji Ueda 《Biotechnology letters》2014,36(3):595-600
An effective preparation scheme for optically-active 3-pyrrolidinol and its derivatives based on biological transformation is proposed. Aspergillus sp. NBRC 109513 hydroxylated 1-benzoylpyrrolidine, yielding (S)-1-benzoyl-3-pyrrolidinol with 66 % ee. Kinetic resolution of 1-benzoyl-3-pyrrolidinol by Amano PS-IM lipase formed optically-active 1-benzoyl-3-pyrrolidinol with >99 % ee. (S)-1-Benzoyl-3-pyrrolidinol was successfully converted to 3-pyrrolidinol and its derivatives with by chemical reactions (>99 % ee). 相似文献
824.
825.
Ariyasu T Tanaka T Fujioka N Yanai Y Yamamoto S Yamauchi H Ikegami H Ikeda M Kurimoto M 《In vitro cellular & developmental biology. Animal》2005,41(1-2):50-56
Summary Interferon-alpha (IFN-α) has recently been shown to modulate in vitro T helper (Th) 1-driven responses in the peripheral blood
mononuclear cells (PBMC) of patients with hepatitis B virus or C virus infection. In this study, we examined the in vitro
effects of IFN-α subtypes (IFN-α1, −α2, −α5, −α8, and −α10) on the Th1/Th2 balance in PBMC obtained from patients with hepatitis
virus infection-associated liver disorders and chronic hepatitis (CH), in comparison with the effect on healthy control volunteer
PBMC. The Th1-type cell percentages and Th1/Th2 ratios were significantly higher in the PBMC of patients when compared with
controls both before and after cultivation in vitro, with the IFN-α subtypes. The IFNα-5 induced an increase in the Th2-type
cell percentages in both control and patient PBMC, resulting in that IFN-α5 lowered the Th1/Th2 ratio in patients with CH.
Furthermore, statistical analysis revealed that IFN-α8 significantly promoted an increase in the Th1/Th2 ratios of PBMC from
patients with CH and liver cirrhosis (LC) but not that of PBMC from patients with LC-hepatocellular carcinoma (HCC) and HCC.
These findings imply that hepatitis virus infection and its disease status modify the effects of IFN-α subtypes on Th1 and
Th2 immune balance in patients. Our findings should help to elucidate the mechanisms underlying successful IFN therapy for
hepatitis virus infection and prevention of hepatocellular carcinogenesis. 相似文献
826.
The distribution and relative proportions of neuropeptide Y (NPY)- and [Met]enkephalyl-Arg-Gly-Leu (ME-RGL)-containing sympathetic neurones in the rat superior cervical ganglion (SCG) and their projections to submaxillary lymph nodes (SLN) were determined by retrograde tracing and immunocytochemistry. Three subpopulations of neurones were detected in the SCG: 64% contained NPY, 30% contained ME-RGL, and 6% were immunonegative for both. Immunoreactive neurones were also present inside the external carotid nerve of the SCG. An injection of Fluoro-Gold (FG) into the left SLN retrogradely labeled a few neurones in the ipsilateral SCG. FG-labeled neurones contained tyrosine hydroxylase (TH) and were either positive for ME-RGL or for NPY. FG-labeled neurones immunostained for ME-RGL outnumbered by 4:1 FG-labeled neurones immunopositive for NPY. It is suggested that the sympathetic/peptidergic innervation to SLN may have distinct vasoregulatory and immunomodulatory functions. 相似文献
827.
Possible immunological differences between monkey and human prostate gland proteins and also between seminal vesicle proteins of these species were investigated by agarose gel electrophoresis, agarose gel immunoelectrophoresis and by the agar gel immunodiffusion method, using anti-sera against human plasma, human seminal plasma and human prostatic acid phosphomonoesterase (PMEase). At the same time, the electrophoretic mobility of these prostatic acid PMEases was compared by means of starch gel electrophoresis.Each of these two tissues, monkey and human, was found to contain antigenic proteins with immunological identity. Though antigenic similarity of monkey and human prostatic acid PMEase was demonstrated by immunological methods, a clear difference was observed in the electrophoretic mobility of these enzymes when examined by starch gel electrophoresis. 相似文献
828.
829.
Takashi Ueyama Tomohiro Donishi Satoshi Ukai Yorihiko Ikeda Muneki Hotomi Noboru Yamanaka Kazuhiro Shinosaki Masaki Terada Yoshiki Kaneoke 《PloS one》2013,8(6)
Subjective tinnitus is characterized by the perception of phantom sound without an external auditory stimulus. We hypothesized that abnormal functionally connected regions in the central nervous system might underlie the pathophysiology of chronic subjective tinnitus. Statistical significance of functional connectivity (FC) strength is affected by the regional autocorrelation coefficient (AC). In this study, we used resting-state functional MRI (fMRI) and measured regional mean FC strength (mean cross-correlation coefficient between a region and all other regions without taking into account the effect of AC (rGC) and with taking into account the effect of AC (rGCa) to elucidate brain regions related to tinnitus symptoms such as distress, depression and loudness. Consistent with previous studies, tinnitus loudness was not related to tinnitus-related distress and depressive state. Although both rGC and rGCa revealed similar brain regions where the values showed a statistically significant relationship with tinnitus-related symptoms, the regions for rGCa were more localized and more clearly delineated the regions related specifically to each symptom. The rGCa values in the bilateral rectus gyri were positively correlated and those in the bilateral anterior and middle cingulate gyri were negatively correlated with distress and depressive state. The rGCa values in the bilateral thalamus, the bilateral hippocampus, and the left caudate were positively correlated and those in the left medial superior frontal gyrus and the left posterior cingulate gyrus were negatively correlated with tinnitus loudness. These results suggest that distinct brain regions are responsible for tinnitus symptoms. The regions for distress and depressive state are known to be related to depression, while the regions for tinnitus loudness are known to be related to the default mode network and integration of multi-sensory information. 相似文献
830.
Teruo Tanaka Kenji Sakaguchi Noboru Ōtake Hiroshi Yonehara 《Bioscience, biotechnology, and biochemistry》2013,77(1):100-103
A screening method for the antibiotics capable of inhibiting synthesis of nucleic acid in bacterial cells or mammalian tumor cells was investigated. The DNA and RNA syntheses in Bacillus subtilis 168 thymine?, indole? were studied by the assay of incorporations of 3H-thymine and 14C-uracil into the cells, respectively. With known antibiotics against nucleic acid synthesis, the adequacy of the method was examined, and the result proved that this method is more sensitive and specific than the conventional assay methods.It was found as a new fact that cellocidin is a potent and specific inhibitor to the thymine incorporation into DNA.By an almost similar procedure, an inhibitory effect of several antibiotics on the incorporations of 3H-thymidine and 14C-uridme into Ehrlich ascites carcinoma cells was also studied. 相似文献