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991.
992.
Muhammad Farooq Hiroyuki Nakai Atsushi Fujimoto Hiroki Fujikawa Asako Matsuyama Naoyuki Kariya Atsuko Aizawa Hiroshi Fujiwara Masaaki Ito Yutaka Shimomura 《Human mutation》2013,34(1):176-183
Generalized pustular psoriasis (GPP) is a rare, potentially life threatening, and aggressive form of psoriasis, which is characterized by sudden onset with repeated episodic skin inflammation leading to pustule formation. Familial GPP is known to be caused by recessively inherited mutations in the IL36RN gene, which encodes interleukin 36 receptor antagonist (IL‐36Ra). In this article, we performed mutation analysis of the IL36RN gene in 14 Japanese patients with GPP, and identified mutations in two of these patients analyzed. One patient was compound heterozygous for mutations c.115+6T>C and c.368C>G (p.Thr123Arg), whereas the other carried compound heterozygous mutations c.28C>T (p.Arg10*) and c.115+6T>C in the IL36RN gene. Expression studies using total RNA from the patients’ skin revealed that the mutation c.115+6T>C resulted in skipping of exon 3, leading to a frameshift and a premature termination codon (p.Arg10Argfs*1). The protein structure analysis suggested that the missense mutation p.Thr123Arg caused misfolding and instability of IL‐36Ra protein. In vitro studies in cultured cells showed impaired expression of the p.Thr123Arg mutant IL‐36Ra protein, which failed to antagonize the IL‐36 signaling pathway. Our data further underscore the critical role of IL36RN in pathogenesis of GPP. 相似文献
993.
Isoshima Daichi Yamashiro Keisuke Matsunaga Kazuyuki Taniguchi Makoto Matsubara Takehiro Tomida Shuta Ota Shinzo Sato Michiyoshi Shimoe Yutaka Kohriyama Tatsuo Arias Zulema Omori Kazuhiro Yamamoto Tadashi Takashiba Shogo 《Odontology / the Society of the Nippon Dental University》2021,109(1):239-249
Odontology - There is no conclusive evidence regarding a causal relationship between periodontitis and atherosclerosis. In this study, we examined the microbiome in the oral cavity and atheromatous... 相似文献
994.
Takahiro Fuchigami Yutaka Sato Yuya Tomita Tetsuya Takano Shin‐ya Miyauchi Yukinori Tsuchiya Taro Saito Ken‐ichiro Kubo Kazunori Nakajima Mitsunori Fukuda Mitsuharu Hattori Shin‐ichi Hisanaga 《Genes to cells : devoted to molecular & cellular mechanisms》2013,18(5):410-424
Reelin‐Dab1 signaling is indispensable for proper positioning of neurons in mammalian brain. Reelin is a glycoprotein secreted from Cajal‐Reztuis cells in marginal zone of cerebral cortex, and its receptors are Apolipoprotein E receptor 2 (ApoER2) or very low density lipoprotein receptor (VLDLR) expressed on migrating neurons. When Reelin binds to ApoER2 or VLDLR, an adaptor protein Dab1 bound to the receptors undergoes Tyr phosphorylation that is essential for Reelin signaling. We reported previously that Cdk5‐p35 phosphorylates Dab1 at Ser400 and Ser491 and the phosphorylation regulates its binding to CIN85, which is an SH3‐containing multiadaptor protein involved in endocytic downregulation of receptor‐tyrosine kinases. However, the interaction of CIN85 with Dab1 has not been addressed in neurons. We examined here a possibility that CIN85 has a role in Reelin signaling. We found nonpho‐sphorylated Dab1‐mediated colocalization of CIN85 with ApoER2. The colocalization of CIN85 with ApoER2 was increased in neurons stimulated with Reelin repeats 3‐6, an active Reelin fragment. The stimulation recruited CIN85 to domains in plasma membrane where it colocalized with ApoER2 and Dab1 and then to EEA1‐labeled early endosomes in the cytoplasm. In addition, Tyr phosphorylation of Dab1 strengthened the binding to CIN85. These results suggest that CIN85 participates in Reelin signaling through the binding to Dab1. 相似文献
995.
Daisuke Sato Go Shinzawa Masataka Kusunoki Tomonao Matsui Hiroyuki Sasaki Zhonggang Feng Atsuyoshi Nishina Takao Nakamura 《Journal of artificial organs》2013,16(3):352-358
Artificial pancreas systems control insulin-mediated glucose uptake. Although these systems are widely used in the clinical setting, they are still fraught with structural and biological problems. The non-insulin mediated glucose uptake (NIMGU) mechanism could be an alternative candidate as a target system for the artificial control of peripheral glucose uptake. Although the sympathetic nervous system is known to be one of the regulators of NIMGU, the effects of peripheral sympathetic activation on glucose uptake have not been well documented. We electrically stimulated a sympathetic nerve fascicle to clarify the possibility of controlling peripheral glucose uptake. A sympathetic signal was microneurographically obtained in the unilateral sciatic nerve in normal (NRML), insulin-resistant high-fat-fed (HFF), and streptozotocin-induced insulin-depleted (STZ) rats, and electrical stimulation was applied via the microelectrode (microstimulation). The microstimulation was also applied to sites other than the sympathetic fascicles in an additional group of normal rats (NSYMP group). The stimulation applied to the sympathetic fibers resulted in an immediate and transient decrease of blood glucose (BG) in the NRML, HFF, and STZ groups, with little change in the plasma insulin. The change in BG level seemed to depend on the basal BG level (NRML < HFF < STZ). In contrast, no reduction in BG was observed in the NSYMP group. These results suggest that microstimulation in the peripheral sympathetic fascicle could enhance glucose uptake in peripheral tissues—independently of insulin function—and show an alternative possibility for controlling glucose uptake. 相似文献
996.
Yoko Shibata Shuichi Abe Sumito Inoue Akira Igarashi Keiko Yamauchi Yasuko Aida Hiroyuki Kishi Keiko Nunomiya Hiroshi Nakano Masamichi Sato Kento Sato Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《International journal of medical sciences》2013,10(11):1530-1536
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men. 相似文献
997.
Hikari Okita Yuna Kato Tatsuki Masuzawa Kosuke Arai Sayuri Takeo Kohei Sato Nobuyuki Mase Takanori Oyoshi Tetsuo Narumi 《RSC advances》2020,10(49):29373
Stereoselective and efficient synthesis of Gly-Gly-type (E)-methylalkene and (Z)-chloroalkene dipeptide isosteres is realized by organocuprate-mediated single electron transfer reduction. The synthetic isosteres can be used in Fmoc-based solid phase peptide synthesis, resulting in the preparation of the 14-mer RGG peptidomimetics containing an (E)-methylalkene or a (Z)-chloroalkene unit.An efficient synthesis of Gly-Gly-type (E)-methylalkene and (Z)-chloroalkene dipeptide isosteres is realized by organocuprate-mediated single electron transfer reduction.Glycylglycine (Gly-Gly) is the smallest dipeptide and has been synthesized by many approaches in the last 100 years.1 Due to its versatile nature and ready availability, glycylglycine has been used as a chemical probe2 and buffer3 in biochemical studies and also as a reagent which can enhance the solubility of overexpressed proteins.4 In addition to the utility of Gly-Gly itself, oligoglycine (oligo-Gly) motifs are notable for being more flexible and less-functionalized than any combination of other amino acids. These features are useful in bioconjugation strategies which link multiple biomolecules without interfering with the function of each biomolecule, allowing synthesis of bioconjugated artificial molecules including dimeric, multi-domain, and fusion proteins.5 The flexibility of oligo-Gly enables the formation of unusual secondary structures of peptides and proteins.6 Thus, the oligo-Gly motif can be found in the biologically important peptides and proteins such as Met/Leu-enkephalin ( and ), the C-terminus of ubiquitin , ctenidin,7 shepherin I,8 and DNA/RNA-binding proteins with repeated sequences related to the various physiological processes via protein–protein and protein–nucleic acids interactions.9 These proteins relate with gene expression, DNA damage signal and apoptosis, however, the detail effects of Gly-Gly with steric and electronic factors to these functions are unknown. Given the importance of oligo-Gly in various fields, non-hydrolyzable peptidomimetics of oligo-Gly could be attractive building blocks for the synthesis of novel bioconjugated molecules and complex peptidomimetics with improved chemical stability and functionality. For example, even the Gly-Gly dipeptide mimic with the tetra-substituted alkene unit replacing the Gly-Gly peptide bond has been shown to promote the β-hairpin formation, and is thus the smallest peptidomimetic that is known to control a peptide structure.10 There are two reports of the synthesis of Gly-Gly-type fluoroalkene dipeptide isosteres.11 However, the poor synthetic access to such molecules has hindered their application to the peptidomimetics. Our long-standing interest in the drug discovery with amide-to-alkene isosteric switching prompted this investigation into the stereoselective synthesis of Gly-Gly-type (E)-methylalkene and (Z)-chloroalkene dipeptide isosteres.In this report, we describe the beginning of our oligo-Gly-based peptidomimetic study with the stereoselective synthesis of Gly-Gly-type (E)-methylalkene and (Z)-chloroalkene dipeptide isosteres and their use in Fmoc-based solid phase peptide synthesis (SPPS). In the first application of isosteres of this type to access complex peptidomimetics, we synthesize 14-mer RGG peptidomimetics containing (E)-methylalkene or (Z)-chloroalkene unit as surrogates for a Gly-Gly peptide bond. These two isosteres were selected because the potentials of both isosteres have not been fully uncovered, though there are several promising examples.12,13 Since the carbonyl oxygen equivalents of those isosteres are similar in their size14 but differ in their electronic properties,15 comparative studies of these isosteres would have the advantage of exploring the role of peptide bonds in terms of their steric and electronic natures. This work also uncovered the unique ability of the Gly-Gly-type (Z)-chloroalkene isostere to induce β-turn structures in the almost unfoled peptides (Fig. 1).Open in a separate windowFig. 1Gly-Gly peptide and its alkene-type peptidomimetics.The main challenges in this study include the stereoselective formation of the (E)-methylalkene and (Z)-chloroalkene moieties as the surrogates of the Gly-Gly trans-peptide bond, together with the control of the olefine isomerization under the condition of the isostere synthesis and Fmoc-based SPPS. There are several synthetic approaches toward tri-substituted alkene-type isosteres, including the Overman rearrangement,13 the SN2′-type opening of alkenylaziridines,12a Cu-mediated CF3-coupling of vinyl iodide,16 and cross-couplings of vinyl stannane.17 Organocuprate-mediated reactions of α,β-unsaturated carbonyl compounds with γ-leaving group(s) are also powerful methods to produce tri-substituted alkene-type isosteres, and are particularly suitable for the stereoselective synthesis of (Z)-fluoroalkene18 and (Z)-chloroalkene isosteres.19The preparation of Gly-Gly-type alkene dipeptide isosteres was facilitated by the organocuprate-mediated SET reduction that was used in the stereoselective formation of the (E)-methylalkene and (Z)-chloroalkene moieties. Scheme 1 shows the synthesis of (E)-methylalkene isosteres (5). A Witting reaction of methacrolein (1) with ethyl (triphenylphosphoranylidene)acetate followed by epoxidation with m-CPBA afforded the alkenyl oxirane (2) which, treated with Gillman reagent (n-Bu2CuLi), produced the allylic alcohol (3) with high E-selectivity. A Mitsunobu reaction of 3 with Ns(Boc)NH and deprotection provided the Gly-Gly-type (E)-methylalkene dipeptide isostere 5 that can be applied to the Fmoc-based SPPS. All reactions leading to the synthesis of 5 were performed on a gram scale.Open in a separate windowScheme 1Synthesis of Gly-Gly-type (E)-methylalkene dipeptide isosteres (5).Synthesis of chloroalkene isostere (14) is shown in Scheme 2. Based on previous results for the successful, efficient synthesis of Val-Xaa-type chloroalkene isosteres,19c we assumed that a similar protocol would allow for the synthesis of 14. However, our attempts revealed that the Gly substrate used has different reactivity and selectivity compared to the other substrates, particularly in the SET reduction step. Consequently, Gly-specific reaction conditions are necessary. The nucleophilic addition of the lithium enolate of methyl dichloroacetate to the N-sulfinylaldimine (7), prepared from (±)-tert-butylsulfinamide (6) and paraformaldehyde and m-CPBA oxidation of 6 gave the N-tert-butylsulfonyl (Bus)-protected α,α-dichloro-β-amino ester (8). Precise control of the amount of DIBAL-H at low temperatures enables the partial reduction of 8, and this is followed by a Horner–Wadsworth–Emmons reaction to produce the corresponding (E)-enoate (9). Initial efforts to apply our established conditions for SET reduction with Me2CuLi identified the poor Z-selectivity of the reaction and also its propensity to form the α-methylated side products 11 and 12 (Open in a separate windowScheme 2Synthesis of Gly-Gly-type (Z)-chloroalkene dipeptide isosteres (14).Reactivity of (E)-enoate (9) with organocupratesa
Open in a separate windowaAll reactions were carried out at −78 °C for 30 min on a 0.25 mmol scale with 4 equiv. of organocuprates in the presence of metal salts.bYield is determined by 1H NMR analysis of the crude mixture utilizing mesitylene as an internal standard.cR = Me.dR = n-Bu.eR = sec-Bu.fR = tert-Bu.With these isosteres in hand, we explored their use in Fmoc-based SPPS for the preparation of peptidomimetics of the 14-mer RGG peptide derived from translocation in lipo-sarcoma/fused in sarcoma (TLS/FUS) related to the RNA processing (Schemes 3 and and44).20 Starting from the Rink Amide ChemMatrix resin, standard Fmoc-based SPPS with DIC/Oxyma for peptide couplings and 20% (v/v) piperidine/DMF for Fmoc removals were performed for the construction of the peptide resin (15). The synthesized isosteres were incorporated into the peptide-chain by HATU/DIPEA in DMF affording the peptide resins 16 and 18. For the synthesis of (E)-methylalkene-type peptidomimetic, deprotection of Ns group with thiophenol/K2CO3 in DMF and chain elongation followed by global deprotection with TFA/m-cresol/thioanisole/H2O (87.5/5/5/2.5, v/v/v/v) provided the desired (E)-methylalkene-type peptidomimetic (17). Synthesis of the (Z)-chloroalkene-type peptidomimetic (19) was achieved using standard conditions. NMR analysis of the purified peptidomimetics revealed that although (Z)-chloroalkene-type peptidomimetic (19) can be purified solely, a trace amount of olefin isomerized compounds of 17, possibly generated under the coupling, is observed as a side product and was difficult to remove from the desired product.21 Since we used a single coupling protocol with HATU for this study, optimization for the coupling without olefin isomerization is likely to be possible.Open in a separate windowScheme 3Synthesis of Gly-Gly-type (E)-methylalkene-type peptidomimetic (17).Open in a separate windowScheme 4Synthesis of (Z)-chloroalkene-type peptidomimetic (19).It has been demonstrated that d-Ala-l-Ala-type (E)-methylalkene isostere sequence shows a higher preference for a type-II′ β-turn than the corresponding (E)-alkene isostere.12a To determine whether amide-to-alkene isosteric switching in Gly-Gly peptide bonds affects the ability of a peptide to form a β-turn structure, CD spectra were obtained for peptidomimetics (17 and 19) in 50 mM Tris–HCl (pH 7.5) with 100 mM KCl (Fig. 2). The native peptide (20) was included as the control. The CD spectra analysis of turn structures has been discussed in the literature, albeit with lower accuracies.22 Although (E)-methylalkene-type peptidomimetic (17) appears to be random coil, the spectra of 19 exhibited a minimal absorbance peak at 202 nm, which is a typical characteristic of a β-turn conformation.20 On the other hand, the peptide 20 appears to form a β-turn conformation slightly. These results indicated that isosteric switching of Gly-Gly peptide bond with a (Z)-chloroalkene unit can induce a β-turn conformation in the secondary structure of peptides and also that the β-turn inducing ability of (Z)-chloroalkene isosteres is superior to that of (E)-methylalkene isosteres. To the best of our knowledge, this is the first example of such drastic structural control effects of (Z)-chloroalkene isosteres on peptides. We speculated that the electronic effects of the chlorine substituent are responsible for the superior β-turn inducing ability. Efforts to determine their biological activity, including DNA/RNA-binding affinity, are currently in progress.Open in a separate windowFig. 2CD spectra of peptidomimetics (17 and 19) and the corresponding native peptide (20). 相似文献
Entry | Conditions | Yieldb (%) | |||
---|---|---|---|---|---|
10-Z | 10-E | 11 | 12 | ||
1 | Me2CuLi | 48 | 19 | 15c | 1c |
2 | n-Bu2CuLi | 55 | 0 | 25d | 20d |
3 | n-Bu2CuLi, HMPA | 0 | 0 | 46d | 13d |
4 | n-Bu2CuLi, NMP | 44 | 0 | 29d | 6d |
5 | n-Bu2CuLi, DMSO | 46 | 7 | 19d | 2d |
6 | sec-Bu2CuLi | 67 | 6 | 27e | 0 |
7 | tert-Bu2CuLi | 74 | 4 | 2f | 0 |
8 | tert-Bu2CuMgCl | 63 | 0 | 0 | 0 |
998.
Norzila Kusnin Nor Azah Yusof Jaafar Abdullah Suriana Sabri Faruq Mohammad Shuhaimi Mustafa Nurul Asyikeen Ab Mutalib Shinobu Sato Shigeori Takenaka Nor Azizah Parmin Hamad A. Al-Lohedan 《RSC advances》2020,10(46):27336
In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of Sus scrofa mitochondrial DNA (mtDNA) in food utilizing a new hybrid indicator, ferrocenylnaphthalene diimide (FND). The morphology and elemental composition of the SiNWs/PtNPs-modified SPCE was analyzed by field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry (CV) was used to study the electrical contact between the PtNPs and the screen-printed working electrode through SiNWs, while electrochemical impedance spectroscopy (EIS) was used to measure the charge transfer resistance of the modified electrode. The results clearly showed that the SiNWs/PtNPs were successfully coated onto the electrode and the effective surface area for the SiNWs/PtNPs-modified SPCE was increased 16.8 times as compared with that of the bare SPCE. Differential pulse voltammetry used for the detection of porcine DNA with FND as an intercalator confirmed its specific binding to the double-stranded DNA (dsDNA) sequences. The developed biosensor showed a selective response towards complementary target DNA and was able to distinguish non-complementary and mismatched DNA oligonucleotides. The SiNWs/PtNPs-modified SPCE that was fortified with DNA hybridization demonstrated good linearity in the range of 3 × 10−9 M to 3 × 10−5 M (R2 = 0.96) with a detection limit of 2.4 × 10−9 M. A cross-reactivity study against various types of meat and processed food showed good reliability for porcine samples.An electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles on a screen-printed carbon electrode for the detection of Sus scrofa mitochondrial DNA in food. 相似文献
999.
1000.
Eisuke Suganuma Hideaki Sakata Nodoka Adachi Satoshi Asanuma Mihoko Furuichi Yoji Uejima Satoshi Sato Tomoya Abe Daigo Matsumoto Ryohei Takahashi Sachi Yamamoto Yutaka Kawano Takashi Arai Tsutomu Oh-ishi 《Journal of infection and chemotherapy》2021,27(2):185-191
ObjectivesValganciclovir (VGCV) has been shown to improve sensorineural hearing loss (SNHL) and neurological outcomes in patients with neonatal symptomatic congenital cytomegalovirus (cCMV) infection. However, reports on the pharmacokinetics, efficacy and safety of oral VGCV are limited. The aim of this study is to evaluate the pharmacokinetics of VGCV for use in the treatment of cCMV.MethodsThis was a single-center, retrospective observational study conducted at Saitama Children's Medical Center in Japan between 2012 and 2017. CMV DNA copy number, maximum plasma VGCV concentration (Cmax), and adverse events (ADEs) during treatment were evaluated.ResultsA total of 26 patients with cCMV who received VGCV were included in this study. The median age at VGCV initiation was 9.5 months (range 0–46). Twenty-one patients (81%) had SNHL at baseline. Of these, five patients (19%) presented with improved SNHL, and none experienced worsened SNHL during treatment. The mean VGCV Cmax was 3.5 μg/mL (range 2–5.3), with no significant variation among individual values, and the values were maintained during treatment. Furthermore, there were no correlations between the Cmax values and age, sex, SNHL improvement or ADEs. Neutropenia (<1000/mm3) was observed in six patients (23%); however, no serious ADEs occurred.ConclusionsVGCV prevented the progression of SNHL without serious ADEs due to its stable pharmacokinetics. This study provides safety and tolerability of VGCV for the treatment of cCMV patients. 相似文献