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71.
Takami H Nakasone K Ogasawara N Hirama C Nakamura Y Masui N Fuji F Takaki Y Inoue A Horikoshi K 《Extremophiles : life under extreme conditions》1999,3(1):29-34
The nucleotide sequences of three independent fragments (designated no. 3, 4, and 9; each 15–20 kb in size) of the genome
of alkaliphilic Bacillus sp. C-125 cloned in a λ phage vector have been determined. Thirteen putative open reading frames (ORFs) were identified in
sequenced fragment no. 3 and 11 ORFs were identified in no. 4. Twenty ORFs were also identified in fragment no. 9. All putative
ORFs were analyzed in comparison with the BSORF database and non-redundant protein databases. The functions of 5 ORFs in fragment
no. 3 and 3 ORFs in fragment no. 4 were suggested by their significant similarities to known proteins in the database. Among
the 20 ORFs in fragment no. 9, the functions of 11 ORFs were similarly suggested. Most of the annotated ORFs in the DNA fragments
of the genome of alkaliphilic Bacillus sp. C-125 were conserved in the Bacillus subtilis genome. The organization of ORFs in the genome of strain C-125 was found to differ from the order of genes in the chromosome
of B. subtilis, although some gene clusters (ydh, yqi, yer, and yts) were conserved as operon units the same as in B. subtilis.
Received: April 17, 1998 / Accepted: June 23, 1998 相似文献
72.
Detection of tumor marker CA125 in ovarian carcinoma using quantum dots 总被引:11,自引:0,他引:11
The fluorescent labeling of biological materials usingsmall-molecule organic dyes is widely employed in bio-logical imaging and clinical diagnosis. Organic fluoro-phores, however, have certain characteristics that limittheir advantages in some applications. These limitationsinclude narrow excitation bands and broad emissionbands with red spectral tails, which make the simultaneousevaluation of several light-emitting probes difficult due tospectral overlap. Also, many organic dyes exhibit highp… 相似文献
73.
硫酸镁对大鼠海马CA1区神经元钠电流的抑制作用 总被引:5,自引:2,他引:3
利用全细胞膜片钳技术研究了硫酸镁 (MgSO4 )对大鼠海马CA1区神经元钠电流的影响。结果表明 ,MgSO4 可浓度依赖和电压依赖地抑制钠电流 ,半数抑制浓度为 4 0 5mmol/L。这一抑制作用与刺激频率无关。结果还表明 ,4mmol/LMgSO4 不影响钠电流的失活过程 ,却使半数激活电压由 - 5 5 8± 6 8mV变为 - 3 4 2± 6 2mV (n =8,P <0 0 1) ,而激活曲线的斜率因子不变。结果提示 ,MgSO4 抑制大鼠海马CA1区神经元的钠电流可能是其抗缺血缺氧造成的中枢神经系统损伤的机制之一 相似文献
74.
Harada N Himeno A Shigematsu K Sumikawa K Niwa M 《Cellular and molecular neurobiology》2002,22(2):207-226
1. Interaction in the recognition of endothelin-1 (ET-1), a typical bivalent ET receptor-ligand, between ETA and ETB receptors was investigated in the rat anterior pituitary gland, using our quantitative receptor autoradiographic method with tissue sections preserving the cell-membrane structure and ET receptor-related compounds.2. In saturation binding studies with increasing concentrations (0.77–200 pM) of 125I-ET-1 (nonselective bivalent radioligand), 125I-ET-1 binding to the rat anterior pituitary gland was saturable and single with a K
D of 71 pM and a B
max of 120 fmol mg–1. When 1.0 M BQ-123 (ETA antagonist) was added to the incubation buffer, binding parameters were 8.3 pM of K
D and 8.0 fmol mg–1 of B
max, whereas 10 nM sarafotoxin S6c (ETB agonist) exerted little change in these binding parameters (K
D, 72 pM; B
max, 110 fmol mg–1).3. Competition binding studies with a fixed amount (3.8 pM) of 125I-ET-1 revealed that when 1.0 M BQ-123 was present in the incubation buffer, ETB receptor-related compounds such as sarafotoxin S6c, ET-3, IRL1620 (ETB agonist), and BQ-788 (ETB antagonist) competitively inhibited 125I-ET-1 binding with K
is of 140, 18, 350 pM, and 14 nM, respectively, however, these compounds were not significant competitors for 125I-ET-1 binding in the case of absence of BQ-123.4. In cold-ligand saturation studies with a fixed amount (390 pM) of 125I-IRL 1620 (ETB radioligand), IRL1620 bound to a single population of the ETB receptor, and no change was observed in binding characteristics in the presence of 1.0 M BQ-123. 125I-IRL1620 binding was competitively inhibited by ET-1 and ET-3 in the absence of BQ-123, with K
is of 20 and 29 pM, respectively, the affinities being much the same as those of 29 nM, in the presence of 1.0 M BQ-123.5. Two nonbivalent ETA antagonists, BQ-123 and PD151242, were highly sensitive and full competitors for 125I-ET-1 binding (5.0 pM), in the presence of 10 nM sarafotoxin S6c.6. Taken together with the present finding that mRNAs encoding the rat ETA and the ETB receptors are expressed in the anterior pituitary gland, we tentatively conclude that although there are ETA and ETB receptors with a functional binding capability for ET receptor-ligands, the ETB receptor does not independently recognize ET-1 without the aid of the ETA receptor. If this thesis is tenable, then ET-1 can bridge between the two receptors to form an ETA–ETB receptor heterodimer. 相似文献
75.
Ohkura K Lee JD Shimizu H Nakano A Uzui H Horikoshi M Fujibayashi Y Yonekura Y Ueda T 《Molecular and cellular biochemistry》2003,248(1-2):203-208
We previously reported on the use of enzymatic analysis to impair fatty acid metabolism followed by reduced myocardial energy content, leading to severe heart failure in adriamycin (ADR)-treated rats. The aim of this study is to investigate whether impaired myocardial energy metabolism can also be detected by other methods; i.e. measuring mitochondrial complex I activity and myocardial 125I-15-(p-iodophenyl)-3-(R,S)- methylpentadecanoic acid (BMIPP) accumulation in ADR-treated rats. Eight-week-old male Sprague-Dawley rats received 6 intraperitoneal injections of ADR (total 15 mg/kg: group ADR) or saline (control group) over 2 weeks. Left ventricular (LV) ejection fraction was assessed using echocardiography at 3- and 6-weeks after ADR injection (3 weeks and 6 weeks, respectively). Myocardial fatty acid utilization was assessed at 3 weeks and 6 weeks. The myocardial counts of BMIPP were measured after intravenous BMIPP (370 kBq) injection, and 125I counts were measured to calculate the uptake ratio. The enzymatic activity of complex I was assessed by monitoring the oxidation of nicotinamide-adenine-dinucleotide-disodium-salt (NADH). In rats treated with ADR, significant decrease in LV ejection fraction was observed only at 6 weeks compared to control (72.5 vs. 84.5%, p < 0.01rpar;. LV ejection fraction at 3 weeks was identical between group ADR and control (81.8 vs. 84.4%). However, at 3 weeks, complex I activity was already reduced significantly in group ADR as compared to control group (p = 0.03), but the reduction in BMIPP accumulation was not (p = 0.15). Our data indicated that reduced complex I activity in a phenomenon occurred in early phase of ADR-induced cardiomyopathy, and it might play an important role in the progression of ADR-induced heart failure. 相似文献
76.
Bacillus species and other microbes with pH optima for growth higher than pH 9 are defined as alkaliphiles. A large number of alkaliphilic
Bacillus strains producing useful enzymes, have been isolated from various environments. Some of these enzymes, such as proteases
and cellulases from alkaliphilic Bacillus strains, have been commercialized and have brought great advantages to industry and domestic life. To support further development
of the enzyme industry, we initiated analysis of the genome of Bacillus halodurans C-125, which is 4.25 Mb in size, and constructed a physical and genetic map for comparison with the Bacillus subtilis chromosome. Systematic sequencing of the whole genome of Bacillus halodurans C-125 has been automated since the beginning of May 1998, and sequencing of 98% of the whole genome has been done so far.
Through genome analysis, it became apparent that the genome organization of alkaliphilic Bacillus halodurans C-125 is totally different from that of B. subtilis orthologues.
Received: July 11, 1999 / Accepted: December 27, 1999 相似文献
77.
Wild Sicilian Rosemary: Phytochemical and Morphological Screening and Antioxidant Activity Evaluation of Extracts and Essential Oils 下载免费PDF全文
Edoardo M. Napoli Laura Siracusa Antonella Saija Antonio Speciale Domenico Trombetta Teresa Tuttolomondo Salvatore La Bella Mario Licata Giuseppe Virga Raffaele Leone Claudio Leto Laura Rubino Giuseppe Ruberto 《化学与生物多样性》2015,12(7):1075-1094
To identify the best biotypes, an extensive survey of Sicilian wild rosemary was carried out by collecting 57 samples from various sites, followed by taxonomic characterization from an agronomic perspective. All the biotypes collected were classified as Rosmarinus officinalis L. A cluster analysis based on the morphological characteristics of the plants allowed the division of the biotypes into seven main groups, although the characteristics examined were found to be highly similar and not area‐dependent. Moreover, all samples were analyzed for their phytochemical content, applying an extraction protocol to obtain the nonvolatile components and hydrodistillation to collect the essential oils for the volatile components. The extracts were characterized by LC‐UV‐DAD/ESI‐MS, and the essential oils by GC‐FID and GC/MS analyses. In the nonvolatile fractions, 18 components were identified, namely, 13 flavones, two organic acids, and three diterpenes. In the volatile fractions, a total of 82 components were found, with as predominant components α‐pinene and camphene among the monoterpene hydrocarbons and 1,8‐cineole, camphor, borneol, and verbenone among the oxygenated monoterpenes. Cluster analyses were carried out on both phytochemical profiles, allowing the separation of the rosemary samples into different chemical groups. Finally, the total phenol content and the antioxidant activity of the essential oils and extracts were determined with the Folin–Ciocalteu (FC) colorimetric assay, the UV radiation‐induced peroxidation in liposomal membranes (UV‐IP test), and the scavenging activity of the superoxide radical (O$\rm{{_{2}^{{^\cdot} -}}}$ ). The present study confirmed that the essential oils and organic extracts of the Sicilian rosemary samples analyzed showed a considerable antioxidant/free radical‐scavenging activity. 相似文献
78.
目的:分析血清CA199、CYFR21-1、CEA、NSE 水平检测在肺癌诊断及疗效评估中的临床价值,探讨其与肺癌的相关性。方
法:采用化学发光免疫法检测78 例肺癌患者、50 例肺部良性疾病及50 例健康体检者血清CA199、CYFR21-1、CEA、NSE 水平,比
较治疗前后肺癌患者肿瘤标志物水平的变化。结果:肺癌组血清CA199、CYFR21-1、CEA、NSE 水平较对照组、肺良性疾病组均显
著升高(P<0.05);Ⅲ-Ⅳ期肺癌患者各肿瘤标志物水平均较Ⅰ-Ⅱ期患者明显升高(P<0.05);四项联合检测的敏感性为79.5 %,明显
高于CA199、CYFR21-1、CEA、NSE 任一单项肿瘤标志物的敏感性(P<0.05);随着疗效的下降,血清CA199、CYFR21-1、CEA、NSE
水平逐渐升高(P<0.05)。结论:肺癌患者血清CA199、CYFR21-1、CEA、NSE 水平呈高表达状态,且其表达水平与肺癌病情程度密
切相关,联合检测有助于提高肺癌诊断的敏感度及指导治疗方案选择。 相似文献
79.
Uk Lee Young Ran NamJung Sook Ye Kyoung Jin LeeNari Kim Chul Hyun Joo 《Biochemical and biophysical research communications》2014
Hepatitis C virus (HCV) affects 2–3% of the global population. Approximately one-quarter of acute infections cause chronic hepatitis that leads to liver cirrhosis or hepatocellular carcinoma. The major obstacle of current research is the extremely narrow host tropism of HCV. A single HCV strain can replicate in the Huh7 human hepatoma cell line. Huh7 cells can be adapted under selective pressure in vitro to identify host factors that influence viral replication. Here, we extended this strategy to the in vivo condition and generated a series of cell lines by multiple rounds of adaptation in immunocompromised mice. Adaptation increased the cellular resistance to HCV infection. Microarray analyses revealed that the expression levels of several genes were associated with HCV resistance. Notably, up-regulation of the mRNA encoding cysteine-rich secretory protein 3 (CRISP3), a glycoprotein with unknown function that is secreted from multiple exocrine glands, was correlated with HCV resistance. The presence of CRISP3 in the culture medium limited HCV replication at the early phase of infection. 相似文献
80.
Panteha Mirarefi C. Ted Lee Jr. 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(1):106-114
Photoreversible changes in the conformation and enzymatic activity of bovine carbonic anhydrase have been investigated as a function of photoresponsive surfactant concentration and light conditions. The light-responsive surfactant undergoes a photoisomerization from the relatively hydrophobic trans isomer under visible light to the relatively hydrophilic cis isomer upon UV illumination, providing a means to photoreversibly control enzyme–surfactant interactions. Small-angle neutron scattering and dynamic light scattering measurements, along with fluorescence spectroscopy, indicate that carbonic anhydrase unfolds upon addition of the surfactant under visible light, while only a small degree of unfolding is observed under UV light. Therefore, the enzyme is completely inactivated in the presence of the trans surfactant, while 40% of the native activity is preserved under UV light, providing a photoreversible “on/off switch” of enzyme activity. Small-angle neutron scattering data provide details of the in vitro conformational changes of the enzyme in response to the photosurfactant and light, with the enzyme found to aggregate as a result of photosurfactant-induced unfolding. Fourier transform infrared (FT-IR) spectroscopy further provides information on the secondary structure changes of the protein in the presence of photosurfactant. 相似文献