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991.
Mostly fed with grass in fresh or conserved form, cattle and other livestock have to cope with silicate defence bodies from plants (phytoliths) and environmental silicates (grit), which abrade tooth enamel and could additionally interact with various salivary proteins. To detect potential candidates for silicate-binding proteins, bovine whole saliva was incubated with grass-derived phytoliths and silicates. Interactions of salivary proteins with pulverized bovine dental enamel and dentine were additionally analysed. After intense washing, the powder fractions were loaded onto 1D-polyacrylamide gels, most prominent adhesive protein bands were cut out and proteins were identified by mass spectrometry within three independent replicates. All materials were mainly bound by bovine odorant-binding protein, bovine salivary protein 30×103 and carbonic anhydrase VI. The phytolith/silicate fraction showed additional stronger interaction with haemoglobin β and lactoperoxidase. Conceivably, the binding of these proteins to the surfaces may contribute to biological processes occurring on them.  相似文献   
992.
SynopsisSevere Acute Respiratory Syndrome Coronavirus2 (SARS-CoV2) provoked alertness globally. Existing pandemic eruption of infections with SARS-CoV2 has been phrased as coronavirus disease 2019 (covid-19). Worldwide pneumonia outburst attributable to new SARS-CoV2 alleged to be originated in Wuhan city of China and has affectation of enormous danger regarding civic wellbeing. As of 11 March 2020, international death toll owing to outburst of new coronavirus was approximately 3,800, and about 110,000 have been declared as confirmed cases. The novel SARS-CoV2 demonstrated competence with respect to human to human communication; therefore depicted exponential intensification of cases. As of March 23, there are 374,513 collective cases of global infections; more than 16,350 deaths and number of recovered cases is 101,554. Now Europe has turn out into new epicenter of lethal coronavirus.More than one third of the covid 19 cases are currently outside China. Presently Italy is one of worst hit countries followed by Spain. The rapid global widespread of novel covid-19 viruses lead to World Health Organization (WHO) to declare outbreak as pandemic. Given to seriousness of present scenario an accurate and rapid classification of noxious pathogenic virus is important which will lend a hand in opting for best fitting drugs. The screening program will aid saving people’s lives and help to put off the pandemic situation. The scientists and researchers should collaborate nationally and internationally to win the battle against novel covid-19. We aimed to represent covid 19 outburst scenario in general and Saudi Arabia in particular. This short review report very briefly highlights covid-19 syndromes; propagation; Middle East outburst, natural products as cure for viral diseases, probable psychosomatic effects, protective measures and Islamic wisdom. SARS-CoV2 is subsequent coronavirus outburst that perturbs Middle East, after SARS-CoV and MERS-CoV which has been originated in kingdom of Saudi Arabia in year 2002 and 2012 respectively. The report covers information and developments till 23rd of March 2020 on basis of current published data and studies published on different scientific web-pages.  相似文献   
993.
The ongoing pandemic of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has placed a substantial strain on the supply of personal protective equipment, particularly the availability of N95 respirators for frontline healthcare personnel. These shortages have led to the creation of protocols to disinfect and reuse potentially contaminated personal protective equipment. A simple and inexpensive decontamination procedure that does not rely on the use of consumable supplies is dry heat incubation. Although reprocessing with this method has been shown to maintain the integrity of N95 respirators after multiple decontamination procedures, information on the ability of dry heat incubation to inactivate SARS-CoV-2 is largely unreported. Here, we show that dry heat incubation does not consistently inactivate SARS-CoV-2-contaminated N95 respirators, and that variation in experimental conditions can dramatically affect viability of the virus. Furthermore, we show that SARS-CoV-2 can survive on N95 respirators that remain at room temperature for at least five days. Collectively, our findings demonstrate that dry heat incubation procedures and ambient temperature for five days are not viable methods for inactivating SARS-CoV-2 on N95 respirators for potential reuse. We recommend that decontamination procedures being considered for the reuse of N95 respirators be validated at each individual site and that validation of the process must be thoroughly conducted using a defined protocol.  相似文献   
994.
995.
In this study, we used the probabilistic models developed by us over the last several years to analyze 158 proteins from coronaviruses in order to determine which protein is more vulnerable to mutations. The results provide three lines of evidence suggesting that the spike glycoprotein is different from the other coronavirus proteins: (1) the spike glycoprotein is more sensitive to mutations, this is the current state of the spike glycoprotein, (2) the spike glycoprotein has undergone more mutations in the past, this is the history of spike glycoprotein, and (3) the spike glycoprotein has a bigger potential towards future mutations, this is the future of spike glycoprotein. Furthermore, this study gives a clue on the species susceptibility regarding different proteins.Figure Predictable and unpredictable portions in coronavirus proteins. The data are presented as median with interquartile range. * the predictable and unpredictable portions in spike glycoprotein group are statistically different from any other protein groups at p<0.05 level, except for hemagglutinin-esterase precursor group. # the predictable and unpredictable portions in spike glycoprotein group are statistically different from hemagglutinin-esterase precursor, membrane protein and nucleocapsid protein groups at p<0.05 level. the predictable and unpredictable portions in spike glycoprotein group are statistically different from hemagglutinin-esterase precursor, and membrane protein groups at p<0.05 level.Electronic Supplementary Material is available for this article if you access the article at .  相似文献   
996.
不同培养基对牛体外受精胚发育率及抗冻性的影响   总被引:6,自引:0,他引:6  
采用M199、SOFaa(aa:Amino Acid)和SOF对牛体外受精卵进行发育培养,比较了三种培养条件下的囊胚发育率、孵化率以及这三种条件下培养出来的囊胚的抗冻能力。在M199和SOFaa处理组,囊胚发育率分别为22.6%和29.0%,孵化率分别为 11.3%和8.1%,两者间无显著差异,但均极显著高于SOF处理组(13.6%,0,P<0.01)。三个处理组的囊胚经冷冻解冻后的存活率分别为78.5%、46.4%和17.3%,孵化率分别为41.9%、23.2%和0,三者间存在极显著差异(P < 0.01)。结果表明,不同的培养液不但影响胚胎发育率,同时也影响胚胎的抗冻能力,M199的培养效果优于SOF,氨基酸能明显提高胚胎发育率及抗冻能力。  相似文献   
997.
利用牛呼吸道合胞体病毒(BRSV)接种牛肺细胞(BL),提取病毒RNA。通过RT-PCR扩增BRSV的核蛋白基因,然后定向克隆到原核表达载体pET30a,获得重组表达质粒pET30a-N。将重组质粒转化表达菌BL21(DE3),经增菌培养和IPTG诱导以及SDS-PAGE和Western blot分析,成功表达出了核蛋白(N),其分子量约为49kDa。为制备BRSV核蛋白的单克隆抗体,用纯化的重组核蛋白免疫BALB/c小鼠,取免疫鼠脾细胞与SP2/0细胞融合。采用以BRSV为检测抗原的间接ELISA筛选阳性细胞克隆,经3次克隆纯化后获得2株稳定分泌抗N特异性MAb的杂交瘤细胞株,分别命名为2D12与4B10。用2D12与4B10杂交瘤细胞株接种BALB/c小鼠制备腹水,采用rN及BRSV包被的ELISA测得的效价分别是1×105和1×106及1×102和1×103。间接ELISA、Western blot、IFA试验表明两株杂交瘤细胞所分泌的MAb具有良好的反应性和特异性。经抗体亚类鉴定D12与4B10均为IgG1/κ。特异性试验表明单抗2D12与4B10均不与牛副流感病毒3型和牛病毒性腹泻病毒反应。所制备的D12与4B10可用于建立检测BRSV病原及抗体的诊断方法。  相似文献   
998.
We report here the discovery of a unique and novel angiotensin binding site and peptide system based upon the C-terminal 3–8 hexapeptide fragment of angiotensin II (NH3+-Val-Tyr-Ile-His-Pro-Phe-COO) (AII(3–8) (AIV)). This fragment binds saturably, reversibly, specifically, and with high affinity to membrane-binding sites in a variety of tissues and from many species. The binding site is pharmacologically distinct from the classic angiotensin receptors (AT1 or AT2) displaying low affinity for the known agonists (AII and AIII) and antagonist (Sar1,Ile8-AII). Although a definitive function has not been assigned to this system in many of the tissues in which it resides, AIV's interaction with endothelial cells may involve a role in endothelial cell-dependent vasodilation. Consequent to this action, AIV is a potent stimulator of renal cortical blood flow.  相似文献   
999.
Methylarginines in free form were identified in bovine brain. Three compounds were isolated from the basic aliphatic amino acid fraction of bovine brain with several ion-exchange chromatographies. They showed the same Rf values in paper and thin-layer chromatographies as those of authentic NG-monomethylarginine, NG,NG-dimethylarginine, and NG,N'G-dimethylarginine. The migration distance of the isolated compounds in high-voltage paper electrophoresis and the retention times in ion-exchange HPLC were also identical to those of the above authentic methylarginines. We concluded that these three compounds are the methyl derivatives of arginine described above. The amount of these three compounds isolated from 1,090 g of bovine brain was 0.3 mumol of NG-monomethylarginine, 0.1 mumol of NG,NG-dimethylarginine, and 0.5 mumol of NG,N'G-dimethylarginine. The occurrence of these free methylarginines may have an important role in regulating the signal transduction through the nitric oxide system.  相似文献   
1000.
A latent, as well as an expressed form of adenylate cyclase coupled to β-adrenergic receptors is present in intact crude synaptosomal preparations from bovine cerebellum. The latent adenylate cyclase activity was assayed in Krebs-Ringer buffer by [3H]adenine labeling and was found to be coupled to a β1-like adrenergic receptor. The externally accessible adenylate cyclase assayed in the same with [3H]ATP was stimulated via β2-adrenergic receptors.  相似文献   
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