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61.
Novel mutations of the PKD1 gene in Korean patients with autosomal dominant polycystic kidney disease 总被引:2,自引:0,他引:2
Kim UK Jin DK Ahn C Shin JH Lee KB Kim SH Chae JJ Hwang DY Lee JG Namkoong Y Lee CC 《Mutation research》2000,432(1-2):39-45
The gene for the most common form of autosomal dominant polycystic kidney disease (ADPKD), PKD1, has recently been characterized and shown to encode an integral membrane protein, polycystin-1, which is involved in cell-cell and cell-matrix interactions. Until now, approximately 30 mutations of the 3' single copy region of the PKD1 gene have been reported in European and American populations. However, there is no report of mutations in Asian populations. Using the polymerase chain reaction and single-strand conformation polymorphism (SSCP) analysis, 91 Korean patients with ADPKD were screened for mutation in the 3' single copy region of the PKD1 gene. As a result, we have identified and characterized six mutations: three frameshift mutations (11548del8bp, 11674insG and 12722delT), a nonsense mutation (Q4010X), and two missense mutations (R3752W and D3814N). Five mutations except for Q4010X are reported here for the first time. Our findings also indicate that many different mutations are likely to be responsible for ADPKD in the Korean population. The detection of additional disease-causing PKD1 mutations will help in identifying the location of the important functional regions of polycystin-1 and help us to better understand the pathophysiology of ADPKD. 相似文献
62.
Manoharan K Chae HS Cha JM Cho SH Shin SH Cho BH Lee WS 《Plant & cell physiology》2000,41(10):1143-1148
When carrot suspension cells were cultured on medium containing no carbon source (starvation), the levels of phosphatidylserine (PS) increased transiently 3-4 d after the initiation of starvation while levels of most other phospholipid (PL) species decreased. We previously reported that fatty acids of these PLs served as an alternative carbon source during starvation. The present study showed that cells possess two different biosynthetic pathways involving phosphatidylcholine (PC)/phosphatidylethanolamine (PE) exchange enzymes and PS synthase to synthesize PS. These activities peaked similarly 4 d after the initiation of starvation and coincided with the peak of PS level. The synthesis of serine was also significantly activated during starvation. The activity of phosphoserine aminotransferase (PSAT) which is involved in serine synthesis increased with a time course similar to that of the increase in the PS level. These observations suggest that the increase in PS level plays an important role in membranes which are degraded during starvation. 相似文献
63.
64.
Background
Inhibition and eradication of Staphylococcus aureus biofilms with conventional antibiotic is difficult, and the treatment is further complicated by the rise of antibiotic resistance among staphylococci. Consequently, there is a need for novel antimicrobials that can treat biofilm-related infections and decrease antibiotics burden. Natural compounds such as eugenol with anti-microbial properties are attractive agents that could reduce the use of conventional antibiotics. In this study we evaluated the effect of eugenol on MRSA and MSSA biofilms in vitro and bacterial colonization in vivo.Methods and Results
Effect of eugenol on in vitro biofilm and in vivo colonization were studied using microtiter plate assay and otitis media-rat model respectively. The architecture of in vitro biofilms and in vivo colonization of bacteria was viewed with SEM. Real-time RT-PCR was used to study gene expression. Check board method was used to study the synergistic effects of eugenol and carvacrol on established biofilms. Eugenol significantly inhibited biofilms growth of MRSA and MSSA in vitro in a concentration-dependent manner. Eugenol at MIC or 2×MIC effectively eradicated the pre-established biofilms of MRSA and MSSA clinical strains. In vivo, sub-MIC of eugenol significantly decreased 88% S. aureus colonization in rat middle ear. Eugenol was observed to damage the cell-membrane and cause a leakage of the cell contents. At sub-inhibitory concentration, it decreases the expression of biofilm-and enterotoxin-related genes. Eugenol showed a synergistic effect with carvacrol on the eradication of pre-established biofilms.Conclusion/Major Finding
This study demonstrated that eugenol exhibits notable activity against MRSA and MSSA clinical strains biofilms. Eugenol inhibited biofilm formation, disrupted the cell-to-cell connections, detached the existing biofilms, and killed the bacteria in biofilms of both MRSA and MSSA with equal effectiveness. Therefore, eugenol may be used to control or eradicate S. aureus biofilm-related infections. 相似文献65.
Purification of anti‐colorectal cancer monoclonal antibody CO17‐1A from insect cell culture using a French press and sonication 下载免费PDF全文
Monoclonal antibody (mAb) CO17‐1A binds to GA733, which is a tumor‐associated glycoprotein antigen highly expressed on the colorectal cancer cell surface. Thus, mAb CO17‐1A is considered a useful biomolecule for diagnosis and treatment against colorectal cancer. Previously, we established a baculovirus–insect cell expression system for the production of mAb CO17‐1A. In order to use mAb CO17‐1A as a diagnostic and therapeutic tool, however, the antibody must be properly purified from the insect cells. In this study, our aim was to investigate effective purification processes of mAb CO17‐1A expressed in Spodoptera frugiperda (Sf9) insect cells, using a French press and sonication for cell disruption. SDS‐PAGE confirmed that both mAb CO17‐1A and mAb CO17‐1A fused to the KDEL endoplasmic reticulum (ER) retention signal (mAb CO17‐1AK) were expressed clearly in Sf9 insect cells. Western blot analysis showed that detection levels of mAb CO17‐1A and CO17‐1AK were higher when the insect cells were disrupted two times by the French press and then sonicated, compared to only one French press disruption plus sonication. Optical microscopy confirmed that insect cells treated with both the French press and sonication were properly disrupted. Analysis of gene sequence information on mAb CO17‐1A verified that a signal peptide is present but a transmembrane protein does not exist. These results suggest that cell disruption by the French press twice and sonication once is an effective method for improving purification efficiency. 相似文献
66.
Chang‐Mo Kang Jin Seong Hyeon So Ra Kim Eun Kyeong Lee Hyun Jin Yun Sun Young Kim Young Kee Chae 《化学与生物多样性》2015,12(11):1696-1705
We employed the primary cell model system as a first step toward establishing a method to assess the influence of ionizing radiation by using a combination of common and abundant metabolites. We applied X‐ray irradiation amounts of 0, 1, and 5 Gy to the cells that were harvested 24, 48, or 72 h later, and profiled metabolites by 2D‐NMR spectroscopy to sort out candidate molecules that could be used to distinguish the samples under different irradiation conditions. We traced metabolites stemming from the input 13C‐glucose, identified twelve of them from the cell extracts, and applied statistical analysis to find out that all the metabolites, including glycine, alanine, and gluatamic acid, increased upon irradiation. The combinatorial use of the selected metabolites showed promising results where the product of signal intensities of alanine and lactate could differentiate samples according to the dose of X‐ray irradiation. We hope that this work can form a base for treating radiation‐poisoned patients in the future. 相似文献
67.
Seong Yong Park Won Jun Kang Arthur Cho Ju Ri Chae Ye Lim Cho Jung Young Kim Ji Woong Lee Kyung Young Chung 《PloS one》2015,10(6)
Background
We designed a hypoxia-imaging modality to detect ischemia of the gastric conduit after esophagectomy.Materials and Methods
A rat esophagectomy model was created using 12-16-week-old, 300-350 g male Sprague-Dawley rats. In the operation group (n=6), partial gastric devascularization was performed by ligating the left gastric artery and the short gastric arteries and an esophagogastric anastomosis was performed. In the control group (n=6), the esophageal-gastric junction was incised and suturing was performed without gastric devascularization. Positron emission tomography (PET) images were taken using a microPET rodent model scanner, 24 h after the initial operation, after injection of 200 μCi 64Cu-diacetyl-bis (N4-methylsemicarbazone) (64Cu-ATSM) and pimonidazole 120 mg/kg. After microPET imaging, autoradiography and immunohistochemistry were performed.Results
The PET image revealed 64Cu-ATSM uptake at the fundus in the operation group 3 h after 64Cu-ATSM injection. The maximum percentage of the injected dose per gram of tissue was higher in the operation group (0.047±0.015 vs. 0.026±0.006, p=0.021). The fundus/liver ratio was also higher in the operation group (0.541±0.126 vs. 0.278±0.049, p=0.002). Upon autoradiography, 64Cu-ATSM uptake was observed in the fundus in the operation group, and was well-correlated to that observed on the PET image. Upon immunohistochemistry, expression of hypoxia-inducible factor 1a and pimonidazole were significantly increased at the fundus and lesser curvature compared to the greater curvature in the operation group.Conclusion
Hypoxia PET imaging with 64Cu-ATSM can detect ischemia in a rat esophagectomy model. Further clinical studies are needed to verify whether hypoxia imaging may be useful in humans. 相似文献68.
69.
Kwon D Shin K Kim S Ha Y Choi JH Yang JS Lee JY Chae C Oh HB Kang C 《Journal of microbiology (Seoul, Korea)》2010,48(5):657-662
This study aimed to characterize the replication and pathogenic properties of a Korean pandemic (H1N1) 2009 influenza virus
isolate in ferrets and mice. Ferrets infected with A/Korea/01/2009 (H1N1) virus showed mild clinical signs. The virus replicated
well in lungs and slightly in brains with no replication in any other organs. Severe bronchopneumonia and thickening of alveolar
walls were detected in the lungs. Viral antigens were detected in the bronchiolar epithelial cells, in peribronchial glands
with severe peribronchitis and in cells present in the alveoli. A/Korea/01/2009 (H1N1) virus-infected mice showed weight loss
and pathological lung lesions including perivascular cuffing, interstitial pneumonia and alveolitis. The virus replicated
highly in the lungs and slightly in the nasal tissues. Viral antigens were detected in bronchiolar epithelial cells, pneumocytes
and interstitial macrophages. However, seasonal H1N1 influenza virus did not replicate in the lungs of ferrets, and viral
antigens were not detected. Thus, this Korean pandemic (H1N1) 2009 isolate infected the lungs of ferrets and mice successfully
and caused more pathological lesions than did the seasonal influenza virus. 相似文献
70.
Yun-Seok Cho Jay Jooyoung Oh Kye-Heon Oh 《Biotechnology and Bioprocess Engineering》2010,15(2):359-364
The antimicrobial effects and biofilm formation inhibition of tea polyphenols (TPP) extracted from Korean green tea (Camellia sinensis L) were evaluated against 12 oral microorganisms. Effective antimicrobial activity against all microorganisms tested, including
Lactobacillus spp. (Lactobacillus acidophilus and Lactobacillus plantarum), Streptococcus spp. (Streptococcus mutans, Streptococcus sanguis, Streptococcus sobrinus, Streptococcus mitis, and Streptococcus salivarius), Staphylococcus aureus, Neisseria meningitidis, Escherichia coli, Enterobacter cloacae, Enterococcus faecalis, and Candida albicans, was shown at 2,000 μg/mL TPP within 5 min of incubation. Scanning electron microscopy (SEM) analysis revealed various morphological
changes, such as the presence of perforations, the formation of cell aggregates, and the leakage of cytoplasmic materials
from cells treated with TPP, depending on the bacteria. The potential role of TPP in biofilm formation inhibition on human
teeth was evaluated in BHI broth with 2 mixed strains of S. mutans and S. sanguis. SEM analysis showed biofilm formation on the surface of a tooth shaken only in saline solution, whereas almost no biofilm
was observed on a tooth incubated in TPP solution. This result suggests that TPP is effective against adherent cells of S. mutans and S. sanguis. Thus, TPP would be useful for development as an antimicrobial agent against oral microorganisms, and has great potential
for use in mouthwash solutions for the prevention and treatment of dental caries. 相似文献