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61.
Mansoureh Togha Mehrdad Jahanshahi Leila Alizadeh Soodeh Razeghi Jahromi Gelareh Vakilzadeh Bahram Alipour Ali Gorji Amir Ghaemi 《Molecular neurobiology》2017,54(4):2445-2457
The immunomodulatory and anti-inflammatory properties of bone marrow-derived mesenchymal stem cells (BM-MSCs) have been considered as an appropriate candidate for treatment of autoimmune diseases. Previous studies have revealed that treatment with BM-MSCs may modulate immune responses and alleviate the symptoms in experimental autoimmune encephalomyelitis (EAE) mice, an animal model of multiple sclerosis. Therefore, the present study was designed to examine immunomodulatory effects of BM-MSCs in the treatment of myelin oligodendrocyte glycoprotein (MOG) 35-55-induced EAE in C57BL/6 mice. MSCs were obtained from the bone marrow of C57BL mice, cultured with DMEM/F12, and characterized with flow cytometry for the presence of cell surface markers for BM-MSCs. Following three passages, BM-MSCs were injected intraperitoneally into EAE mice alone or in combination with rapamycin. Immunological and histopathological effects of BM-MSCs and addition of rapamycin to BM-MSCs were evaluated. The results demonstrated that adding rapamycin to BM-MSCs transplantation in EAE mice significantly reduced inflammation infiltration and demyelination, enhanced the immunomodulatory functions, and inhibited progress of neurological impairments compared to BM-MSC transplantation and control groups. The immunological effects of rapamycin and BM-MSC treatments were associated with the inhibition of the Ag-specific lymphocyte proliferation, CD8+ cytolytic activity, and the Th1-type cytokine (gamma-interferon (IFN-γ)) and the increase of Th-2 cytokine (interleukin-4 (IL-4) and IL-10) production. Addition of rapamycin to BM-MSCs was able to ameliorate neurological deficits and provide neuroprotective effects in EAE. This suggests the potential of rapamycin and BM-MSC combined therapy to play neuroprotective roles in the treatment of neuroinflammatory disorders. 相似文献
62.
Hayat Mahmud Z Kassu A Mohammad A Yamato M Bhuiyan NA Balakrish Nair G Ota F 《Microbiological research》2006,161(1):25-37
Studies were conducted on the ecology of potentially pathogenic Vibrio parahaemolyticus in three coastal areas of Kii Channel, Tokushima, Japan. Seawater and seaweed samples were collected seasonally between June 2003 and May 2004. Total and toxigenic strains of V. parahaemolyticus were isolated using most probable number culture and colony blot hybridization. Toxigenic strains were serotyped and further characterized by random amplified polymorphic DNA (RAPD) and ribotyping. Six thousand strains of V. parahaemolyticus were isolated and 18 were found positive for tdh. V. parahaemolyticus were detected in all samples during summer and autumn, and from some samples during winter and spring. Among the toxigenic strains seven serotypes, five ribotypes and RAPD patterns were observed. Seven strains belonged to O3:K6 clone with identical ribotypes and RAPD patterns to that of a pandemic reference strain. The presence of toxigenic V. parahaemolyticus with pandemic potential might indicate a human health risk due to consumption of marine food sources. 相似文献
63.
The purpose of this study was to determine the relationship between the three-equation diffusing capacity for carbon monoxide (DLcoSB-3EQ) and lung volume and to determine how this relationship was altered when maneuvers were immediately preceded by a deep breath. DLcoSB-3EQ maneuvers were performed in nine healthy subjects either immediately after a deep breath or after tidal breathing for 10 min. The maneuvers consisted of slow inhalation of test gas from functional residual capacity to 25, 50, 75, or 100% of the inspiratory capacity and, without breath holding, slow exhalation to residual volume. After either a deep breath or tidal breathing, we found that DLcoSB-3EQ decreased nonlinearly with decreasing lung volume. At all lung volumes, DLcoSB-3EQ was significantly greater when measured after a deep breath than after tidal breathing. This effect increased as lung volume decreased, so that the greatest difference between DLcoSB-3EQ after a deep breath and that after tidal breathing occurred at the lowest lung volume. We conclude that a deep breath or spontaneous sigh has a role in reestablishing the pathway for gas exchange during tidal breathing. 相似文献
64.
Negar Alizadeh Abdollah Salimi Rahman Hallaj Fardin Fathi Farzad Soleimani 《Journal of nanobiotechnology》2018,16(1):93
Background
Given the great benefits of artificial enzymes, a simple approach is proposed via assembling of Ni2+ with hemin for synthesis of Ni-hemin metal–organic-frameworks (Ni-hemin MOFs) mimic enzyme. The formation of the Ni-hemin MOFs was verified by scanning electron microscopy, Transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Energy-dispersive X-ray spectroscopy and UV–vis absorption spectroscopy. This novel nanocomposite exhibited surprising peroxidase like activity monitored by catalytic oxidation of a typical peroxidase substrate, 3,3,5,5′-tetramethylbenzidine, in the presence of H2O2. By using folic acid conjugated MOF nanocomposite as a recognition element, we develop a colorimetric assay for the direct detection of cancer cells.Results
The proposed sensor presented high sensitivity and selectivity for the detection of human breast cancer cells (MCF-7) and Human Caucasian gastric adenocarcinoma. By measuring UV–vis absorbance response, a wide detection range from 50 to 105 cells/mL with a detection limit as low as 10 cells/mLwas reached for MCF-7 cells. We further discuss therapeutics efficiency of Ni-hemin MOFs in the presence of H2O2 and ascorbic acid. Peroxidase-mimic Ni-hemin MOFs as reactive oxygen species which could damage MCF-7 cancer cells, however for normal cells (human embryonic kidney HEK 293 cells) killing effect was negligible.Conclusions
Based on these behaviors, the developed method offers a fast, easy and cheap assay for the interest in future diagnostic and treatment application.65.
Helicobacter pylori infection reduces the risk of Barrett's esophagus: A meta‐analysis and systematic review
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Bálint Erőss Nelli Farkas Áron Vincze Benedek Tinusz László Szapáry András Garami Márta Balaskó Patrícia Sarlós László Czopf Hussain Alizadeh Zoltán Rakonczay Jr Tamás Habon Péter Hegyi 《Helicobacter》2018,23(4)
Introduction
The prevalence of Helicobacter pylori infection (HPI) has been decreasing in developed countries, with an increasing prevalence of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) at the same time. The aim of our meta‐analysis was to quantify the risk of BE in the context of HPI.Methods
A systematic search was conducted in 3 databases for studies on BE with data on prevalence of HPI from inception until December 2016. Odds ratios for BE in HPI were calculated by the random effects model with subgroup analyses for geographical location, presence of dysplasia in BE, and length of the BE segment.Results
Seventy‐two studies were included in the meta‐analysis, including 84 717 BE cases and 390 749 controls. The overall analysis showed that HPI reduces the risk of BE; OR = 0.68 (95% CI: 0.58‐0.79, P < .001). Subgroup analyses revealed risk reduction in Asia OR = 0.53 (95% CI: 0.33‐0.84, P = .007), Australia OR = 0.56 (95% CI: 0.39‐0.80, P = .002), Europe OR = 0.77 (95% CI: 0.60‐0.98, P = .035), and North‐America OR = 0.59 (95% CI: 0.47‐0.74, P < .001). The risk was significantly reduced for dysplastic BE, OR = 0.37 (95% CI: 0.26‐0.51, P < .001) for non‐dysplastic BE, OR = 0.51 (95% CI: 0.35‐0.75, P = .001), and for long segment BE, OR = 0.25 (95% CI: 0.11‐0.59, P = .001) in case of HPI.Conclusions
This extensive meta‐analysis provides additional evidence that HPI is associated with reduced risk of BE. Subgroup analyses confirmed that this risk reduction is independent of geographical location. HPI is associated with significantly lower risk of dysplastic, non‐dysplastic, and long segment BE. 相似文献66.
Sedigheh Alizadeh Peter J. Nixon Alison Telfer James Barber 《Photosynthesis research》1995,43(2):165-171
A rapid procedure has been developed for the isolation of the photosystem two reaction centre complex (PS II RC) from a double mutant of Chlamydomonas reinhardtii, F54-14, which lacks the Photosystem one complex and the chloroplast ATPase. Thylakoid membranes are solubilised with 1.5% (w/v) Triton X-100 and the PS II RC purified by anion-exchange chromatography using TSK DEAE-650(S) (Merck). The complex has a pigment stoichiometry of approximately six chlorophyll a: two pheophytin a: one cytochrome b-559: one to two -carotene. It photoaccumulates reduced pheophytin and oxidised P680 in the presence of sodium dithionite and silicomolybdate, respectively. Immunoblotting experiments have confirmed the presence of the D1 and D2 polypeptides in this complex. The -subunit of cytochrome b-559 was identified by N-terminal sequencing. Comparison of the complex with the PS II RC from pea using SDS-polyacrylamide gel electrophoresis showed that their polypeptide compositions were similar. However, the -subunit of cytochrome b-559 from C. reinhardtii has a lower apparent molecular weight than the pea counterpart whereas the -subunit is larger.Abbreviations DM
n-dodecyl -d-maltoside
- RC
reaction centre
- SiMo
silicomolybdate, SiMo12O40
4–
- TAP
Tris-acetate-phosphate 相似文献
67.
Elham Alizadeh Pasdar Michael Smits Michael Stapelberg Martina Bajzikova Marina Stantic Jacob Goodwin Bing Yan Jan Stursa Jaromira Kovarova Karishma Sachaphibulkij Ayenachew Bezawork-Geleta Margaryta Sobol Anatoly Filimonenko Marco Tomasetti Renata Zobalova Pavel Hozak Lan-Feng Dong Jiri Neuzil 《PloS one》2016,11(5)
68.
William G. Pitt Mahsa Alizadeh Ghaleb A. Husseini Daniel S. McClellan Clara M. Buchanan Colin G. Bledsoe Richard A. Robison Rae Blanco Beverly L. Roeder Madison Melville Alex K. Hunter 《Biotechnology progress》2016,32(4):823-839
The high morbidity and mortality rate of bloodstream infections involving antibiotic‐resistant bacteria necessitate a rapid identification of the infectious organism and its resistance profile. Traditional methods based on culturing the blood typically require at least 24 h, and genetic amplification by PCR in the presence of blood components has been problematic. The rapid separation of bacteria from blood would facilitate their genetic identification by PCR or other methods so that the proper antibiotic regimen can quickly be selected for the septic patient. Microfluidic systems that separate bacteria from whole blood have been developed, but these are designed to process only microliter quantities of whole blood or only highly diluted blood. However, symptoms of clinical blood infections can be manifest with bacterial burdens perhaps as low as 10 CFU/mL, and thus milliliter quantities of blood must be processed to collect enough bacteria for reliable genetic analysis. This review considers the advantages and shortcomings of various methods to separate bacteria from blood, with emphasis on techniques that can be done in less than 10 min on milliliter‐quantities of whole blood. These techniques include filtration, screening, centrifugation, sedimentation, hydrodynamic focusing, chemical capture on surfaces or beads, field‐flow fractionation, and dielectrophoresis. Techniques with the most promise include screening, sedimentation, and magnetic bead capture, as they allow large quantities of blood to be processed quickly. Some microfluidic techniques can be scaled up. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:823–839, 2016 相似文献
69.
E M Taher A M Ali A H Saad S H Gaily A K Ahmed 《Zeitschrift für mikroskopisch-anatomische Forschung》1989,103(6):993-1003
The histology and carbohydrate histochemistry of the nasal mucosa with attention to glandular tissue had been studied in 7 heads of sheep. Tissues were taken from vestibular region, septum at level of the alar fold, rostral portion of nasal conchae, caudal portion of nasal conchae, middle portion of septum and ethmoidal conchae region. Stratified squamous nonkeratinized epithelium was observed covering the vestibular region. The propria-submucosa of the nasal vestibule was richly permeated with glands having affinity for PAS and non-alcianophilic. The post-vestibular portion of the nasal cavity was lined by transitional epithelium and caudal to it, stratified columnar nonciliated epithelium was noticed. The respiratory epithelium covered the caudal half of the nasal conchae and the major portion of the septum as well as the recesses of the ethmoidal conchae. The glands associated with the respiratory mucosa were thick, coiled and tubular, containing both nonalcianophilic PAS positive and alcianophilic PAS positive cells. The olfactory mucosa covered the ethmoidal conchae and showed predominant serous glands. The results were discussed with that given for other mammals and in regard to the respiratory functions of the nasal mucosa. 相似文献
70.
The intestinal mast cell response to Trichinella spiralis infection in mast cell-deficient w/wv mice
The intestinal mast cell response and lymphoblast activity, as measured by the incorporation of 3H-thymidine into mesenteric lymph node cells (MLN) of WBB6F1-w/wv(w/wv) mice, their normal congenic littermates (+/+) and C57BL/6J mice, were compared after infection with Trichinella spiralis. Marked and similar blast cell activity and an increase in number of cells were observed in the MLN of infected w/wv and C57BL/6J mice 7 and 15 days P.I. In contrast to C57BL/6J mice, primary T. spiralis intestinal infections were prolonged in w/wv mice and more muscle larvae were recovered from w/wv mice 29 days post-infection. In C57BL/6J mice mucosal mast cell (MMC) numbers increased on day 7 P.I. whereas in w/wv mice these cells did not increase significantly until day 15 post-infection, reaching a peak on day 22. In w/wv mice, the response to secondary infection as determined by an accelerated expulsion of adult worms did not occur until day 11 postchallenge whereas in +/+ and C57BL/6J mice worm expulsion was nearly complete at that time. In both primary and secondary infections, the MMC numbers in w/wv mice were significantly lower than in C57BL/6J or +/+ mice. The results suggest that prolongation of T. spiralis infection in w/wv mice is associated with delayed appearance of mast cells in the intestinal mucosa which may reflect slow generation of the intestinal inflammatory response. 相似文献