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321.
Human plasminogen kringle 4. Crystallization and preliminary diffraction data of two different crystal forms 总被引:1,自引:0,他引:1
A M Mulichak C H Park A Tulinsky A M Petros M Llinás 《The Journal of biological chemistry》1989,264(4):1922-1923
Human plasminogen kringle 4 has been crystallized in two different crystal forms: monoclinic, a = 32.78(3), b = 49.17(2), c = 46.27(3) A, beta = 100.67 degrees, space group P2(1), four molecules/unit cell, two molecules/asymmetric unit; orthorhombic, a = 32.09(7), b = 49.14(6), c = 49.47(9) A, space group P2(1)2(1)2, four molecules/unit cell. Both crystal forms have a large protein fraction (66% for monoclinic and 62% for orthorhombic) and diffract x-rays to 2.0 A resolution. A self-rotation function has been calculated with monoclinic data indicating a non-crystallographic 2-fold rotation approximately parallel to a* (peak height of 14.3 x sigma). Cross-rotation function calculations are in progress utilizing the coordinates of the conserved structure of kringle 1 of prothrombin and plasminogen kringle 4. 相似文献
322.
George P. Karamanolis Stylianos Panopoulos Konstantinos Denaxas Anastasios Karlaftis Alexandra Zorbala Dimitrios Kamberoglou Spiros D. Ladas Petros P. Sfikakis 《Arthritis research & therapy》2016,18(1)
BackgroundAcute administration of the oral 5-HT1A receptor agonist buspirone, which is commonly used as an anxiolytic drug, may improve compromised lower esophageal sphincter function. In an open-label trial we assessed the effects of buspirone on esophageal motor function and symptoms in patients with esophageal involvement associated with systemic sclerosis (SSc).MethodsThirty consecutive patients with SSc and symptomatic esophageal involvement, despite treatment with proton pump inhibitors, underwent high resolution manometry and chest computed tomography for assessment of motor function and esophageal dilatation, respectively. Regurgitation, heartburn, dysphagia, and chest pain severity was subjectively scored by visual analog scales. Manometric parameters (primary endpoint) and symptom severity (secondary endpoint) were re-examined after 4-week daily administration of 20 mg buspirone. Other medications remained unchanged.ResultsEight patients did not complete the trial because of buspirone-associated dizziness (n = 2), or nausea (n = 2), or reluctancy to undergo final manometry. In the remaining 22 patients lower esophageal sphincter (LES) resting pressure increased from 7.7 ± 3.9 to 12.2 ± 4.6 mmHg (p = 0.00002) after buspirone administration; other manometric parameters did not change. Statistical analysis revealed negative correlation between individual increases in resting LES pressure and supra-aortic esophageal diameter (r = -0.589, p = 0.017), suggesting a more beneficial effect in patients with less severely affected esophageal function. Heartburn and regurgitation scores decreased at 4 weeks compared to baseline (p = 0.001, and p = 0.022, respectively).ConclusionOur findings warrant more conclusive evaluation with a double-blind controlled study; however, buspirone could potentially be given under observation for objective improvement in all patients with SSc who report reflux symptoms despite undergoing standard treatment.
Trial registration
ClinicalTrials.gov Identifier: Registered: 21-02-2014. NCT02363478相似文献323.
Kalpita S. Shringarpure Petros Isaakidis Karuna D. Sagili R. K. Baxi Mrinalini Das Amrita Daftary 《PloS one》2016,11(3)
Background
One-fifth of the patients on multidrug-resistant tuberculosis treatment at the Drug-Resistant-TB (DR-TB) Site in Gujarat are lost-to-follow-up(LFU).Objective
To understand patients’ and providers'' perspectives on reasons for LFU and their suggestions to improve retention-in-care.Design
Qualitative study conducted between December 2013-March 2014, including in-depth interviews with LFU patients and DOT-providers, and a focus group discussion with DR-TB site supervisors. A thematic-network analysis approach was utilised.Results
Three sub-themes emerged: (i) Struggle with prolonged treatment; (ii) Strive against stigma and toward support; (iii) Divergent perceptions and practices. Daily injections, pill burden, DOT, migratory work, social problems, prior TB treatment, and adverse drugs effects were reported as major barriers to treatment adherence and retention-in-care by patients and providers. Some providers felt that despite their best efforts, LFU patients remain. Patient movements between private practitioners and traditional healers further influenced LFU.Conclusion
The study points to a need for repeated patient counselling and education, improved co-ordination between various tiers of providers engaged in DR-TB care, collaboration between the public, private and traditional practitioners, and promotion of social and economic support to help patients adhere to MDR-TB treatment and avoid LFU. 相似文献324.
Karagiannidis AK 《Theriogenology》1995,43(3):605-613
Ten mature lactating ewes of the Chios island breed 3.5 +/- 0.5 (Mean +/- SEM) yr of age and weighing 51.9 +/- 1.6 kg (Mean +/- SEM) were synchronized for estrus with intravaginal sponges impregnated with 60 mg 6a-methyl-17-acetoxyprogesterone (MPA). The sponges remained in place for 14 d and 500 IU im PMSG were injected at their withdrawal. Daily milk samples (3 d pretreatment, 14 d on treatment, and 5 d posttreatment) were collected and analyzed by a double antibody RIA procedure for MPA. The concentration of MPA (Mean +/- SEM) in the milk increased to 5.05 +/- 0.11 ng/ml within the first day of sponge insertion, then declined and remained at a constant level (3.08 +/- 0.26 ng/ml) while the sponge was in place, eventually dropping to the background level (0.65 +/- 0.05 ng/ml) 24 h following sponge withdrawal. The curve for the quantity of MPA excreted in the milk was identical to that of MPA concentrations, showing significant differences among experimental days and among ewes. Finally, there was a significant relationship between milk production and MPA excretion into the milk (r = +0.581( * *)). It is concluded that only a very small percentage (0.08 +/- 0.01) of MPA contained in each sponge is excreted into the milk from the moment of sponge insertion until 5 d after its removal. 相似文献
325.
Prenatal diagnosis and a donor splice site mutation in fibrillin in a family with Marfan syndrome 总被引:12,自引:2,他引:10
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326.
The 3D structure of two unlabeled FK506 analogs, (R)- and (S)-[18-OH]ascomycin, when bound to [U-13C,15N]FKBP were determined by isotope-filtered 2D NMR experiments. The structures for the R and S isomers that bind tightly to FKBP but lack immunosuppressive activity are compared to each other and to the conformation of the potent immunosuppressant, ascomycin, when bound to FKBP. The results are interpreted in terms of calcineurin binding to the FKBP/ascomycin complex. 相似文献
327.
A P Hansen A M Petros A P Mazar T M Pederson A Rueter S W Fesik 《Biochemistry》1992,31(51):12713-12718
A method to obtain uniformly isotopically labeled (15N and 15N/13C) protein from mammalian cells is described. The method involves preparation of isotopically labeled media consisting of amino acids isolated from bacterial and algal extracts supplemented with cysteine and enzymatically synthesized glutamine. The approach is demonstrated by producing 15N-labeled and 15N/13C-labeled urokinase from Sp2/0 cells and successfully growing Chinese hamster ovary (CHO) cells on the labeled media. Thus, using the procedures described, isotopically labeled proteins that have been expressed in mammalian cells can be prepared, allowing them to be studied by heteronuclear multidimensional NMR techniques. 相似文献
328.
329.
Łukasz Walas Monika Dering Petros Ganatsas Marcin Pietras Emilia Pers-Kamczyc Grzegorz Iszkuło 《Plant biosystems》2018,152(5):1048-1058
Aesculus hippocastanum is a well-known species, which is popular because of its ornamental value. However, data on the demographic structure and potential distribution of A. hippocastanum are limited. The invasion of Cameraria ohridella into Europe has harmed those trees growing in artificial sites, but the presence of this insect in natural stands has been little studied. Here we aimed to investigate the demographic structure infestation level of natural populations of horse-chestnut. Additionally, Maxent modelling was used to predict the potential range of A. hippocastanum, based on the localities available in the literature. Field data analysis indicated that natural populations of A. hippocastanum are mostly found nearby mountain streams. The populations showed a diverse height structure and large numbers of seedlings, which indicate high population dynamics. The level of infestation by C. ohridella varied greatly and correlated with altitude. Secondary infestation might explain this infestation variability in some natural populations. Other hypotheses, such as environmental resistance factors or different genetic variability, are also discussed. By spatial distribution modelling, we found that the precipitation of the coldest and warmest quarters, as well as altitude, are important factors influencing the potential distribution of A. hippocastanum. 相似文献
330.
Xing Y Chaudry Q Shen C Kong KY Zhau HE Chung LW Petros JA O'Regan RM Yezhelyev MV Simons JW Wang MD Nie S 《Nature protocols》2007,2(5):1152-1165
Bioconjugated quantum dots (QDs) provide a new class of biological labels for evaluating biomolecular signatures (biomarkers) on intact cells and tissue specimens. In particular, the use of multicolor QD probes in immunohistochemistry is considered one of the most important and clinically relevant applications. At present, however, clinical applications of QD-based immunohistochemistry have achieved only limited success. A major bottleneck is the lack of robust protocols to define the key parameters and steps. Here, we describe our recent experience, preliminary results and detailed protocols for QD-antibody conjugation, tissue specimen preparation, multicolor QD staining, image processing and biomarker quantification. The results demonstrate that bioconjugated QDs can be used for multiplexed profiling of molecular biomarkers, and ultimately for correlation with disease progression and response to therapy. In general, QD bioconjugation is completed within 1 day, and multiplexed molecular profiling takes 1-3 days depending on the number of biomarkers and QD probes used. 相似文献