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581.
The automatic titration of bilirubin 总被引:1,自引:0,他引:1
582.
Omar Falou Ali Sadeghi-Naini Sameera Prematilake Ervis Sofroni Naum Papanicolau Sara Iradji Zahra Jahedmotlagh Sharon Lemon-Wong Jean-Philippe Pignol Eileen Rakovitch Judit Zubovits Jacqueline Spayne Rebecca Dent Maureen Trudeau Jean Francois Boileau Frances C Wright Martin J Yaffe Gregory J Czarnota 《Translational oncology》2013,6(1):17-24
PURPOSE: Ultrasound elastography is a new imaging technique that can be used to assess tissue stiffness. The aim of this study was to investigate the potential of ultrasound elastography for monitoring treatment response of locally advanced breast cancer patients undergoing neoadjuvant therapy. METHODS: Fifteen women receiving neoadjuvant chemotherapy had the affected breast scanned before, 1, 4, and 8 weeks following therapy initiation, and then before surgery. Changes in elastographic parameters related to tissue biomechanical properties were then determined and compared to clinical and pathologic tumor response after mastectomy. RESULTS: Patients who responded to therapy demonstrated a significant decrease (P < .05) in strain ratios and strain differences 4 weeks after treatment initiation compared to non-responding patients. Mean strain ratio and mean strain difference for responders was 81 ± 3% and 1 ± 17% for static regions of interest (ROIs) and 81 ± 3% and 6 ± 18% for dynamic ROIs, respectively. In contrast, these parameters were 102±2%, 110±17%, 101±4%, and 109±30% for non-responding patients, respectively. Strain ratio using static ROIs was found to be the best predictor of treatment response, with 100% sensitivity and 100% specificity obtained 4 weeks after starting treatment. CONCLUSIONS: These results suggest that ultrasound elastography can be potentially used as an early predictor of tumor therapy response in breast cancer patients. 相似文献
583.
Jane McCusker Martin Cole Mark Yaffe Tamara Sussman Kim L Lavoie Erin Strumpf Maida Sewitch Deniz Sahin Manon de Raad 《Mental health in family medicine》2012,9(4):257-273
Objective We assessed the feasibility and acceptability to patients of a telephone-supported self-care intervention for depression among adults aged 40 years or over with one of six targeted chronic physical illnesses and comorbid depressive symptoms in family practice settings.Methods An open, uncontrolled trial (feasibility study) was conducted among patients treated in Montreal family practices. Eligible patients were aged 40 years or over, had one or more of the targeted chronic physical illnesses for at least 6 months (arthritis, hypertension, diabetes, heart disease, asthma and chronic obstructive pulmonary disease) and were evaluated as having at least mild depressive symptoms (a score of ≥ 5 on the 9-item Patient Health Questionnaire, PHQ-9). Participants received a package of six self-care tools (information booklet, video, Internet programme, action plan, workbook and mood-monitoring tool) with telephone support by a lay coach for up to 6 months.Results In total, 63 eligible patients provided written consent and completed the baseline interview; 57 (90%) and 55 (87%) patients completed 2-month and 6-month follow-up interviews, respectively. The mean number of telephone calls made by coaches to participants was 10.5 (SD 4.0), and the average length of these calls was 10.6 minutes. At the 6-month follow-up, 83.6% of the participants reported that one or more of the tools were helpful. Clinically significant improvements were seen in depressive symptoms (as assessed by the PHQ-9) at 6 months, with an effect size of 0.88 (95% CI, 0.55, 1.14).Conclusion A telephone-supported self-care intervention for depression was feasible, was acceptable to patients, and was associated with a significant 6-month improvement in depressive symptoms. A randomised trial of this intervention is justified. 相似文献
584.
Lee Goldstein Magal Yakey Yaffe Jeanne Shepshelovich Juan Francisco Aranda Maria del Carmen de Marco Katharina Gaus Miguel Angel Alonso Koret Hirschberg 《Molecular biology of the cell》2009,20(16):3751-3762
MAL, a compact hydrophobic, four-transmembrane-domain apical protein that copurifies with detergent-resistant membranes is obligatory for the machinery that sorts glycophosphatidylinositol (GPI)-anchored proteins and others to the apical membrane in epithelia. The mechanism of MAL function in lipid-raft–mediated apical sorting is unknown. We report that MAL clusters formed by two independent procedures—spontaneous clustering of MAL tagged with the tandem dimer DiHcRED (DiHcRED-MAL) in the plasma membrane of COS7 cells and antibody-mediated cross-linking of FLAG-tagged MAL—laterally concentrate markers of sphingolipid rafts and exclude a fluorescent analogue of phosphatidylethanolamine. Site-directed mutagenesis and bimolecular fluorescence complementation analysis demonstrate that MAL forms oligomers via ϕxxϕ intramembrane protein–protein binding motifs. Furthermore, results from membrane modulation by using exogenously added cholesterol or ceramides support the hypothesis that MAL-mediated association with raft lipids is driven at least in part by positive hydrophobic mismatch between the lengths of the transmembrane helices of MAL and membrane lipids. These data place MAL as a key component in the organization of membrane domains that could potentially serve as membrane sorting platforms. 相似文献
585.
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587.
Site-directed mutagenesis of alpha-tubulin. Reductive methylation studies of the Lys 394 region. 下载免费PDF全文
Previous studies have implicated at least two regions in alpha-tubulin that are important for the regulation of microtubule assembly. These regions include a cluster of basic residues consisting of Arg 390, His 393, and Lys 394 and the highly acidic carboxyl terminus. Lys 394 is highly reactive to HCHO and NaCNBH3. The reductive methylation of Lys 394 by these reagents is thought to be responsible for the profound inhibitory effects of low concentrations of HCHO on microtubule assembly (cf. Szasz J., M. B. Yaffe, M. Elzinga, G. S. Blank, and H. Sternlicht. 1986. Biochemistry. 25:4572-4582). In this study we reexamined the basis for this inhibition. Lys 394 in a human keratinocyte alpha-tubulin (k alpha 1) was replaced by a glutamic acid residue using site-directed mutagenesis. The mutant K394E was synthesized in vitro using rabbit reticulocyte lysates, and its ability to coassemble with bovine brain microtubule protein (MTP) before and after reaction with HCHO and NaCNBH3 was compared with that of wild-type. No differences in the coassemblies of the unmethylated proteins were detected suggesting that Lys 394 is not essential for microtubule assembly. However, methylated K394E prepared at low HCHO concentrations (< 1 mM) incorporated into microtubules to a greater extent (approximately 30-40%) than methylated wild-type. This result is consistent with the hypothesis that methylation of Lys 394 interferes with microtubule assembly. However, the extent of protection afforded by the replacement of Lys 394 with Glu 394 was less than half as large as that predicted from the earlier studies. We tentatively conclude that another residue(s) besides Lys 394 contributes significantly to the assembly-inhibition observed with low concentrations of HCHO. Since this residue(s) is less reactive than Lys 394, it would have to inhibit assembly substoichiometrically when methylated. Potential candidates for this residue include bulk lysyl residue(s), a lysyl residue(s) with intermediate reactivity toward HCHO, and the NH2-termini. The NH2-termini are especially attractive candidates since they appear to have a structural role in microtubule assembly. 相似文献
588.
The conversion of 2-ketoglutarate-[14C] to 5-aminolevulinic acid-[14C] (ALA) by a cell-free system from maize leaves is described. Optimal conversion was achieved at pH 6.2 using a 20 000 g supernatant after gel filtration through Sephadex G-25. The formation of ALA required Mg2+, an amino donor (alanine or glutamate), pyridoxal phosphate and NADH. NADPH was somewhat less effective. 相似文献
589.
Sarah W. Zangen Pirhiya Yaffe Svetlana Shechtman David H. Zangen Asher Ornoy 《Experimental diabetes research》2002,3(4):247-255
The role of the antioxidant defense mechanism in diabetesinduced
anomalies was studied in the Cohen diabetes-sensitive
(CDs) and -resistant (CDr) rats, a genetic model of nutritionally
induced type 2 diabetes mellitus. Embryos, 12.5-day-old, of CDs
and CDr rats fed regular diet (RD) or a diabetogenic high-sucrose
diet (HSD) were monitored for growth retardation and congenital
anomalies. Activity of superoxide dismutase (SOD) and catalaselike
enzymes and levels of ascorbic acid (AA), uric acid (UA), and
dehydroascorbic acid (DHAA) were measured in embryonic homogenates.
When fed RD, CDs rats had a decreased rate of pregnancy,
and an increased embryonic resorption. CDs embryos were
smaller than CDr embryos; 46% were maldeveloped and 7% exhibited
neural tube defects (NTDs). When fed HSD, rate of pregnancy
was reduced, resorption rate was greatly increased (56%;
P < .001), 47.6% of the embryos were retrieved without heart
beats, and 27% exhibited NTD. In contrast, all the CDr embryos
were normal when fed RD or HSD. Activity of SOD and catalase
was not different in embryos of CDs and CDr rats fedRD. When fed
HSD, levels of AA were significantly reduced, the ratio DHAA/AA
was significantly increased, and SOD activity was not sufficiently
increased when compared to embryos of CDr. The reduced fertility
of the CDs rats, the growth retardation, and NTD seem to be
genetically determined. Maternal hyperglycemia seems to result in environmentally induced embryonic oxidative stress, resulting in
further embryonic damage. 相似文献
590.