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61.
Flow cytometry sorting of viable bacteria and yeasts according to beta-galactosidase activity. 总被引:5,自引:2,他引:3 下载免费PDF全文
We describe a novel method for quantitative measurement of beta-galactosidase (beta-gal) levels in bacteria and yeasts by using flow cytometry, a method which allows viable microbial cells to be sorted on the basis of the expressed activity and to be recultivated. The method is based on encapsulating single cells in agarose microbeads 20 to 30 microns in diameter and analyzing the beta-gal activity of the colonies that develop (containing several hundred cells) by using the fluorogenic substrate fluorescein-di-beta-D-galactopyranoside (FDG). Three strains of Escherichia coli, containing different levels of beta-gal, served as a model system. A high degree of correlation was found between the average fluorescence measured per bead and the level of the enzyme in extracts of the respective strain. Although the use of FDG necessitates cell permeabilization, conditions were found under which a small part of each colony remained viable, yet most of the enzyme was exposed to the substrate. This allowed sorting of microcolonies and plating with close to 100% efficiency. The potential of the technique was demonstrated by selecting beta-gal-positive cells from an artificial mixture of beta-gal-positive and beta-gal-negative E. coli strains. 相似文献
62.
El Achi Hanadi Awwad Johnny Abou Daya Sarah Halabi Sahar Damianos Sandra Mahfouz Rami 《Molecular biology reports》2018,45(5):911-916
Molecular Biology Reports - Recurrent pregnancy loss (RPL) is a problem affecting up to 5% of women of childbearing age due to many factors. Studies have shown that RPL and cardiovascular disease... 相似文献
63.
Sahar Khajeh Vahid Razban Tahereh Talaei-Khozani Masoud Soleimani Reza Asadi-Golshan Farzaneh Dehghani Amin Ramezani Zohreh Mostafavi-Pour 《Biologia》2018,73(7):715-726
High incidence of articular cartilage defects resulting from age-related degeneration or trauma injuries is a major problem worldwide. Limited self-regeneration ability of cartilage often leads to inappropriate biochemistry and structure of healed tissue. Considering Impairments of traditional treatments, cell-based therapies are promising. The rapid ex vivo expansion and chondrogenic differentiation capability make dental pulp stem cells (DPSCs) a favorable cell type for therapeutic application, however strategies in order to efficient cartilage tissue-like production are imperative. In the present study the potential role of hypoxia mimicking agent, cobalt chloride (CoCl2), on chondrogenic differentiation of human DPSCs was surveyed. Cell viability assay used to obtain the optimum dose and exposure time of CoCl2. DPSCs were differentiated in pellet culture system after CoCl2 pretreatment. Chondrogenic differentiation efficiency was evaluated by histological and immunohistological analyses. The results showed that CoCl2 led to increased pellet size, integrity and matrix deposition with organizations more resembled typical cartilage lacuna structure. Furthermore, CoCl2 could improve differentiation by elevated chondrogenic markers, glycosaminoglycans (GAGs) and collagen II expression. CoCl2 pretreatment mitigated hypertrophy, as well, which was reflected in decreased collagen X expression. Alkaline phosphatase (ALP) specific activity did not change significantly by CoCl2 preconditioning. Based on current study hypoxia mimicking agent, CoCl2, could be suggested to promote DPSCs chondrogenic differentiation. 相似文献
64.
Sahar Saki Hedayat Bagheri Ali Deljou Mehrshad Zeinalabedini 《Physiology and Molecular Biology of Plants》2016,22(1):97-105
Descurainia sophia is a valuable medicinal plant in family of Brassicaceae. To determine the range of diversity amongst D. sophia in Iran, 32 naturally distributed plants belonging to six natural populations of the Iranian plateau were investigated by inter-simple sequence repeat (ISSR) markers. The average percentage of polymorphism produced by 12 ISSR primers was 86 %. The PIC values for primers ranged from 0.22 to 0.40 and Rp values ranged between 6.5 and 19.9. The relative genetic diversity of the populations was not high (Gst =0.32). However, the value of gene flow revealed by the ISSR marker was high (Nm = 1.03). UPGMA clustering method based on Jaccard similarity coefficient grouped the genotypes into two major clusters. Graph results from Neighbor-Net Network generated after a 1000 bootstrap test using Jaccard coefficient, and STRUCTURE analysis confirmed the UPGMA clustering. The first three PCAs represented 57.31 % of the total variation. The high levels of genetic diversity were observed within populations, which is useful in breeding and conservation programs. ISSR is found to be an eligible marker to study genetic diversity of D. sophia. 相似文献
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66.
Jalal Zaringhalam Asef Hormozi Elaheh Tekieh Jafar Razavi Ramin Khanmohammad Sahar Golabi 《Journal of physiology and biochemistry》2014,70(2):497-507
Opioid receptors play an important role in modulation of hyperalgesia in inflamed tissues, but chronic morphine application induces such side effects as tolerance. There is near communications between cytokines and mu opioid receptor expression. This study was aimed to assess the role of serum IL-10 in morphine tolerance development during adjuvant-induced arthritis. Adjuvant arthritis (AA) was induced on day 0 by single injection of Complete Freund’s Adjuvant (CFA) into the rats’ hindpaw. Hyperalgesia, edema, and spinal mu opioid receptor (mOR) variations were assessed on 0, 7, 14, and 21 days of the study. For assessment of the morphine tolerance development, morphine effective dose (4 mg/kg) was administered from the 14th day after CFA injection and continued until the morphine post-dose paw withdrawal latency (PWL); it did not significantly differ from the baseline. For assessment of the effects of IL-10 on tolerance induction, a neutralizing dose (ND50) of anti-IL-10 was administered daily during different stages of the study. AA induction in the right hindpaw of rats resulted in unilateral inflammation and hyperalgesia within 21 days of the study. Anti-IL-10 antibody administration in the AA rats induced marked elevation of hyperalgesia compared to the AA control group. Our data also indicated that morphine effective anti-hyperalgesic dose significantly decreased in the AA rats compared to the control group, which this symptom was aligned with spinal mu opioid receptor (mOR) expression increase during AA. Moreover, there was a significant difference in morphine tolerance induction between the AA and control rats, and our results also demonstrated that IL-10 played an important role in tolerance-induction process. It can be concluded that morphine tolerance slowly progressed when administered morphine effective dose was reduced during AA chronic inflammation. On the other hand, it seems that increased level of serum IL-10 may affect morphine tolerance development during inflammation. 相似文献
67.
Balkhi Sahar Mashayekhi Farhad Salehzadeh Ali Saedi Hamid Saeedi 《Molecular biology reports》2020,47(12):9637-9644
Molecular Biology Reports - Matrix metallopeptidases (MMPs) 1 and 3 have been shown to contribute to the initiation, and progression of different cancers, including breast cancer (BC). In this... 相似文献
68.
Clark RM De Biase I Malykhina AP Al-Mahdawi S Pook M Bidichandani SI 《Human genetics》2007,120(5):633-640
Friedreich ataxia (FRDA) is caused by homozygosity for FXN alleles containing an expanded GAA triplet-repeat (GAA-TR) sequence. Patients have progressive neurodegeneration of the dorsal
root ganglia (DRG) and in later stages the cerebellum may be involved. The expanded GAA-TR sequence is unstable in somatic
cells in vivo, and although the mechanism of instability remains unknown, we hypothesized that age-dependent and tissue-specific
somatic instability may be a determinant of the progressive pathology involving DRG and cerebellum. We show that transgenic
mice containing the expanded GAA-TR sequence (190 or 82 triplets) in the context of the human FXN locus show tissue-specific and age-dependent somatic instability that is compatible with this hypothesis. Small pool PCR
analysis, which allows quantitative analysis of repeat instability by assaying individual transgenes in vivo, showed age-dependent
expansions specifically in the cerebellum and DRG. The (GAA)190 allele showed some instability by 2 months, progressed at about 0.3–0.4 triplets per week, resulting in a significant number
of expansions by 12 months. Repeat length was found to determine the age of onset of somatic instability, and the rate and
magnitude of mutation. Given the low level of cerebellar instability seen by others in multiple transgenic mice with expanded
CAG/CTG repeats, our data indicate that somatic instability of the GAA-TR sequence is likely mediated by unique tissue-specific
factors. This mouse model will serve as a useful tool to delineate the mechanism(s) of disease-specific somatic instability
in FRDA. 相似文献
69.
70.
Sahar Keshvari Berit Genz Ngari Teakle Melanie Caruso Michelle F. Cestari Omkar L. Patkar Brian W. C. Tse Kamil A. Sokolowski Hilmar Ebersbach Julia Jascur Kelli P. A. MacDonald Gregory Miller Grant A. Ramm Allison R. Pettit Andrew D. Clouston Elizabeth E. Powell David A. Hume Katharine M. Irvine 《Disease models & mechanisms》2022,15(4)