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61.
Nucleostemin (NS) is a nucleolar protein involved in stem cell (SC) self-renewal by controlling cell cycle progression. In addition to SCs, NS is also expressed in some highly proliferating cells including several adult stem cells and cancer cell lines. NS knock-down in different cell lines demonstrated its cell type-dependent function in arresting cell cycle in either G1 or G2/M phases. Here, we have evaluated the expression of NS and iPS genes in 36 gastric cancer and their matched marginal nontumor tissues by means of real-time polymerase chain reaction (RT-PCR). We have also examined a potential causative role of NS in gastric tumorigenesis by suppressing its expression in a gastric cancer cell line, AGS. Our data revealed that NS expression level is much higher in tumor tissues (p?=?0.046), especially in high-grade ones (p?<?0.001), whereas the expression of Klf4 and Sox2 is downregulated in tumor tissues compared to marginal nontumor samples (p?<?0.001). Furthermore, NS suppression in the AGS cell line caused some morphological alterations, a cell cycle arrest at G1 phase, and an upregulation of iPS genes: Nanog, Sox2, and Klf4. Based on our results, NS overexpression seems to have a causative role in gastric tumorigenesis and/or progression, and it could be considered as a potential tumor marker for diagnosis, molecular classification, and molecular therapy of gastric adenocarcinoma. 相似文献
62.
Mohammad Reza Mirzaei Ali Najafi Mohammad Kazemi Arababadi Malek Hosein Asadi Seyed Javad Mowla 《Tumour biology》2014,35(10):9999-10009
OCT4B1 is a newly discovered spliced variant of OCT4 which is primarily expressed in pluripotent and tumor cells. Based on our previous studies, OCT4B1 is significantly overexpressed in tumors, where it endows an anti-apoptotic property to tumor cells. However, the mechanism by which OCT4B1 regulates the apoptotic pathway is not yet elucidated. Here, we investigated the effects of OCT4B1 suppression on the expression alteration of 84 genes involved in apoptotic pathway. The AGS (gastric adenocarcinoma), 5637 (bladder tumor), and U-87MG (brain tumor) cell lines were transfected with OCT4B1 or irrelevant siRNAs. The expression level of apoptotic genes was then quantified using a human apoptosis panel-PCR kit. Our data revealed an almost similar pattern of alteration in the expression profile of apoptotic genes in all three studied cell lines, following OCT4B1 suppression. In general, the expression of more than 54 apoptotic genes (64 % of arrayed genes) showed significant changes. Among these, some up-regulated (CIDEA, CIDEB, TNFRSF1A, TNFRSF21, TNFRSF11B, TNFRSF10B, and CASP7) and down-regulated (BCL2, BCL2L11, TP73, TP53, BAD, TRAF3, TRAF2, BRAF, BNIP3L, BFAR, and BAX) genes had on average more than tenfold gene expression alteration in all three examined cell lines. With some minor exceptions, suppression of OCT4B1 caused upregulation of pro-apoptotic and down-regulation of anti-apoptotic genes in transfected tumor cells. Uncovering OCT4B1 down-stream targets could further elucidate its part in tumorigenesis, and could lead to finding a new approach to combat cancer, based on targeting OCT4B1. 相似文献
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Zhang B Weng Z Sismanopoulos N Asadi S Therianou A Alysandratos KD Angelidou A Shirihai O Theoharides TC 《International archives of allergy and immunology》2012,159(1):23-32
Background: Mast cells are immune cells derived from hematopoietic precursors that mature in the tissue microenvironment. Mast cells are critical for allergic, immune and inflammatory processes, many of which involve tumor necrosis factor (TNF). These cells uniquely store TNF in their secretory granules. Upon stimulation, mast cells rapidly (30 min) secrete β-hexosaminidase and granule-stored TNF through degranulation, but also increase TNF mRNA and release de novo synthesized TNF 24 h later. The regulation of these two distinct pathways is poorly understood. Methods: Human LAD2 leukemic mast cells are stimulated by substance P. TNF secretion and gene expression were measured by ELISA and real-time PCR, and mitochondrial dynamics was observed in live cells under confocal microscopy. Cell energy consumption was measured in terms of oxygen consumption rate. Results: Here, we show that granule-stored TNF is preformed, and its secretion from LAD2 mast cells stimulated by substance P (1) exhibits higher energy consumption and is inhibited by the mitochondrial ATP pump blocker oligomycin, (2) shows rapid increase in intracellular calcium levels, and (3) exhibits reversible mitochondrial translocation, from a perinuclear distribution to the cell surface, as compared to de novo synthesized TNF release induced by lipopolysaccharide. This mitochondrial translocation is confirmed using primary human umbilical cord blood-derived mast cells stimulated by an allergic trigger (IgE/streptavidin). Conclusion: Our findings indicate that unique mitochondrial functions distinguish granule-stored from newly synthesized TNF release from human mast cells, thus permitting the versatile involvement of mast cells in different biological processes. 相似文献
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Laryngeal adenosquamous carcinoma (ASC) is a rare malignancy, and the problems in true diagnosis of this entity are well known. In this paper, we describe a case of ASC and discuss its distinct histopathology in metastatic lymph nodes. A heavy smoker man presented with a progressive neck mass. Based on incisional biopsy, diagnosis of squamous cell carcinoma (SCC) was made and total laryngectomy with bilateral radical neck dissection was performed. Sections of primary tumor showed a well-differentiated SCC. However, lymph node metastases had a distinct feature of glandular structures. Further investigation with Mayer's mucicarmine stain confirmed the presence of rare scattered glands in primary tumor and the final diagnosis was changed to ASC. Adenosquamous carcinoma is a distinct entity and must be distinguished from the common SCC of larynx. As a result, when a lesion with diagnosis of squamous cell carcinoma shows evidence of glandular differentiation in a subsequent biopsy or in nodal metastases, more investigation is necessary. Moreover, the glandular structures in primary tumor, as in this case, may be rare and inconspicuous. Therefore, we suggest the precise evaluation of metastatic lymph nodes for any laryngeal tumor with diagnosis of SCC. This helps to make appropriate therapeutic decisions with respect to the aggressive behavior of ASC and its high propensity for lymph node metastasis. 相似文献
67.
Maryam Hakimi Parizi Iraj Sharifi Saeedeh Farajzadeh Abbas Pardakhty Mohammad Hossein Daie Parizi Hamid Sharifi Ali Reza Keyhani Mahshid Mostafavi Mehdi Bamorovat Ahmad Khosravi Daryoush Ghaffari 《Asian Pacific journal of tropical medicine》2019,(8)
Objective: To explore the antileishmanial effect of tioxolone and its niosomal form against Leishmania tropica. Methods: Tioxolone niosomes were prepared by the hydration method and were evaluated for morphology, size, release study, and encapsulation efficiency. The cytotoxicity of tioxolone and its niosomal form was measured by MTT assay, leishmanicidal activity against promastigote and amastigote by MTT assay, apoptosis by flow cytometry, IL-12, IL-10 and metacaspase gene expression levels by q-PCR. Results: Span/Tween 40 and Span/Tween 60 niosomes had good physical stability as depicted in their size distribution curves and high encapsulation efficiency(99%). The release profile of the entrapped compounds showed Fickian's model of tioxolone delivery based on diffusion through lipid bilayers. With the IC50 value for amastigote as(24.5±2.1) μg/mL and selectivity index as 10.5, the Span/Tween 60 niosome(NT2) had a superior effect to other drugs. The CC50 value and IC50 of promastigote value for NT2 were(257.5±24.5) μg/mL and(164.8±20.6) μg/mL, respectively. The flow cytometric analysis showed that tioxolone and niosomal forms induced apoptosis of Leishmania tropica promastigotes in a dose-dependent manner. NT2 increased the expression level of IL-12 and metacaspase genes and decreased the expression level of the IL-10 gene.Conclusions: Niosomes of tioxolone play an immunomodulatory role in increasing Th1 cytokine profile and inhibiting the Th2 cytokine profile. It could be used for treatment of anthroponotic cutaneous leishmaniasis. 相似文献
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69.
Ablative fractional lasers were introduced for treating facial rhytides. Few studies have compared fractional CO2 and Er:YAG lasers on cutaneous photodamages by a split trial. The aim of the present study was to compare these modalities in a randomized controlled double-blind split-face design with multiple sessions and larger sample size compared to previous studies done before. Forty patients with facial wrinkles were enrolled. Patients were randomly assigned to receive three monthly treatments on each side of the face, one with a fractional CO2 and one with a fractional Er:YAG laser. The evaluations included investigating clinical outcome determined by two independent dermatologists not enrolled in the treatment along with measuring skin biomechanical property of cheeks using a sensitive biometrologic device with the assessment of cutaneous resonance running time (CRRT). Moreover, possible side effects and patients’ satisfaction have been recorded at baseline, 1 month after each treatment, and 3 months after the last treatment session. Clinical assessment showed both modalities significantly reduce facial wrinkles (p value?<?0.05), with no appreciable difference between two lasers. Mean CRRT values also decreased significantly after the laser treatment compared to the baseline in both laser groups. There was no serious long-standing adverse effect after both laser treatments, but the discomfort was more pronounced by the participants after CO2 laser treatment. According to the present study, both fractional CO2 and fractional Er:YAG lasers show considerable clinical improvement of facial skin wrinkles with no serious adverse effects, but post-treatment discomfort seems to be lower with Er:YAG laser. 相似文献
70.