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排序方式: 共有391条查询结果,搜索用时 31 毫秒
121.
Anton Valkov Faina Nakonechny Marina Nisnevitch 《International journal of molecular sciences》2014,15(9):14984-14996
The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in polystyrene, were found to exhibit high antibacterial activity in a continuous regime. The photosensitizers were immobilized by dissolution in chloroform, together with polystyrene, with further evaporation of the solvent, yielding thin polymeric films. Shallow reservoirs, bottom-covered with these films, were used for constructing continuous-flow photoreactors for the eradication of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and wastewater bacteria under illumination with visible white light using a luminescent lamp at a 1.8 mW·cm−2 fluence rate. The bacterial concentration decreased by two to five orders of magnitude in separate reactors with either immobilized RB or MB, as well as in three reactors connected in series, which contained one of the photosensitizers. Bacterial eradication reached more than five orders of magnitude in two reactors connected in series, where the first reactor contained immobilized RB and the second contained immobilized MB. 相似文献
122.
Kunshan Huang Beibei Huo Dongyao Li Prof. Jinping Xue Prof. Juanjuan Chen 《ChemMedChem》2020,15(9):794-798
Attractive results have been achieved with small-molecule target-based drugs in the anticancer field; however, enhancing their treatment effect and solving the problem of drug resistance remain key concerns worldwide. Inspired by the specific affinity of gefitinib for tumour cells and the strong oxidation capacity of singlet oxygen, we combined a chemically generated singlet oxygen moiety with the small-molecule targeted drug gefitinib to improve its anticancer effect. We designed and synthesised a novel compound ( Y5-1 ), in which a small-molecule targeted therapy agent (gefitinib) and a singlet oxygen (provided by an in vitro photodynamic reaction) thermally controlled releasing moiety are covalently conjugated. We demonstrated that the introduction of the singlet oxygen thermally controlled releasing moiety enhanced the anticancer activities of gefitinib. The results of this study are expected to provide a novel strategy to enhance the effect of chemotherapy drugs on drug-resistant cell lines. 相似文献
123.
124.
Knitted Silk Fibroin‐Reinforced Bead‐on‐String Electrospun Fibers for Sustained Drug Delivery Against Colon Cancer
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Bead‐on‐string electrospun fibers containing camptothecin (CPT) are fabricated on the surface of knitted silk fibroin (SF) meshes. Microscopic characterization reveals that the bead‐on‐string structure is prepared successfully and CPT is mainly located within the beaded structure. Interestingly, the CPT‐loaded beaded SF mesh (CPT‐SF mesh) has excellent mechanical properties. More importantly, it is able to perform a sustained CPT release without burst release. In vitro cytotoxicity tests further indicate that the CPT‐SF mesh shows much stronger anticolon cancer activity in comparison with SF meshes and beaded SF meshes. Hence, the CPT‐SF mesh has great potential as a promising local drug delivery system for colon cancer treatment. 相似文献
125.
Objective:The aim of this study was to evaluate the effect of the excision repair cross-complementing (ERCC1) expression on survival in advanced gastric cancer patients who underwent surgical resection and treated with oxaliplatin-based adjuvant chemotherapy. Methods: Sixty-three patients who underwent surgical resection for cure and treated with oxaliplatin-based adjuvant chemotherapy were included in this study. The expressions of ERCC1 of gastric cancer were examined by immunohistochemistry and the patients were categorized into ERCC1-(+) and ERCC1-(-) groups. The relation between ERCC1 expression and survival of patients was examined. Results: Of the 63 eligible patients, 36 patients (57.1%) had tumor with a positive expression of ERCC1 and the remaining 27 patients had tumor with a negative ERCC1 expression. Expression differences of ERCC1 didn't correlated with age (P - 0.827), gender (P = 0.12), differentiation (P = 0.113), historical type (P = 0.942), site of tumor (P = 0.221), size of tumor (P = 0.608), stage (P = 0.815) and lymphatic invasion (P = 0.165). Overall survival (OS) was significantly longer in patients without ERCC1 expression, when compared to patients with ERCC1 expression (P = 0.023). Multivariate analysis revealed that ERCC1 expression significantly impacted on OS (MR: 4.049; P = 0.000). Conclusion: We concluded that resected and treated with oxaliplatin-based adjuvant chemotherapy gastric cancer patients without ERCC1 expression have a better survival when compared to patients with ERCC1 expression. ERCC1 expression will hopefully provide a rational basis for improving adjuvant chemotherapeutic strategies for gastric cancer patients. ERCC1, itself, may be a prognostic factor for gastric cancer. 相似文献
126.
Jaber Emami Mahboubeh Rezazadeh Mahboubeh Rostami Farshid Hassanzadeh Hojjat Sadeghi Abolfazl Mostafavi 《Drug development and industrial pharmacy》2015,41(7):1137-1147
The aim of this study was to develop chitosan derivative polymeric micelles for co-delivery of paclitaxel (PTX) and α-tocopherol succinate (α-TS) to the cancer cells to improve the therapeutic efficiency and reduce side effects of PTX. In this study, amphiphilic tocopheryl succinate-grafted chitosan oligosaccharide was synthesized and physically loaded by PTX and α-TS with entrapment efficiency of 67.9% and 73.2%, respectively. Physical incorporation of α-TS into the micelles increased the hydrophobic interaction between PTX and the micelles core, which improved micelle stability, reduced the micelle size and also sustained the PTX release from the micelles. The mean particle size and zeta potential of αTS/PTX-loaded micelles were about 133?nm and +25.2?mV, respectively, and PTX release was completed during 6–9?d from the micelles. Furthermore, the cytotoxicity of α-TS/PTX-loaded micelles against human ovarian cancer cell line cancer cell in vitro was higher than that of PTX-loaded micelles and the free drug solution. Half maximal inhibitory concentration values of PTX after 48-h exposure of the cells to the PTX-loaded micelles modified and unmodified with α-TS were 110 and 188?ng/ml, respectively. 相似文献
127.
Dongdong Wang Zhen Guo Jiajia Zhou Jian Chen Gaozheng Zhao Ruhui Chen Mengni He Zhenbang Liu Haibao Wang Qianwang Chen 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(44):5956-5967
The versatile Mn3[Co(CN)6]2@SiO2@Ag core–shell NCs are prepared by a simple coprecipitation method. Ag nanoparticles with an average diameter of 12 nm deposited on the surface of Mn3[Co(CN)6]2@SiO2 through S–Ag bonding are fabricated in ethanol solution by reducing silver nitrate (AgNO3) with NaBH4. The NCs possess T1–T2 dual‐modal magnetic resonance imaging ability. The inner Prussian blue analogs (PBAs) Mn3[Co(CN)6]2 exhibit bright two‐photon fluorescence (TPF) imaging when excited at 730 nm. Moreover, the TPF imaging intensity displays 1.85‐fold enhancement after loading of Ag nanoparticles. Besides, the sample also has multicolor fluorescence imaging ability under 403, 488, and 543 nm single photon excitation. The as‐synthesized Mn3[Co(CN)6]2@SiO2@Ag NCs show a DOX loading capacity of 600 mg g−1 and exhibit an excellent ability of near‐infrared (NIR)‐responsive drug release and photothermal therapy (PTT) which is induced from the relative high absorbance in NIR region. The combined chemotherapy and PTT against cancer cells in vitro test shows high therapeutic efficiency. The multimodal treatment and imaging could lead to this material a potential multifunctional system for biomedical diagnosis and therapy. 相似文献
128.
Micelles: pH‐ and NIR Light‐Responsive Micelles with Hyperthermia‐Triggered Tumor Penetration and Cytoplasm Drug Release to Reverse Doxorubicin Resistance in Breast Cancer (Adv. Funct. Mater. 17/2015)
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129.
目的评价紫杉醇联合氟脲嘧啶/亚叶酸钙双周方案二线治疗晚期胃癌的疗效及毒性。方法分析一线化疗失败后采用紫杉醇联合氟脲嘧啶/亚叶酸钙双周方案作为二线化疗方案的48例晚期胃癌患者资料,评价缓解率(RR)、疾病进展时间(TTP)、总生存(OS)及不良反应。治疗方案为:紫杉醇100 mg.m-2,静脉滴注3 h;亚叶酸钙200 mg.m-2,静脉滴注2 h;随后给予氟脲嘧啶400 mg.m-2静脉推注,氟脲嘧啶2.4 g.m-2为微量泵持续泵注46 h。每2周给予1次化疗,每2次为1个疗程。结果 48例患者中,近期缓解率为22.9%,中位TTP及OS分别为3.6月和7.8月,获缓解患者中位OS明显长于未获缓解者(P〈0.05);患者耐受性良好,主要的不良反应为骨髓抑制、外周神经毒性、脱发、腹泻和肌肉关节疼痛。结论紫杉醇联合氟脲嘧啶/亚叶酸钙双周方案二线治疗PS评分高的晚期胃癌缓解率较高,不良反应可耐受,值得进一步开展前瞻性研究证实。 相似文献
130.
Weicai Chen Yuanyuan Yuan Du Cheng Jifeng Chen Lu Wang Xintao Shuai 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(13):2678-2687
Drug resistance is the greatest challenge in clinical cancer chemotherapy. Co‐delivery of chemotherapeutic drugs and siRNA to tumor cells is a vital means to silence drug resistant genes during the course of cancer chemotherapy for an improved chemotherapeutic effect. This study aims at effective co‐delivery of siRNA and anticancer drugs to tumor cells. A ternary block copolymer PEG‐PAsp(AED)‐PDPA consisting of pH‐sensitive poly(2‐(diisopropyl amino)ethyl methacrylate) (PDPA), reduction‐sensitive poly(N‐(2,2′‐dithiobis(ethylamine)) aspartamide) PAsp(AED), and poly(ethylene glycol) (PEG) is synthesized and assembled into a core‐shell structural micelle which encapsulated doxorubicin (DOX) in its pH‐sensitive core and the siRNA‐targeting anti‐apoptosis BCL‐2 gene (BCL‐2 siRNA) in a reduction‐sensitive interlayer. At the optimized size and zeta potential, the nanocarriers loaded with DOX and BCL‐2 siRNA may effectively accumulate in the tumor site via blood circulation. Moreover, the dual stimuli‐responsive design of micellar carriers allows microenviroment‐specific rapid release of both DOX and BCL‐2 siRNA inside acidic lysosomes with enriched reducing agent, glutathione (GSH, up to 10 mm ). Consequently, the expression of anti‐apoptotic BCL‐2 protein induced by DOX treatment is significantly down‐regulated, which results in synergistically enhanced apoptosis of human ovarian cancer SKOV‐3 cells and thus dramatically inhibited tumor growth. 相似文献