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排序方式: 共有4379条查询结果,搜索用时 15 毫秒
1.
Simultaneous Determination of Six Compounds in Rat Plasma by Ultra‑Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan‑Shu Yu‑Fang 下载免费PDF全文
Hai Jiang A‑Jiao Hou Yan‑Yan Zhang Wen‑Jing Man Liu Yang Yong‑Hai Meng Xin‑Yue Guo Song Wang Jia‑Xu Zhang Bing‑You Yang Qiu‑Hong Wang Kelvin Chan Hai‑Xue Kuang 《World Journal of Traditional Chinese Medicine》2019,(4)
A rapid and high selective ultra?performance liquid chromatography (UPLC) with tandem mass spectrometry method for simultaneous
determination of six compounds including albiflorin, paeoniflorin, picroside I, picroside II, saikosaponin A, and saikosaponin D in rat plasma
was developed and validated using butyl p-hydroxybenzoate as an internal standard. One-step direct protein precipitation with acetonitrile was
used to extract the compounds from the rat plasma samples. Chromatographic separation was achieved using an ACQUITY UPLC BEH C18
column (100 mm × 2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile
were used as the Mobile phase A and B. Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify
and quantify active components. Calibration curves showed good linearity (R2 > 0.9908) over a wide concentration range for all compounds.
The intra- and interday precision (relative standard deviation) ranged 2.4%–7.0% and 2.6%–8.0%, respectively. The accuracy (relative error)
was from ?13.0% to 13.2% at all quality control levels. The recovery ranged from 81.1% to 92.5%. The validated method was successfully
applied to pharmacokinetic study in rats after oral administration of Qing Gan?Shu Yu?Fang. The results show that one can draw a conclusion
that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo. 相似文献
2.
Identification of differentially expressed genes in omental adipose tissues of obese patients by suppression subtractive hybridization 总被引:1,自引:0,他引:1
Qiu J. Ni Y. H. Gong H. X. Fei L. Pan X. Q. Guo M. Chen R. H. Guo X. R. 《南京医科大学学报(自然科学版)》2007,27(5):427-427
To identify differentially expressed genes between obese individuals and normal control, we have undertaken suppression subtractive hybridization (SSH). Omental adipose tissues were obtained via abdominal surgery for appendicitis in both 13 obese subjects[BMI (body mass index) 〉 30 kg/m(2)] and 13 normal subjects (BMI 〉 18 and 〈 25 kg/m(2)). 相似文献
3.
Jin-ming Gao* Yao-guang Lin Chang-chun Qiu Yi-wen Liu Yi Ma and Ying LiuDepartment of Respiratory Disease Peking Union Medical College Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing National Laboratory of Medical Molecular Biology Chinese Academy of Medical Sciences Peking Union Medical College Beijing 《中国医学科学杂志(英文版)》2004,19(3):164-169
THEβ2-adrenergicreceptor(β2-AR)ishighlyexpre-ssedonairwaysmoothmusclecellsinlung,anddefectsinβ2-ARsignalpathwaywereinvolvedinthepathogenesisofasthma.1 Humanβ2-ARgeneisanintr-onlessgenewithacodingblockconsistingof1239nucleo-tidesonchromosome5q31-32,genome-widesearchforas-thmasusceptibilitylocishowedthatmarkersonthisregionhavebeenlinkedtoasthma-associatedphenotypesinvariousethnicpopulations.2 Reihsausetal3 firstdescribedninecod-ingregionpolymorphisms,particularly,thethreecommonaminoacidsu… 相似文献
4.
5.
Qiu Ming-cai邱明才 Li Song-lingand Bai Cheng-jiang白成江李松岭 Zhang Nai-xin张乃鑫Department of Endocrinology the First AffiliatedHospital Tianjin Medical College Tianjin 《中华医学杂志(英文版)》1987,100(4):330-332
Histomorphometric study was made on a series
of sections of undecalcified epiphyseal femoral
specimens from rats with experimental fluorosis. The
results revealed osteosclerosis in Group A (5 ppm)
being more severe than that in Group B (25 ppm)
With the increase of fluoride dose, the parameters
fell down instead of increased in parallel. There is
seemingly a threshold over which osteosclerosis in
fluorosis becomes less severe. In contrast to Bely's
conclusion the authors proposed that, fluoride toxi-
city, besides decreasing the number of osteoblasts,
may also activate the osteoblasts. The number of
osteoblasts may be increased with relative lower
dose of fluoride also. The net outcome is the in
crement in bone volume. When toxic dose of
fluoride is higher enough (higher than the proposed
threshold), however, the number of osteoblasts and
its activity are inhibited. So are the osteocytes. This
interpretation may be the cytological basis for
osteosclerosis in the experimental fluorosis. 相似文献
6.
瘦素、骨保护素与骨代谢 总被引:5,自引:0,他引:5
骨组织时刻处于骨重建的动态变化之中,即不间断的骨形成、骨吸收贯穿生命的始终。骨重建的范围非常广泛,几乎每10年成人骨骼完全再生一次。对于健康青年人,骨形成量与骨吸收量保持动态平衡。随着年龄增长,骨吸收日益占据优势,由此可导致骨质疏松等衰老性疾病的发生。骨重建的过程有赖于两大类细胞的活性:其一是成骨细胞,负责生成新骨(骨形成);其二是破骨细胞,负责破坏旧骨(骨吸收)。骨代谢研究中的主要问题就是研究成骨细胞和破骨细胞分化和活性的调控机制,以期实现骨重建的动态平衡,达到预防和治疗各种代谢性骨病的目的。… 相似文献
7.
8.
邱明才 《中华内分泌代谢杂志》2007,23(3):193-194
原发性骨质疏松的诊断首先要除外继发性骨质疏松。后者包括的范围很广,内容也很多,需要广博的内科学基础和辨证的逻辑思维才能予以正确鉴别。骨密度检查只能作为一种参考,而不能作为诊断原发性骨质疏松的唯一依据。 相似文献
9.
细胞凋亡信息分子Fas、FasL和NF-κB在氟化物作用后破骨样细胞凋亡过程中的表达 总被引:2,自引:0,他引:2
目的研究氟化物作用后破骨细胞样细胞凋亡过程中细胞凋亡配体Fas、FasLFasLigand和核因子NF-κB的表达变化。方法在培养基中分别加入不同浓度的氟化钠培养破骨样细胞,以免疫组织化学染色方法观察细胞的Fas、FasL和NF-κB表达。结果Fas、FasL在破骨样细胞表达量随培养基中氟化钠浓度增高而增高;NF-κB的表达量随培养基中氟化钠浓度增高而降低,两者均具有剂量依赖关系。结论在氟化钠所致的破骨细胞凋亡过程中,Fas,Fas-L的表达随氟化物浓度增高而加强;而核因子NF-κB的表达随氟化物浓度增高而减弱,两者都具有剂量依赖关系。 相似文献
10.
Immune biology of macaque lymphocyte populations during mycobacterial infection 总被引:3,自引:0,他引:3 下载免费PDF全文
Lai X Shen Y Zhou D Sehgal P Shen L Simon M Qiu L Letvin NL Chen ZW 《Clinical and experimental immunology》2003,133(2):182-192
Immune responses of lymphocyte populations during early phases of mycobacterial infection and reinfection have not been well characterized in humans. A non-human primate model of Mycobacterium bovis bacille Calmette-Guerin (BCG) infection was employed to characterize optimally the immune responses of mycobacteria-specific T cells. Primary BCG infection induced biphasic immune responses, characterized by initial lymphocytopenia and subsequent expansion of CD4+, CD8+ and gammadelta T cell populations in the blood, lymph nodes and the pulmonary compartment. The potency of detectable T cell immune responses appears to be influenced by the timing and route of infection as well as challenge doses of BCG organisms. Systemic BCG infection introduced by intravenous challenge induced a dose-dependent expansion of circulating CD4+, CD8+ and gammadelta T cells whereas, in the pulmonary compartment, the systemic infection resulted in a predominant increase in numbers of gammadelta T cells. In contrast, pulmonary exposure to BCG through the bronchial route induced detectable expansions of CD4+, CD8+ and gammadelta T cell populations in only the lung but not in the blood. A rapid recall expansion of these T cell populations was seen in the macaques reinfected intravenously and bronchially with BCG. The expanded alphabeta and gammadelta T cell populations exhibited their antigen specificity for mycobacterial peptides and non-peptide phospholigands, respectively. Finally, the major expansion of T cells was associated with a resolution of active BCG infection and reinfection. The patterns and kinetics of CD4+, CD8+ and gammadelta T cell immune responses during BCG infection might contribute to characterizing immune protection against tuberculosis and testing new tuberculosis vaccines in primates. 相似文献