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121.
目的:分析注射用血栓通中三七从原料到成品全过程的元素迁移规律,以便更好地控制成品中元素杂质。方法:采用ICP-MS法全面分析三七药材、三七总皂苷(中间体)和注射用血栓通中21种元素的含量。结果:21种元素的标准曲线相关系数r均在0. 999以上,回收率在92. 71%~107. 07%之间,RSD均在5%以内。三七药材中铝、铁含量较高,铅、砷、汞、镉、铜符合中华人民共和国药典的相关规定,三七总皂苷(中间体)和注射用血栓通中多数元素均未检出或含量极低。结论:注射用血栓通的提取工艺可有效去除三七中大部分元素,重金属及有害元素也降到较低水平。 相似文献
122.
In this study, the photo-induced degradation of azithromycin (Azi), erythromycin (Ery) and tylosin (Tyl) was investigated. The three macrolides are regularly found in different kinds of water, and are thus considered a potential environmental risk. In search of efficient ways for elimination, the compounds were systematically irradiated with a polychromatic UVC light source emitting 185, 254 and discretely further up to 580 nm. Due to their specific structural features, the macrolides possess different optical absorption characteristics leading to photodegradation pathways with dissimilar kinetic properties. Hence, the photodegradation products and their kinetics were analyzed using high-performance liquid chromatography (HPLC) coupled to high-resolution time-of-flight mass spectrometry. Among the degradants, i.e. the products formed during UV irradiation, both sugar moieties and lactone macrocycles were observed. Applying a first order kinetic model, the half-life of Azi was determined as 1.0?3.7 min, that of Ery as 1.0?14.2 min depending on the reaction conditions. The two compounds possess much lower absorption cross-sections than Tyl, in particular at 254 nm. Their half-lives appeared at least three times higher than that of Tyl that has t1/2 of 0.2?1.0 min. Based on quantum efficiency considerations, it was assumed that the degradation of Ery and Azi was mainly due to hydroxyl radical formation, which originated from water irradiation below 200 nm, whereas Tyl experienced predominantly photo induced degradation. The photodegradants of Azi exhibited half-lives of over 200 min, whereas most of the photo-products of Ery and Tyl showed half-lives of less than 10 min. Photodegradation processes were investigated at pH 3, pH 7 and pH 9 and in the presence of hydrogen peroxide. Both the educts and the photo-products were degraded more rapidly under neutral and acid conditions. 相似文献
123.
L. X. Peng L. Zou J. B. Wang J. L. Zhao D. B. Xiang G. Zhao 《Indian journal of pharmaceutical sciences》2015,77(6):661-667
The rutin, quercetin concentrations, antioxidant activity, and aroma compounds in different commercial tartary buckwheat tea were analyzed in our study. Results revealed that the materials and the processing protocol affected the chemical composition and activity of tartary buckwheat tea. Rutin and quercetin concentrations, antioxidant activity were significantly different in various kinds of tartary buckwheat tea, where the whole bran tea and the whole plant tea had the lower rutin, but higher quercetin concentrations and higher antioxidant activity. The whole embryo tea had the converse results. There was strong correlation between quercetin concentration and antioxidant activity (r>0.98, P<0.05). Meanwhile, Twenty eight different aroma compounds in tartary buckwheat tea were identified by gas chromatography-mass spectrometry. Those compounds were mainly composed of pyrazine, aldehydes, fatty acids and ketones. The main type of aroma compounds in different tartary buckwheat tea were similar, but their relative contents were different. The implications to the quality control of buckwheat tea were extensively discussed. 相似文献
124.
《Expert opinion on therapeutic patents》2013,23(10):1507-1510
Novel derivatives of 6-amino-2-benzylthio-4-hydroxypyrimidine are claimed as CXCR2 chemokine receptor antagonists useful in the treatment of chronic obstructive pulmonary disease, asthma and allergic rhinitis, inflammatory bowel disease, psoriasis, osteoarthritis, rheumatoid arthritis and cancer. The claimed compounds are monocylic analogues of previously described purine derivatives, at least some of which display reasonable affinity for the CXCR2 receptor. 相似文献
125.
126.
Heather K. Knych Rick M. Arthur Kirsten L. Kanarr Dan S. McKemie Philip H. Kass 《Drug testing and analysis》2019,11(9):1431-1443
Methamphetamine is a central and peripheral nervous system stimulant. There is only a single study that describes exposure to and disposition of this compound in horses. The potential for abuse and inadvertent exposure in equine athletes along with the limited data available necessitates further study. The objectives of the current study were to describe drug and metabolite concentrations, develop an analytical method that could be used to regulate its use, and describe selected pharmacodynamic effects. In phase 1, six horses were randomized into three transmucosal dose groups (n = 2/group; 0.5, 1.0 or 10 mg). In phase 2, horses received a single 10 mg intravenous dose. In phase 3, the effects of urinary pH on elimination were studied. Blood and urine samples were collected for up to 72 hours post drug administration. Concentrations of methamphetamine were measured using liquid chromatography–tandem mass spectrometry. Methamphetamine was below the limit of detection (LOD) in blood by 2, 4, and 18 hours following transmucosal administration of 0.5, 1, and 10 mg, respectively. Following intravenous administration, methamphetamine fell below the LOD between 12 and 18 hours. Following urinary acidification, methamphetamine fell below the limit of quantitation (LOQ) by 12 hours. In urine, methamphetamine was no longer detected at 48, 48, and 72 hours in the 0.5, 1, and 10 mg transmucosal groups and 18 hours in the intravenous group. Increased urinary pH resulted in urinary concentrations of methamphetamine falling below detectable levels by 48 hours post transmucosal administration. While the number of animals was small, behavioral, stimulatory, and cardiac effects were minimal. 相似文献
127.
128.
《Respiratory investigation》2020,58(3):131-133
Recent advances using molecular methods, matrix-assisted laser desorption ionization time of flightmass spectrometry, and next-generation sequencers enable rapid and precise detection of bacterial species in the clinical samples, revealing bacterial diversities in the human body. Corynebacterium species are Gram-positive bacilli, which can cause pneumonia and have been reported as causative pathogens of lower respiratory tract infections since the 1970's. However, Corynebacterium spp. may be recognized and sorted as part of normal respiratory flora on Gram staining and culture, resulting in clinical under-recognition as pathogenic bacteria.The results of the clone library method using bacterial 16S ribosomal RNA gene sequence analysis in Japanese patients with hospital-acquired pneumonia revealed that bronchoalveolar lavage fluid obtained from the lung lesions contained 11.8% Corynebacterium spp., which was the second most predominant bacterial phylotype. Additionally, among patients in whom Corynebacterium spp. were detected, C. simulans was most commonly detected followed by C. striatum. In addition, almost half of the patients in whom C. simulans was detected was monophylotypic infection and/or co-detection of C. simulansand C. striatum. Further clinical information is expected on corynebacteria as pathogens of lower respiratory tract infection. 相似文献
129.
130.
《Drug metabolism and pharmacokinetics》2019,34(5):340-349
The present study aims is to investigate the metabolic mechanism of Xue-Fu-Zhu-Yu decoction (XFZYD) in the treatment of blood-stasis syndrome in Coronary Heart Disease (CHD). To that end, 30 CHD patients with Blood-Stasis Syndrome (BSS) and 20 healthy subjects were enrolled. LC-Q-TOF/MS analysis determined that in comparison between CHD with BSS patients (Group A) and healthy subjects (Group C), 59 significantly differential metabolites in the positive mode and 18 significantly differential metabolites in the negative mode. The metabolite constituents in the plasma of 30 CHD with BSS patients before (group A) and after 30 days of treatment (Group B), and 20 healthy subjects (Group C) were analyzed using LC-Q-TOF/MS and GC-MS. Based on multivariate statistical analysis (PCA, PLS-DA and OPLS-DA), we determined 69 differential metabolites. The levels of hemorheology indexes were significantly down-regulated after treatment. Metabolic pathway attribution analysis showed that lipid metabolism, amino acid metabolism and bile acid metabolism pathways are involved. Our study identifies the metabolic networks of CHD and demonstrates the efficacy of this metabolomics approach to systematically study the therapeutic effect of XFZYC on CHD. 相似文献