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91.
92.
Dina S. El-Kafrawy Amira H. Abo-Gharam Magdy M. Abdel-Khalek Tarek S. Belal 《Sustainable Chemistry and Pharmacy》2022
According to green analytical chemistry (GAC) principles, multi-analyte methods are usually more preferred than methods determining one analyte at a time (principle 8) as they allow saving resources (time, reagents and money) (principle 9) and permit the reduction of generated waste (principle 7) as well as reduction of needed samples (principle 2). The present work herein, describes for the first time the development, validation and comparison of novel green versatile multi-analyte HPLC-DAD and HPTLC methods for the quantitative estimation of five drugs (diacerein, aceclofenac, diclofenac sodium, celecoxib and meloxicam) within a single run in a short analysis time. For HPLC-DAD, separation was performed through using Zorbax SB C18 (4.6 × 250 mm, 5 μm particle size) with the mobile phase composed of 0.05 M phosphate buffer pH 3.0 and acetonitrile (42:58, v/v) at a flow rate of 1 mL/min. The chromatograms were extracted at 258, 276 and 355 nm. In HPTLC procedure, precoated TLC silica gel aluminum plates 60 F254 were used with a mobile phase consisting of mixture of (chloroform: methanol: acetic acid, 92:8:0.25, v/v/v). The developed plates were scanned densitometrically at 258, 280 and 360 nm. Validation of the proposed methods was performed following the ICH guidelines for linearity, ranges, precision, accuracy, robustness, detection and quantification limits. Good linearities were confirmed by the high values of correlation coefficients (r > 0.9992). Appraisal of the greenness of the developed methods and comparison with different reported chromatographic methods was performed using the analytical Eco-scale (AES) approach and the novel Analytical GREEnness (AGREE) metric. 相似文献
93.
Uzzan B Dumont-Fischer D Lahlou N Bihan H Boissier MC Alvarez JC Perret GY Cohen R 《Fundamental & clinical pharmacology》2008,22(2):159-160
We report 6 additional observations of a drug/hormone assay interaction between serum testosterone and phenylbutazone intake. This interaction had been described previously only once. We discuss its potential mechanisms, based upon our experimental findings, and its clinical implications. 相似文献
94.
Cai X Zhou H Wong YF Xie Y Liu ZQ Jiang ZH Bian ZX Xu HX Liu L 《Journal of ethnopharmacology》2007,110(1):39-48
QFGJS is an herbal preparation, and its pronounced effectiveness in treating adjuvant-induced arthritis (AIA) has been previously demonstrated. We herein aimed to confirm its anti-arthritic effect on collagen-induced arthritis (CIA) in rats. CIA was established in female Wistar rats with intradermal injection of type II bovine collagen at the base of the tail of animals. CIA rats were treated daily with oral administration of different doses of QFGJS beginning on the day of the induction of arthritis (day 0, the prophylactic treatment) or on the day after the onset of arthritis (day 13, the therapeutic treatment) until day 30. The results showed that prophylactic treatment with QFGJS significantly suppressed the onset of arthritis, and therapeutic treatment with QFGJS markedly reduced paw swelling and ESR levels even in the established CIA. Radiologic and histopathologic changes in the arthritic joints were also significantly reduced in the QFGJS-treated versus vehicle-treated rats. Moreover, the serum levels of pro-inflammatory cytokines TNF-alpha, IL-1beta, and IL-6 were markedly lowered in the QFGJS-treated rats. Hence, our studies demonstrate the quality, safety, and effectiveness of QFGJS as an anti-arthritic agent, which makes QFGJS a strong candidate for further clinical trials on rheumatoid arthritis (RA) patients. 相似文献
95.
NSAIDs enhance proteasomic degradation of survivin, a mechanism of gastric epithelial cell injury and apoptosis 总被引:1,自引:0,他引:1
NSAIDs cause severe gastrointestinal injury, in part by suppressing survivin, an inhibitor of apoptosis protein, both in cultured gastric epithelial cells and in human and rat gastric mucosa. The mechanism(s) of survivin down-regulation by NSAIDs is unclear. In this study, we examined whether NSAID treatment decreases survivin mRNA expression and/or enhances degradation of survivin protein via ubiquitin proteasome system in rat gastric mucosal, RGM-1 cells, and whether survivin overexpression prevents indomethacin-induced cell injury and apoptosis. Effects of indomethacin on survivin mRNA expression, survivin protein half-life and ubiquitination were examined in RGM-1 cells. Proteasome inhibitors were utilized to prevent indomethacin-induced survivin protein degradation in RGM-1 cells. The effects of stable overexpression of survivin on indomethacin-induced RGM-1 cell injury and apoptosis were examined. Results showed: (1) Indomethacin treatment did not alter survivin mRNA expression, but significantly reduced survivin protein half-life from 1.5h to approximately 1h and increased survivin ubiquitination. (2) Inhibition of ubiquitin proteasome prolonged survivin protein half-life to over 2h and inhibited indomethacin-induced survivin degradation. (3) Overexpression of survivin significantly reduced indomethacin-induced cell injury and apoptosis. In conclusion, indomethacin treatment enhances degradation of survivin via the ubiquitin proteasome machinery in RGM-1 cells, and maintenance of survivin levels is important for prevention of gastric epithelial cell injury and apoptosis. 相似文献
96.
Lauren E. Barber Kimberly A. Bertrand Shanshan Sheehy Laura F. White Hemant K. Roy Lynn Rosenberg Julie R. Palmer Jessica L. Petrick 《International journal of cancer. Journal international du cancer》2023,153(12):1978-1987
Evidence suggests that aspirin use reduces the occurrence of colorectal neoplasia. Few studies have investigated the association among Black Americans, who are disproportionately burdened by the disease. We assessed aspirin use in relation to colorectal adenoma among Black women. The Black Women's Health Study is a prospective cohort of self-identified Black American women established in 1995. Participants reported regular aspirin use on baseline and follow-up questionnaires. Beginning in 1999, participants reported undergoing a colonoscopy or sigmoidoscopy, the only procedures through which colorectal adenomas can be diagnosed. Multivariable logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between aspirin use and colorectal adenoma among 34 397 women who reported at least 1 colonoscopy or sigmoidoscopy. From 1997 through 2018, 1913 women were diagnosed with an adenoma. Compared to nonaspirin users, regular users had 14% (OR = 0.86, 95% CI: 0.78-0.95) lower odds of adenoma. The odds of adenoma decreased with increasing duration of aspirin use (≥10 years: OR = 0.80, 95% CI: 0.66-0.96). Initiating aspirin at a younger age was associated with a reduced adenoma occurrence (age < 40 years at initiation: OR = 0.69, 95% CI: 0.55-0.86). Regular aspirin use was associated with a decreased odds of colorectal adenoma in our study of Black women. These findings support evidence demonstrating a chemopreventive impact of aspirin on colorectal neoplasia and suggest that aspirin may be a useful prevention strategy among US Black women. 相似文献
97.
K. Daham W.‐ L. Song J. A. Lawson M. Kupczyk A. Gülich S.‐E. Dahlén G. A. FitzGerald B. Dahlén 《Clinical and experimental allergy》2011,41(1):36-45
Background Prostaglandin (PG) D2 is a pro‐inflammatory and bronchoconstrictive mediator released from mast cells, and is currently evaluated as a new target for treatment of asthma and rhinitis. It is not known which cyclooxygenase (COX) isoenzyme catalyses its biosynthesis in subjects with asthma. Objectives Primarily, to assess whether treatment with the COX‐2 selective inhibitor celecoxib inhibited biosynthesis of PGD2, monitored as urinary excretion of its major tetranor metabolite (PGDM). Secondarily, to determine the effects of the treatment on biosynthesis of PGE2, thromboxane A2 and PGI2, also measured as major urinary metabolites. Methods Eighteen subjects with asthma participated in a cross‐over study where celecoxib 200 mg or placebo were given b.i.d. on 3 consecutive days following 2 untreated baseline days. Six healthy controls received active treatment with the same protocol. Urinary excretion of the eicosanoid metabolites was determined by liquid chromatography/tandem mass spectrometry (LC/MS/MS). Lung function was followed as FEV1 and airway inflammation as fraction of exhaled nitric oxide (FENO). Results Celecoxib treatment inhibited urinary excretion of PGEM by 50% or more in subjects with asthma and healthy controls, whereas there was no significant change in the excretion of PGDM. In comparison with the healthy controls, the subjects with asthma had higher baseline levels of urinary PGDM but not of PGEM. The 3‐day treatment did not cause significant changes in FEV1 or FENO. Conclusion and Clinical Relevance Biosynthesis of PGD2 was increased in subjects with asthma and its formation is catalysed predominantly by COX‐1. By contrast, COX‐2 contributes substantially to the biosynthesis of PGE2. The asymmetric impact of celecoxib on prostanoid formation raises the possibility of long‐term adverse consequences of COX‐2 inhibition on airway homeostasis by the decreased formation of bronchodilator PGs and maintained production of increased levels of bronchoconstrictor PGs in asthmatics. Cite this as: K. Daham, W.‐ L. Song, J. A. Lawson, M. Kupczyk, A. Gülich, S.‐E. Dahlén, G. A. FitzGerald and B. Dahlén, Clinical & Experimental Allergy, 2011 (41) 36–45. 相似文献
98.
IntroductionFractures are increasing worldwide and with an aging population, are frequent in the elderly. The healing of fractures progresses through various phases including the inflammatory stage. Aging is associated with slower healing and the use of non steroidal anti-inflammatory drugs (NSAIDs) may interrupt bone healing processes. We designed a study to compare the effect of diclofenac and celecoxib on fracture callus histomorphometry in a rat model of different age groups.MethodsUsing 5 and 15 month old rats, fractures were induced on the left tibia and the animals allocated to receive one of the drugs. Animals were sacrificed at day 21 and 42 and the fracture callus harvested for processing and histological evaluation. Tissue proportions and histological grades were determined and compared across the groups.ResultsAcross all groups, the histological grade increased with time and animals in the young diclofenac group had the highest grade at day 42 (p = 0.004). The proportion of bone increased in all groups and was highest in the young diclofenac group at day 21 and day 42 (p = 0.003). Post hoc analysis showed that the young celecoxib and old celecoxib groups had the least proportion of bone (p = 0.032 and p = 0.003). The proportion of cartilage reduced in all groups at both time points.ConclusionCelecoxib was associated with lower histological grade and lower proportion of bone in older animals. We urge for caution regarding the use of celecoxib in older people for the management of pain associated with fractures. Diclofenac may be a better option in this group. 相似文献
99.
《The International journal of neuroscience》2012,122(6):755-764
Recent investigations have shown that, similarly to opioids, tolerance develops to the analgesic effects of nonsteroidal anti-inflammatory drugs (NSAIDs). Nitric oxide has been shown to play an important role in opioid-induced analgesic tolerance; we, therefore, planned to determine if nitric oxide also plays role in the analgesic tolerance to dipyrone, a NSAID. Using the hot-plate test in mice, an analgesic tolerance developed to dipyrone with its 150 and 300 mg/kg intraperitoneal doses after 7 days; no tolerance was observed with its dose of 600 mg/kg. Neither 7-nitroindazole (50 mg/kg, i.p.), a neuronal NOS inhibitor, nor aminoguanidine (30 mg/kg, i.p.), an inducible NOS inhibitor, had any effect on dipyrone-induced analgesic tolerance with doses, which also had no analgesic effect when used alone. Our results show that nitric oxide does not play role in the analgesic tolerance to dipyrone; however, further experiments are required to delineate the mechanisms and to take preventive measures against this problem, which will possibly limit the use of NSAIDs. 相似文献
100.