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1.
BackgroundThis study sought to determine trends in out-patient visits for gastrointestinal cancer (GC) at a quaternary hospital in KwaZulu-Natal (KZN), South Africa; and identify geographical regions which contribute most to GC-related out-patient clinic utilization at this hospital.MethodData for GC-related outpatient visits over an 11-year period was obtained from the hospital''s administrative database. Trends were analyzed using simple regression and trend line analyses. Patient residential postal codes from the administrative database were used to determine the geospatial distribution of complex GC in KZN.ResultsStrong increasing trends in GC-related out-patient visits were noted for age >65 years old (R2=0.8014), male (R2=0.7020), female (R2=0.7292), lower GC (R2=0.7094), and rural residence (R2=0.7008). Moderate increasing trends in GC-related out-patient visits were noted for age ≤65 years old (R2=0.6556), upper GC (R2=0.6498), and urban residence (R2=0.6988). The magnitude at which the number of out-patient visits increased was greater for urban residence when compared with rural residence (p=0.006). Urban centers and some regions along the North and South coast of KZN contributed the most toward GC-related out-patient visits.ConclusionOut-patient visits for complex GC in KZN are increasing. Several regions have been identified for anti-cancer interventions and decentralized out-patient services.  相似文献   
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用跳台法观察到党参总碱(DSA)能改善东莨菪碱(Scop)引起的记忆障碍,并能对抗Scop所致小鼠脑内乙酰胆碱(ACh)浓度下降及胆碱乙酰化酶(ChAT)活性的降低。体外实验发现当在反应液中加入DSA后,ChAT生成ACh的量增加。  相似文献   
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目的 研究四逆汤中乌头类生物碱的溶出平衡和水解平衡。方法 利用电喷雾质谱分析,比较了制附子、四逆汤、四逆汤药渣和含有3种双酯型生物碱的混合对照品体系中的乌头碱类二萜生物碱。结果 在煎煮过程中双酯型生物碱溶解并发生水解反应,而脂类生物碱则难溶于水。乌头碱、中乌头碱、次乌头碱水溶性相近,但是次乌头碱在水中的热稳定性更高,C19二萜骨架上C3取代基(—OH或—H)的变化影响生物碱的稳定性。结论四逆汤中的乌头碱类生物碱的种类及含量由其溶解性和化学稳定性共同决定。  相似文献   
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In order to identify genes which are expressed during alkaloid synthesis in an axenic culture of Claviceps sp. (strain ATCC 26245), a cDNA library from a producing culture was differentially screened with cDNA from producing (cDNA+) and non-producing (cDNA–) cultures, respectively. Altogether, ten cDNA clones were obtained, the alkaloid-synthesis-correlated expression of which was confirmed by Northern analyses. Evaluation of their nucleotide and derived amino-acid sequences identified one gene unequivocally, coding for dimethylallyltryptophan-synthase (DMAT-S), the initial enzyme of the specific alkaloid pathway. For two other genes significant homologies to known fungal genes were detected: one clone showed homology to the Neurospora crassa ccg1 gene, coding for a clock-regulated putative general stress protein; seven cDNA clones, derived from the same gene, which is highly expressed under these conditions, contained typical hydrophobin domains and long stretches of asparagine/glycine repeats (like QID3 from Trichoderma harzianum), thus probably representing a cell-wall constituent. These data show that this is not only a successful approach to clone genes specific for the alkaloid-pathway of C. purpurea, but also of genes which might be involved in the differentiation of sclerotial hyphae, the prerequisite for alkaloid synthesis. Received: 22 November 1996  相似文献   
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Vinpocetine, a derivate of vincamine, is widely used in the clinical pharmacotherapy of cerebral circulatory diseases. Herewith we report on a novel effect of vinpocetine: inhibition of retrograde axoplasmic transport of nerve growth factor (NGF) in the peripheral nerve. Blockade of retrograde transport of NGF results in transganglionic degenerative atrophy (TDA) in the segmentally related ipsilateral superficial spinal dorsal horn, which is characterized by depletion of the marker enzymes fluoride-resistant acid phosphatase (FRAP) and thiamine monophosphatase (TMP). At the same time, pain-related neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP), are depleted from lamina I-III from the segmentally related, ipsitateral Rolando substance of the spinal cord. On the basis of these experiments it is suggested that vinpocetine may result in a locally restricted decrease of nociception, that might be useful in clinical treatment of intractable pain. Pilot self-experiments support this assumption.  相似文献   
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Summary Hundred thirty-eight samples of heroin weighing more than 0.1g seized between 1981 and 1986 were characterized according to their contents of opium alkaloids, adulterants, and diluents together with their form and color. The chemical fingerprint was used to establish a change in the heroin during the period. As compared to the first few years covered by the survey, a predominant number of the samples at the end of the period were in the base form and contained the opium alkaloids papaverine and noscapine. In particular, the concentration of noscapine as related to the heroin content of each sample had increased considerably, indicating Pakistan or Iran as being the places of origin of most of the heroin seized in Denmark at the end of the period.  相似文献   
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The effect of lycoriside, an acylglucosyloxy alkaloid from Crinum asiaticum Linn, (family Amaryllidaceae), with or without sitosterol-3-O--D-glucoside, was studied on the rate of degranulation of peritoneal mast cells of albino rats. Lycoriside, at lower concentrations (1–20 µg/ml), in vitro, produced statistically significant protection against Tween 80-induced degranulation, as also to sensitized mast cells challenged with an antigen (horse serum). It also provided protection against compound 48/80-induced degranulation of mast cells when administered in vivo (1–5 mg/kg, po). At higher concentrations (100 µg/ml and above), in vitro, however, it had a mast-cell degranulation effect per se. The addition of sitosterol-3-O--D-glucoside to lycoriside did not modify the effect of the latter compound. The mechanism of the dual response elicited by lycoriside is appraised in view of a concentration-dependent anti- or prerelease effect on mast-cell mediators.  相似文献   
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A rapid assay is described for the simultaneous determination of emetine and cephaeline in ipecacuanha and its preparations, based upon the different fluorescence intensities of the alkaloids at pH 1 and pH 12. The assay involves the measurement of fluorescence at 317 nm of dilutions of the sample in 0.1 M hydrochloric acid (pH 1) and 0.01 M sodium hydroxide (pH 12) with an excitation wavelength of 283 nm. Concentrations of the individual alkaloids are calculated using two simultaneous equations derived from the experimentally determined coefficients of fluorescence of solutions (1 μg/ml) of emetine and cephaeline at pH 1 and pH 12. The procedure, which has been shown to be accurate, precise and sensitive, requires only 1 ml of a liquid sample and less than 0.5 g of powdered root. There was reasonable agreement between the total concentrations of alkaloids in tinctures and liquid extracts of ipecacuanha determined by the spectrofluorimetric method and by the titrimetric procedure of the British Pharmacopoeia. The fluorimetric procedure gave higher levels of alkaloids in the powdered root than did the B.P. method; this difference is explained by incomplete extraction of the alkaloids in the B.P. procedure for powdered ipecacuanha root.  相似文献   
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