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21.
Prediction of phenotype for acetylation and for debrisoquine hydroxylation by DNA-tests in healthy human volunteers 总被引:5,自引:0,他引:5
T. Graf F. Broly F. Hoffmann M. Probst U. A. Meyer PD Dr. H. Howald 《European journal of clinical pharmacology》1992,43(4):399-403
Summary The debrisoquine/sparteine-type polymorphism of drug oxidation and the polymorphism for acetylation are two common inherited variations in human drug metabolism. The phenotypes for hydroxylation and acetylation can be predicted be newly developed methods based on mutation-specific amplification of DNA by the polymerase chain reaction (PCR), which also allow for identification of heterozygous carriers of one mutant allele.In the present study, the results of genotyping of 81 healthy European volunteers were compared with the phenotype obtained by the classical biochemical approach using debrisoquine and caffeine as probe drugs.Genotyping correctly predicted all 73 extensive metabolisers (EMs) and 6 out of 8 poor metabolisers (PMs) of debrisoquine. All 48 rapid acetylators and 33 of 35 slow acetylators were predicted.Overall, the DNA analysis result matched the in vivo phenotype in 97.5 % of individuals. 相似文献
22.
23.
去痛片中四组分的HPLC测定 总被引:4,自引:0,他引:4
季申 《中国医药工业杂志》1997,28(10):455-457
以十八烷基硅烷键合硅胶为固定相,采用HPLC法测定去痛片中氨基比林、非那西丁、咖啡因、苯巴比妥的含量。各组分的回收率分别为99.8±0.50%、99.7±0.76%、99.3±0.54%、99.6±0.58%。 相似文献
24.
对经 HBV-DNA 转染的 MT-5细胞的培养条件进行观察。发现重金属离子Zn 和 Cd 对 MT-5细胞表达 HBsAg 有诱导作用,而咖啡因、地塞米松、氢化可的松、丙酸睾丸酮、苯丙酸诺龙对 MT-5细胞的 HBsAg 均无诱导作用。 相似文献
25.
W. C. L. FORD J. M. REES E. A. McLAUGHLIN L. LING M. G. R. HULL 《International journal of andrology》1994,17(4):199-204
The number of cryopreserved human spermatozoa which penetrated zona-free hamster oocytes afier stimulation with 2μmol A23187 per litre was increased by the hrther addition of 0.6 or 3.6 mmol pentoxifjrlline per litre. With spermatozoa prepared by washing by repeated centrifugation, the median numbers of sperm headd/egg were 1.9, 7.9 and 10.8 in the presence of 0, 0.6 or 3.6 mmol pentoxifylline per litre, respectively. A similar effect was observed with spermatozoa prepared on a Percoll gradient. As A23187 inhibited sperm motility, and this was exacerbated by pentoxifylline, the increased penetration rate of hamster oocytes cannot be explained by improved sperm motility. The number of spermatozoa stimulated to acrosome react by 2 μmol A23187 per litre was increased 3-fold by 3.6 mmol pentoxifylline per litre and 4-fold by 5 mmol caffeine per litre. These data suggest that CAMP may act synergistically with Ca2+ to stimulate the acrosome reaction. Pentoxifjrlline may improve the fertility of poor-quality human spermatozoa by enhancing their ability to respond to the Ca2+ signal produced by binding to the zona pellucida. 相似文献
26.
The effects of single oral doses of ketoconazole 400 mg and terbinafine 500 mg on the hepatic microsomal system have been investigated in 8 healthy male volunteers. Microsomal activity caffeine was assessed by following the metabolism of 3 mg/kg bodyweight i.v. administered 1 h after the drug. The inhibitory effect of terbinafine was more pronounced than that of ketoconazole: clearance was decreased from 1.34 ml.kg-1.min-1 in controls to 1.06 and 1.21 ml.kg-1.min-1, respectively, and the corresponding half-life was increased from 5.8 h in controls to 7.6 and 6.7 h, respectively. The apparent volume of distribution remained unchanged. The serum levels of the antimycotics were within the therapeutic range in each subject. Although all three substances are metabolised by microsomes, the kinetic parameters (Cmax, half-life, elimination constant) of the antimycotics were poorly if at all correlated with the elimination of caffeine. 相似文献
27.
D. M. Jackson C. E. Wallsten E. Jerning P.-S. Hu A. M. Deveney 《Psychopharmacology》1998,139(4):300-310
The aim was to study firstly, the motor effects of a new 5-HT1A antagonist, NDL-249 [(R)-3-(N-cyclopentyl-N-propylamino)-8-fluoro-3,4-dihydro-2H-1-benzopyran-5-carboxamide hydrochloride] and of the reference 5-HT1A antagonist WAY-100 635 [N-(2-(1-(4-(2-methoxyphenyl)piperazinyl))ethyl)-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride], in comparison to the 5-HT1A agonist (±)-8-OH-DPAT [(8-hydroxy-2-(di-N-propylamino) tetralin, hereafter 8-OH-DPAT], in rats acclimatised to the automated activity cages; secondly, to study whether
the behavioural effects of NDL-249 and 8-OH-DPAT are sensitive to the 5-HT depleting effects of p-chlorophenylalanine (PCPA); thirdly, to characterise the nature of the antagonist-induced activation seen in the automatic
activity cages with the aid of a behavioural observation analysis; fourthly, to examine the interaction between the 5-HT1Areceptors mediating the behavioural effects and dopamine (DA) receptors. NDL-249 was found to bind in vitro to rat hippocampal
5-HT1A receptors with high affinity and selectivity. In second messenger studies, it was devoid of agonist-like effects. In the
locomotor activity studies, each antagonist significantly increased the incidence of horizontal activity, peripheral activity
and rearing. 8-OH-DPAT, while significantly increasing peripheral and horizontal activities, decreased the incidence of rearing.
PCPA blocked the motor effects of NDL-249 but did not affect those of 8-OH-DPAT. Observational analyses indicated that NDL-249
induced significant increases at one or more doses in sniffing, rearing and locomotion together with a significant reduction
in stillness. WAY-100 635 significantly increased the incidence of rearing, intense grooming and vacuous chewing. The significant
increases in sniffing, grooming and intense grooming and the significant decrease in stillness induced by the DA D1 agonist, SK&F 38393 [(±)-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrochloride], were not altered by concomitant
pre-treatment with NDL-249. Pre-treatment of rats with either the DA D1 antagonist SCH-23390 (2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol) or the DA D2 antagonist, raclopride, blocked the reduced stillness and increased sniffing and rearing induced by NDL-249. In conclusion,
5-HT1A antagonists including the new selective antagonist, NDL-249, induce mild behavioural activation in rats, which is mediated
probably indirectly via DA systems.
Received: 3 April 1997/Final version: 23 February 1998 相似文献
28.
CYP1A2 activity, gender and smoking, as variables influencing the toxicity of caffeine 总被引:2,自引:2,他引:0
We have investigated several factors that might be related to the occurrence of toxic effects during the performance of a urinary test with caffeine (300 mg p.o), in 120 healthy volunteers. A total of 218 toxic effects were self-reported by eighty-two (68%) subjects. Females and nonsmokers were at the highest risk (chi-square test, P =0.01). Furthermore, two nonsmoking females experienced a symptomatology with delirium, restlessness, muscle tremor, vomiting and wakefulness. Among females and nonsmokers, those subjects who experienced toxic effects had lower caffeine N3-demethylation index (CYP1A2 activity) compared with unaffected females (1.87±0.51 vs 1.47±0.27, P <0.0005) and nonsmokers (1.69±0.23 vs 1.49±0.31, P <0.02). Caffeine N1- and N7-demethylations indices were also lower among females ( P <0.0005) and nonsmokers ( P <0.02) who reported toxic symptoms. We conclude that CYP1A2 activity, gender and smoking are variables to be considered as influencing the toxicity of caffeine. 相似文献
29.
Sala G Maspotch S Iturriaga H Blanco M Cerda V 《Journal of pharmaceutical and biomedical analysis》1988,6(6-8):765-772
This work deals with the UV spectrophotometric quantitation of a mixture of compounds with overlapped spectra. The mixture spectrum is resolved by use of three computational programs based on different algorithms, namely Multicomponent Analysis (commercial software available from Hewlett-Packard), MULTIC (relying on multiple regression analysis) and SIMPLEX. The results obtained for mixtures of acetylsalicylic acid, acetaminophen and caffeine in commercial analgesic formulations, are compared. 相似文献
30.
Farah Isse Mumin Benjamin Obukowho Emikpe Michael Ayodele Odeniyi 《Journal of immunoassay & immunochemistry》2020,41(3):311-321
ABSTRACTA study was conducted to evaluate mucoadhesive property and immunomodulatory effect of phytogenic gums from Boswellia frereana, Boswellia carteri andCommiphora myrrha on intranasal Peste des petits ruminants (PPR) vaccination in goats and sheep in an ex-vivo and in-vivo situations. Plant gums were purified, dried and compressed into 500gm tablets. Modified shear stress measurement technique was used on freshly excised trachea and intestine tissues of goat to measure peak adhesion time. Forty eight animals (24 goats and 24 sheep) were divided into eight groups (of 3 goats and 3 sheep) and immunized intranasally with gum-vaccine combinations in two ratios (1:1, 1:2). Antibody against PPR virus was measured on day 14, 28, 42 and 56 post vaccination using H-based PPR bELISA. The peak adhesion time of the different gums was transient. PPR virus antibodies were detected in all immunized goats and sheep but not in unvaccinated control. The best percentage inhibition was recorded for Boswellia carteri-vaccine combination group at a ratio of 1:1. Administration of Boswellia carteri-PPR vaccine combination through intranasal or subcutaneous route, elicited similar antibody titre, implying that the intranasal route may be used as a non-invasive alternative delivery in PPR vaccination of small ruminants. 相似文献