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81.
为更好地了解流动儿童计划免疫管理现况,1997年海南省组织了专题调查,发现流动儿童以县内流动为主,流动儿童上卡率为76.6%,五苗接种率分别为卡介苗69.4%,脊灰糖丸65.1%,百白破63.6%,麻疹59.9%,HBV56.9%,均远未达到目标要求,脊达抗体GMT流动儿童为1:153.20,常住儿童为1:243.61,两者有显著性差异,这表明,加强流动儿垢计划免疫管理,最今后计免工作的重点和难点 相似文献
82.
Benefits of training at moderate altitude versus sea level training in amateur runners 总被引:4,自引:0,他引:4
M. Burtscher W. Nachbauer P. Baumgartl M. Philadelphy 《European journal of applied physiology》1996,74(6):558-563
After more than 25 years of research on altitude training (AT) there is no consensus regarding either the training programme
at altitude or the effects of AT on performance at sea level. Based on a review of the research work on AT, we investigated
combined base training and interval training at moderate altitude and compared immediate and delayed effects on sea level
performance with those following similar sea level training (SLT). The altitude group (AG, 10 male amateur runners) trained
at 2315 m (natural altitude) and the sea level group (SLG, 12 male amateur runners) at 187 m. Both groups performed 7 days
of base training (running on a trail) lasting between 60 and 90 min a day and 5 days of interval training (speed and hill
runs) for between 10 and 45 min a day. Incremental exercise tests were performed 1 week before (t
1), 3 days after (t
2) and 16 days after (t
3) the 12-day main training period. Within AG, exercise performance improved fromt
1 tot
2 by 8% (P<0.05) and fromt
2 tot
3 by 8% (P<0.05). Maximum oxygen uptake (
) increased fromt
2 tot
3 by 10% (P<0.05). Within SLG exercise performance increased fromt
2 tot
3 by 8% (P<0.05). Att
3, relative and absolute
in AG were significantly higher in comparison with SLG (P=0.005 andP=0.046 respectively). The improved performance 3 days after AT may be explained in part by an increased oxygen uptake at submaximal
exercise intensities without a change in
. Further enhancement in performance 2 weeks after AT, however, seems to have been due to the clearly enhanced
. Progressive cardiovascular adjustments might have contributed primarily to the time-dependent improvements observed after
AT, possibly by an enhanced stroke volume overcompensating the reduced heart rates during submaximal exercise. In conclusion,
our findings would suggest that training at a moderate natural altitude improves performance at sea level more than SLT. Combining
base and interval training with regulation of intensity by training at constant heart rates during acclimatization at altitude
would seem to be a successful training regimen for amateur runners. Most beneficial effects became apparent during the subsequent
SLT around 2 weeks after return from altitude. Therefore, we are convinced that AT should be reconsidered as a potent tool
for enhancing aerobic capacity, at least in non-elite athletes. 相似文献
83.
W. Fröscher M. Eichelbaum R. Gugler G. Hildenbrand H. Penin 《Journal of neurology》1981,224(3):193-201
Summary To evaluate whether knowledge of plasma levels of anti-epileptic drugs has an effect on therapeutic outcome, 127 epileptic outpatients were randomly assigned to two groups (A and B). Plasma levels of group A were reported to the treating physician who attempted to keep the plasma levels within the therapeutic range. The treating physician was not informed of the results of plasma lavel determinations of group B. Data from 105 patients were available for assessment at the end of the study year. Therapeutic results of groups A and B were not significantly different. The reduction in seizure frequency was associated with an increase in plasma concentrations of the anti-epileptic drugs. Thus, under the conditions of the study, knowledge of plasma levels of anti-epileptic drugs did not further improve therapeutic results.
Zusammenfassung Um festzustellen, ob die Kenntnis des Plasmaspiegels der Antiepileptika das Therapieergebnis verbessern kann, wurden 127 ambulant behandelte Patienten mit Epilepsie in randomisierter Reihenfolge in zwei Gruppen eingeteilt (A und B). Die Plasmaspiegel der Antiepileptika in Gruppe A wurden dem behandelnden Arzt mitgeteilt, der versuchen sollte, die Plasmaspiegel in den Therapeutischen Bereich zu bringen. Die Ergebnisse der Plasmaspiegelbestimmung in Gruppe B (Kontrollgruppe) wurden dem behandelnden Arzt nicht mitgeteilt. Am Ende des Untersuchungsjahres konnten die Daten von 105 Patienten ausgewertet werden. Das Behandlungsergebnis von Gruppe A und von Gruppe B war am Ende des Beobachtungsjahres nicht signifikant verschieden. Die Abnahme der Anfallshäufigkeit ging mit einem Anstieg der Plasmakonzentration der Antiepileptika einher. Somit konnte unter den Bedingungen dieser Studie das Therapieergebnis durch die Kenntnis der Plasmaspiegel der Antiepileptika nicht weiter verbessert werden.相似文献
84.
Perspectives on rapid elimination and ultimate global eradication of paralytic poliomyelitis caused by polioviruses 总被引:2,自引:0,他引:2
A. B. Sabin 《European journal of epidemiology》1991,7(2):95-120
Poliomyelitis caused by polioviruses has already been eradicated from industrialized countries of North America, Europe, Asia and Oceania, but the procedures by which this eradication was achieved are not adequate for the poor tropical and subtropical countries. The major challenge now is first to eliminate it rapidly from Asia and Africa where an estimated 250,000 cases and 25,000 deaths currently occur annually. The great progress toward eradication of wild polioviruses from poor tropical and subtropical countries in Latin America was achieved not by the procedures still recommended by the WHO Expanded Program on Immunization (EPI) but by the independently organized annual, national days of antipolio vaccination — all based on the use of large armies of well-trained non-professional, community volunteers — first used in Cuba (1962), Brazil (1980), Nicaragua (1981), Dominican Republic (1983), Paraguay (1985), and Mexico (1986). This novel approach, described in some detail in this communication, is recommended for the rapid elimination of wild polioviruses from Asia and Africa, and for ultimate global eradication with the help of a special cadre within the EPI of WHO. The extensive use by the Pan American Health Organization (PAHO) of highly sophisticated regional virus laboratories has led to the recognition that, in areas from which poliomyelitis caused by polioviruses has been largely eliminated, there are thousands of cases of acute flaccid paralysis, previously clinically diagnosed as probable poliomyelitis, that have no viral etiology, a phenomenon previously reported by Dr. Manuel Ramos Alvarez in Mexico City in 1967. 相似文献
85.
Endothelin is a peptide reported to be one of the most potent vasoconstrictors known. Presumably, endothelin could play a role in the physiological regulation of blood pressure in healthy or hypertensive people. We have studied a normal restriction fragment length polymorphism (RFLP) at the endothelin-I (EDN1) locus detected with the restriction enzyme TaqI. In three different series comprising 166, 120 and 207 unrelated individuals, we found no evidence for association between genotype in this polymorphism and level of systolic or diastolic blood pressure. In two series of 156 and 117 monozygotic (MZ) twin pairs, respectively, there was no difference between genotypes in within-pair variation in systolic or diastolic blood pressure. Thus neither "level gene" nor "variability gene" effects of normal genes at the EDN1 locus could be detected with the polymorphism analyzed, in healthy population samples. 相似文献
86.
H. Liedholm E. Wåhlin-Boll A. Hanson I. Ingemarsson A. Melander 《European journal of clinical pharmacology》1982,21(5):417-419
Summary The concentrations of real and apparent (= real hydralazine + acid-labile hydrazones) hydralazine in maternal and umbilical plasma obtained at delivery of 6 women treated with hydralazine and atenolol for pregnancy hypertension were measured by gas chromatography. In one of the patients, the concentrations of the same substances were subsequently measured in breast milk. Apparent hydralazine reached higher levels in umbilical than in maternal blood. The concentration of real hydralazine seemed to be at least as high in the fetus as in the mother. On the other hand, even though the fraction of real (i.e. presumably active) hydralazine was greater in milk than in plasma, the total concentration was smaller, and the estimated dose per milk feed of 75ml would not exceed 0.013mg. Thus, hydralazine treatment of the pregnant woman would expose her fetus to effective concentrations of the drug, but breast feeding would not result in a clinically relevant concentration in the infant. 相似文献
87.
Summary Chronic treatment with conventional lithium carbonate was interrupted in a selected group of 40 psychiatric patients of mixed sex and race. All patients had normal renal function. Serum samples were taken 12, 24, 36 and 48 h after the last dose and lithium was assayed by atomic absorption spectrophotometry. Decay rates calculated for the 12–24 h and 36–48 h periods yielded different values. This was ascribed to the presence of an incomplete redistribution phase during the earlier period. The distribution of elimination rates determined during the later period gave a more symmetrical spread and approximated a normal distribution. The mode, median, mean and standard deviation of the lithium elimination half-lives were 12.5, 14, 18.2 and 7.3 h and 22.5, 24.5, 29.8 and 10.1 h for the two periods, respectively. The results contrast sharply with another report of the distribution spread of elimination half-lives in a much larger sample. The current values have implications for dosage prediction, serum level monitoring and dosage formulation, especially sustained-release preparations. The evidence was against the possibility that some individuals retain lithium. 相似文献
88.
R. L. Zielhuis F. W. van der Kreek 《International archives of occupational and environmental health》1979,42(3-4):191-201
Summary When adequate human observations are not or scarcely available, permissible levels for occupational exposure have to be extrapolated from animal experiments. Taking into account experimental conditions, e. g., duration of exposure ( 3 months), animal species, knowledge of no- (adverse-) effect level or minim al-(adverse-) level, presence of data on human observations, the authors worked out a procedure for extrapolation. This procedure should only be applied for systemic non-carcinogenic effects. The proposed procedure is to be regarded as tentative and as suggestion for international discussion.The evaluation starts with a safety factor = 10 for extrapolation from dose/kg b. w. in long-term animal experiments to exposure of adult workers (40 h/wk); this factor corresponds to a safety factor = 3–10 for extrapolation from doses presented as concentrations in air. If long-term experimental exposure is 24 h daily, the safety factor can be lowered to the minimum value of 1. If only short-term exposure studies are available, the safety factor may have to be increased to a maximum of 400. 相似文献
89.
Summary Plasma-levels of thioridazine, mesoridazine, sulphoridazine and two other metabolites were determined in ten older chronic psychotic patients on thioridazine therapy. The plasma-level before the morning dose of thioridazine was the most reliable parameter for clinical studies. An intra-individual relationship between lower doses of thioridazine and plasma-levels was found. The percentage contribution of psychoactive compounds to the total sum of thioridazine plus metabolites ranged from 43–74%. The mean early disappearance half-life of thioridazine was 5 hours, and its mean late disapperance half-life was 26 hours. 相似文献
90.
马鬃蛇醇提物对大鼠血清性激素水平的影响 总被引:2,自引:0,他引:2
目的:研究马鬃蛇醇提物对大鼠血清性激素水平的影响。方法:用放射免疫法测定大鼠血清中睾酮、雌二醇及FSH含量。结果:马鬃蛇醇提物可提高正常雄性大鼠血清睾酮(T)水平,对环磷酰胺所致雄性大鼠生殖统损伤引起的睾酮水平下降也有提高趋势;对环磷酰胺所致雌性大鼠系统损上起的雌二醇水平下降有明显的提高作用,对正常雌性大鼠血清雌二醇(E2)有一定的升高趋势;对FSH有一定的降低作用,结论:马鬃蛇醇提物可提高大鼠血清T、E2水平,有降低FSH水平趋势,提示有性激素样作用。 相似文献