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71.
Zusammenfassung Die Aktivitäten der Enzyme Glutamat-Oxalacetat-Transaminase, Lactatdehydrogenase und Malatdehydrogenase wurden im Erythrozytenhämolysat und im Serum im Hinblick auf altersabhängige Veränderungen untersucht.In den Erythrozyten nehmen die Aktivitäten der Glutamat-Oxalacetat-Transaminase und Malatdehydrogenase bei zunehmendem Alter ab. Für die Lactatdehydrogenase ist dagegen ein leichter Anstieg zu verzeichnen.Statistisch signifikant unterschieden sich bei der Glutamat-Oxalacetat-Transaminase die Gruppen im Alter von 1–1041–50 und 31–4041–50 Jahren. Die übrigen Gruppierungen zeigten keine statistisch signifikante Differenz. Die im Serum gemessen E Enzymaktivitäten ließen im beobachteten Bereich keine statistisch signifikanten Differenzen erkennen. In der großen Streuung der intraerythrozytären Enzyme schen wir den Ausdruck einer individuell verschiedenen Enzymausrüstung der roten Blutkörperchen.
Herrn Prof. Dr. W.Wachsmuth zum 65. Geburtstag gewidmet. 相似文献
Summary The activity of the enzymes glutamate-oxaloacetate-transaminase, lactate dehydrogenase and malate dehydrogenase was tested in red cell hemolysates and in serum for age-dependent changes.In the red cells the activity of glutamate-oxaloacetate-transaminase and malate dehydrogenase decreases with increasing age. Lactate dehydrogenase on the other hand shows a slight increase.Statistically significant differences were found for glutamate-oxaloacetate-transaminase in the age groups of 1–1041–50 and 31–4041–50 years. The other groups did not show a statistically significant difference. Enzyme activity, determined in serum did not show a statistically significant difference in the tested range. In the great number of enzymes within the red cell we see an expression of the individually varied enzyme composition of red cells.
Herrn Prof. Dr. W.Wachsmuth zum 65. Geburtstag gewidmet. 相似文献
72.
73.
OBJECTIVE: The purpose of the study was to examine whether caffeine dependence and a family history of alcoholism are associated with continued use of caffeine during pregnancy. METHOD: Forty-four women seeking obstetrical care in an office-based practice completed questionnaires and provided saliva samples at three prenatal visits occurring 2-3, 3-4, and 7 months postconception. On visit 1, the patients received the physician's instructions to stop using caffeine. Structured interviews were used to assign a diagnosis of caffeine dependence (lifetime) and to identify family history of alcoholism. Outcome measures included self-reported levels of caffeine use and saliva caffeine levels at the three prenatal visits. RESULTS: Although most women eliminated or substantially reduced their caffeine consumption between pregnancy awareness and prenatal visit 1, those with a lifetime diagnosis of caffeine dependence and a family history of alcoholism had higher levels of caffeine use and lower rates of abstinence throughout pregnancy. Saliva caffeine levels confirmed these effects. Withdrawal symptoms, functional impairment, and craving were cited as reasons they failed to eliminate or cut back on caffeine use. Fifty percent of the women with both a lifetime diagnosis of caffeine dependence and a family history of alcoholism continued to use caffeine in amounts (>300 mg/day) greater than those considered safe during pregnancy, compared to none of the women without caffeine dependence and a family history of alcoholism. Women with a lifetime diagnosis of caffeine dependence and a family history of alcoholism also reported higher rates of past cigarette smoking and problematic alcohol use. CONCLUSIONS: Caffeine-dependent women with a family history of alcoholism were not able to follow their physician's advice to reduce or eliminate caffeine consumption during pregnancy, despite their wanting to do so. This subgroup may require more intensive intervention to ensure caffeine abstinence and may be at greater risk for abuse of or dependence on other drugs. 相似文献
74.
Cognitive performance in untreated early onset gender identity disorder (GID) patients might correspond to their born sex and not to their perceived gender. As a current mode of intervention, cross-sex hormone treatment causes considerable physical changes in GID patients. We asked, as has been suggested, whether this treatment skews cognitive performance towards that of the acquired sex. Somatically healthy male and female early onset GID patients were neuropsychologically tested before, 3 and 12 months after initiating cross-sex hormone treatment, whereas untreated healthy subjects without GID served as controls (C). Performance was assessed by testing six cognitive abilities (perception, arithmetic, rotation, visualization, logic, and verbalization), and controlled for age, education, born sex, endocrine differences and treatment by means of repeated measures analysis of variance. GID patients and controls showed an identical time-dependent improvement in cognitive performance. The slopes were essentially parallel for males and females. There was no significant three-way interaction of born sex by group by time for the six investigated cognitive abilities. Only education and age significantly influenced this improvement. Despite the substantial somatic cross-sex changes in GID patients, no differential effect on cognition over time was found between C and GID participants. The cognitive performance of cross-sex hormone-treated GID patients was virtually identical to that of the control group. The documented test–retest effect should be taken into consideration when evaluating treatment effects generally in psychiatry. 相似文献
75.
Clinical trial registration: a statement from the International Committee of Medical Journal Editors
76.
Rønsen O Børsheim E Bahr R Klarlund Pedersen B Haug E Kjeldsen-Kragh J Høstmark AT 《Scandinavian journal of medicine & science in sports》2004,14(1):39-48
The purpose of this study was to characterize the extent of immune, endocrine, substrate and metabolic changes during a long-distance cross-country ski race in extremely well-trained athletes and evaluate if the blood perturbations would indicate signs of health risk. Ten male (M) and six female (F) national team skiers were investigated as they followed their usual routines of race preparations. Blood samples were drawn before and immediately after a World Cup 50-km M and 30-km F ski race with a mean finish time of 142 and 104 min, respectively. Hemoglobin, electrolytes, and C-reactive protein remained unchanged for both M and F. Serum testosterone remained unchanged in M, but doubled in F. Significant increases were observed in concentrations of granulocytes (F: 5 x, M: 5 x), natural killer cells (F: 2 x, M: 1.5 x), adrenaline (F: 12 x, M:10 x), noradrenaline (F: 7 x, M:5 x), growth hormone (F: 30 x, M: 2 x), cortisol (F: 1.5 x, M:2 x), glucose (F: 2 x, M:1.5 x), creatine kinase (F: 2 x, M:2 x), uric acid (F: 1.5 x, M: 1.5 x) and non-organic phosphate (F:2 x, M:2 x), while insulin concentration decreased (F: 0.5x, M: 0.8 x). Free fatty acid (FFA) concentration increased (F:2 x, M: 3 x). In conclusion, we observed substantial changes in several immuno-endocrine, substrate and metabolic measurements after long distance cross-country ski racing and suggest that some of these marked changes may reflect the large amount of muscle mass involved during skiing. 相似文献
77.
Volz T Schwarz G Fleckenstein B Schepp CP Haug M Roth J Wiesmüller KH Dannecker GE 《Human immunology》2004,65(6):594-601
Juvenile idiopathic arthritis (JIA) is considered to be an autoimmune disease. Various human leukocyte antigen (HLA) associations for different subgroups of this heterogeneous disease have been found. For early-onset pauciarticular arthritis (now oligoarthritic JIA), a strong association with the HLA class II haplotype DQA1*0401/DQB1*0402 (DQ4) has been described. We determined the peptide-binding specificities of this HLA-DQ molecule by screening a synthetic acetylated nonapeptide amide library with one defined and eight random sequence positions. A characteristic binding motif could be deduced. By use of these data, we designed defined specific nonapeptides and identified high-affinity ligands binding to HLA-DQ4. The peptide binding motif of HLA-DQ4 is very similar to the motif of HLA-DQ7, also associated with oligoarthritic JIA. It is, however, different from binding motifs of neutral or protective HLA-DQ molecules. Our results further support the idea of differential peptide presentation in the pathogenesis of oligoarthritic JIA. 相似文献
78.
Clinical trial registration: a statement from the International Committee of Medical Journal Editors
79.
Clinical trial registration: a statement from the International Committee of Medical Journal Editors 总被引:16,自引:6,他引:10
80.
DeAngelis C Drazen JM Frizelle FA Haug C Hoey J Horton R Kotzin S Laine C Marusic A Overbeke AJ Schroeder TV Sox HC van der Weyden MB;International Committee of Medical Journal Editors 《Nederlands tijdschrift voor geneeskunde》2004,148(38):1870-1871
Altruistic motives and trust are central to scientific investigations involving people. These prompt volunteers to participate in clinical trials. However, publication bias and other causes of the failure to report trial results may lead to an overly positive view of medical interventions in the published evidence available. Registration of randomised controlled trials right from the start is therefore warranted. The International Committee of Medical Journal Editors has issued a statement to the effect that the 11 journals represented in the Committee will not consider publication of the results of trials that have not been registered in a publicly accessible register such as www.clinicaltrials.gov. Patients who voluntarily participate in clinical trials need to know that their contribution to better human healthcare is available for decision making in clinical practice. 相似文献