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81.
人参根及茎叶皂苷 50~200 mg/kg能使群养小鼠的自发运动量明显增加,8周隔离饲育小鼠比群养小鼠自发运动量明显增加,人参根皂苷能使其剂量依赖性降低,而人参茎叶皂苷影响不明显;对戊巴比妥钠所致睡眠试验中,隔离孤独饲育小鼠比群养小鼠睡眠时间明显缩短(t=4.356,P<0.001)。人参根皂苷 50~200 mg/kg使孤独饲育小鼠的睡眠时间随剂量增加而延长,200 mg/kg组与对照组比较,t=3. 665,P<0.01。并能使 8周隔离饲育的小鼠 20 min内连续攻击时间有意义地下降(t=4.540,P=0.001),但人参茎叶皂苷效果不明显。证明人参根及茎叶皂苷具有中枢兴奋作用,同时人参根皂苷还具有中枢镇静作用。 相似文献
82.
Anhedonia, the inability to experience pleasure, and observed changes in psychomotor performance are frequent psychopathological phenomena in major depression with possible common neurobiological mechanisms. Interest, pleasure and reactivity to pleasurable stimuli contribute to movement generation and observable behaviour. Therefore the relationship between anhedonia and psychomotor retardation was studied in 48 depressed patients. Subjectively experienced anhedonia correlated with self-rated but not with observer-rated global severity of depression. There was a significant correlation between anhedonia and psychomotor retardation assessed with the Widlöcher Retardation Scale. The results suggest the existence of an empirical relationship between reduced ability to experience pleasure and observable psychomotor retardation in depression. Specific measures of psychomotor phenomena may provide further insights into the relationship between observable behaviour and self-experienced symptoms in depression. 相似文献
83.
Previous maternal experience potentiates the effect of parturition on oxytocin receptor mRNA expression in the paraventricular nucleus 总被引:1,自引:0,他引:1
Broad KD Lévy F Evans G Kimura T Keverne EB Kendrick KM 《The European journal of neuroscience》1999,11(10):3725-3737
In sheep, central oxytocin release at parturition induces maternal behaviour which is thought to be mediated by changes in the expression of central oxytocin receptors. The distribution, effects of parturition, previous maternal experience and hormonal status on the distribution of an oxytocin receptor was investigated using immunocytochemistry and in situ hybridization. In ewes with no previous maternal experience, parturition induced significant increases in oxytocin receptor mRNA expression in the anterior olfactory nucleus, medial preoptic area, ventromedial hypothalamus, lateral septum, medial amygdala, bed nucleus of the stria terminalis and diagonal band of Broca. In maternally experienced ewes, parturition induced additional increases in two areas, the paraventricular nucleus and the Islands of Calleja. The changes in progesterone and oestrogen that occur during late pregnancy and parturition appear to contribute to increases in expression in the anterior olfactory nucleus, Islands of Calleja, medial preoptic area, ventromedial hypothalamus, bed nucleus of the stria terminalis and diagonal band of Broca, but not in the paraventricular nucleus, lateral septum and medial amygdala. These results demonstrate that progesterone and oestrogen priming enhance oxytocin receptor mRNA expression in a number of regions in the olfactory system, hypothalamus and limbic brain. These effects appear to be independent of maternal experience. Parturition increases oxytocin receptor mRNA expression in all the areas influenced by hormonal priming and the lateral septum, medial amygdala and paraventricular nucleus. Maternal experience also enhances expression of oxytocin receptor mRNA in the paraventricular nucleus and the Islands of Calleja. Because the paraventricular nucleus is the main source of oxytocin release in the brain, this upgrading of autoreceptors as a result of maternal experience may serve to enhance release of this peptide in projection sites regulating maternal behaviour. 相似文献
84.
Amelia Rodríguez Martín José Manuel Martínez Nieto Miguel Angel Ruiz Jiménez José Pedro Novalbos Ruiz M. Carmen Díaz Vázquez Yamin Chocrón Fernández Miguel Angel Rendón Gómez Carmen Cano Fernández 《European journal of epidemiology》1999,15(7):643-648
In recent years, eating disorders (Anorexia and Bulimia Nervosa) have increased and are appearing at increasingly younger ages. They affect predominantly adolescent females 12 to 25 years of age. The objective of this study of adolescents is to detect and discuss unhealthy eating behaviour, defined by either of two factors: (1) following a slimming diet not advised or supervised by any person trained in health care; or (2) eating very large quantities at irregular times, not related to anxiety or stress. A transversal study has been undertaken of 630 school children of 14–18 years of age (average: 15.9 years) in Cádiz (Andalucia, Spain), using an anonymous self-reporting questionnaire to collect data on personal and educational situation, on eating habits, on nutritive intake and knowledge of nutrition, and on dieting and physical exercise. The study has considered averages, ratios, statistical significance (x
2) and, as a measure of risk, the Disequality Ratio of Prevalence (DRP). Anomalous eating behaviour was detected in 46.3% (292), with females predominant by a ratio of 2:1. Comparing groups with anomalous and with normal eating habits, significant differences were detected in respect of: perception of body image (p<0.001), frequency of weighing oneself (p<0.05), periods of abstinence from eating (DRP 1.66; 95% confidence interval (CI): 1.66–2.37), provocation of vomiting (DRP 2.02; 95% CI: 1.13–3.65), use of laxatives (DRP 4.25; 95% CI: 1.08–9.63), and the exclusion of certain meals and types of food, mainly bread and cereals, fats and sugars. Conclusions are drawn on the substantial scale of unhealthy eating behaviour among adolescents in Cadiz. More adequate education on personal health and related social issues should be provided. 相似文献
85.
Gerhard Scherer 《Psychopharmacology》1999,145(1):1-20
Rationale: Compensation or compensatory smoking, accurately defined, deals with the question of whether switching to cigarette brands
with different smoke yields is associated with a change in smoke uptake proportional to the change in machine-derived yields.
The issue of compensation is important because it bears on whether switching to ”lighter” brands means lower overall smoke
intake or not. Objectives: The present review investigated whether and to what extend low yield cigarettes are smoked more intensively. In addition,
published data on whether nicotine, ”tar”, or any other smoke constituent or property influence compensational smoking are
summarized. Methods: The studies on compensation were classified as follows: (1) studies on smoking behaviour in relation to cigarette yields
(with and without brand switching); (2) studies on compensation for nicotine (switching between cigarettes which differ ”only”
in their nicotine yield, nicotine supplementation, manipulation of renal nicotine excretion, administration of nicotine agonists
or antagonists); (3) studies on compensation for other factors (influence of tar, taste, irritation, draw resistance). In
order to quantify the degree of compensation, an index is defined and applied to selected brand switching studies. This compensation
index determines, in relative units, the degree to which a smoker responds to a change in smoke yields with a change in smoke
uptake measured by suitable biomarkers. The role of vent blocking is also briefly discussed. Results: Most of the studies which compare the smoking behaviour when smoking cigarettes with different smoke yields supply evidence
for ”partial” compensation, suggesting that cigarettes with lower yields are smoked more intensively than those with higher
yields. These studies also show that a change in the daily number of cigarettes is not a common mechanism of compensation.
Effective vent blocking during smoking is a rare event and can therefore also be regarded as an uncommon mechanism of compensation.
Evaluation of a suitable subset of brand-switching studies revealed an average compensation of 50–60% of the nicotine yield.
Compensation tended to be more complete when changing to cigarettes with higher yields than when changing to cigarettes with
lower yields. In general, brand-switching studies do not supply information on the underlying causal factors responsible for
compensatory smoking. Results of the nicotine supplementation studies are not conclusive: some report evidence of nicotine
titration, others do not. A general problem with this type of investigation is that continuous nicotine application does not
mimic the spike-wise application with cigarette smoking, and may lead to nicotine tolerance. There is limited evidence that
cigarettes were smoked more intensively when the urinary clearance of nicotine was increased. A small number of studies provide
some evidence that smoking intensity increased after smokers were administered a nicotine antagonist. Several reports indicate
that tar, taste and sensory properties of the smoke as well as the draw resistance of the cigarette may play a role in compensatory
smoking. Low-yield cigarettes usually have reduced pressure drops which smoke researchers have suggested leads to increased
puff volume. This effect seems to be independent of the smoke yield of the cigarette. There is also some evidence that some
smokers maintain a consistent pattern of smoking which works independent of any changes in nicotine or tar yields, taste or
design features of the cigarette (”functional autonomy”). Conclusions: The available data suggest that smokers partially compensate for a different smoke yield. While the factors and their interaction
responsible for compensational smoking are not fully understood, there are data suggesting that a subgroup of smokers may
partially compensate for nicotine. Even in this subgroup of smokers, however, the relative importance of the pharmacological
versus the sensory effects of nicotine in smoke remains to be determined.
Received: 4 January 1999 / Final version: 22 March 1999 相似文献
86.
T. J. De Vries Anton N. M. Schoffelmeer R. Binnekade Louk J. M. J. Vanderschuren 《Psychopharmacology》1999,143(3):254-260
Rationale: The neurobiological mechanisms underlying the persistence of drug craving in detoxified addicts are still poorly understood.
Objective: The present study was designed to evaluate dopaminergic mechanisms in drug-seeking behaviour following long-term (>3 weeks)
extinction of IV drug self-administration in rats. Methods: To that end, we studied the effects of direct and indirect dopamine (DA) agonists on reinstatement of previously extinguished
responding for heroin (50 μg/kg per injection; 14–15 daily 3-h sessions) and cocaine (500 μg/kg per injection; 10–11 daily
2-h sessions). Results: In animals with a cocaine history, priming with cocaine, the selective DA reuptake inhibitor GBR-12909 and the DA D2 receptor agonist quinpirole resulted in robust and selective reinstatement of non-reinforced nose poking behaviour in the
previously drug-paired hole. In contrast, the D1 agonist SKF-82958 failed to reinstate responding and the non-selective DA agonist apomorphine even suppressed responding
in these animals. In heroin-trained rats, heroin and GBR-12909 strongly reinstated responding, whereas all direct DA agonists
were ineffective. Again, the two highest doses of apomorphine decreased responding in these animals. In a parallel study,
the ability of DA ligands to express behavioural sensitization in animals pretreated with amphetamine or morphine was evaluated.
Interestingly, all agonists that reinstated responding in the present study caused expression of locomotor sensitization and
vice versa. Conclusions: The differences between direct and indirect agonists indicate a clear, but complex, involvement of DA in drug-seeking behaviour
long after detoxification. Moreover, the results show an important role of D2 receptor activation in the persistence of cocaine- but not heroin-seeking behaviour. Finally, the results from both studies
suggest a relationship between drug-induced reinstatement and drug hyperresponsiveness in long-term abstinent rats.
Received: 14 May 1998 / Final version: 1 December 1998 相似文献
87.
BOB GATES 《Journal of clinical nursing》1996,5(1):7-12
- ? The purpose of this paper is to contribute to the debate on issues related to the reliability and validity of measurement of challenging behaviour (behavioural difficulties) in learning disability. A number of practical, theoretical and methodological issues are discussed that have significance for the nurse both as practitioner and/or researcher in learning disability. These issues are equally important to both provider and purchaser of health care in order that resources can be most effectively targeted.
- ? The term ‘challenging behaviour’ would appear to be used both in literature and research synonymously with behavioural difficulties, this has implications for nurses in both their clinical practice and/or research. The author concludes by identifying a need to replace the term challenging behaviour, with ‘behavioural difficulties’. It is argued that such a term is much more explicit in meaning and amenable to operational definition, thus enabling empirical study. Such a proposal will not be accepted by all as justifiable; this is because some might argue that adopting the term behavioural difficulties may be a retrograde step that perpetuates negative imagery and inappropriate labelling of people with a learning disability.
88.
DAVID NEWBOLD 《Journal of clinical nursing》1996,5(6):373-380
- ? Psychological stressors are said to be an important influence on the outcome of chronic illnesses such as rheumatoid arthritis (Engel, 1977).
- ? Helping patients to cope with stressors is identified as a central concept in the delivery of nursing care (Khan et al., 1994). It is thus reasonable to suggest that rheumatology nurses may be key players in the process of coping with rheumatoid arthritis.
- ? But in order for rheumatology nurses to be effective players in this process, they need to discourage coping behaviour(s) linked to poor outcomes, and/or promote an overall behaviour pattern linked to a better outcome. Literature showing the link between different coping behaviours and outcome is examined, and cognitive restructuring is emphasized as one method nurses could use.
- ? Having identified coping behaviour which is optimal in terms of future outcome, further study of different forms of coping-based educational intervention is suggested, to reveal how such patterns of behaviour can be taught by nurses in the most effective way
89.
Maria A. Annunziata Ph.D. Carlo Rossi M.D. Renato Talamini Sc.D. Salvatore Tumolo M.D. Silvio Monfardini M.D. 《Supportive care in cancer》1996,4(5):334-340
The aim of this study was to determine the influence of socio-demographic and professional factors on physicians' attitudes to the terminally ill. Between May 1992 and May 1993, a survey was conducted in the province of Pordenone (north-east, Italy) in order to analyse a number of specific issues, such as emotional involvement, the need for aggressive treatments and the communication of diagnosis and prognosis. After obtaining a list of board-certified physicians from the Medical Association office in Pordenone, a modification of the cancer questionnaire of Haley and Blanchard (QSPT) was mailed to 916 doctors. Of these, 605 (60%; 487 male, 118 female; mean age 41 ± 11 SD) returned the completed questionnaire. Within the group of responders, we identified three main subgroups, according to their type of activity: general practitioners (175, 29%), hospital doctors (235, 39%) and other doctors (195, 32%). In age, sex and activity, the only significant difference between responders and non-responders was age (mean age 41 and 43 years respeetively). Most of the responders (77%) stated that they were able to deal with the terminally ill patient and his/her needs; 44%, however, admitted that patients' anxiety is sometimes unbearable. For the vast majority of the doctors polled (91%), providing a comfortable environment for an incurable patient was more important than pursuing aggressive treatment, but only 44% were convinced of the uselessness of aggressive care. To the question on whether to disclose information about imminent death to allow patients to prepare spiritually, 37% answered No, 38% Yes, and 25% were uncertain. Almost all responders (95%), however, believed in the beneficial effect of hope on the terminally ill. Ourresults suggest that doctors' professional and, most of all, sociodemographic and cultural factors determine the relationship with the patient on both the emotional and the clinical decision-making levels. 相似文献
90.
R. Ortmann P. C. Waldmeier E. Radeke A. Felner A. Delini-Stula 《Naunyn-Schmiedeberg's archives of pharmacology》1980,311(2):185-192
Summary The behavioural syndrome caused by l-5-HTP in rats was used for the study of effects of selective 5-HT uptake inhibitors and inhibitors of MAO on central 5-HT receptors. A good correlation was found between the relative potencies of drugs in inhibiting the 5-HT uptake in the rat brain and in intensifying l-5-HTP-induced behavioural stimulation. The potentiation of the l-5-HTP syndrome by the MAO inhibitors correlated with the inhibition of the A- but not of the B-form of the brain monoamine oxidase.In rats treated with the maximally inhibiting dose of a 5-HT uptake inhibitor, MAO inhibitors were still able to increase the intensity of the l-5-HTP syndrome, while the combination of maximal doses of two 5-HT uptake inhibitors did not produce a more intense syndrome than that produced by one 5-HT uptake inhibitor alone.The l-5-HTP-induced behavioural syndrome in rats seems to afford an experimental model allowing the quantification and characterization of the interaction of drugs with serotonin metabolism in the brain. 相似文献