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2.
我们对30例住院病人用荧光分光光度法测定了不同烧伤时间、不同烧伤指数(BI)血儿茶酚胺类(CA)释放量,以期了解病人的应激状况,同时测血糖(BS)和用放射免疫法测血胰岛素(SI)。结果表明烧伤后CA类释放是持续性的,且有休克和感染两个高峰(P<0.05,P<0.01);CA类释放主要是去甲肾上腺素(NE)的持续性增加,是正常量的两倍以上。休克期CA类释放如不增加,脓毒症阶段肾上腺素(E)与去甲肾上腺素从高值骤然下降,且低于休克期。提示:交感-肾上腺系统已处于衰竭状态,死亡似不可避免,而胰岛素分泌正常或相对不足。因此我们认为,CA类释放增加、糖原异生、胰岛β细胞分泌受抑制,是烧伤后全过程内分泌变化的主要原因。扩容纠酸、早期切痂预防感染以及使用抗CA类药物是防治的主要措施。 相似文献
3.
Zubin Bhagwagar Andrew J Montgomery Paul M Grasby Philip J Cowen 《Neuropsychopharmacology》2003,54(9):890-895
BACKGROUND: Elevated cortisol levels might account for the reduction in central serotonin 1A (5-hydroxytryptamine [5-HT](1A)) receptor binding and function observed in patients with major depression. We tested this hypothesis by studying the effect of acute administration of hydrocortisone on 5-HT(1A) receptor binding potential (BP) in subjects recovered from depression. METHODS: We studied 14 subjects (8 male, 6 female) who had recovered from at least two episodes of major depression and had been euthymic and drug free for at least 6 months. Serotonin 1A receptor BP was measured by [(11)C]WAY-100635 in conjunction with positron emission tomography. Subjects were tested on two occasions in a double-blind, random-order, crossover design after administration of either hydrocortisone (100 mg orally) or placebo 12 hours previously. Positron emission tomography scans were analyzed with a region of interest analysis. RESULTS: Hydrocortisone treatment did not decrease 5-HT(1A) receptor BP either in the hippocampus, which was our a priori hypothesis, or in other cortical 5-HT(1A) regions; however, female subjects had a higher 5-HT(1A) receptor BP in certain brain areas compared with male subjects. CONCLUSIONS: These data are consistent with an earlier study in healthy volunteers and do not support the proposal that decreased 5-HT(1A) receptor BP in patients with acute major depression is a consequence of cortisol hypersecretion. 相似文献
4.
The ascidian tadpole larva represents the basic body plan of all chordates in a relatively small number of cells and tissue types. Although it had been considered that ascidians develop largely in a determinative way, whereas vertebrates develop in an inductive way, recent studies at the molecular and cellular levels have uncovered several similarities in the way developmental fates are specified. In this review, we describe ascidian embryogenesis and its cell lineages, introduce several characteristics of ascidian embryos, describe recent advances in understanding of the mechanisms of cell fate specification, and discuss them in the context of what is known in vertebrates and other organisms. Developmental Dynamics 236:1748–1757, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
5.
Catalina Betancur Carmen Sandi Sergio Vitiello Jos Borrell Carmen Guaza Pierre J. Neveu 《Brain research》1992,589(2):302-306
Asymmetry in brain modulation of the immune system has been previously described. In mice, paw preference has been shown to be associated with immune reactivity but the mechanisms involved in such an association are not yet known. The autonomic nervous system and the neuroendocrine system are considered as major candidates for neural influences on the immune system. In the present study, the activity of the hypothalamic-pituitary-adrenal (HPA) axis of adult female mice selected for paw preference (left-handers vs. right-handers) was assessed by measuring both adrenocorticotropic hormone (ACTH) and corticosterone plasma levels, as well as the in vitro responses of hypothalamus and adrenocortical cells to various hormone releasing stimuli. The results reported here showed no difference in the activity of the HPA axis between left- and right-handed mice, suggesting that this neuroendocrine axis is not implicated in the association between functional brain asymmetry and immune reactivity. However, our results do not exclude the possibility that the HPA axis could play a role in such an association under other circumstances, such as during development or stressful situations. 相似文献
6.
彩色多普勒超声对高度近视眼后巩膜改变相关因素的评价 总被引:2,自引:0,他引:2
目的:探讨高度近视眼后巩膜形态改变与眼轴长度、近视程度及血流动力学变化之间的关系。方法:应用ATL超9型APOOGE-800型彩色多普勒超声诊断仪,探头频率5.0~10.0MHz。对26例正常眼,36例轻中度近视眼,51例高度近视眼后巩膜进行观察。并对26例正常眼,17例轻中度近视眼,26例高度近视眼的眼动脉(OA)、视网膜中央动脉(CRA)、睫状后动脉(PCA)进行检测。结果:轻中度近视组、高度近视组的眼轴长度与近视程度呈正相关性。两者之间的直线回归方程Y=-3510.3 1668.1X,R=0.9432,P<0.0001。后巩膜形态改变与正常对照组比较差异有显著性意义(P<0.001)。高度近视眼组、轻中度近视组与正常对照组比较,OA血流参数差异无显著性意义(P>0.05),而高度近视组的CRA、PCA的收缩期(PSV)、舒张期(EDV)、平均血流速度(AV)均减低,CRA的阻力指数(RI)升高(P<0.05)。轻中度组与对照组比较差异无显著性意义(P>0.05)。结论:视网膜血管、睫状血管系统血供不足与后巩膜形态变化的类型、眼轴长度、近视的程度及血流动力学改变密切相关,是引起高度近视眼病理性眼底改变发生和发展的重要因素。 相似文献
7.
3D kinematic analysis of the acromioclavicular joint during arm abduction using vertically open MRI.
Wataru Sahara Kazuomi Sugamoto Masakazu Murai Hiroyuki Tanaka Hideki Yoshikawa 《Journal of orthopaedic research》2006,24(9):1823-1831
Many researchers have evaluated the motions of the shoulder girdle, especially scapular and humeral motion. However, few reports exist that describe motions of the acromioclavicular joint. The purpose of the present study was to analyze the 3D kinematics of the acromioclavicular joint during arm abduction using 3D MR images obtained by a vertically open MRI. Fourteen shoulders of seven volunteers were examined in seven static positions from 0 degrees to the maximum abduction in a seated position. 3D surface models of the clavicle and scapula were created, and the movements of the acromioclavicular joint from 0 degrees to each position were calculated using the volume-based registration technique. From these calculations, the translations were evaluated and the rotational motions were analyzed using the concept of the screw axis. In the anteroposterior direction, the clavicle translated most posteriorly (-1.9 +/- 1.3 mm) at 90 degrees of abduction and most anteriorly (1.6 +/- 2.7 mm) at maximum abduction. In the superoinferior direction, the clavicle translated slightly superiorly (0.9 +/- 1.9 mm). When analyzing relative motion of the scapula with respect to the clavicle, the scapula generally rotated about a specific screw axis passing through the insertions of both the acromioclavicular and the coracoclavicular ligaments on the coracoid process. The average rotation was 34.9 +/- 8.4 degrees. 相似文献
8.
p. karling Å. danielsson r. adolfsson † & k.-f. Norrback † 《Neurogastroenterology and motility》2007,19(11):896-904
There is bidirectional comorbidity between anxiety/depression and irritable bowel syndrome (IBS). To investigate the prevalence of IBS symptoms, and factors associated with gastrointestinal symptoms in patients with recurrent depressive disorder. Patients (n = 95) with recurrent type of major depression according to DSM-IV criteria and sex- and age-matched controls (n = 190) were sent questionnaires investigating symptoms of IBS [Gastrointestinal Symptom Rating Scale (GSRS)-IBS] and symptoms of anxiety and depression [Hospital Anxiety and Depression Scale (HADS)]. Medical records were checked over a 10-year period for chronic somatic symptoms or diseases. Seventy-three patients with unipolar disorder (mean age 63.6 years SD 13.8; range 23-86 years) and 156 controls (mean age 59.2 years SD 11.6, range 21-85 years) responded. Patients with recurrent depression had higher GSRS-IBS scores and showed a strong correlation between symptoms of IBS and anxiety-depression (r(s) = 0.54; P < 0.001). IBS symptoms were also associated with multiple pain symptoms, higher health-seeking behaviour and selective-serotonin-reuptake inhibitor intake. However, patients with recurrent depression (n = 46) in remission (HADS-Depression score <8) did not have more symptoms of IBS than controls (GSRS-IBS median score 6.0 vs 6.5; P = 0.46). There is a strong association between symptoms of IBS and symptoms of anxiety and depression, whereas depressive patients in remission do not have more IBS symptoms than controls. 相似文献
9.
Arne Popma Robert Vermeiren Charlotte A M L Geluk Thomas Rinne Wim van den Brink Dirk L Knol Lucres M C Jansen Herman van Engeland Theo A H Doreleijers 《Neuropsychopharmacology》2007,61(3):405-411
BACKGROUND: In animals, strong evidence exists for an association between testosterone and aggression. In humans, and particularly in children and adolescents, findings have been less consistent. Previous research has suggested that this may partly be due to moderating effects of other factors, e.g., hormones. This study aims to investigate the moderating effect of cortisol on the relationship between testosterone and subtypes of aggression in delinquent male adolescents. METHODS: Participants were 103 boys (mean age 13.7) referred to a delinquency diversion program. Testosterone and cortisol levels were determined from saliva samples collected during resting conditions and related to self-report scores on overt and covert aggression. RESULTS: Linear regression analyses revealed a significant interaction between cortisol and testosterone in relation to overt aggression, with a significant positive relationship between testosterone and overt aggression in subjects with low cortisol levels but not in subjects with high cortisol levels. Using the same model for covert aggression, no significant effects of testosterone, cortisol, or testosterone x cortisol interaction were found. CONCLUSIONS: These results indicate a moderating effect of cortisol on the relationship between testosterone and overt aggression in delinquent male adolescents. Implications and directions for future research are discussed. 相似文献
10.
Belinda Garner Andrew M. Chanen Lisa Phillips Dennis Velakoulis Stephen J. Wood Henry J. Jackson Christos Pantelis Patrick D. McGorry 《Psychiatry Research: Neuroimaging》2007,156(3):257-261
This study used magnetic resonance imaging to examine pituitary gland volume (PGV) in teenage patients with a first presentation of borderline personality disorder (BPD). No difference in PGV was observed between healthy controls (n = 20) and the total BPD cohort (n = 20). However, within the BPD cohort, those exposed to childhood trauma (n = 9) tended to have smaller pituitaries (− 18%) than those with no history of childhood trauma (n = 10). These preliminary findings suggest that exposure to childhood trauma, rather than BPD, per se, might be associated with reduced PGV, possibly reflecting hypothalamic–pituitary–adrenal axis dysfunction. 相似文献