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61.
H. Schneider J. Sperner J. U. Dröszus H. Schachinger 《Virchows Archiv : an international journal of pathology》1976,372(3):183-194
Summary The ultrastructure of neuroglial fatty metamorphosis (GFM) has been investigated in the telencephalic white matter of 12 premature and mature infants (gestational age 22–40 weeks; survival 0–96 days). GFM was found in all cases apart from a 22-week-old fetus, and involves predominantly astrocytic cells (68.8%), then glioblasts (43.5%), but only 7.4% of oligodendrocytes. GFM, therefore, seems to be independent of the myelination process and indicates the vulnerability of the immature neuroglial population in the metabolic and circulatory disorders of the perinatal period. Since GFM is found in almost all children dying within the early postnatal period, this subtle alteration reflects a special form of minimal brain damage. The relationship between GFM, astrocytic hypertrophy and periventricular leucomalacia and their role in the telencephalic leucoencephalopathy are discussed.
Zusammenfassung Die Gliazellverfettung im unreifen Großhirn-Marklager wurde bei 12 Kindern ultrastrukturell untersucht (Gestationsalter 22–40 Wochen; Überlebenszeit 0–96 Tage). Die fettige Metamorphose der Neuroglia (Virchow) fand sich in allen Fällen, ausgenommen den 22 Wochen alten Feten, und betrifft vorwiegend junge Astrozyten (68,8%), ferner zu 43,5% unreife Vorstufen, jedoch nur zu 7.4% die (z.Z. der Geburt erst in Erscheinung tretende) Oligodendroglia. Die Fett-Metamorphose der unreifen Glia stellt einen sensiblen Indikator für metabolisch-zirkulatorische Störungen der Perinatalperiode dar und erfolgt unabhängig von dem Prozeß der Markscheidenbildung. Zusammen mit einer oft auffälligen Astroglia-Proliferation ist die intracytoplasmatische Akkumulation nicht membrangebundener Lipide Ausdruck einer temporären Differenzierungsstörung der unreifen Neuroglia. Die resultierende Reifungsdissoziation mit Unterdrückung der oligodendrozytären Zellinie führt zur retardierten Markscheidenbildung und dem Bild der telencephalen Leucoencephalopathie.相似文献
62.
Publication Guidelines for Heart Rate Studies in Man 总被引:1,自引:0,他引:1
J. Richard Jennings W. Keith Bberg J. Stanford Hutcheson Paul Obrist Stephen Porges Graham Turpin 《Psychophysiology》1981,18(3):226-231
Publication guidelines are provided for the collection, quantification, and analysis of heart rate data. 相似文献
63.
Description of Heart-Rate Variability Data in Accordance With a Physiological Model for the Genesis of Heartbeats 总被引:2,自引:0,他引:2
A survey is presented of techniques which transform heart-rate variability data into a signal that is both visually informative and accessible for analysis. The Instantaneous Heart-Rate (IHR) signal is introduced, i.e. the signal having the value of the heart rate (inverse interbeat interval) during the interval concerned. The IHR signal differs from the standard Delayed Heart-Rate (DHR) signal, which is always one beat late. The relationship is discussed between the different representation methods and the Integral Pulse Frequency Modulation (IPFM) model, the latter being a physiologically plausible model for the transformation of a continuous input signal (e.g., nervous influence on the cardiac pacemaker) into a series of events (heartbeats). It is shown that when the IHR signal is used as input of the IPFM model, the event series from which the signal was derived appears at the output. Hence, if the IPFM model is accepted as a model of the pacemaker, the IHR signal may be considered as an approximation of the neural (sympathetic and parasympathetic) influence on the pacemaker. In addition we show that the appearance of the IHR signal is less affected by trigger errors or extrasystoles than the standard DHR signal. It is concluded that the most attractive time-domain representation of physiological event series consists of the IHR signal, because this signal, being conceptually and computationally simple, is consistent with the IPFM model. 相似文献
64.
Previous studies demonstrated distinct cardiovascular patterns associated with threat and challenge appraisals for groups of participants. We extend these results by assessing whether appraisals continue to be associated with these cardiovascular response patterns within an individual as appraisals change. Participants completed four verbal mental arithmetic tasks for which they made appraisals before and after each task. Cardiac reactivity and total peripheral resistance (TPR) were calculated for the first and last minutes of each task, and the number of responses and percent correct were measured for each task. In line with our prediction, pretask appraisals were related to some task-related cardiac responses across the four tasks. In addition, task-related cardiovascular reactivity and behaviors both influenced appraisals following the task. Our findings suggest that an idiographic analysis of appraisals, cardiovascular physiology, and task-related behaviors provides a richer understanding of the appraisal process and reveals sex differences deserving further assessment. 相似文献
65.
Peter A. Shapiro Richard P. Sloan Emilia Bagiella J. Thomas Bigger JR. Jack M. Gorman 《Psychophysiology》1996,33(1):54-62
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation. 相似文献
66.
Carretti N Florio P Bertolin A Costa CV Allegri G Zilli G 《Human reproduction (Oxford, England)》2005,20(6):1548-1553
BACKGROUND: Serotoninergic (5-HT) neurons are suggested to regulate estrous cycle in animal models. In the present study we evaluated whether a relationship exists between the serotoninergic precursors in the central nervous system and the gonadotrophin-ovarian cyclic function. METHODS: We measured 5-HT precursors [free (FT) and total (TT) tryptophan] and LH, FSH and 17beta-estradiol (E2) levels in the serum of 15 fertile women with normal menstrual cycles during the follicular (cycle days 1-5, 7-11), mid-cycle (cycle days 14-16) and luteal (cycle days 17-19, 22-24) phases. RESULTS: TT and FT were significantly increased in the 7-11 and 17-19 cycle days and were decreased at mid-cycle (P < 0.01), with a cyclic and opposite behaviour when compared to that of FSH and LH. Indeed, correlation analysis through the matrix of mean values showed that LH was negatively correlated to TT (r = -0.636) and FT (r = -0.574), as well as FSH (TT, r = -0.655; FT, r = -0.663), and that TT and FT were positively correlated to each other (r = 0.801; P < 0.001). Furthermore, whilst the two FT peaks reached approximately the same levels in the follicular and luteal phase, TT levels were approximately 30% higher in the luteal than in the follicular phase of the cycle: thus in the first (follicular) phase FT peak was relatively higher than that of TT, whereas the contrary occurred in the second (luteal) phase of the cycle. CONCLUSIONS: Both TT and FT levels have cyclic variations throughout the menstrual cycle, being lowest at mid-cycle (14-16 cycle days), concomitant with the highest LH and FSH concentrations, and higher before and after mid-cycle phase, coinciding with the lowest circulating LH/FSH levels. Since TT and FT levels in the plasma have cyclic changes, our study: (i) suggests that a consumption of serum serotonin precursors takes place concomitant with gonadotrophin release during menstrual cycle; (ii) may represent an in vivo model to investigate this relationship in women in different physiopathological conditions. 相似文献
67.
背景:近年来,随着全膝关节置换技术提升、手术时间缩短、术中及术后止血药的应用,其总失血量不断减少,术后引流量也逐渐减少,术后快速康复理论应运而生,引流管放置也再次成为骨科医生所热议的问题,越来越多的医生认为可以常规取消放置引流,引流似乎已可有可无。目的:旨在复习既往文献,对全膝关节置换后引流放置的相关问题归纳总结,提供围术期引流管理的相关经验。方法:检索中国知网、万方、维普、中国生物医学文献数据库等中文数据库,以及PubMed、The Cochrane Library、WebofScience、EMBASE、OVID等外文数据库,以"引流,膝关节置换术"及"totalknee arthroplasty,drainage"为检索词,检索自建库始至2020年2月为止所有与主题相关的文献,总结归纳全膝关节置换后不放置引流管围术期各方面需综合考虑的要素。结果与结论:①引流管的放置问题关乎全膝关节置换手术的最终结果,与术后出血、血肿、血栓、感染等并发症的发生关系密切;②目前全膝关节置换术后不推荐常规放置引流,但不意味着不需要管理,其实际上对临床医护在围术期各方面的管理提出更高的要求,包括但不限于术前适应证选择、手术操作、止血带使用、术中及术后药物使用、物理疗法的使用等。 相似文献
68.
69.
张丽 《国际中华应用心理学杂志》2006,3(2):97-99
目的探讨住院精神分裂症患者恢复期的心理卫生状况及心理护理干预效果。方法将76例处于恢复期的住院精神分裂症患者随机分为两组,封其中的38例追行心理谩理干预(干预组),并与对照组(未干预组)退行比较。采用SCL-90(症状自评量表)于干预前和干预后4周末造行量表抨定。枯果住院精神分裂症患者恢复期的主要心理闪题为抑郁、焦虑、人际关系、强迫、敌对、偏执等。干预组在干预后4周末SLC-90的焦虑、抑郁、人际关系3个因子分与干预前相比有非常显着性差异(P〈0.01)。强迫、敌对、偏执3个因子分有显着性差异(P〈0.05)。其他各项因子分差异无显着性(P〉0.05);而对照组各因子分干预前后相比无显着性差异(P〉0.05)。干预后两组在SCL-90的焦虑、抑郁、人际关系、强迫、敌对、偏执等6个因子分比较有显着性差异(P〈0.05)。结论心理护理干预能明显改善住院精神分裂症患者恢复期的心理卫生状况,促进病人的康复。 相似文献
70.
There are a number of reports suggesting an association between profusion of eye movements and active dreaming. It has however been suggested that this relationship might only be evident in comparisons across the night and would not be evident in comparisons within one REM period. Data from 20 subjects taking placebo, amylobarbitone, and nitrazepam were used to test this. Dream reports were collected from REM awakenings and rated blind as visually active or passive. Eye movement profusion (number of 2 sec epochs) was assessed for each REM period. Correlation between dream content and eye movement was low but significant in comparisons including the whole night, and including data from drug, withdrawal, and placebo conditions. A significant correlation was not consistently obtained, however, when data from each REMP were considered separately. Correlations based on data from non-drug nights only were also small and could have been due to chance effects alone. The low correlations were not explicable solely by poor reliability of content ratings. It is concluded that the relationship between visually active dreaming and eye movement is slight, and may not hold when time of night is adequately controlled. 相似文献