全文获取类型
收费全文 | 24669篇 |
免费 | 2363篇 |
国内免费 | 419篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 521篇 |
妇产科学 | 500篇 |
基础医学 | 2305篇 |
口腔科学 | 123篇 |
临床医学 | 3579篇 |
内科学 | 1859篇 |
皮肤病学 | 109篇 |
神经病学 | 8650篇 |
特种医学 | 177篇 |
外科学 | 907篇 |
综合类 | 2525篇 |
现状与发展 | 2篇 |
一般理论 | 4篇 |
预防医学 | 1717篇 |
眼科学 | 60篇 |
药学 | 2153篇 |
30篇 | |
中国医学 | 1491篇 |
肿瘤学 | 668篇 |
出版年
2024年 | 131篇 |
2023年 | 520篇 |
2022年 | 709篇 |
2021年 | 1092篇 |
2020年 | 1152篇 |
2019年 | 1067篇 |
2018年 | 1032篇 |
2017年 | 1115篇 |
2016年 | 1149篇 |
2015年 | 1005篇 |
2014年 | 1533篇 |
2013年 | 2269篇 |
2012年 | 1392篇 |
2011年 | 1410篇 |
2010年 | 1256篇 |
2009年 | 1196篇 |
2008年 | 1172篇 |
2007年 | 1138篇 |
2006年 | 995篇 |
2005年 | 843篇 |
2004年 | 670篇 |
2003年 | 634篇 |
2002年 | 546篇 |
2001年 | 421篇 |
2000年 | 296篇 |
1999年 | 223篇 |
1998年 | 231篇 |
1997年 | 257篇 |
1996年 | 174篇 |
1995年 | 163篇 |
1994年 | 171篇 |
1993年 | 131篇 |
1992年 | 148篇 |
1991年 | 119篇 |
1990年 | 101篇 |
1989年 | 118篇 |
1988年 | 107篇 |
1987年 | 116篇 |
1986年 | 93篇 |
1985年 | 115篇 |
1984年 | 83篇 |
1983年 | 62篇 |
1982年 | 64篇 |
1981年 | 50篇 |
1980年 | 43篇 |
1979年 | 32篇 |
1978年 | 22篇 |
1977年 | 25篇 |
1976年 | 18篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
帕罗西汀合用心理行为干预治疗老年期抑郁症的疗效 总被引:1,自引:0,他引:1
闫加民 《中国健康心理学杂志》2008,16(8):926-927
目的探讨帕罗西汀合用心理行为治疗对老年期抑郁症的疗效。方法将60例老年期抑郁症随机分成两组,进行为期6周的对照研究,出院后随访1年,分别用心理行为合并帕罗汀治疗(研究组)和帕罗西汀治疗(对照组);采用汉密尔顿抑郁量表(HAMD)和临床疗效总评量表(CGI—SI)进行评定。结果研究组在治疗6周后HAMD评分(9.32±2.28)较对照组(13.17±3.39)有显著性差异(P〈0.01),研究组CGI—SI较对照组有显著性差异(P〈0.01),1年末随访时HAMD评分研究组(9.19±2.33)较对照组(13.98±4.96)有显著性差异(P〈0.01)。且研究组复发率低于对照组(P〈0.05)。结论帕罗西汀合用心理行为治疗对老年期抑郁症的疗效优于帕罗西汀,且复发率低。 相似文献
82.
S. P. Perrett 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(2):115-124
Little is known about mechanisms used by the nervous system to encode time. In light of recent evidence, cerebellar cortex
involvement in the learned timing of conditioned eyelid responses shows promise as an area of investigation into neural timing
mechanisms. Lesion studies indicate that the cerebellar cortex is necessary for response timing, but do not rule out the possibility
that response timing is encoded afferent to the cerebellum. To differentiate between precerebellar and cerebellar cortical
timing mechanisms, rabbits were trained by pairing direct stimulation of mossy fibers in the cerebellum as the conditioned
stimulus (CS) with an eyeshock unconditioned stimulus (US). We find that individual animals can produce diffently timed conditioned
responses when trained with a mossy fiber CS that has been paired with the US at various interstimulus intervals. The fact
that differently timed responses can be conditioned using constant-frequency stimulation of an invariant subset of mossy fibers
as the CS suggests that timing information in the afferent input to the cerebellum is not essential. Two rabbits trained with
single-pulse stimulation in the cerebellum as the CS also learned differently timed conditioned responses; suggesting that
fiber recruitment during a stimulus train does not convey the necessary temporal coding to the cerebellar cortex. Together
with the lesion data, these findings suggest that the learned timing of conditioned eyelid responses occurs in the cerebellar
cortex.
Received: 25 August 1997 / Accepted: 12 January 1998 相似文献
83.
J. M. SMITH M. F. JAMES K. H. J. BOCKHORST M. I. SMITH D. P. BRADLEY N. G. PAPADAKIS T. A. CARPENTER A. A. PARSONS R. A. LESLIE L. D. HALL C. L.‐H. HUANG 《Journal of anatomy》2001,198(5):537-554
Cortical spreading depression (CSD) and peri‐infarct depolarisation (PID) are related phenomena that have been associated with the human clinical syndromes of migraine (CSD), head injury and stroke (PID). Nevertheless the existence of CSD in man remains controversial, despite the detection of this phenomenon in the brains of most, if not all, other animal species investigated. This failure to unambiguously detect CSD clinically may be at least partly due to the anatomically complex, gyrencephalic structure of the human brain. This study was designed to establish conditions for the study of CSD in the brain of a gyrencephalic species using the noninvasive technique of magnetic resonance imaging (MRI). The 3‐dimensional (3D) gyrencephalic anatomy of the cat brain was examined to determine the imaging conditions necessary to detect CSD events. Orthogonal transverse, sagittal and horizontal T1‐weighted image slices showed that the marginal and suprasylvian gyri were the most appropriate cortical structures to study CSD. This was in view of (1) their simple geometry: (2) their lengthy extent of grey matter orientated rostrocaudally in the cortex: (3) their separation by a sulcus across which CSD spread could be studied and (4) the discontinuity in the grey matter in these regions between the right and left hemispheres dorsal to the corpus callosum. The structure suggested by the T1‐weighted images was corroborated by systematic diffusion tensor imaging to map the fractional anisotropy and diffusion trace. Thus a single horizontal image plane could visualise the neighbouring suprasylvian and marginal gyri of both cerebral hemispheres, whereas its complex shape and position ruled out the ectosylvian gyrus for CSD studies. With the horizontal imaging plane, CSD events were reproducibly detected by animating successive diffusion‐weighted MR images following local KCl stimulation of the cortical surface. In single image frames, CSD detection and characterisation required image subtraction or statistical mapping methods that, nevertheless, yielded concordant results. In repeat experiments, CSD events were qualitatively similar in appearance whether elicited by sustained or transient KCl applications. Our experimental approach thus successfully describes cat brain anatomy in vivo, and elucidates the necessary conditions for the application of MRI methods to detect CSD propagation. 相似文献
84.
Simon Gilbody David Richards Michael Barkham 《The British journal of general practice》2007,57(541):650-652
There is increased emphasis on routine assessment of depression in primary care. This report is the first UK validation of two self-completed measures: the Patient Health Questionnaire (PHQ-9) and the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM). Optimum cut-off points were established against a diagnostic gold standard in 93 patients. PHQ-9 sensitivity = 91.7% (95% confidence interval [CI] = 77.5 to 98.3%) and specificity 78.3% (95% CI = 65.8 to 87.9%). CORE-OM sensitivity = 91.7% (95% CI = 77.5 to 98.2%) and specificity = 76.7% (95% CI = 64.0 to 86.6%). Brief self-rated questionnaires are as good as clinician-administered instruments in detecting depression in UK primary care. 相似文献
85.
M. M. Cohen B. Schei D. Ansara R. Gallop N. Stuckless D. E. Stewart 《Archives of women's mental health》2002,4(3):83-92
Summary
Background: A link between violence and depression has been shown, but not a link between violence and postpartum depression. This study
sought to determine if there is an association between a history of abuse (physical, sexual, emotional as a child or adult)
and postpartum depression (PPD).
Method: 200 postpartum women were recruited from 6 hospitals. At 8–10 weeks postpartum, a telephone interviewer asked women about
physical, emotional or sexual abuse as an adult or child and sociodemographic, obstetrical and personal medical history. PPD
was assessed using the Edinburgh Postnatal Depression Scale (EPDS, score of ≥12). Abuse was determined by the Conflict Tactics
Scale or the Abuse Assessment Screen. Chi-square and logistic regression were used to determine the relationship between violence
and PPD.
Results: 11% of women had EPDS scores of ≥12. Rates of childhood (6.5%), or adult (6.5%) physical abuse; and childhood (13%) or adult
(14%) sexual abuse were reported by respondents. Emotional abuse in the current relationship (29.6%) exceeded that of childhood
abuse (3.5%). Overall 43.2% of respondents had at least one form of abuse. Having a history of depression (OR = 3.3 (95% CI,
1.3–8.7)), panic attack during pregnancy (OR = 5.4 (1.6–19.0)), maternal complications (OR = 5.0 (1.7–15.1)), low social support
(OR = 3.3 (1.3–8.7)) and emotional abuse (OR = 2.8 (1.1–7.4) were associated with PPD.
Conclusion: Emotional abuse but not physical or sexual abuse was found to be associated with PPD. A possible explanation for this relationship
may be that being in an abusive situation puts one at risk for depression and in turn, postpartum depression. 相似文献
86.
We calculated a Research Diagnostic Criteria (RDC) endogenous score for 257 depressed inpatients based on the number of endogenous criteria present. The distribution of RDC endogenous scores was unimodal. There was no association between endogenous scores and results of the Dexamethasone Suppression Test, or morbid risk for depression in the patients' first-degree relatives. The morbid risk for a family history of alcoholism tended to decrease with increasing endogenous scores, although a consistent steady decline was not observed. The results suggest that the RDC criteria do not fit either the categorical or dimensional model of endogenous classification. Potential sources of difficulty with the RDC endogenous criteria are discussed. 相似文献
87.
Background: Posttraumatic stress disorder (PTSD) is common in refugees but its association with longer-term psychosocial dysfunction remains unclear. We examined whether a subgroup of refugees with comorbid PTSD and depression were at particularly high risk of disability. We also investigated whether specific trauma experiences were linked to this comorbid pattern. Methods: Consecutive Bosnians (and one or two compatriots nominated by them) were recruited from a community centre, yielding a total sample of 126 participants (response rate 86%). Measures included a trauma inventory, the Clinician Administered PTSD Scale (CAPS) (Blake et al., 1995) and the depression module of the Structured Clinical Interview (SCID) (First et al., 1997). Results: Three diagnostic groupings emerged: normals (n=39), pure PTSD (n=29), and comorbid PTSD and depression (n=58). Of four trauma dimensions derived from principle components analysis (human rights violations, dispossession and eviction, life threat and traumatic loss), life threat alone was associated with pure PTSD, with life threat and traumatic loss both being associated with comorbidity. Compared to normals and those with pure PTSD, the comorbid group manifested more severe PTSD symptoms as well as higher levels of disability on all indices (global dysfunction: odds RATIO=5.0, P<0.001, distress: odds RATIO=6.0, P<0.001, social impairment: odds ratio 5.9, P<0.001, and occupational disability: odds ratio 5.0, P<0.001). Limitations: Recruitment was not random, the sample size was modest, and trauma event endorsement was based on retrospective accounts. Conclusions: The combination of life threat and traumatic loss may be particularly undermining to the psychological well-being of refugees and consequent comorbidity of PTSD and depression may be associated with longer-term psychosocial dysfunction. The findings raise the question whether the comorbid pattern identified should be given more recognition as a core posttraumatic affective disorder. 相似文献
88.
Carolyn A Chew-Graham Karina Lovell Chris Roberts Robert Baldwin Michael Morley Alistair Burns David Richards Heather Burroughs 《The British journal of general practice》2007,57(538):364-370
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients. 相似文献
89.
Rubem Carlos Araujo Guedes Romualdo José do Carmo 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(3):341-349
Summary The ionic composition of the internal environment was altered in rabbits by means of gastric washing, combined with intramuscular administration of 3-Beta-aminoethylpyrazole. The effects of this treatment on cortical spreading depression (SD) were studied. C1- and Na+ concentrations decreased significantly in serum and in cerebrospinal fluid after the treatment. This made the animals much more susceptible to SD, as established by the high incidence of spontaneous SD, increased SD velocity of propagation and facilitated its interhemispheric transfer. An intensification of the epileptiform activity associated with SD was also observed. Intravenous replacement of NaCl abolished the above effects on SD. When the intravenous replacement was done with Na-Isethionate, those effects were enhanced. It is concluded that chloride deficiency was the main factor responsible for the observed facilitating effects.This work was supported by grants from the BNDE (FUNTEC-74 e 143), CNPq and CAPES 相似文献
90.
J. M. Rothfeld J. F. Hejtmancik P. M. Conn D. W. Pfaff 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,69(1):113-118
Summary The slow potential change (spc) accompanying spreading depression (SD) was studied in rats and in a seizure-sensitive strain of Mongolian gerbil under three different experimental paradigms, each involving the use of naloxone. Gerbils undergoing electroconvulsive shock treatment displayed SD during the post-ictal phase, which was blocked by the intraperitoneal (i.p.) administration of naloxone (20–50 mg kg-1). Topical application of naloxone to the exposed cortex of the anaesthetized gerbil and rat blocked the spc of SD evoked by KCl. Microiontophoretic ejection of naloxone during extracellular recordings reversed cell refractoriness following the spc, demonstrated by the observation of a maintained sensitivity to iontophoretic pulses of glutamate. The results suggest a possible involvement of naloxone-sensitive processes in the mechanism responsible for cortical SD. 相似文献