全文获取类型
收费全文 | 2412篇 |
免费 | 234篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 76篇 |
妇产科学 | 61篇 |
基础医学 | 297篇 |
口腔科学 | 76篇 |
临床医学 | 334篇 |
内科学 | 510篇 |
皮肤病学 | 26篇 |
神经病学 | 182篇 |
特种医学 | 287篇 |
外科学 | 247篇 |
综合类 | 83篇 |
预防医学 | 148篇 |
眼科学 | 51篇 |
药学 | 148篇 |
中国医学 | 3篇 |
肿瘤学 | 107篇 |
出版年
2021年 | 24篇 |
2019年 | 22篇 |
2018年 | 36篇 |
2017年 | 26篇 |
2016年 | 22篇 |
2015年 | 35篇 |
2014年 | 41篇 |
2013年 | 47篇 |
2012年 | 97篇 |
2011年 | 65篇 |
2010年 | 63篇 |
2009年 | 49篇 |
2008年 | 78篇 |
2007年 | 68篇 |
2006年 | 65篇 |
2005年 | 81篇 |
2004年 | 75篇 |
2003年 | 50篇 |
2002年 | 62篇 |
2001年 | 65篇 |
2000年 | 69篇 |
1999年 | 65篇 |
1998年 | 64篇 |
1997年 | 80篇 |
1996年 | 68篇 |
1995年 | 67篇 |
1994年 | 59篇 |
1993年 | 45篇 |
1992年 | 67篇 |
1991年 | 53篇 |
1990年 | 54篇 |
1989年 | 54篇 |
1988年 | 64篇 |
1987年 | 50篇 |
1986年 | 58篇 |
1985年 | 52篇 |
1984年 | 35篇 |
1983年 | 34篇 |
1982年 | 36篇 |
1981年 | 31篇 |
1978年 | 23篇 |
1977年 | 33篇 |
1976年 | 31篇 |
1974年 | 33篇 |
1973年 | 21篇 |
1972年 | 36篇 |
1971年 | 29篇 |
1970年 | 36篇 |
1969年 | 30篇 |
1966年 | 27篇 |
排序方式: 共有2653条查询结果,搜索用时 355 毫秒
51.
52.
Janine Jewanraj Sinaye Ngcapu Farzana Osman Veron Ramsuran Maryam Fish Andile Mtshali Ravesh Singh Leila E Mansoor Salim S Abdool Karim Quarraisha Abdool Karim JoAnn S Passmore Lenine J P Liebenberg 《Journal of the International AIDS Society》2021,24(6)
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women. 相似文献
53.
E E Levitt E L Baker R C Fish 《The American journal of clinical hypnosis》1990,32(4):225-36; discussion 237-49
Five experimental approaches to the resolution of the century-old Bernheim/Janet dispute and the issue of involuntariness or coercion (the classical suggestion effect) are presented. Four experiments are reported that follow one of the approaches: attempts to induce hypnotic subjects to resist suggestions made in trance. The design is one in which a "resistance instructor" proposes a reward for the resisting subject. Tentative inferences from the results are that the classical suggestion effect is found with a small number of subjects; for a larger number of subjects there is no classical suggestion effect, and for many subjects the outcome is equivocal. Relational factors in the hypnotic dyad influence responsiveness in the subject, the effect being least for those whose susceptibility is high. 相似文献
54.
55.
56.
Supratentorial cavernous haemangiomas and epilepsy: a review of the literature and case series 总被引:7,自引:0,他引:7 下载免费PDF全文
Moran NF Fish DR Kitchen N Shorvon S Kendall BE Stevens JM 《Journal of neurology, neurosurgery, and psychiatry》1999,66(5):561-568
OBJECTIVES: To characterise the clinical features and response to treatment of supratentorial cavernomas associated with epilepsy. METHODS: A systematic review of the literature was carried out and a retrospective case series of patients with cavernoma diagnosed by MRI and/or histology was compiled. Patient selection biases in the literature review were reduced as far as possible by selection of unbiased publications. RESULTS: In the literature, cavernomas were relatively less common in the frontal lobes. There were multiple cavernomas in 23% of cases. The main clinical manifestations were seizures (79%) and haemorrhage (16%). The annual haemorrhage rate was 0.7%. The outcome after excision was good with improvement in seizures in 92% of patients. In the case series the surgical outcome was less favourable, reflecting inclusion of a higher proportion of patients with intractable epilepsy. In both the literature review and the case series, outcome was poorer in cases with a longer duration of seizures at the time of surgery. CONCLUSIONS: The good surgical results, particularly in cases treated earlier, and the significant cumulative haemorrhage rate, suggest that excision is the optimum treatment. However, these factors have not been examined prospectively and, despite the availability of several retrospective studies, the optimum treatment, particularly for non-intractable cases, will only be determined by a prospective study. 相似文献
57.
Aggression heightened by alcohol or social instigation in mice: reduction by the 5-HT1B receptor agonist CP-94,253 总被引:1,自引:1,他引:0
Rationale: Models of heightened aggression may be particularly relevant in exploring pharmacological options for the clinical treatment
of aggressive and impulsive disorders. Objectives: To investigate and compare the effects of a 5-HT1B selective agonist, CP-94,253, on aggression that was heightened as a result of 1) social instigation or 2) alcohol treatment. Methods: Male CFW mice were administered 1.0 g/kg EtOH and were subsequently confronted by an intruder in their home cage. In a separate
experimental procedure, resident male mice were instigated to aggressive behavior by brief exposure to a provocative stimulus
male. To test the hypothesis that activation of the 5-HT1B receptor subtype would preferentially attenuate heightened aggression, in comparison to the moderate levels of species-typical
aggressive behaviors, the selective agonist, CP-94,253 (1.0–30 mg/kg, IP), and antagonists to the 5-HT1B (GR 127935; 10 mg/kg, IP) and the 5-HT1A receptor (WAY 100,635; 0.1 mg/kg IP) were used. Results: CP-94,253 suppressed non-heightened aggressive behavior (ED50=7.2 mg/kg ). GR 127935, but not WAY 100,635 shifted the ED50 for CP-94,253 to 14.5 mg/kg. Importantly, the anti-aggressive effects of CP-94,253 were not accompanied by locomotor sedation.
Alcohol-heightened and instigation-heightened aggression were suppressed at lower doses than those necessary to suppress non-heightened
aggression (ED50=3.8 and 2.7 mg/kg, respectively). Conclusions: The current results support the hypothesis that activation of 5-HT1B receptors modulates very high levels of aggressive behavior in a pharmacologically and behaviorally specific manner.
Received: 5 January 1999 / Final version: 16 April 1999 相似文献
58.
B Fish 《Archives of general psychiatry》1977,34(11):1297-1313
In chronic schizophrenics, disordered motor development in childhood is followed by more early cognitive and social impairment and poorer outcome; childhood schizophrenics represent the most extreme variants of this. Preschizophrenic infants show a fluctuating dysregulation of maturation--or "pandevelopmental retardation" (PDR)--that involves physical growth; gross motor, visual-motor, and cognitive development; proprioceptive and vestibular responses; muscle tone; and possibly arousal. Pandevelopmental retardation was significantly related to a genetic history for schizophrenia (less than .05), but not to obstetric complications. The severity of PDR was significantly related to the severity of later psychiatric and cognitive disorder (less than .01). Pandevelopmental retardation provides a "marker" in infancy for the inherited neurointegrative defect in schizophrenia. These disordered functions should be studied by anyone interested in the biology of the schizophrenic genotype or in specific early interventions for children at risk. 相似文献
59.
R Spencer W L Hutton W B Snyder D G Fuller G E Fish A Vaiser B F Jost 《Ophthalmic surgery》1992,23(11):766-769
In an effort to minimize surgical and visual morbidity of cryotherapy for retinopathy of prematurity (ROP), 18 eyes of 13 patients with 3 to 7 clock hours of stage 3 ROP with "plus" disease were treated by cryotherapy applications limited to the avascular retina adjacent to the areas of stage 3 disease. In 17 of 18 eyes, this limited use of cryotherapy was sufficient to cause regression of ROP without further treatments. After at least 3 months follow-up, ROP outcome showed a normal macular appearance in 16 eyes; two eyes developed macular dragging; no retinal detachments occurred. 相似文献
60.
D R Fish D Sawyers P J Allen J D Blackie A J Lees C D Marsden 《Archives of neurology》1991,48(2):210-214
The effect of sleep on the involuntary movements or dyskinesias in Parkinson's disease, Huntington's disease, primary and secondary torsion dystonia, and Gilles de la Tourette syndrome was studied in a total of 52 patients and 10 normal subjects using video electroencephalographic telemetry. Movements typical of the wake pattern were seen occasionally during unequivocal sleep in all but two completed studies, and in each condition reappeared under similar circumstances. The movements were most likely to occur after awakenings or lightenings of sleep, or in stage one sleep. The movements were very rare during the deeper phases of sleep. Those movements that occurred during sleep without awakenings were usually preceded by arousal phenomena and, rarely, by sleep spindles or slow waves. The control group showed normal "semipurposeful" movements under the same conditions during sleep. The rare appearance of the different dyskinesias and normal movements under similar circumstances during sleep could be a result of common effects on the generator systems or changes in the excitability of the final common motor pathway. 相似文献