全文获取类型
收费全文 | 1322篇 |
免费 | 78篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 28篇 |
妇产科学 | 33篇 |
基础医学 | 137篇 |
口腔科学 | 21篇 |
临床医学 | 189篇 |
内科学 | 208篇 |
皮肤病学 | 17篇 |
神经病学 | 96篇 |
特种医学 | 91篇 |
外科学 | 219篇 |
综合类 | 26篇 |
一般理论 | 1篇 |
预防医学 | 81篇 |
眼科学 | 45篇 |
药学 | 135篇 |
中国医学 | 9篇 |
肿瘤学 | 54篇 |
出版年
2024年 | 2篇 |
2023年 | 17篇 |
2022年 | 34篇 |
2021年 | 53篇 |
2020年 | 42篇 |
2019年 | 66篇 |
2018年 | 64篇 |
2017年 | 48篇 |
2016年 | 50篇 |
2015年 | 45篇 |
2014年 | 58篇 |
2013年 | 94篇 |
2012年 | 91篇 |
2011年 | 107篇 |
2010年 | 72篇 |
2009年 | 72篇 |
2008年 | 75篇 |
2007年 | 46篇 |
2006年 | 47篇 |
2005年 | 41篇 |
2004年 | 44篇 |
2003年 | 39篇 |
2002年 | 38篇 |
2001年 | 26篇 |
2000年 | 18篇 |
1999年 | 7篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 8篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 8篇 |
1988年 | 12篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1979年 | 7篇 |
1978年 | 2篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有1405条查询结果,搜索用时 0 毫秒
71.
In this prospective pilot trial, B-flow ultrasonographic (US) imaging was compared with color duplex flow US in the evaluation of internal carotid arterial stenosis. Despite almost excellent interobserver variability, none of the investigated B-flow imaging parameters correlated with those of duplex US. In conclusion, the investigated B-flow imaging parameters cannot be used in evaluating internal carotid arterial stenosis. 相似文献
72.
Predictors of long-term results after treatment of iliac artery obliteration by transluminal angioplasty and stent deployment 总被引:7,自引:0,他引:7
Funovics MA Lackner B Cejna M Peloschek P Sailer J Philipp MO Maca T Ahmadi A Minar E Lammer J 《Cardiovascular and interventional radiology》2002,25(5):397-402
Purpose: To investigate initial and
long-term success rate after percutaneous treatment of iliac artery
occlusion with angioplasty and stent deployment. To investigate the
influence of vascular comorbidity, lesion length, stent placement and
lesion coverage as possible predictors of outcome.
Methods: Between January 1994 and December 1999, 80 iliac
recanalizations were performed on 78 patients, median age 61.1 ±
11.5 (SD) years. All patients were followed up by clinical
examinations, duplex ultrasound and intravenous digital subtraction
angiography. Mean follow-up time was 2.0 ± 1.53 (SD) years.
Multivariate Cox regression analysis was used to determine the
influence of cofactors on patency.
Results: One, 2 and 4
years after recanalization, primary patency was 78.1%, 74.5% and
64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively.
Patients with shorter occlusions, complete lesion coverage and patent
ipsilateral femoral arteries had significantly longer patency rates.
Complications included inguinal hematoma (n=1), technical
failure (n=3) aortic dissection (n=1), embolic
occlusions (n=7), gluteal claudication (n=1) and
genital necrosis after subsequent urethral surgery in one patient with
contralateral occlusion and ipsilateral overstenting of the internal
iliac artery with subsequent stenosis. Complications were of permanent
clinical significance in seven of 78 (9%) of the patients. In 17
(22%) cases, percutaneous reintervention was performed with
angioplasty in the stent (n=16) or deployment of a new stent
(n=1).
Conclusion: Endoluminal stent
placement has its place in an interdisciplinary therapeutic approach as
a viable therapeutic alternative to major transabdominal bypass surgery
and can be performed with comparable complication rates. Patients with
short occlusions, patent femoral arteries, and stents covering the
entire occlusion have significant longer patency. 相似文献
73.
Although no ionizing radiation is involved, patients undergoing magnetic resonance imaging (MRI) are exposed to powerful static magnetic fields, magnetic field gradients, and radio-frequency fields that may be potentially damaging. Our study aims to document the effect of MRI imaging sequences on early murine embryo development (two-cell to blastocyst stage) in vitro. Two-cell murine embryos were exposed to various lengths of MRI using pulse sequences employed in present day clinical imaging. Early murine embryo development was documented in vitro, and blastocyst development rates were computed for both the control and exposed groups. There were no significant differences detected in the rate of blastocyst formation between the control groups and the embryos exposed to MRI. 相似文献
74.
Yones Lotfi Tayebeh Ahmadi Abdollah Moossavi Enayatollah Bakhshi 《Auris, nasus, larynx》2019,46(1):64-69
Objective
Previous studies have shown that a subgroup of children with suspected (central) auditory processing disorder (SusCAPD) have insufficient ability to use binaural cues to benefit from spatial processing. Thus, they experience considerable listening difficulties in challenging auditory environments, such as classrooms. Some researchers have also indicated the probable role of binaural temporal fine structure (TFS) in the perceptual segregation of target signal from noise and hence in speech perception in noise. Therefore, in the present study, in order to further investigate the underlying reason for listening problems against background noise in this group of children, their performance was measured using binaural TFS sensitivity test (TFS-LF) as well as behavioral auditory lateralization in noise test, both of which are based on binaural temporal cues processing.Methods
Participants in this analytical study included 91 children with normal hearing and no listening problems and 41 children (9–12 years old) with SusCAPD who found it challenging to understand speech in noise. Initially, the ability to use binaural TFS was measured at three frequencies (250, 500 and 750 Hz) in both the groups, and the results of preliminary evaluations were compared between normal children and those with SusCAPD who participated in the study. Thereafter, the binaural performance of the 16 children with SusCAPD who had higher thresholds than the normal group at all three frequencies tested in TFS-LF test was examined using the lateralization test in 7 spatial locations.Results
Total 16 of the 41 children with SusCAPD who participated in this study (39%) showed poor performance on the TFS-LF test at all three frequencies, compared to both normal children and other children in the APD group (p < 0.05). Furthermore, children in the APD group with binaural TFS coding deficits at all three frequencies revealed significant differences in the lateralization test results compared to normal children (p < 0.05).Conclusion
Findings of the current study demonstrated that one of the underlying causes for the difficulty understanding speech in noisy environments experienced by a subgroup of children with SusCAPD can be the reduced ability to benefit from binaural TFS information. This study also showed that a reduced ability to use binaural TFS cues in the group of children with SusCAPD was accompanied by reduced binaural processing abilities in the lateralization test which also admit the presence of binaural temporal processing deficits in this group of children. 相似文献75.
76.
Lehrner J Willfort A Mlekusch I Guttmann G Minar E Ahmadi R Lalouschek W Deecke L Lang W 《Journal of clinical and experimental neuropsychology》2005,27(7):859-866
Percutaneous transluminal angioplasty with stenting (PTAS) has become a treatment option for severe carotid stenosis. The goal of our study was to determine prospectively neurocognitive outcome 6 months after unilateral stent-protected carotid angioplasty. Twenty consecutive patients who underwent stent-protected angioplasty for symptomatic (n=9) or asymptomatic (n=11) high-grade carotid stenosis were investigated and compared to an age and disease matched control group. Patients were administered preprocedurally and 6 months postprocedurally a battery of neuropsychological tests. We used reliable change indices methodology in order to control for practice and statistical effects unrelated to intervention. We found no cognitive change in approximately 90% of patients and cognitive improvement in approximately 10% of patients for concentration and attention variables. We further found no cognitive change in 61% of patients, cognitive improvement in 11% of patients and cognitive deterioration in 28% of patients for psychomotor speed. No cognitive change in 94% of patients and cognitive deterioration in 6% of patients was found for sustained attention; no cognitive change in 80% of patients, cognitive improvement in 15% of patients and cognitive deterioration in 5% of patients was found for verbal fluency; no cognitive change in 100% of patients was found for interference (Stroop test): no cognitive change in 95% of patients, cognitive improvement in 5% of patients was found for interference (c.I. test), respectively.Our study showed that 6 months after PTAS cognitive functioning did not change in most patients significantly. For some patients, however, significant improvement or deterioration in single neurocognitive domains can be expected. The reasons for these changes are unclear but may depend on variable type; magnitude of microemboli production; right vs. left cerebral vasculature, respectively. 相似文献
77.
78.
Zeilhofer HU Studler B Arabadzisz D Schweizer C Ahmadi S Layh B Bösl MR Fritschy JM 《The Journal of comparative neurology》2005,482(2):123-141
Although glycine is a major inhibitory transmitter in the mammalian CNS, the role of glycinergic neurons in defined neuronal circuits remains ill defined. This is due in part to difficulties in identifying these cells in living slice preparations for electrophysiological recordings and visualizing their axonal projections. To facilitate the morphological and functional analysis of glycinergic neurons, we generated bacterial artificial chromosome (BAC) transgenic mice, which specifically express enhanced green fluorescent protein (EGFP) under the control of the promotor of the glycine transporter (GlyT) 2 gene, which is a reliable marker for glycinergic neurons. Neurons expressing GlyT2-EGFP were intensely fluorescent, and their dendrites and axons could be visualized in great detail. Numerous positive neurons were detected in the spinal cord, brainstem, and cerebellum. The hypothalamus, intralaminar nuclei of the thalamus, and basal forebrain also received a dense GlyT2-EGFP innervation, whereas in the olfactory bulb, striatum, neocortex, hippocampus, and amygdala positive fibers were much less abundant. No GlyT2-EGFP-positive cell bodies were seen in the forebrain. On the subcellular level, GlyT2-EGFP fluorescence was colocalized extensively with glycine immunoreactivity in somata and dendrites and with both glycine and GlyT2 immunoreactivity in axon terminals, as shown by triple staining at all levels of the neuraxis, confirming the selective expression of the transgene in glycinergic neurons. In slice preparations of the spinal cord, no difference between the functional properties of EGFP-positive and negative neurons could be detected, confirming the utility of visually identifying glycinergic neurons to investigate their functional role in electrophysiological studies. 相似文献
79.
80.
Lessan-Pezeshki M Ghazizadeh S Khatami MR Mahdavi M Razeghi E Seifi S Ahmadi F Maziar S 《Transplantation proceedings》2004,36(5):1405-1406
PURPOSE: Our purpose was to investigate reproductive performance among kidney transplant recipients. MATERIALS AND METHODS: We studied 126 kidney transplanted women 15 to 68 years of age including 33 who were single and 93 who were married. RESULTS: Infertility was seen in 10.4% of those who desired pregnancy, a rate similar to the general population. The most common method of contraception was coitus interruptus (56%), 22% of patients had tubal ligation, 6% had husbands who had vasectomies, 14% were using condoms, and only 2% used oral contraceptives. Among 33 pregnancies, 16 were unintended (48.5%). Most of the patients with unwanted pregnancy were using coitus interruptus (93.7%). In the group with unintended pregnancy, abortion was induced in three, spontaneous abortion or intrauterine fetal death occurred in six, and only seven pregnancies resulted in a live birth (43.7%). CONCLUSION: Kidney transplantation greatly improves fertility, so those who do not desire pregnancy should be protected by an effective method of contraception. 相似文献