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81.
Purpose: The purpose of the present study was to evaluate the efficacy and safety of levetiracetam (LEV) in refractory epileptic children. Methods: The study group included 61 outpatients (7 generalized, 48 localization-related, 3 undetermined, 3 unclassified) aged between 16 months and 18 years. LEV was given twice daily at a total dose of 10 mg/kg/day. The final mean dose was 50.7 mg/kg/day. The mean number of prior anti-epileptic drugs was 5.2. The entire treatment period was more than 6 months after LEV administration. Results: Fifteen children (24.6%) became seizure-free for 6 months after starting LEV, and 18 (29.5%) had a seizure reduction of more than 50% for the entire 6 months. The response rate was 33/61 (54.1%). Responders included 2/3 of patients (66.7%) with epilepsy with continuous spikes and waves during slow sleep and 13/19 (68.4%) with frontal lobe epilepsy. The effective dosage of LEV in the responders demonstrated a wide range (mean, 46.1 mg/kg/day; range, 19.4–59.1 mg/kg/day), and showed bimodal distribution. Adverse events occurred in only two patients who did not require LEV discontinuation. Conclusion: LEV represents an important addition to the treatments available for refractory epileptic children. 相似文献
82.
83.
《Neuromodulation》2022,25(8):1421-1430
ObjectivesMotion sickness (MS) is a common physiological response to real or virtual motion. The purpose of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on MS and the underlying mechanisms in healthy subjects.Materials and MethodsA total of 50 healthy participants were recruited and randomly assigned into two groups to complete two separate sessions in a crossover study. A Coriolis rotary chair was used as a model to provoke severe MS. The total tolerable rotation time and Graybiel scoring scale were recorded. Gastric slow waves were detected by electrogastrogram. The autonomic nervous function, including the vagal activity, was evaluated by the analysis of heart rate variability derived from the electrocardiogram recording. The serum levels of arginine vasopressin (AVP) and norepinephrine (NE) were examined.ResultsOf note, 22 participants in TEA and only 11 participants in the sham-TEA session completed the entire five-rotation MS stimuli (p = 0.019). TEA significantly prolonged the total tolerable rotation time of MS stimuli (220.4 ± 11.59 vs 173.6 ± 12.3 seconds, p < 0.001) and lowered MS symptom scores (12.56 ± 2.03 vs 22.06 ± 3.0, p < 0.001). TEA improved the percentage of normal gastric slow waves, compared with sham-TEA (56.0 ± 2.1% vs 51.6 ± 2.0%, p = 0.033). TEA also significantly enhanced vagal activity compared with sham-TEA (0.41 ± 0.02 vs 0.31 ± 0.02, p < 0.001). In addition, the increased serum levels of AVP and NE on MS stimulation were markedly suppressed by TEA treatment, compared with sham-TEA (AVP, 56.791 ± 4.057 vs 79.312 ± 10.036 ng/mL, p = 0.033; NE, 0.388 ± 0.037 vs 0.501 ± 0.055 ng/mL, p = 0.021).ConclusionsNeedleless TEA is a potent therapeutic approach for severe MS, as it increases participants' tolerance and ameliorates MS symptoms, which may be attributed to the integrative effects of TEA on autonomic functions and neuroendocrine balance. 相似文献
84.
《Anaesthesia and Intensive Care Medicine》2022,23(12):818-824
Magnetic resonance imaging (MRI) is a widely available imaging modality providing high-resolution images of soft tissues. The magnetic fields generated by these scanners create an array of safety challenges which require specialist equipment and trained staff to safely operate within this environment.Guidance exists for the anaesthetist working in the MR suite, though for many individuals it remains a less familiar environment and remote site for practising safe anaesthesia.We outline the specific concerns with commonly encountered implanted devices and some of the practicalities related to caring for patients with these devices in the MRI suite.Within neuroanaesthesia, advances in procedural techniques and technology in MRI lead to an increased number of patients requiring scanning for diagnosis and treatment progress.This includes patients on the critical care unit and intraoperatively in the interventional MRI suites. 相似文献
85.
目的针对传统电磁跟踪方法存在的依赖磁场模型具体磁感应强度值、迭代算法繁琐的问题,提出一种采用非迭代几何算法的电控旋转磁场跟踪方法,以避免模型误差、简化定位算法。方法采用三轴正交磁场源,通过控制磁场源三轴激励电流强度实现合成最大磁感应强度矢量在空间中遍历旋转,根据矢量指向三轴磁传感器时的旋转角利用非迭代几何算法进行定位,对该方法进行了仿真研究。结果仿真半径为0.3 m时,平均位置误差为0.32 cm,方差为0.02,定位时间为0.54 s。结论基于电控旋转磁场与非迭代几何算法的电磁跟踪方法可以较准确地定位传感器,具有定位速度快、性能稳定的潜在优势,值得进一步优化提高性能以满足介入式微创手术临床实用要求。 相似文献
86.
Effect of radial shock wave therapy for carpal tunnel syndrome: A prospective randomized,double‐blind,placebo‐controlled trial 下载免费PDF全文
Yung‐Tsan Wu Ming‐Jen Ke Yu‐Ching Chou Chih‐Ya Chang Ching‐Yueh Lin Tsung‐Ying Li Feng‐Mei Shih Liang‐Cheng Chen 《Journal of orthopaedic research》2016,34(6):977-984
Three recent studies demonstrated the positive effect of extracorporeal shock wave therapy (ESWT) for treating carpal tunnel syndrome (CTS). However, none have entirely proved the effects of ESWT on CTS because all studies had a small sample size and lacked a placebo‐controlled design. Moreover, radial ESWT (rESWT) has not been used to treat CTS. We conducted a prospective randomized, controlled, double‐blinded study to assess the effect of rESWT for treating CTS. Thirty‐four enrolled patients (40 wrists) were randomized into intervention and control groups (20 wrists in each). Participants in the intervention group underwent three sessions of rESWT with nightly splinting, whereas those in the control group underwent sham rESWT with nightly splinting. The primary outcome was visual analog scale (VAS), whereas the secondary outcomes included the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), cross‐sectional area (CSA) of the median nerve, sensory nerve conduction velocity of the median nerve, and finger pinch strength. Evaluations were performed before treatment and at 1, 4, 8, and 12 weeks after the third rESWT session. A significantly greater improvement in the VAS, BCTQ scores, and CSA of the median nerve was noted in the intervention group throughout the study as compared to the control group (except for BCTQ severity at week 12 and CSA at weeks 1 and 4) (p < 0.05). This is the first study to assess rESWT in a randomized placebo‐controlled trial and demonstrate that rESWT is a safe and effective method for relieving pain and disability in patients with CTS. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:977–984, 2016. 相似文献
87.
Both Asian (Elephas maximus) and African (Loxodonta africana) elephants produce low-frequency, high-amplitude rumbles that travel well through the ground as seismic waves, and field studies have shown that elephants may utilize these seismic signals as one form of communication. Unique elephant postures observed in field studies suggest that the elephants use their feet to 'listen' to these seismic signals, but the exact sensory mechanisms used by the elephant have never been characterized. The distribution, morphology and tissue density of Pacinian corpuscles, specialized mechanoreceptors, were studied in a forefoot and hindfoot of Asian elephants. Pacinian corpuscles were located in the dermis and distal digital cushion and were most densely localized to the anterior, posterior, medial and lateral region of each foot, with the highest numbers in the anterior region of the forefoot (52.19%) and the posterior region of the hindfoot (47.09%). Pacinian corpuscles were encapsulated, had a typical lamellar structure and were most often observed in large clusters. Three-dimensional reconstruction through serial sections of the dermis revealed that individual Pacinian corpuscles may be part of a cluster. By studying the distribution and density of these mechanoreceptors, we propose that Pacinian corpuscles are one possible anatomic mechanism used by elephants to detect seismic waves. 相似文献
88.
Babiloni C Bosco P Ghidoni R Del Percio C Squitti R Binetti G Benussi L Ferri R Frisoni G Lanuzza B Cassetta E Anello G Gurzì M Bartesaghi S Lizio R Tombini M Rossini PM 《Neuroscience》2007,145(3):942-954
High plasma concentration of homocysteine is an independent risk factor for Alzheimer’s disease (AD), due to microvascular impairment and consequent neural loss [Seshadri S, Beiser A, Selhub J, Jacques PF, Rosenberg IH, D’Agostino RB, Wilson PW, Wolf PA (2002) Plasma homocysteine as a risk factor for dementia and Alzheimer’s disease. N Engl J Med 346(7):476–483]. Is high plasma homocysteine level related to slow electroencephalographic (EEG) rhythms in awake resting AD subjects, as a reflection of known relationships between cortical neural loss and these rhythms? To test this hypothesis, we enrolled 34 mild AD patients and 34 subjects with mild cognitive impairment (MCI). Enrolled people were then subdivided into four sub-groups of 17 persons: MCI and AD subjects with low homocysteine level (MCI− and AD−, homocysteine level <11 μmol/l); MCI and AD subjects with high homocysteine level (MCI+ and AD+, homocysteine level ≥11 μmol/l). Resting eyes-closed EEG data were recorded. EEG rhythms of interest were delta (2–4 Hz), theta (4–8 Hz), alpha 1 (8–10.5 Hz), alpha 2 (10.5–13 Hz), beta 1 (13–20 Hz), and beta 2 (20–30 Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography (LORETA). Results showed that delta (frontal and temporal), theta (central, frontal, parietal, occipital, and temporal), alpha 1 (parietal, occipital, and temporal), and alpha 2 (parietal and occipital) sources were stronger in magnitude in AD+ than AD− group. Instead, no difference was found between MCI− and MCI+ groups. In conclusion, high plasma homocysteine level is related to unselective increment of cortical delta, theta, and alpha rhythms in mild AD, thus unveiling possible relationships among that level, microvascular concomitants of advanced neurodegenerative processes, and synchronization mechanisms generating EEG rhythms. 相似文献
89.
Computational and mathematical human eye models from previous studies which were constructed in two-dimensions (2D) did not give a precise representation of the actual human eye. This work is an extension from an earlier published work on the 2D model. In this paper, a 3D FEM model of the human eye is simulated for the steady state temperature distribution during normal condition and during electromagnetic (EM) wave radiation. Results show a discrepancy of 0.49% for a normal condition as opposed to 1.9% of a 2D model when compared to experimental results from open literatures. Investigations on the EM wave radiations found an average power absorption density of 15,151 and 22,145 Wm(-3) for the 750 and 1500 MHz radiation, respectively. A peak temperature of 38.18( composite function)C was predicted for the 750 MHz radiation while 41.19( composite function)C was computed for the 1500 MHz radiation. These temperatures are in reasonable agreement with the simulated results computed by another report in the past. 相似文献
90.
电磁导航支气管镜在肺外周病变诊断及治疗的临床应用 《首都医科大学学报》2022,43(4):570-575
随着低剂量螺旋电子计算机断层扫描(computed tomography,CT)应用于肺癌高危人群中的筛查越来越普及,肺外周病变(peripheral pulmonary lesions,PPLs)发现概率也随之增加。电磁导航支气管镜(electromagnetic navigation bronchoscopy,ENB)是一种能够进行肺部外周病变诊断、定位及治疗的工具,由于它的安全性和可靠性更高,ENB在未来有可能会改变肺部疾病的诊断和治疗方式,从而缓解病情甚至治愈肺癌,为肺癌的治疗开辟了新的路径。 相似文献