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[摘 要] 目的 探讨颈部淋巴结结核超声造影特征性增强模式的诊断效能。方法 收集病理或实验室确诊的颈部淋巴结肿大病例226例,分析淋巴结结核的超声造影特征性增强模式在结核性与非结核性淋巴结病变上的差异,并统计分析其诊断效能。结果 颈部淋巴结结核在超声造影上常表现为淋巴结内部不均匀增强和淋巴结周边环形增强。在确诊的104例颈部淋巴结结核中,85例表现为内部不均匀增强(与非结核组比较,P < 0.01),其诊断敏感性为81.73%,特异性79.51%;有89例表现为淋巴结周围环形增强(与非结核组比较,P < 0.01),其诊断敏感性为85.58%,特异性87.70%;76例既有内部不均匀增强又有周围环形增强(与非结核组比较,P < 0.01),其诊断敏感性为73.08%,特异性94.44%。结论 超声造影能较好地评估淋巴结内部的增生与坏死情况;淋巴结内部不均匀增强和淋巴结周围环形增强是颈部淋巴结结核的超声造影特征性征象,可为其诊断和鉴别诊断提供帮助。  相似文献   
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《Cirugía espa?ola》2023,101(8):548-554
IntroductionPelvic fractures due to high energy trauma present a high risk of associated injuries that compromise the functional and vital prognosis of the patients. The objective of this study was to analyze the relationship between traumatic pelvic fractures and their associated injuries according to the Tile classification.MethodsRetrospective observational study of patients who suffered traumatic pelvic fractures (Type A, B or C of the Tile classification) with concomitant associated injuries, analyzing hemoglobin levels, between 6/2013 and 1/2016.ResultsA total of 42 patients were included; of those 69% (n = 29) were males, mean age was 48 years. 45% (n = 19) suffered traffic accidents and 26.2% (n = 11) falls. There was a different proportion in pelvic injuries: Tile A (n = 15, 35.7%), B (n = 20, 47.6%), and C (n = 7, 16.6%) of cases. 54.8% (n = 23) underwent surgery, 21.4% (n = 9) needed temporary or definitive external fixation. Significant differences were found between Tile A type and scapula fractures (P=.032), and Tile B with sacral fractures (P=.033) and visceral injuries (P=.049), while there is a tendency without a statistical significal between Tile C and costal fractures. 61.9% (n = 26) needed blood transfusion; 9.5% (n = 4) presented hypovolemic shock.ConclusionsTile A pelvic fractures were associated with scapular fractures, and Tile B with transforaminal fractures of the sacrum and with visceral injuries (lungs, liver and genitourinary). The small number of Tile C prevent us to confirm an association with any pathology, although they are the ones which presnt more hemodynamically instability and thoracic injuries.  相似文献   
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目的:比较HyperArc、容积旋转调强(VMAT)和射波刀(CyberKnife)在单发和多发脑转移瘤(BM)放射治疗中的剂量学差异。方法:将75例脑转移瘤CT图像分成5组(1 BM、4 BM、8 BM、15 BM、20 BM),分别设计HyperArc、非共面VMAT和CyberKnife这3种不同技术(HA、nCO-VMAT、CK)的计划。分析比较3种计划的剂量学差异,包括靶区适形度指数(CI)、梯度指数(GI)、正常脑组织平均剂量(Brainmean)、机器总跳数(MU)以及出束时间。结果:在1 BM中,HA、nCO-VMAT、CK的GI值(P=0.429)和Brainmean值(P=0.799)接近;HA和nCO-VMAT的CI值接近,优于CK(P<0.001)。在4 BM中,HA、nCO-VMAT、CK的GI值(P=0.334)和Brainmean值(P=0.317)都接近;HA和nCO-VMAT的CI值接近,优于CK(P<0.001)。在8 BM中,HA和nCO-VMAT的CI值接近,优于CK(P<0.001);HA和CK的GI值接近,优于nCO-VMAT(P<0.001)。在15 BM中,HA的CI值(P<0.001)最优;CK的GI值(P<0.001)最优,HA次之,nCO-VMAT最差;CK的Brainmean值(P<0.001)最优,HA次之,nCO-VMAT最差。在20 BM中,HA的CI值(P<0.001)最优;CK的GI值(P<0.001)最优,HA次之,nCO-VMAT最差。在所有组中HA和nCO-VMAT的MU值都比CK低,CK的出束时间都远大于HA和nCO-VMAT。结论:HA、nCO-VMAT与CK技术都可以降低正常脑组织的剂量,都能取得很好的CI和GI,但HA出束时间短,CK出束时间长。  相似文献   
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AimTo evaluate the surgery program strategy adopted in an adult otorhinolaryngology and head and neck surgery department in an area badly affected by the Covid-19 epidemic peak. The main objective was to analyze the reasons for not cancelling surgeries and the postoperative course of operated patients. The secondary objective was to assess the situation of postponed patients.Material and MethodsA single-center observational study carried out during the COVID-19 period in France included 124 patients scheduled for surgery during the period March 21-May 20, 2020. The number and nature of operations, both performed and postponed, were reviewed.ResultsA total of 54.0% patients were operated on during the COVID period and 46.0% were postponed. Operations were maintained in urgent or semi-urgent cases. The operated patients did not show any signs of infection during their hospital stay. A total of 29.8% of postponed patients were lost to follow-up and 49.1% were rescheduled.ConclusionThe application of national and international recommendations minimized the risk of loss of chance for operated patients without increasing the risk of contamination. The postponement of canceled operations resulted in considerable loss to follow-up. Intensified follow-up is necessary for these patients.  相似文献   
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《Dental materials》2022,38(11):1789-1800
ObjectivesDentin microstructure undergoes changes with age and its materials properties degrade over time. In the present study, we investigate the coupled influence of increased filled tubules and decreased materials properties on the fracture behavior of human dentin.MethodsWe assume degraded materials properties are linked with increased advanced glycation end-products (AGEs) crosslinks in dentin tissue. We use morphological data of human molars to create 2D and 3D models of dentin microstructure, and utilize a phase field fracture framework to study crack growth trajectories. We construct aged dentin samples (i.e., filled tubules and degraded properties) and compare the fracture results with the samples without age-related changes.ResultsThe simulations show an increase in the number of filled tubules can deactivate the toughening mechanisms such as crack deflection and microcracking. In addition, filled tubules have adverse impacts on the ability of peritubular dentin to shield microcracking. We further show how the dentinal tubules’ orientations affect the crack surface growth. We also investigate that an increase in the AGEs level can result in increased brittleness.SignificanceThe developed model and findings of the present study provide region-dependent information on crack growth trajectories as well as more understanding of crack surface growth at the presence of filled tubules.  相似文献   
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目的 探讨骨科康复一体化模式下髋臼骨折围手术期康复临床路径的有效性和安全性。  相似文献   
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BackgroundThe treatment of complex 3- and 4-part proximal humerus fractures (PHFs) in the elderly poses significant challenges because of osteoporosis and fracture comminution. The wide range of surgical options available is evidence of the complex nature of the injury. At present, reverse shoulder replacement is gaining popularity among shoulder surgeons for treating these difficult fractures, and the literature has shown equivalent or superior outcomes with reverse shoulder arthroplasty (RSA). We aimed to analyze the long-term results of these complex PHF treated with reverse shoulder replacement.MethodsFor this study, fractures from 39 patients with a mean age of 63.18 years who were treated with RSA for acute complex fractures of the proximal humerus in our institution between 2013 and 2019 were analyzed (n = 31, acute 4-part fractures; n = 4, acute fracture–dislocation; n = 3, fracture with irreparable cuff tear; n = 1, osteoporotic 2-part fracture). All patients had a standard reverse shoulder replacement (cemented humeral stem n = 37 and uncemented stem n = 2) surgery in a level 1 trauma center. The mean follow-up duration was 60 months (24-111 months). The clinical outcomes (Oxford Shoulder Score and Constant Shoulder Score) and the complications at 6 months, 12 months, and 24 months were analyzed.ResultsOur study found a relatively younger population, with 21 patients (53.84%) aged <66 years. Spearman's correlation showed that younger patients had better signs of improvement in Oxford Shoulder Scores at 2 years (P = .008). The average Oxford Shoulder Score was 39.12 ± 4.327, and the average Constant Shoulder Score was 67.67 on the operated side. The mean active forward elevation was 142.56 ± 22.29º, abduction was 136.538 ± 24.31º, external rotation was 27 ± 9.011º, and internal rotation was 33 ± 20.41º. The overall complication rate of 17.94% (periprosthetic infection n = 2, periprosthetic humerus fracture n = 1, and hematoma evacuation n = 4) in our study was similar to those of recent studies in the literature.ConclusionRSA provides a reliable option for PHFs and offers good results in the form of pain relief and good functional outcomes at 2 years even in a younger age group. Thus, it is fast becoming an important option in treating complex PHF, but we must be wary of the steep learning curve and the complications pertinent to this procedure.  相似文献   
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Background: The incidence of Head and neck (HN) cancers in Thailand is rising and survival rates not improving. Variations of its incidence among geographical areas may due to various contributing factors. Methods: We focused on data from 25 districts within Chiang Mai province, Thailand. The temporal change was described separately into two periods, 2007-2012 and 2013-2018. The OpenBUGS and the Quantum Geographic Information System were utilized to determine the geographical patterns in the incidence of HN cancer and focus on oropharynx. Results: The number of new cases of HN cancer was 1,186, of which 835 cases (70%) were male. Among those patients 548 diagnosed in 2007-2012 and 638 diagnose in 2013-2018. High risk patterns of both overall HN and oropharyngeal cancer incidences were found in the central and southern areas of the province in 2007-2013. However, the geographical patterns of the incidence of oropharyngeal cancer showed the changed pattern, with high RR in central and northern areas in more recent period. Over two periods, the RR of the cancers incidence decrease. The RR of oropharyngeal increased in Fang district and it remained high in Mueang district. Conclusion: This study have highlighted specific areas with a high risk of head and neck cancer and oropharyngeal cancer incidences in Chiang Mai province, along with the spatial inequalities in their distributions, with cluster formation. These results may be helpful in guiding any strategy put in place to respond to the high risk incidence of the cancers in specific areas.  相似文献   
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