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目的    研究上颌后牙区剩余牙槽骨高度为3 ~ < 4 mm时,行经牙槽嵴顶上颌窦底提升或侧壁开窗上颌窦底提升同期种植体植入的短期临床效果。方法    选择2016年1月至2018年12月于西安交通大学口腔医院种植科行经牙槽嵴顶上颌窦底提升和侧壁开窗上颌窦底提升同期种植体植入的患者45例(50侧上颌窦,上颌后牙区剩余牙槽骨高度为3 ~ < 4 mm),于术前、术后当日或术后第2天及术后6 ~ 9个月的愈合期后行影像学检查,比较两种术式的上颌窦底新骨形成高度、上颌窦底黏膜穿孔率及种植体早期成功率。结果   采用经牙槽嵴顶上颌窦底提升或侧壁开窗上颌窦底提升同期种植体植入的分别有19例和26例(上颌窦分别为21、29侧)患者;上颌窦底黏膜穿孔率分别为4.76%和0,差异无统计学意义(P > 0.05)。经过6 ~ 9个月的愈合期,两种术式上颌窦底新骨形成高度分别为(5.18 ± 0.48)mm和(7.32 ± 0.84)mm,差异有统计学意义(P < 0.05);两种术式种植体早期成功率分别为95.83%和100%,差异无统计学意义(P > 0.05)。结论    当上颌后牙区剩余牙槽骨高度为3 ~ < 4 mm时,两种术式均安全可靠,早期成功率高。  相似文献   
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ObjectiveThe aim of study was to analyze the association between Quadriceps Angle (QA) and plantar pressure, navicular height (NH), and calcaneo-tibial angle (CTA).MethodsA total of 64 volunteers (mean age: 22.25 ± 2.54 (range:19–33)) participated in this cross sectional study. EMED-m (Novel GmbH, Germany) electronic pedobarograph was employed for dynamic plantar pressure measurement using two step protocol. The angle between the vertical axis of calcaneus and the long axis of Achilles tendon for CTA. The height of navicular tubercle from the ground was measured while the subject was standing on both feet for NH. QA was measured while the subject was standing in a relaxed posture where both feet bearing equal weight.ResultsThere were significant negative correlations between QA and maximum force (MxF) under the 4th. metatarsal head (MH4). The QA was also significantly correlated with MxF and force-time integral (FTI) under the bigtoe (BT). FTI under the 3rd. metatarsal head (MH3), MH4 and 5th. metatarsal head (MH5) were significantly negatively correlated with QA. Pressure-time integral (PTI) under the MH4 and MH5 were found to be significantly negatively correlated with QA. A significant correlation was also found between QA and NH (p < 0.0001), whilst there was no correlation between QA and CTA. Regression analysis showed that NH was appeared as the major contributor for the QA (β = −0.49, p < 0.001) in the dynamic condition, followed by BT-FTI (β = 0.37, p < 0.001) and MH5-MxF (β = −0.21, p < 0.037).ConclusionThese findings may imply that the NH which can at least be controlled by appropriate shoe inserts may affect QA. This way, loading pattern of both plantar region and whole lower extremity may be altered.Level of evidenceLevel III, Diagnostic Study.  相似文献   
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BackgroundMedial meniscus (MM) translates and extrudes posteriorly during knee flexion in MM posterior root tear (MMPRT) knees, and transtibial pullout repair of MMPRT has been performed to regulate the MM extrusion. This study aimed to calculate each suture translation during knee flexion in transtibial pullout repair of MMPRT, and to investigate the morphologic features of the MM that lead to longer suture translations during knee flexion.MethodsThirty patients with MMPRT who met the operative indication of pullout repair were enrolled and investigated prospectively. Pullout repair was performed by using two simple stitches (outer and inner sutures) and an all-inside suture in the posteromedial part of the MM. Each suture’s translation from 0° to 90° of knee flexion was measured intraoperatively. The MM morphologic features, including MM medial extrusion (MMME) and MM posterior height (MMPH), were measured using preoperative magnetic resonance imaging, and the correlation between these values and each suture translation was evaluated.ResultsThe average outer, inner, and all-inside suture translations were 4.8 mm, 3.9 mm, and 1.3 mm, respectively. Significant correlations were observed between the outer suture translation and MMME, and MMPH (p < 0.001 and <0.01, respectively). The thresholds for preoperative MMME and MMPH for longer outer suture translations (≥6 mm) were 2.1 mm and 5.4 mm, respectively.ConclusionsPreoperative longer MMME and higher MMPH were associated with longer meniscus translations during knee flexion during MMPRT repair.  相似文献   
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BackgroundPercutaneous-short segment screw fixation (SSSF) without bone fusion has proven to be a safe and effective modality for thoracolumbar spine fractures (TLSFs). When fracture consolidation is confirmed, pedicle screws are no longer essential, but clear indications for screw removal following fracture consolidation have not been established.MethodsIn total, we enrolled 31 patients with TLSFs who underwent screw removal following treatment using percutaneous-SSSF without fusion. Plain radiographs, taken at different intervals, measured local kyphosis using Cobb’ angle (CA), vertebra body height (VBH), and the segmental motion angle (SMA). A visual analogue scale (VAS) and the Oswestry disability index (ODI) were applied pre-screw removal and at the last follow-up.ResultsThe overall mean CA deteriorated by 1.58° (p < 0.05) and the overall mean VBH decreased by 0.52 mm (p = 0.001). SMA preservation was achieved in 18 patients (58.1%) and kyphotic recurrence occurred in 4 patients (12.9%). SMA preservation was statistically significant in patients who underwent screw removal within 12 months following the primary operation (p = 0.002). Kyphotic recurrence occurred in patients with a CA ≥ 20° at injury (p < 0.001) with a median interval of 16.5 months after screw removal. No patients reported worsening pain or an increased ODI score after screw removal.ConclusionScrew removal within 12 months can be recommended for restoration of SMA with improvement in clinical outcomes. Although, TLSFs with CA ≥ 20° at the time of injury can help to predict kyphotic recurrence after screw removal, the clinical outcomes are less relevant.  相似文献   
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目的 了解云南省7个民族学生月经初潮和首次遗精与形态发育之间的关系,为研究学生生长发育规律和开展青春期性教育提供依据。方法 利用2014年全国学生体质健康调研数据,分析云南省7个民族学生月经初潮和首次遗精对身高、体重、胸围和维尔维克指数的影响。结果 男生性成熟年龄晚于女生,2014年云南省7个民族女生月经初潮半数年龄最小为汉族(12.28岁)、傣族(12.40岁),最大为哈尼族(13.06岁)、傈僳族(13.04岁),男生首次遗精半数年龄最小为佤族(13.43岁)、纳西族(14.01)岁,最大为傈僳族(15.29岁)、哈尼族(14.60岁);女生来潮组的形态发育状况好于未来潮组(P值均<0.05),男生已遗精组与未遗精组的差异,只有部分项目有统计学意义。结论 应针对不同性别、种族、地域特点,适时适量进行青春期性教育,加强少数民族学生的膳食营养,改变不合理膳食结构和饮食习惯,强化体育锻炼,更好地促进学生的生长发育。  相似文献   
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PurposeThe present study aimed at the comparison of body height estimations from cadaver length with body height estimations according to Trotter and Gleser (1952) and Penning and Riepert (2003) on the basis of femoral F1 section measurements in post-mortem computed tomography (PMCT) images.MethodsIn a post-mortem study in a contemporary Swiss population (226 corpses: 143 males (mean age: 53 ± 17 years) and 83 females (mean age: 61 ± 20 years)) femoral F1 measurements (403 femora: 199 right and 204 left; 177 pairs) were conducted in PMCT images and F1 was used for body height estimation using the equations after Trotter and Gleser (1952, “American Whites”), and Penning and Riepert (2003).ResultsThe mean observed cadaver length was 176.6 cm in males and 163.6 cm in females. Mean measured femoral length F1 was 47.5 cm (males) and 44.1 cm (females) respectively. Comparison of body height estimated from PMCT F1 measurements with body height calculated from cadaver length showed a close congruence (mean difference less than 0.95 cm in males and less than 1.99 cm in females) for equations both applied after Penning and Riepert and Trotter and Gleser.ConclusionsFemoral F1 measurements in PMCT images are very accurate, reproducible and feasible for body height estimation of a contemporary Swiss population when using the equations after Penning and Riepert (2003) or Trotter and Gleser (1952).  相似文献   
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ObjectiveTo determine the prevalence of chronic ankle instability (CAI) and to investigate its relationship to the foot arch in collegiate female athletes by each sports event.DesignCross-sectional study.SettingUniversity setting.Participants138 collegiate female athletes.Main outcome measuresAll subjects were asked about previous ankle sprains, and the arch height index (AHI) was calculated. Athletes with a previous sprain history were evaluated based on the criteria by the International Ankle Consortium (IAC), the severity of ankle instability (CAIT), and foot and ankle function (FAAM). The prevalence of CAI and the relationship between the AHI and ankle instability were analyzed by each sports event.ResultsOf 106 athletes with a previous ankle sprain, 10 (9.4%) met the IAC criteria below the cut-off value of the CAIT, and only 1 athlete (0.9%) was below the FAAM cut-off value. The AHI was not significantly different in athletes with CAI. The AHI was significantly lower in swimmers than in track and field (sprint) athletes.ConclusionMost female athletes with CAI were aware of the severity of ankle instability, but they did not feel dysfunction of the ankle during sports. Additionally, the AHI may depend on the characteristics of sports events.  相似文献   
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