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61.
Over the last century, the morphogenesis of the vertebral column has been considered as a highly conserved process among anurans. This statement is based on the study of few metamorphic taxa, ignoring the role of developmental mechanisms underlying the evolution of specialized life‐histories. Direct development in anurans has been regarded as evolutionarily derived and involves developmental recapitulation and repatterning at different levels in all amphibian taxa studied so far. Herein, we analyze the vertebral column morphogenesis of the direct‐developing frog Eleutherodactylus johnstonei, describing the sequence of chondrification and ossification, based on cleared and double‐stained specimens from early stage embryos to adults. In general, our results show that the morphogenesis of the vertebral column in E. johnstonei recapitulates the ancestral tadpole‐like pattern of development. However, the analysis of the sequence of events using heterochrony plots shows important heterocronies relative to metamorphic species, such as a delay in the chondrification of the vertebral centra and in osteogenesis. These ontogenetic peculiarities may represent derived traits in direct‐developing frogs and are possibly correlated with its unusual life history. In addition, several features of the vertebral column of E. johnstonei are highly variable from its typical morphology. We report some malformations and small deviations, which do not seem to affect the survival of individuals. These anomalies have also been found in other frogs, and include many vertebral defects, such as vertebral fusion, and vertebral preclusion and/or induction. Anat Rec, 296:00000–#2013, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
62.
目的探讨关节镜技术和三柱锁定钢板治疗胫骨平台骨折的临床效果。方法采用关节镜技术和三柱锁定钢板固定治疗51例胫骨平台骨折,SehatzkerI~Ⅲ型35例,Ⅳ一Ⅵ型16例;其中,胫骨髁间嵴骨折并前交叉韧带损伤8例,后交叉韧带止点撕脱骨折8例,半月板损伤5例。结果本组随访12~24个月,平均13.6个月。膝关节功能参照Rasmussen评分:优24例,良20例,可6例,差1例,优良率达86.3%。无切口坏死,无固定失败及骨外露发生。有1例伤口感染。结论采用关节镜技术和三柱锁定钢板固定各种胫骨平台骨折是一种可靠方法。  相似文献   
63.
目的探讨脊髓侧角神经元在SOD1G93A转基因鼠发病过程中的变化特征。方法利用甲苯胺蓝染色及免疫组化的方法观察SOD1G93A转基因小鼠不同病变时期上、中、下胸髓侧角神经元的数量变化特征。结果甲苯胺蓝染色法定量研究发现不同时期SOD1G93A转基因小鼠上胸髓、下胸髓水平,症状前期和发病期神经元计数较终末期均有显著性差别(P<0.05);与对照组相比,终末期胸髓各段侧角神经元计数明显减少且有统计学意义;免疫组化发现SOD1G93A转基因小鼠上胸髓、中胸髓水平不同时期相比,症状前期和发病期乙酰胆碱酯酶(AchE)阳性神经元计数较终末期均有显著性差别(P<0.05);与对照组相比,发病期上胸髓及终末期中、下胸髓水平侧角AchE阳性神经元数量减少具有统计学意义;结论在SOD1G93A转基因鼠发病过程中,存在脊髓侧角神经元丢失,尤其是在疾病的终末期,上、中、下胸髓节段间无明显差异。  相似文献   
64.
目的探讨涉及后柱胫骨平台骨折的治疗策略。方法自2009-07—2014-10收集206例胫骨平台骨折的临床资料,研究涉及后柱的胫骨平台骨折的发病率。采用Schatzker法及罗从风三柱法分别对骨折进行分类,后柱再分为后内侧柱和后外侧柱,筛选出涉及后柱的胫骨平台病历。根据后柱骨折的类型,选择合适的手术方案。结果 206例获得随访平均15.6(12~36)个月。150例骨折涉及后柱,其中130例涉及后外侧柱,97例涉及后内侧柱。206例无一例出现血管、神经损伤、内固定物松动及断裂,术后12个月复查骨折均获得骨性愈合。术后1年复位不良者3例。结论涉及后柱的胫骨平台骨折发病率高,应根据骨折类型,采用合适的切口、内固定方式等,以获得良好治疗效果。  相似文献   
65.
目的 探讨双切口3至4块钢板固定治疗累及后内侧柱的Schatzker Ⅴ、Ⅵ型复杂胫骨平台骨折的临床疗效.方法 2013年1月至2015年12月采用前外侧联合后内侧倒L形双切口,外侧1块3.5 mm锁定钢板,内侧及后内侧2至3块3.5mm小钢板固定治疗累及后内侧柱的Schatzker Ⅴ、Ⅵ型复杂胫骨平台骨折患者15例,分析术后复位效果及随访时膝关节功能情况,评估手术临床疗效.结果 15例均获随访,随访时间18 ~30个月,平均24个月.术后骨折复位效果满意,末次随访时复位无丢失,骨折均愈合,膝关节活动度0 ~135°,平均115..膝关节功能采用HSS评分标准评定:优10例,良2例,可3例,差0例,优良率80%.结论 对于累及后内侧柱的SchatzkerⅤ、Ⅵ型复杂胫骨平台骨折,采用双切口,3至4块3.5 mm钢板固定,可以获得有效固定,膝关节功能恢复良好,并发症少,疗效满意.  相似文献   
66.
Refractory pain to the fourth and fifth tarsometatarsal (TMT) joint can be a source of disability and functional impairment. While pain has been attributed to injury, post-traumatic arthritis, arthrofibrosis, the principal causes of pain in the absence of arthritis are not well elucidated. The purpose of this study is to characterize arthroscopic pathology associated with chronic refractory pain to the fourth and fifth TMT joints. We retrospectively examined 24 patients that underwent arthroscopic surgery of the fourth and fifth TMT joints for refractory pain at our academic institution between 2015 and 2019. We used the Outerbridge classification for chondral lesions, the Kellgren Lawrence radiographic classification for osteoarthritis, and described intraarticular pathologies as acute hypertrophic synovitis, chronic synovial fibrosis, hyaline bands, meniscoid bodies, loose joint bodies, arthrofibrosis. Approximately, 31 of 45 TMT joints (68.9%) presented with radiographic evidence of arthritis. Approximately, 14 of 45 TMT joints (31.11%) were absent of radiographic signs of arthritis. The frequency of soft tissue pathology seen in these patients without radiographic evidence of arthritis was arthrofibrosis (87.5%), chronic synovial fibrosis (75.0%), and acute hypertrophic synovitis (62.5%). This is the first study to report arthroscopic pathologies associated with refractory pain to the fourth and fifth TMT joints.  相似文献   
67.
目的探讨分析手术治疗胫骨平台骨折的策略。方法回顾性分析我院在2011年3月至2013年10月收治的30例胫骨平台骨折患者的手术治疗情况,其中13例患者行双柱支撑固定植骨手术治疗,17例患者行单柱支撑固定植骨手术治疗。结果本组所有患者术后经过12年时间随访,参照Rasmussen膝关节功能评分,结果治疗优良者26例,优良率为86.7%,其中优17例,良10例,可2例,差1例。结论在确保骨折部良好血运的情况下,首先解剖复位胫骨平台,并进行支撑固定植骨手术治疗的手术治疗效果显著,固定更加持久、稳固,是一种安全有效的手术方法,值得在临床上进一步推广。  相似文献   
68.

Purpose

To determine the risk factors of neurologic deficits during PVCR correction, so as to help improve safety during and after surgery.

Methods

A consecutive series of 76 patients with severe and rigid spinal deformities who were treated with PVCR at a single institution between October 2004 and July 2011 were included in our study. Of the 76 patients, 37 were male and 39 female, with an average age of 17.5 years (range 10–48 years). There were 52 adolescent patients (with an age <18 years) and 24 adult patients (with an age ≥18 years). Preoperatively, postoperatively and 6 months after surgery, we performed systemically neurologic function evaluations of each patients through meticulous physical examination. Any new abnormality or deterioration in evaluation of neurologic function than preoperative is reckoned postoperative neurologic deficits. Ten variables that might affect the safety of neurologic deficits during PVCR procedures, including imaging factors, clinical factors and operational factors, were analyzed using univariate analysis. Then the variables with statistical difference were analyzed by using multi-factor unconditional logistic regression analysis.

Results

No patient in this series had permanent paraplegia and nerve root injury due to operation. Change of neurologic status was found in six patients after surgery. Results of single-factor comparison demonstrated that the following seven variables were statistically different (P < 0.05): location of apex at main curve (X 3), Cobb angle at the main curve at the coronal plane (X 4), scoliosis associated with thoracic hyperkyphosis (X 5), level of vertebral column resected (X 6), number of segmental vessels ligated (X 7), preexisting neurologic dysfunction (X 8), and associated with intraspinal and brain stem anomalies (X 9). The multi-factor unconditional logistic regression analysis revealed that X 8 (OR = 49.322), X 9 (OR = 18.423), X 5 (OR = 11.883), and X 6 (OR = 8.769) were independent and positively correlated with the neurologic deficit.

Conclusions

Preexisting neurologic dysfunction, associated with intraspinal and brain stem anomalies, scoliosis associated with thoracic hyperkyphosis and level of vertebral column resected are independent risk factors for neurologic deficits during PVCR procedure.  相似文献   
69.
Abetalipoproteinemia is an uncommon cause of ataxia and retinitis pigmentosa (RP). Most of the neurological and ocular manifestations occur secondary to deficiency syndromes that is consequent to fat malabsorption from the small intestine. In this report, we have described the phenotype of a young adult female who manifested with recurrent diarrheal illness in her first decade, followed by anemia, RP, and neurological involvement with progressive deafness, cerebellar and sensory ataxia, and subclinical neuropathy in her second decade of life. While RP and sensory ataxia due to vitamin E deficiency are well-recognized features of abetalipoproteinemia, deafness is rarely described. In addition, we have highlighted the abnormal posterior column signal changes in the cervical cord in this patient. Early recognition avoids unnecessary investigations and has a potential to retard the disease progression by replacing some of the deficient vitamins.  相似文献   
70.
目的观察脊柱外周型原始神经外胚层肿瘤(pPNET)的影像学表现。方法回顾性分析7例经病理证实的脊柱pPNET患者的影像学资料。结果 7例脊柱pPNET病例中,男性4例,女性3例。病变位于颈段(C2~7)1例,颈胸段(C7~T2)1例,胸段(T10~12)1例,腰段(L3~4、L4~5)2例,腰骶段(L1~S2)1例,骶段(S1~4)1例;其中,髓外硬膜内1例,硬膜外6例。MR(n=7)和CT(n=4)检查表现为硬膜内或硬膜外肿块,信号/密度不均,T1WI为等或稍低信号,T2WI为稍高信号,CT为等密度,增强扫描呈不同程度不均匀强化。肿瘤位于髓外硬膜内者可伴有多发蛛网膜下腔转移,硬膜外pPNET肿瘤的主体部分多位于椎骨或椎旁组织,肿块椎管内部分累及多个椎体平面,并通过椎间孔、骶孔与椎旁部分沟通。结论脊柱pPNET可表现为髓外硬膜内或硬膜外肿瘤,确诊依赖病理及免疫组化检查。  相似文献   
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