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91.
A. P. Dei Tos Paola Dal Cin 《Virchows Archiv : an international journal of pathology》1997,431(2):83-94
Soft tissue tumours represent a heterogeneous group of mesenchymal lesions, and their classification is the subject of continuous
debate. Chromosome analysis, molecular cytogenetics and molecular assays may become increasingly useful in diagnosis, and
this review summarises advances in the cytogenetic characterisation and classification of soft tissue tumours. Among the group
of fibrous lesions, superficial fibromatosis exhibits trisomy 8. This genomic change is also observed in desmoid fibromatosis
in association with trisomy 20. Trisomy 11 is the most frequently observed chromosomal aberration in congenital fibrosarcoma.
Dermatofibrosarcoma protuberans and giant cell fibroblastoma share a translocation t(17;22), which supports the concept of
the existence of a common differentiation pathway. Adipose tissue tumours is the group in which integration of genetics and
pathology has been most fruitful. Ordinary lipomas cytogenetically show an abnormal karyotype in about half the cases. Genomic
changes of the 11q13 region are observed in hibernoma. Lipoblastoma exhibits a specific 8q rearrangement in 8q11-q13. Loss
of material from the region 16q13-qter and 13q deletions are observed in spindle cell/pleomorphic lipomas. The well-differentiated
liposarcoma/atypical lipoma group is characterised karyotypically by the presence of one extra ring and/or extra giant chromosome
marker. Myxoid and round cell liposarcoma share the same characteristic chromosome change: t(12;16)(q13;p11) in most cases.
In the group of smooth muscle lesions most data are derived from uterine leiomyomas, which can be subclassified cytogenetically
into seven different types. Half of all leiomyomas are chromosomally normal; the other half have one of six possible consistent
chromosome changes. Alveolar rhabdomyosarcoma is characterised cytogenetically by two variant translocations t(2;13)(q35;q14)
and t(1;13)(p36;q14). Among tenosynovial tumours, the localised type of giant cell tumour of tendon sheath exhibits two different
karyotypic changes. One involves 1p11 in a translocation with chromosome 2 or with another chromosome. A second type involves
16q24. Synovial sarcoma is characterised cytogenetically by a translocation occurring between chromosome 18 and presumably
two adjacent loci on the X chromosome. In neural tumours, abnormalities of chromosome 22 have been reported in benign schwannomas
and perineuriomas. Malignant peripheral nerve sheath tumours exist in two main forms: sporadic and associated with the NF-1
syndrome. Karyotypes are very complex, but chromosomes 17q and 22q are very often involved. Clear cell sarcoma is characterised
cytogenetically and molecularly by a translocation t(12;22)(q13;q12). The Ewing’s sarcoma/peripheral neuroectodermal tumour
category shows a central karyotypic anomaly represented by the translocation t(11;22). The two variants t(21;22) and t(7;22)
are found in some cases. Among cartilaginous lesion, the most frequently described anomaly is the t(9;22)(q22;q12) in extraskeletal
myxoid chondrosarcoma. Intra-abdominal desmoplastic small round cell tumour is characterised by a t(11;22)(p13;q12).
Received: 5 February 1997 / Accepted: 24 February 1997 相似文献
92.
Hiroyuki Hamakawa Hiroaki Kayahara Hiroaki Tanioka 《International journal of oral and maxillofacial surgery》1997,26(6):440-442
We describe a procedure for “chain-link” combined tissue transfer connecting the vascular pedicle of a deep circumflex iliac flap with that of a forearm flap after wide resection of the mandible. Combination of these flaps facilitated the reconstruction of the defect in both intra- and extraoral soft tissue and the mandibular bone. This method is useful when cervical recipient blood vessels are limited due to the wide resection of the primary tumor and radical neck dissection. 相似文献
93.
94.
Joseph Leighton 《Methods in Cell Science》1992,14(4):201-207
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity. 相似文献
95.
The effects of training, immobilization and remobilization on musculoskeletal tissue 总被引:2,自引:0,他引:2
P. Kannus L. Jozsa P. Renström M. Järvinen M. Kvist M. Lehto P. Oja I. Vuort 《Scandinavian journal of medicine & science in sports》1992,2(4):164-176
Compared with the knowledge on immobilization, the effects of remobilization on musculoskeletal tissues have not been well established. What is sure is that remobilization and rehabilitation of any component of the musculoskeletal tissues require much more time than the time needed to cause the immobilization atrophy. With intensive rehabilitation, the functional properties of skeletal muscles can be improved significantly even years after the injury and following immobilization, but no study has shown whether full recovery is possible and whether these rehabilitated muscles are able to respond normally to further training. Experimental studies have given evidence that slow-twitch muscle fibres have better capacity for recovery than fast-twitch fibres, most likely due to better circulation and higher protein turnover. Also evidence has been given that fibre regeneration is possible through satellite cell activation and myotube formation. Very little is known, however, about the effects of age, gender or the level of preimmobilization muscle performance on the restoration capacity. Also the fate of the marked structural changes (for example, connective tissue accumulation) induced by immobilization is unknown. Tendon and ligament tissues are likely to respond appropriately to remobilization, resulting in acceleration of collagen synthesis and fibril neoformation. However, there is a strong suspicion that remobilized tendons and ligaments will not achieve all the biochemical and biomechanical properties of their healthy counterparts. Specifically, the amount of weak type III collagen has been shown to be overrepresented in these tissues instead of mature, strong type I collagen. It is not known whether this is an important risk factor for ruptures during later activity. The effects of remobilization on muscle-tendon junction and proprioceptive organs are not known. It would not be surprising if the serious structural changes induced by immobilization were unrestorable. In the literature dealing with immobilization and remobilization, cartilage degeneration is always a major concern, because not only too strenuous training or immobilization, but also unskilful remobilization may activate this process leading finally to osteoarthrosis. Bone may be one of the best components of musculoskeletal tissues to respond to remobilization, probably because the immobilization atrophy of bone is largely quantitative (osteoporosis) only. The prerequisites for bony recovery are that the follow-up time is long enough (months) and that immobilization has not exceeded about 6 months, the time limit between active and inactive (irreversible) osteoporosis. Prevention of the atrophying effects of immobilization can be very successful if performed properly. According to present knowledge, there are many methods for the purpose, including preimmobilization training early, controlled mobilization; optimal positioning of the immobilized joint; muscular training during immobilization; early weightbearing; exercise with the nonimmobilized extremity; and electrical stimulation. Lots of education and information will be needed, however, before these methods are deeply rooted in the daily routines of the attending physicians, physical therapists, athletic trainers and other persons involved in the treatment of musculoskeletal problems. 相似文献
96.
微量地塞米松与抗病毒药物合用对抗单疱病毒作用的影响 总被引:9,自引:0,他引:9
报告在组织培养中地塞米松对单纯疱疹病毒(HSV)的生长繁殖无影响,对无环鸟苷(ACV)和环胞苷(CC)的抗病毒作用亦无干扰。在动物实验中,微量地塞米松[0.001%,常用浓度(0.1%)的百分之一]并不恶化上皮型HSV角膜炎。同时证明有效抗病毒药物的合用,微量地塞米松仍保留有良好的消炎作用,能促进上皮型和实质层型单疱角膜炎的痊愈过程。 相似文献
97.
98.
糖尿病大鼠肺病理改变及同期肾脏病理变化对比 总被引:3,自引:0,他引:3
目的:观察糖尿病(DM)大鼠肺组织改变及与同期肾脏变化的关系.方法:链脲菌素腹腔注射制作糖尿病大鼠模型,4周后胶原、网状纤维染色及透射电镜方法观察糖尿病大鼠肺组织基底膜病理改变,同期观察肾脏改变.结果:DM大鼠4周后肺组织病理改变为毛细血管基底膜及Ⅱ型肺泡上皮细胞基底膜不同程度的增厚及肺间质胶原成分等细胞外基质的增多,与同期糖尿病肾脏病变相平行.结论:DM大鼠4周后肺组织与糖尿病肾病相似,主要表现为微血管病变. 相似文献
99.
骨髓间质干细胞体外预构组织工程化肌腱的实验研究 总被引:2,自引:1,他引:1
目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱. 相似文献
100.
Experimental Study on Allogenic Decalcified Bone Matrix as Carrier for Bone Tissue Engineering 总被引:11,自引:0,他引:11
The biocompatibility and osteogenic activity of allogenic decalcified bone matrix (DBM) used as a carrier for bone tissue engineering were studied. Following the method described by Urist, allogenic DBM was made. In vitro, DBM and bone marrow stromal cell (BMSC) from rab-bits were co-cultured for 3-7 days and subjected to HE staining, and a series of histomorphological observations were performed under phase-contrast microscopy and scanning electron microscopy (SEM). In vivo the mixture of DBM/BMSC co-cultured for 3 days was planted into one side of muscules sacrospinalis of rabbits, and the DBM without BMSC was planted into other side as con-trol. Specimens were collected at postoperative week 1, 2 and 4, and subjected to HE staining, and observed under SEM. The results showed during culture in vitro, the BMSCs adherent to the wall of DBM grew, proliferated and had secretive activity. The in vivo experiment revealed that BMSCs and undifferentiated mesenchymal cells in the perivascular region invaded gradually and proliferated together in DBM/BMSC group, and colony-forming units of chondrocytes were found. Osteoblasts,trabecular bone and medullary cavity appeared. The inflammatory reaction around muscles almost disappeared at the second weeks. In pure DBM group, the similar changes appeared from the sur-face of the DBM to center, and the volume of total regenerate bones was less than the DBM/BMSC group at the same time. The results indicated that the mixture of DBM and BMSC had good bio-compatibility and ectopic induced osteogentic activty. 相似文献