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1.
An anatomical study of the facial artery   总被引:9,自引:0,他引:9  
The anatomical variations encountered in the dissection of 50 facial arteries in 25 adult preserved cadavers are presented. The facial artery was symmetrical in 17 of 25 (68%) of the dissections. The facial artery terminated as an angular facial artery in 34 (68%), a lateral nasal vessel in 13 (26%), and a superior labial vessel in 2 (4%); in 1 (2%) the facial artery terminated at the alar base. A longer course was identified in 5 (10%) facial arteries. The use of nasolabial flap (skin, full-thickness, and oral mucosa) raised as an island flap based on the facial artery or one its branches is discussed.  相似文献   
2.
Summary Prosthetic materials, such as metals, marlex mesh and methyl methacrylate have been used for stabilization of the chest wall after resection of large areas of rib cage. Such materials are contraindicated in an infected area. A new method of providing a stable chest wall using autogenous tissue is presented.  相似文献   
3.
Summary This paper describes a new technique for the division of syndactyly. The commissure is reconstructed by a dorsal trilobed flap and a zig zag incision which produces triangular flaps for the side of the digits. This technique does not require use of a skin graft. Seventeen syndactylies in fourteen children, nine incomplete (six congenital and three secondary to burn) and eight complete syndactylies were treated by this technique. The results after a maximum of twelve months follow-up and the advantages of the technique are discussed.[/ab]  相似文献   
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Image registration is an important step in the radiotherapy treatment planning process. It provides a method of fusing different types of diagnostic imaging information. One such application is to combine magnetic resonance spectroscopic images (MRSI) of the prostate with anatomical MRI and/or computed tomography images that are routinely used in the radiation treatment planning of prostate cancer. MRSI provides in vivo information related to the underlying metabolic activity of tissues, and can be related to the presence of cancer. However, the inflated endorectal coil required during MRS imaging poses a potential problem by deforming the prostate when it is filled with approximately 100 cm3 of air during image acquisition. This pushes the prostate superiorly/anteriorly, deforming the prostate and consequently the spectroscopic imaging data in a nonlinear manner. In this application, the coil-deformed MRS images are warped back to a non-deformed state, using a single data set. A nonlinear warping algorithm is presented to achieve this. Results indicate that the algorithm attains an accuracy of 97% (4 cm3 difference) when reproducing the total prostate volume compared to a Radiation Oncologist defined prostate volume. This difference is slightly smaller than the measured intra-operator variance of +/-1.5 cm3 (deflated coil) and the measured algorithm variance of +/-1.0 cm3. Additionally, intraprostatic nodules were used to assess the accuracy of the warping algorithm in regions inside the prostate. While choosing anatomical tie points along the external prostate surface, analysis of the nodules revealed the algorithm accuracy reduced to 63-93%.  相似文献   
6.
A 17 days old male infant, who had features of Down Syndrome, presented with fever, refusal to feed and seizures. He had papular, crusted skin lesions, moderate hepatosplenomegaly and a rapid downhill course. Peripheral blood and bone marrow aspirate showed features of acute leukaemia. Congenital Leukaemia is a rare malignancy associated with a very poor prognosis. Paradoxically, many cases of Congenital Leukaemia, especially in infants with Down Syndrome, show spontaneous remission.  相似文献   
7.
Summary After occlusion of the renal veins rats die quickly in progressive shock (within 4.5 h), but after ligating the renal hilum of both Kidneys they survive 27 h. To learn why renal vein occlusion is so rapidly lethal, and what substances are given off and by what method from the hemorrhagically infarcted kidneys, we studied eight groups of rats, each containing at least seven animals. The groups differed in the combination of hilar structures (renal veins, ureters, lymphatics) ligated. We compared: survival times, changes in blood pressure, blood volume, levels of plasma kinins, adenosine, and lactate, changes of blood pH, responses to Indomethacin, Trasylol®, and plasma expanders, tubular and capillary flow rates, histopathological changes in organs and cerebral blood flow and changes in the blood coagulation system. Our results suggest that the venous stasis, anoxia, and hemorrhagic necrosis caused by bilateral venous occlusion release into renal lymphatics toxic substances which reach the systemic circulation and induce irreversible shock. We have excluded prostaglandins and adenosine as the toxic substances inducing shock but could not rule out an action of the kallikrein-kinin-system. We postulate that the striking degenerative changes occurring in the arterioles of the brain after bilateral venous occlusion may mean these vessels are especially susceptible to high levels of lactic acid and that this may explain why these animals die so quickly. Our conclusions should help not only in understanding why high levels of lactate in shock portend a poor prognosis but also help in formulating appropriate therapy for circulatory failure of renal origin and for protracted hypotension after extensive tissue injury.The studies were supported by the German Research Foundation within the SFB 90 Cardiovasculäres SystemPresented in part: Jäckh and Steinhausen, 1976; Dallenbach et al., 1978; Zimmerhackl et al., 1979We dedicate this paper to Wilhelm Doerr, Dr. med., Professor of Pathology, University of Heidelberg on the occasion of his 65th birthday (August 25th, 1979)  相似文献   
8.
The mutational spectrum of brachydactyly type C   总被引:3,自引:0,他引:3  
Growth/differentiation factor-5 (GDF5), also known as cartilage-derived morphogenetic protein-1 (CDMP-1), is a secreted signaling molecule that participates in skeletal morphogenesis. Heterozygous mutations in GDF5, which maps to human chromosome 20, occur in individuals with autosomal dominant brachydactyly type C (BDC). Here we show that BDC is locus homogeneous by reporting a GDF5 frameshift mutation segregating with the phenotype in a family whose trait was initially thought to map to human chromosome 12. We also describe heterozygous mutations in nine additional probands/families with BDC and show nonpenetrance in a mutation carrier. Finally, we show that mutant GDF5 polypeptides containing missense mutations in their active domains do not efficiently form disulfide-linked dimers when expressed in vitro. These data support the hypothesis that BDC results from functional haploinsufficiency for GDF5.  相似文献   
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Radiosurgery for childhood intracranial arteriovenous malformations   总被引:5,自引:0,他引:5  
Levy EI  Niranjan A  Thompson TP  Scarrow AM  Kondziolka D  Flickinger JC  Lunsford LD 《Neurosurgery》2000,47(4):834-41; discussion 841-2
OBJECTIVE: The optimal management of intracranial arteriovenous malformations (AVMs) in children remains controversial. Children with intracranial AVMs present a special challenge in therapeutic decision-making because of the early recognition of their future life-long risks of hemorrhage if they are treated conservatively. The goals of radiosurgery are to achieve complete AVM obliteration and to preserve neurological function. We present long-term outcomes for a series of children treated using radiosurgery. METHODS: The findings for 53 consecutive children who underwent at least 36 months of imaging follow-up monitoring after radiosurgery were reviewed. The median age at the time of treatment was 12 years (range, 2-17 yr). Thirty-one children (58%) presented after their first intracranial hemorrhaging episodes, two (4%) after their second hemorrhaging episodes, and one (2%) after five hemorrhaging episodes. Nineteen children (36%) presented with unruptured AVMs, and a total of 25 children (47%) exhibited neurological deficits. AVMs were graded as Spetzler-Martin Grade I (2%), Grade II (23%), Grade III (36%), Grade IV (9%), or Grade VI (30%). The median AVM volume was 1.7 ml (range, 0.11-10.2 ml). The median marginal dose was 20 Gy (range, 15-25 Gy). RESULTS: Results were stratified according to AVM volumes (Group 1, < or =3 ml; Group 2, >3 ml to < or =10 ml; Group 3, >10 ml). Twenty-eight patients (80%) in Group 1 and 11 (64.7%) in Group 2 achieved complete obliteration. The only patient in Group 3 did not achieve obliteration. Complications included brainstem edema (n = 1) and transient pulmonary edema (n = 1). Four patients experienced hemorrhaging episodes, 30, 40, 84, and 96 months after radiosurgery. Multivariate logistic regression analysis demonstrated that only volume was significantly correlated with obliteration rates (P = 0.0109). CONCLUSION: Radiosurgery is safe and efficacious for selected children with AVMs. The obliteration rates and the attendant low morbidity rates suggest a primary role for stereotactic radiosurgery for pediatric AVMs.  相似文献   
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