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41.
Calcium-phosphate-hybridized tendon directly promotes regeneration of tendon-bone insertion 总被引:2,自引:0,他引:2
Mutsuzaki H Sakane M Nakajima H Ito A Hattori S Miyanaga Y Ochiai N Tanaka J 《Journal of biomedical materials research. Part A》2004,70(2):319-327
We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with tendons using an alternate soaking process. We characterized the deposited CaP on or in tendons and determined the healing process of anterior cruciate ligament (ACL) grafts by implanting CaP-hybridized free tendons in bone tunnels intra-articularly. Tendons to be implanted were alternately soaked 10 times in a Ca-containing solution and a PO(4)-containing solution for 30 s each. Treated tendons had ash contents threefold that of untreated tendons. Low-crystallinity apatite was found on or in treated tendons. In animal experiments, the CaP-hybridized tendon exhibited osteoclasts at the tendon-bone interface at 5 days after operation. At 2 weeks after operation, there were more osteoclasts and osteoblasts around the tendon than at 5 days after operation. Directly bonded areas were partially found between the implanted tendon and newly formed bone. The formation of a cartilage layer was partially apparent at 3 weeks after operation. The newly formed bone was observed almost around the tendon. We conclude that CaP-hybridized tendons clearly enhance the healing process of ACL grafts at the tendon-bone interface and regenerate a direct insertion-like formation of tendons similar to a normal healthy ACL insertion within 3 weeks after operation. 相似文献
42.
Influence of polymorphisms in the genes for cytokines and glutathione S-transferase omega on sporadic Alzheimer's disease 总被引:2,自引:0,他引:2
We studied promoter region polymorphisms in the interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, tumor necrosis factor, and transforming growth factor (TGF)-beta1 genes in Japanese patients with Alzheimer's disease (AD) (n = 172) and normal controls (n = 163). We also examined an association of a polymorphism located in the glutathione S-transferase omega 1 (GSTO-1) gene region with AD patients. None of these genotypes or allele frequencies showed a significant difference between AD patients and controls. We also failed to detect any difference in the disease onset between each genotype of the seven polymorphisms. Although AD patients carrying high producer alleles of TGF-beta1 and IL-1beta or TGF-beta1 and IL-6 showed a tendency for an early onset of the disease, neither of these combined effects reached a significant level after multiple comparisons. Our findings suggest that genetic polymorphisms in the cytokines and GSTO do not play a major role in Japanese AD patients. 相似文献
43.
Myopathy phenotype in transgenic mice expressing mutated PABPN1 as a model of oculopharyngeal muscular dystrophy 总被引:1,自引:2,他引:1
Hino H Araki K Uyama E Takeya M Araki M Yoshinobu K Miike K Kawazoe Y Maeda Y Uchino M Yamamura K 《Human molecular genetics》2004,13(2):181-190
Autosomal dominant oculopharyngeal muscular dystrophy (OPMD)is a late-onset disorder characterized clinically by progressiveptosis, dysphagia and limb weakness, and by unique intranuclearinclusions in the skeletal muscle fibers. The disease is causedby the expansion of a 10-alanine stretch to 1217 alanineresidues in the poly(A)-binding protein, nuclear 1 (PABPN1;PABP2). While PABPN1 is a major component of the inclusionsin OPMD, the exact cause of the disease is unknown. To elucidatethe molecular mechanism and to construct a useful model fortherapeutic trials, we have generated transgenic mice expressingthe hPABPN1. Transgenic mice lines expressing a normal hPABPN1with 10-alanine stretch did not reveal myopathic changes, whereaslines expressing high levels of expanded hPABPN1 with a 13-alaninestretch showed an apparent myopathy phenotype, especially inold age. Pathological studies in the latter mice disclosed intranuclearinclusions consisting of aggregated mutant hPABPN1 product.Furthermore, some TUNEL positive nuclei were shown around degeneratingfibers and a cluster of it in the lesion in necrotic musclefibers. Interestingly, the degree of myopathic changes was moreprominent in the eyelid and pharyngeal muscles. Further, muscleweakness in the limbs was apparent as shown by the fatigabilitytest. Nuclear inclusions seemed to develop gradually with aging,at least after 1 week of age, in model mouse muscles. We establishedthe first transgenic mouse model of OPMD by expressing mutatedPABPN1, and our model mice appear to have more dramatic alternationsin myofiber viability. * To whom correspondence should be addressed. Tel: +81 963736083; Fax: +81 963736599; Email: yamamura{at}gpo.kumamoto-u.ac.jp 相似文献
44.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
45.
Tadaaki Yokota Yoshimi Yamashita Yoshiko Okuzono Mutsuo Takahashi Shigeyoshi Fujihara Shin'ichiro Akizuki Tokuhiro Ishihara Fumiya Uchino Takako Iwata 《Pathology international》1984,34(3):663-668
A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984. 相似文献
46.
Kushiro K Zakir M Sato H Ono S Ogawa Y Meng H Zhang X Uchino Y 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,131(4):406-415
Saccular and utricular organs are essential for postural stability and gaze control. Although saccular and utricular inputs are known to terminate on vestibular neurons, few previous studies have precisely elucidated the origin of these inputs. We investigated the saccular and utricular inputs to single vestibular neurons in whole vestibular nuclei of decerebrated cats. Postsynaptic potentials were recorded from vestibular neurons after electrical stimulation of the saccular and utricular nerves. Ascending and descending axonal projections were examined by stimulating the oculomotor/trochlear nuclei and the cervical segment of the spinal cord, respectively. After each experiment, locations of recorded neurons were identified. The recorded neurons (140) were classified into vestibulo-spinal (79), vestibulo-oculo-spinal (9), and vestibulo-ocular (3) neurons based on antidromic responses; 49 other vestibular neurons were unidentified. The majority of recorded neurons were mainly located in the lateral vestibular nucleus. Most of the otolith-activated vestibular nuclei neurons seemed to participate in vestibulospinal reflexes. Of the total 140 neurons recorded, approximately one third (51) received saccular and utricular inputs (convergent neurons). The properties of these 51 convergent neurons were further investigated. Most (33/51) received excitatory postsynaptic potentials (EPSPs) after saccular and utricular nerve stimulation. These results implied that most of the convergent neurons in this study additively coded mixed information for vertical and horizontal linear acceleration. Based on the latencies of convergent neurons, we found that an early integration process for vertical and horizontal linear acceleration existed at the second-order level. 相似文献
47.
The chitosan prepared from crab tendon I: the characterization and the mechanical properties 总被引:5,自引:0,他引:5
Crystalline chitosan was prepared from crab tendon consisting mainly of chitin, including various proteins and calcium phosphates. The crab tendon has high mechanical properties due to its aligned molecular structure. Crab tendon components, i.e. proteins and calcium phosphates, were removed by deacetyl treatment using 50wt% NaOH aqueous solution at 100 degrees C, and a subsequent ethanol treatment. As judged from microscopic observations using an optical polarizer, the treated chitosan remained intact regarding its aligned molecular structure, and had a high tensile strength of 67.9+/-11.4MPa. The tensile strength was further enhanced to 235+/-30MPa by a thermal treatment at 120 degrees C, corresponding to the formation of the intermolecular hydrogen bonds. 相似文献
48.
John M. Ruiz Bert N. Uchino Timothy W. Smith 《International journal of psychophysiology》2006,60(3):274-283
Recent models hypothesize that hostility confers increased risk of CHD through weaker parasympathetic dampening of cardiovascular reactivity (CVR). We tested this possibility using the forehead cold pressor task, a common maneuver which elicits the “dive reflex” characterized by a reflexive decrease in HR presumably through cardiac-parasympathetic stimulation. Participants were initially chosen from the outer quartiles of a sample of 670 undergraduates screened using the hostility subscale of the Aggression Questionnaire ([Buss, A.H., Perry, M., 1992. The Aggression Questionnaire. Journal of Personality and Social Psychology, 63, 452-459.]). The final sample of 80 participants was evenly divided between men and women and high and low hostility. Following a 10-min baseline, participants underwent a 3-min forehead cold pressor task. The task evoked a significant HR deceleration that was mediated by PNS activation, as assessed by respiratory sinus arrhythmia (RSA). Replicating prior research, men displayed greater decrease in HR. More important, low hostiles maintained larger HR deceleration over time compared to high hostiles although the autonomic basis for this effect was unclear. The findings broaden understanding of hostility and sex-related cardiovascular functioning and support the task as a method for evoking PNS-cardiac stimulation. 相似文献
49.
T Ishihara S Akizuki S Yamanami Y Yamashita T Yokota Y Okuzono M Takahashi T Kamei F Uchino N Matsumoto 《Acta pathologica japonica》1983,33(5):943-958
A large number of foamy cells were noted in the spleens from fourteen ITP patients, and two patients who received a large amount of platelet rich plasma. Using the unlabelled immunoperoxidase method, these foamy cells were shown to contain platelet antigen. Platelets in varying stages of intracellular digestion, from intact-appearing forms to myelin-like materials, were disclosed in foamy cells. Foamy cells were experimentally induced in granulomas by subcutaneous injection of platelets with or without accompanied administration of steroid, the platelets reacted with anti-murine platelet antibody, commercialized phospholipids (PE, PC, SM, PS, and the mixture of them), and the red blood cell membrane. The foamy cells induced by the subcutaneous injection of platelets are similar to those in the spleens of ITP patients. The lipid in foamy cells is chiefly derived from the membrane phospholipid of injected platelets. Concentric myelin-like materials were also noted in the foamy cells after injection of erythrocyte membrane. The myelin-like materials in these foamy cells are similar to those appearing in macrophages following injection of PC and SM. This suggests that these phospholipids derived from cell membrane are more resistant to intracellular digestion by lysosomal enzymes. We conclude that the foamy appearance of the cordal macrophage in ITP spleens results from incomplete intracellular degradation of platelet membrane. 相似文献
50.
H Adachi T Yumoto I Takeda M Ozaki N Matsumoto T Ishihara F Uchino 《Acta pathologica japonica》1989,39(4):254-259
A study was conducted on two brothers with Jordans' anomaly. Fat-containing vacuoles were noticed in all leukocytes of the peripheral blood and cells of the myeloid series including myeloblasts, but the serum lipids showed no abnormalities. However, cells of the erythroid series, megakaryocytes and platelets did not contain these vacuoles. An increase in vacuole number was observed as the leukocytes matured. Histochemically, it was suggested that these vacuoles contained neutral fat based on staining with Sudan III and Nile blue sulfate. Ultrastructurally, these vacuoles were unassociated with lysosomes or other cell organelles. Although the etiology of Jordans' anomaly could not be clarified by this study, genetic factors may be involved. 相似文献