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61.
In order to evaluate the clinical and endocrinological efficacy of two low-dose oral contraceptives (OC) containing 30 micrograms Ethinylestradiol (EE) and 150 micrograms Desogestrel (DG) and 75 micrograms Gestodene (GD), respectively, an open randomized study was carried out in 34 young hirsute women, matched for body mass index and age. All of them met endocrine and ultrasonic criteria for Micropolycystic Ovary Syndrome (MPCO). The participants were randomly assigned to one of two pill groups (each of 17). The serum values for Total Testosterone (TT), Free Testosterone (FT), Androstenedione (A), Dehydroepiandrosterone (DHEA), Dehydroepiandrosterone Sulphate (DHEAS), 17-Hydroxyprogesterone (17Pg), Sex Hormone Binding Globulin (SHBG), Ceruloplasmin (CP), as well as Ferriman-Gallwey Index (FGI) and Free Androgen Index (FAI) were evaluated prior to and after EE-DG and EE-GD 6 cycle treatment. A significant decrease in TT, FT, A, 17Pg, DHEA, DHEAS, FGI, FAI was observed, SHRG and CP increased significantly. There were no significant differences between the two OC. Our results seem to indicate that both OC are equipotent as far as their pharmacological profile and residual androgenic activity are concerned. Therefore, these OC may represent a highly effective and suitable alternative to the treatment of hyperandrogenism related to MPCO.  相似文献   
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To study the natural history of scoliosis in spinal muscular atrophy (SMA), 63 spinal radiographs of affected patients who attended the Muscle Clinic of Rizzoli Orthopaedic Institute between 1974 and 1988 were reviewed. All but one of the intermediate SMA patients, and all of the mild SMA patients who stopped walking had a scoliosis that ranged from 10 degrees to 165 degrees. Out of the 19 mild SMA patients still able to walk, 12 had a scoliosis ranging from 10 degrees to 45 degrees. Mean age at the onset of scoliosis was 4 years 4 months in intermediate SMA, and 9 years 10 months in mild SMA. Data on characteristics of the scoliotic curve are reported. The effectiveness of orthopaedic treatment in the prevention of scoliosis is discussed.  相似文献   
64.
Trunk posture and spinal stability   总被引:11,自引:0,他引:11  
OBJECTIVE: The influence of trunk posture on musculoskeletal stability of the spine was investigated. DESIGN: A biomechanical model was developed to evaluate the influence of posture on spinal stability. Model performance was assessed by comparing predicted muscle recruitment patterns with measured EMG activity from the trunk muscles during static lifting exertions. METHOD: An inverted double-pendulum model of the spine controlled by 12 muscle equivalents of the trunk was implemented to determine spinal load and stability. Model input included trunk posture and lifted mass, output included muscle recruitment patterns necessary to achieve stability of the spine and spinal load. EMG activity recorded from the trunk muscles of 10 subjects were recorded during static exertions in various trunk flexion and asymmetric postures to compare with model output. Stable spinal load was examined as a function of trunk flexion and asymmetry during the lifting exertions. RESULTS: Antagonistic co-contraction was necessary to achieve spinal stability, particularly in upright postures. Stable spinal load was increased in asymmetric postures as a result of antagonistic muscle recruitment, suggesting greater neuromuscular control is necessary to maintain stability in asymmetric lifting postures. As trunk flexion angle increased, stability improved but spinal load was greater. CONCLUSIONS: Results illustrate that muscle recruitment patterns are more accurately explained by stability than by equilibrium alone. Spinal stability is influenced by posture. Specifically, control of spinal stability is reduced in asymmetric postures associated with low-back disorder risk. RELEVANCE: Traditional assessment of low-back disorder risk have focussed on spinal loading. Results illustrate that postural risk factors for low-back pain may be partially attributable to stability considerations.  相似文献   
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The fructosamine test is considered clinically useful for assessing short-term integrated control of blood glucose, but there are few published data to support this hypothesis. We fractionated glycated and nonglycated proteins by affinity chromatography on phenylboronate columns and, with specific immunochemical methods, determined in the eluted fractions the following proteins, selected according to their biological half-lives and relative concentrations in serum: albumin, IgA, IgG, IgM, apolipoprotein B, haptoglobin, transferrin, alpha 1-antitrypsin, and alpha 2-macroglobulin. We found the following correlations between fructosamine (mmol/L) and, respectively, glycated albumin, IgG, and (albumin + IgG) (each in grams per liter): r = 0.901, 0.702, 0.878. IgM had the highest percentage of glycated molecules (range 11.1-37.5%, mean 22.4%), haptoglobin and alpha 1-antitrypsin the least. This result was almost independent of the proteins' molecular masses and fractional catabolic rate. Albumin evidently contributes most to results of the fructosamine test, confirming conclusions obtained in different ways by others.  相似文献   
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The wide spectrum of clonal hematopoietic disorders that fall under the broad diagnostic category of myelodysplastic syndromes (MDS) consist of a family of bone marrow malignancies – with ineffective, inadequate, and dysplastic hematopoiesis, and with an increased risk of life‐threatening infections, bleeding, and progression to acute myeloid leukemia (AML) – that are characterized by a deep heterogeneity on the clinical, biologic and prognostic level. The intrinsic complexity of this group of disorders and the frequent association with one or more comorbidities have limited for many years the number of effective treatment options available: most patients are, indeed, still managed by supportive care measures, with just a minority of them being eligible for allogeneic stem cell transplantation, which is still the only potentially curative modality. In the last two decades, the progressively better understanding of MDS biology has shown how an abnormal epigenetic modulation might play a crucial part in the pathogenesis and in the process of biologic evolution of these disorders. Moreover, pharmacological agents that target the so‐called epigenome have shown a significant clinical activity for diverse hematologic malignancies, including MDS. The aim of this review is to highlight recent developments within the context of current knowledge of MDS and its altered epigenetic regulation and to recall the experimental steps that have brought to the clinical development and application of epigenetic modifiers, such as azacytidine and decitabine, trying to explain the biologic rationale for their use in this setting.  相似文献   
70.
Among its pleiotropic actions, ghrelin modulates insulin secretion and glucose metabolism. Herein we investigated the role of ghrelin in pancreatic beta-cell proliferation and apoptosis induced by serum starvation or interferon (IFN)-gamma/TNF-alpha, whose synergism is a major cause for beta-cell destruction in type I diabetes. HIT-T15 beta-cells expressed ghrelin but not ghrelin receptor (GRLN-R), which binds acylated ghrelin (AG) only. However, both unacylated ghrelin (UAG) and AG recognized common high-affinity binding sites on these cells. Either AG or UAG stimulated cell proliferation through Galpha(s) protein and prevented serum starvation- and IFN-gamma/TNF-alpha-induced apoptosis. Antighrelin antibody enhanced apoptosis in either the presence or absence of serum but not cytokines. AG and UAG even up-regulated intracellular cAMP. Blockade of adenylyl cyclase/cAMP/protein kinase A signaling prevented the ghrelin cytoprotective effect. AG and UAG also activated phosphatidyl inositol 3-kinase (PI3K)/Akt and ERK1/2, whereas PI3K and MAPK inhibitors counteracted the ghrelin antiapoptotic effect. Furthermore, AG and UAG stimulated insulin secretion from HIT-T15 cells. In INS-1E beta-cells, which express GRLN-R, AG and UAG caused proliferation and protection against apoptosis through identical signaling pathways. Noteworthy, both peptides inhibited cytokine-induced NO increase in either HIT-T15 or INS-1E cells. Finally, they induced cell survival and protection against apoptosis in human islets of Langerhans. These expressed GRLN-R but showed also UAG and AG binding sites. Our data demonstrate that AG and UAG promote survival of both beta-cells and human islets. These effects are independent of GRLN-R, are likely mediated by AG/UAG binding sites, and involve cAMP/PKA, ERK1/2, and PI3K/Akt.  相似文献   
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