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51.
The influence of pH and the concentration of sodium chloride on the strength and selectivity of the interaction of twelve 8-substituted-2'-deoxyadenosine and sixteen 5-substituted-2'-deoxyuridine derivatives with gamma-cyclodextrin (GCD) have been studied by the spectral mapping technique (SPM). The potency values of the spectral map were regarded as indicators of the capability of antisense nucleosides and GCD to interact simultaneously taking into consideration all relevant data. It has been established that the strength of interaction is highest in acetic and lowest in alkaline solutions, and the selectivities of acidic, alkaline and salt solutions are markedly different. The length of hydrophobic alkyl substituents in antisense molecules influenced both the strength and selectivity of the interaction. The character of the base structure affected only the selectivity. 相似文献
52.
Trabulus S Apaydin S Altiparmak MR Seyahi N Sariyar M Serdengeçti K Erek E 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2003,23(Z2):127-130
This study was performed to determine risk factors associated with osteoporosis that develops after renal transplantation. Sixty-five kidney graft recipients were included in this study. They were divided into four groups according to the time since transplantation: Group 1 (< 1 year; n = 26), group 2 (1-3 years; n = 16), group 3 (3-5 years; n = 12) and group 4 (> 5 years; n = 11). These groups were matched according to probable risk factors for osteoporosis, findings of serum biochemistry, biochemical markers of bone turnover and measurements of bone mineral density. One way ANOVA test and Kruskal-Wallis test were used for statistical analysis. Osteoporosis was found in 22 recipients (33.8%). There were significant differences in recipient age, cumulative steroid dose, and episodes of acute rejection between the four groups. Increasing age, cumulative steroid dose and episodes of acute rejection were found to be risk factors for osteoporosis in our study. 相似文献
53.
Absent collateral function of the circle of Willis as risk factor for ischemic stroke 总被引:7,自引:0,他引:7
Hoksbergen AW Legemate DA Csiba L Csáti G Síró P Fülesdi B 《Cerebrovascular diseases (Basel, Switzerland)》2003,16(3):191-198
BACKGROUND: Autopsy studies show a higher prevalence of circle of Willis anomalies in brains with signs of ischemic infarction. Our goal was to examine the collateral function of the circle of Willis in ischemic stroke patients and to assess in a case-control study if a collateral deficient circle of Willis is a risk factor for ischemic stroke in patients with severe internal carotid artery (ICA) occlusive disease. METHODS: Our case-control study included 109 patients with an acute ischemic stroke in the anterior circulation and 113 patients with peripheral arterial disease and no known history of cerebral ischemia. The collateral function of the anterior and posterior communicating arteries of the circle of Willis was assessed by means of transcranial color-coded duplex ultrasonography (TCCD) and carotid compression tests. RESULTS: TCCD was successfully performed in 75 case patients (mean age 64 years, range 41-91 years) and in 100 control patients (mean age 61 years, range 35-89 years). In 26 cases and 19 controls, a >/=70% stenosis or occlusion of the ICA was found. A nonfunctional anterior collateral pathway in the circle of Willis was found in 33% of the cases and in 6% of the controls (p < 0.001). The posterior collateral pathway was nonfunctional in 57% of the cases and in 43% of the controls (p = 0.02). In patients with severe ICA occlusive disease, the odds ratios of a nonfunctional anterior and a nonfunctional posterior collateral pathway were 7.33 (95% confidence interval, CI, = 1.19-76.52) and 3.00 (95% CI = 0.77-12.04), respectively. CONCLUSIONS: Patients who suffer ischemic stroke in the anterior circulation have a higher incidence of collateral deficient circles of Willis than those with atherosclerotic vascular disease without ischemic cerebrovascular disease. The presence of a nonfunctional anterior collateral pathway in the circle of Willis in patients with severe ICA occlusive disease is strongly associated with ischemic stroke. 相似文献
54.
The pathogenesis of nasal polyposis by immunoglobulin E and interleukin-5 is completed by transforming growth factor-beta1 总被引:6,自引:0,他引:6
OBJECTIVES/HYPOTHESIS: Nasal polyps are benign mucosal protrusions into the nasal cavity of multifactorial origin and are characterized by chronic mucosal inflammation. The suggested multifactorial pathological mechanisms comprise several factors including cytokines and immunoglobulin E (IgE). The study was designed to examine the suggested roles of IgE, interleukin-5 (IL-5), and transforming growth factor-beta1 (TGF-beta1) in the pathogenesis of nasal polyposis. METHODS: Nasal polyps (n = 34) and healthy nasal mucosa samples (n = 9) were taken during routine endonasal surgeries. Immunoglobulin E (n = 13), IL-5 (n = 22), and TGF-beta1 (n = 27) concentrations were measured with enzyme-linked immunosorbent assay technique in homogenized polyp tissue and in control mucosa. Atopic and nonatopic groups were selected and compared. Histomorphological examination and immunohistochemical analysis to detect IL-5 and TGF-beta1 were performed in five specimens. RESULTS: The level of tissue-bound IgE was significantly higher in polyps compared with control specimens and in atopic compared with nonatopic polyps, but between nonatopic polyps and control specimens the difference was not significant. However, significant correlation was found between tissue and serum IgE in the complete polyp (P =.001) and atopic polyps group (P =.05). Tissue IL-5 concentration was significantly higher in polyps compared with control specimens, in which it was below the limit (15 pg/mL), and there was no difference between atopic and nonatopic polyps. In atopic polyps there was significant correlation between tissue IgE and IL-5. Transforming growth factor-beta1 concentration proved to be significantly higher in control mucosa than in polyps, with no difference between atopic and nonatopic polyps. Immunohistochemical analysis revealed numerous IL-5-positive eosinophil cells and TGF-beta1 positivity in the lamina propria of polyp samples, but none in control specimens. CONCLUSIONS: High tissue TGF-beta1 quantity in healthy nasal mucosa without its active form on the cell surface and its low quantity in polyps may reflect its essential role in the inhibitory mechanisms of nasal polyposis. Interleukin-5 plays a key role in the eosinophil recruitment and activation, and both atopic and nonatopic pathways might activate this process. The main sources of IL-5 and TGF-beta1 are the eosinophils and macrophages. Immediate hypersensitivity, besides other mechanisms, might be related to atopic polyps, but the involvement of other, local allergic mechanisms in IgE production of nonatopic polyp tissue cannot be excluded. 相似文献
55.
Kárteszi J Morava E Czakó M Gáti I Czopf J Kosztolányi G Melegh B 《Orvosi hetilap》2001,142(35):1915-1917
Kennedy disease is an adult onset neuromuscular disease characterized by slowly progressive proximal and bulbar muscle weakness. The disease associates with gynecomastia, adult onset infertility and sensory neuropathy, and caused by pathologic expansion of CAG repeats at the N-terminal region of the androgen-receptor gene at Xq11-q12. We report on a patient presenting with slowly progressive muscle weakness of the lower extremities, progressive dysartry and swallowing difficulties. The clinical symptoms were not fully specific for the disease. Moreover the family history was suggestive for an autosomal dominant trait meaning a diagnostic pitfall at the original examination. Finally the firm diagnosis of the Kennedy disease was established by a polimerase chain reaction based method. 相似文献
56.
Vascular tunnel creation to improve the effect of decompressive craniectomy in severe traumatic cerebral edema 总被引:2,自引:0,他引:2
More than million people/year die after head injury. The cause of death in 50% is the secondary brain swelling with incuneation. Today decompressive craniectomy with durotomy for traumatic brain swelling is performed as second--tier therapy at many clinics and hospitals. The literature mentions this method only as an option. The problem so far existed in the following fact: although the above mentioned method successfully diminished the ICP still despite this result, partial or total lesion occurred in the herniated part of the brain. The actual cause of these symptoms is found in the blockage of the veins and arteries, caused by shearing and compressive forces between the dural edge and brain tissue. Venous congestion induces further edema in the protruding parts of the brain, thus causing lesion by strangulated necrosis and hypoxia. The new surgical technique consists of a stellate manner durotomy and of creating a vascular tunnel by supporting pilasters made of haemostatic sponge around the main cortical veins and arteries of herniated brain. With the help of new technique the authors managed not only to reduce the intracranial pressure significantly but they could avoid further edema and vascular lesion as well. This due to the fact that with this method we assure the blood circulation and venous drainage of the herniated part of the brain. We think, that in this case despite of the initially severe status, the properly indicated combination of craniectomy, durotomy and vascular tunnel creation, could be the main factor of the surprisingly favorable outcome. 相似文献
57.
Villa S Barlocco D Cignarella G Papp GJ Baláti B Takács J Varró A Borosy A Keserû K Mátyus P 《European journal of medicinal chemistry》2001,36(6):495-506
Ambasilide, a representative of Class III antiarrhythmics, was reported to prolong the cardiac action potential duration in the dog, with little or no effect on Ca and Na currents. We synthesised a series of ambasilide analogues, having the 3,8-diazabicyclo-[3.2.1]-octane moiety instead of the 3,7-diazabicyclo-[3.3.1]-nonane present in ambasilide. The compounds were tested both in vitro extracellular electrophysiological assays and by the conventional microelectrode technique. Most of them lengthened the effective refractory period (ERP) with no change or slight increase on the impulse conduction time (ICT). Similarly some of the tested compounds lengthened the action potential duration (APD), a typical Class III feature, without exerting any significant effect on the maximal rate of depolarization, therefore apparently lacking Class I antiarrhythmic activity. 相似文献
58.
The pharyngo-cutan defect is a frequent complication of oropharynx and larynx operations. The not frequent serious actinomycotic inflammation of the neck, and in its treatment the repeated surgical incision was in the background of the defect. The authors review the possibilities of closing these defects, and they describe the method used. 相似文献
59.
Ozgüroglu M Turna H Demir G Döventas A Demirelli F Mandel NM Büyükünal E Serdengeçti S Berkarda B 《American journal of clinical oncology》1999,22(6):615-618
CA-125, a commonly used tumor marker for epithelial ovarian cancer, is a glycoprotein found in normal tissues derived from coelomic epithelia. Increased serum levels of CA-125 have also been found in nongynecologic tumors and nonmalignant diseases involving the peritoneum. A few recent studies and sporadic case reports have reported increased CA-125 levels in patients with non-Hodgkin's lymphoma (NHL). In our study, we aimed to evaluate the serum levels of CA-125 in patients with NHL and determine its potential role to show disease activity in NHL. Serum levels of CA-125 were measured in 61 patients with NHL and were found to be correlated with clinical stage, site of involvement, and disease activity. 相似文献
60.
The interaction of 20 antibiotics with the cationic surfactant cetyltrimethylammonium bromide (CTAB) was studied by charge-transfer reversed-phase chromatography carried out on impregnated alumina layers using water-methanol mixtures as eluents. The lipophilicity and specific hydrophobic surface area of antibiotics and the relative strength of their interaction with CTAB was calculated. CTAB interacted with 10 antibiotics the antibiotic--CTAB complex generally being more hydrophilic than the uncomplexed molecule. The relative strength of interaction depended considerably on the molecular structure of the antibiotics. Significant linear correlation was found between the lipophilicity of antibiotics and their capacity to interact with CTAB indicating the involvement of hydrophobic forces in the interaction. 相似文献