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611.
Dan TA Eisenberg James MacKillop Meera Modi Joshua Beauchemin David Dang Stephen A Lisman J Koji Lum David S Wilson 《Behavioral and brain functions : BBF》2007,3(1):2-14
Background
Research on the genetic basis for impulsivity has revealed an array of ambiguous findings. This may be a result of limitations to self-report assessments of impulsivity. Behavioral measures that assess more narrowly defined aspects of impulsivity may clarify genetic influences. This study examined the relationship between possession of the DRD2 TaqI A and DRD4 48 bp VNTR genetic polymorphisms and performance on a behavioral measure of impulsivity, the delay discounting task (DDT), and three traditional self-report measures. 相似文献612.
桥粒芯糖蛋白1和2在不同表皮肿瘤中的表达 总被引:1,自引:0,他引:1
目的 探讨桥粒相关蛋白与皮肤肿瘤的关系,对桥粒芯糖蛋白1和2在鳞状细胞癌、日光性角化病、角化棘皮瘤、脂溢性角化病中的表达水平进行了比较研究.方法 免疫组化染色方法.结果 桥粒芯糖蛋白1和2在正常皮肤表皮全层细胞间呈现较强的染色,鳞状细胞癌组织中表达显着减弱或完全无表达,日光性角化病表皮正常区域表达正常或下调,细胞间变区域无染色,角化棘皮瘤和脂溢性角化病表皮中表达水平与正常皮肤的表达非常近似.结论 桥粒芯糖蛋白1和2在恶性皮肤癌中表达下调,可能与皮肤肿瘤的侵袭和转移有关. 相似文献
613.
614.
Objective To evaluate the value of peak time(PT) and corrected peak time(PTc) in the assessment of left ventricular long axis systolic function in patients with dilated cardiomyopathy(DCM).Methods Thirty-one DCM cases and thirty-six healthy cases were investigated using echocardiography.To obtain image of apical four-chamber view and apical two-chamber view, PT was measured by the technique of tissue motion annular displacement.The value of PTc was corrected by R-R interval.The critical value of PT and PTc was obtained by ROC curves.Results Compared with the PT of control group, the PT of DCM group at the site of septal and lateral were significantly increased ( P <0.05), but the PT at the site of anterior and inferior were no significantly increased ( P >0.05).The PTc at the four sites were significantly increased compared with control group ( P <0.05).The areas of under the ROC curve of PTc was 0.849 (95 % CI 0.699~0.929, P = 0.000), sensitivity and specificity of diagnosis cardiac dysfunction were 80.6 % and 66.7% respectively.Conclusions The PTc was significantly increased in patients with DCM.PTc was useful to evaluate left ventricular dysfunction in DCM patients. 相似文献
615.
A Osmancevic LT Nilsen K Landin-Wilhelmsen E Søyland P Abusdal Torjesen TA Hagve MS Nenseter AL Krogstad 《Journal of the European Academy of Dermatology and Venereology》2009,23(10):1133-1140
Background Climate therapy (heliotherapy) of psoriasis is an effective and natural treatment. Ultraviolet radiation (UVB) from the sun improves psoriasis and induces vitamin D3 synthesis. Objective The aim of the study was to investigate the effect of climate therapy on vitamin D3 synthesis, blood glucose, lipids and vitamin B12 in psoriasis patients. Methods Twenty Caucasian patients (6 women and 14 men; mean age, 47.2 years; range, 24–65) with moderate to severe psoriasis [mean Psoriasis Area and Severity Index (PASI) score 9.8; range, 3.8–18.8] received climate therapy at the Gran Canarias for 3 weeks. Blood samples were drawn before and after 15 days of sun exposure. In addition, the patients’ individual skin UV doses based on UV measurements were estimated. Results Sun exposure for 15 days lead to a 72.8% (± 18.0 SD) reduction in the PASI score in psoriasis patients. Although no direct correlation was observed between PASI score improvement and UVB dose, the sun exposure improved the vitamin D, lipid and carbohydrate status of the patients. The serum concentrations of 25‐hydroxyvitamin D [25(OH)D] increased from 57.2 ± 14.9 nmol/L before therapy to 104.5 ± 15.8 nmol/L (P < 0.0001) after 15 days of sun exposure; the serum levels of 1,25‐dihydroxyvitamin D [1,25(OH)2D] increased from 146.5 ± 42.0 to 182.7 ± 59.1 pmol/L (P = 0.01); the ratio of low‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol decreased from 2.4 to 1.9 (P < 0.001); and the haemoglobin A1c (HbA1c) levels decreased from 5.6 ± 1.7% to 5.1 ± 0.3% (P < 0.0001). Conclusion Climate therapy with sun exposure had a positive effect on psoriasis, vitamin D production, lipid and carbohydrate status. 相似文献
616.
Objective To evaluate the value of peak time(PT) and corrected peak time(PTc) in the assessment of left ventricular long axis systolic function in patients with dilated cardiomyopathy(DCM).Methods Thirty-one DCM cases and thirty-six healthy cases were investigated using echocardiography.To obtain image of apical four-chamber view and apical two-chamber view, PT was measured by the technique of tissue motion annular displacement.The value of PTc was corrected by R-R interval.The critical value of PT and PTc was obtained by ROC curves.Results Compared with the PT of control group, the PT of DCM group at the site of septal and lateral were significantly increased ( P <0.05), but the PT at the site of anterior and inferior were no significantly increased ( P >0.05).The PTc at the four sites were significantly increased compared with control group ( P <0.05).The areas of under the ROC curve of PTc was 0.849 (95 % CI 0.699~0.929, P = 0.000), sensitivity and specificity of diagnosis cardiac dysfunction were 80.6 % and 66.7% respectively.Conclusions The PTc was significantly increased in patients with DCM.PTc was useful to evaluate left ventricular dysfunction in DCM patients. 相似文献
617.
Neutrophil rolling, arrest, and transmigration across activated, surface-adherent platelets via sequential action of P-selectin and the beta 2-integrin CD11b/CD18 总被引:16,自引:6,他引:10
Platelets bound to thrombogenic surfaces have been shown to support activation-dependent firm adhesion of neutrophils in flow following selectin-mediated tethering and rolling. The specific receptor(s) responsible for mediating adhesion-strengthening interactions between neutrophils and platelets has not previously been identified. Furthermore, the ability of adherent platelets to support the migration of bound neutrophils has not been tested. We studied neutrophil interactions with activated, surface-adherent platelets as a model for leukocyte binding in vascular shear flow and emigration at thrombogenic sites. Our results demonstrate that the beta 2-integrin Mac-1 (CD11b/CD18) is required for both firm attachment to and transmigration of neutrophils across surface-adherent platelets. In flow assays, neutrophils from patients with leukocyte adhesion deficiency-1 (LAD-I), which lack beta 2-integrin receptors, formed P-selectin-mediated rolling interactions, but were unable to develop firm adhesion to activated platelets, in contrast to healthy neutrophils, which developed firm adhesion within 5 to 30 seconds after initiation of rolling. Furthermore, the adhesion-strengthening interaction observed for healthy neutrophils could be specifically inhibited by monoclonal antibodies (mAbs) to Mac-1, but not to lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18) or intercellular adhesion molecule-2 (ICAM-2; CD102). Further evidence for a beta 2-integrin-dependent neutrophil/platelet interaction is demonstrated by the complete inhibition of interleukin (IL)-8-induced neutrophil transmigration across platelets bound to fibronectin-coated polycarbonate filters by mAbs to Mac-1. Thus, Mac-1 is required for firm adhesion of neutrophils to activated, adherent platelets and may play an important role in promoting neutrophil accumulation on and migration across platelets deposited at sites of vascular injury. 相似文献
618.
Human primary brain tumour metabolism in vivo: a phosphorus magnetic resonance spectroscopy study 总被引:2,自引:0,他引:2
T A Cadoux-Hudson M J Blackledge B Rajagopalan D J Taylor G K Radda 《British journal of cancer》1989,60(3):430-436
Magnetic resonance spectroscopy was used to study intracellular pH and compounds which contain phosphorus in normal human brain and primary brain tumours non-invasively. In normal subjects (n = 7) intracellular pH (pHi) of the brain was 7.03 +/- 0.02 (mean +/- s.e.m.). The pHi did not vary between superficial (2 cm, majority grey matter) and deep brain (5 cm, majority white matter). The relative concentrations of phosphocreatine (PCr) and phosphomonoesters (PME) to ATP were also constant with depth. The relative concentration of phosphodiesters (PDE) increased from superficial to deep in normal brain. The astrocytomas (n = 7, grade II-IV) were significantly more alkaline (pHi = 7.08 +/- 0.03), and contained more PCr and PME, with respect to ATP, than normal brain at similar depth. The meningiomas (n = 4) were also more alkaline (pHi = 7.19 +/- 0.02) with a raised PME level but reduced PCr. The reduction in meningioma PCr may be due to the significant necrosis (greater than 20%) seen in the surgical biopsies. No significant necrosis was seen in the gliomas. Previous in vitro studies suggest that increased PME may be due to accumulation of phosphoethanolamine (PE), a phospholipid precursor. These results suggest that human primary brain tumours characteristically are more alkaline with increased PME than normal brain. 相似文献
619.
TA Farnsworth FRCP 《International journal of clinical practice》1998,52(6):445-446
SUMMARY Primary intracranial melanomas are rare and occur mainly in young adults. Originating from leptomeningeal melanoblasts and extending into the parenchyma, the tumours closely resemble meningiomas, from which they are radiologically difficult to distinguish despite progress in neuroimaging. Definitive diagnosis is usually made on histopathological examination, though confirmed only after post-mortem examination in some cases. Prolonged disease-free periods, and in rare cases long-term survival, are possible following successful total surgical excision. This case presented with typical clinical features but, at 79 years old, an unusual age. 相似文献
620.
Giant cell tumors of bone: treatment with radiation therapy 总被引:1,自引:0,他引:1
Records of 15 patients with giant cell tumor of bone treated with radiation therapy over a 35-year period were reviewed; ten patients for whom follow-up information was available constituted the study group. One patient was treated by means of orthovoltage equipment only, a second, by both orthovoltage and megavoltage equipment (cobalt 60). The remaining eight were all treated with megavoltage to doses of 40-52 Gy in 24-30 fractions. Seven patients are alive without disease, with an average survival of 192 months (range, 48-360 months). Three patients died of uncontrolled local and distant disease (average survival, 52 months; range, 23-99 months): one with metastasis in the lungs at time of treatment and two after treatment. Although incidence of lung metastasis appears high, it may be due to patient selection because chemotherapy had failed in all three. Complications from irradiation in one surviving patient required surgical closure of a dural fistula 19 years after treatment. No radiation-induced sarcomatous transformations of controlled tumors were noted. These data suggest that giant cell tumor of bone can be well controlled by radiation therapy. Megavoltage irradiation should be considered in treating local disease not easily controlled by surgery in the axial skeleton. Complications are minimal, and normal function can be preserved in the treated areas. 相似文献