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101.
PurposeTo compare patterns of choroidal venous drainage in eyes with pachychoroid disease to those of healthy subjects using ultra-widefield indocyanine green angiography (UWF ICGA).MethodsPatients with pachychoroid disease and healthy controls were recruited at two referral centers. UWF ICGA images were used to evaluate the proportion of the postequatorial fundus drained by major vortex vein systems in each quadrant and to study the incidence and topography of choroidal vascular hyperpermeability (CVH) and intervortex venous anastomoses. Widefield swept-source optical coherence tomography (SS-OCT) was used to evaluate choroidal thickness at the posterior pole in eyes with pachychoroid disease.ResultsFifty-two pachychoroid eyes and 26 healthy eyes were evaluated. Eyes with pachychoroid disease showed a significant within-subject variance in the proportion of the postequatorial fundus drained by each vortex vein system (range, 4.1%–48.1%; P < 0.0001) that was not seen in controls (range, 17.3%–31.7%; P = 0.11). CVH was present in all pachychoroid disease eyes and three of 26 controls. Intervortex venous anastomoses were present in 46 of 52 pachychoroid disease eyes and nine of 26 control eyes. Vortex vein systems with large drainage areas showed greater density of CVH spots. SS-OCT demonstrated asymmetric choroidal drainage in the macula of 59% of pachychoroid eyes. CVH and intervortex venous anastomoses were more prominent in areas showing maximal choroidal thickness.ConclusionsIn eyes with pachychoroid disease, imbalanced choroidal venous drainage with congestion of specific vortex vein systems may contribute to a state of choroidal venous insufficiency characterized by regional choroidal thickening, CVH and remodeling of venous drainage routes.  相似文献   
102.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析.  相似文献   
103.
Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
104.
Decrease of benzodiazepine receptors in frontal cortex of alcoholics   总被引:4,自引:0,他引:4  
G Freund  W E Ballinger 《Alcohol》1988,5(4):275-282
We hypothesize that chronic alcohol abuse results in a loss of neurons and their associated synaptic receptors. This encephalopathy may be a precursor of brain atrophy and end-stage dementia. Autopsies were performed on normal brains of 27 alcoholics (mean age 62.5) and 30 nonalcoholic matched controls (mean age 64.4) free of other brain and liver diseases. None had recently received benzodiazepine medications. Gross brain atrophy was slight and equal in both groups. Benzodiazepine receptor densities and affinities in homogenates of frontal cortex were determined using [3H]flunitrazepam. Bmax specific binding was reduced by 20% in alcoholics compared with nonalcoholic controls of comparable age and with similar death-autopsy time intervals. The affinity was slightly less in the alcoholics. Wet tissue brain protein concentrations and their yields of 50,000-g pellet proteins were similar. Aging, death-autopsy time intervals, pneumonia and chronic obstructive pulmonary disease (diseases usually associated with hypoxia) had no significant effect on brain proteins, receptor densities, or affinities. We conclude that chronic alcoholism is associated with a loss of benzodiazepine receptor densities. Alcohol abuse may affect the results of post-mortem neurochemical investigations of other diseases.  相似文献   
105.
目的:探索可早期预测严重败血症病人死亡的临床和实验室指标或系统模型。方法:对ICU连续收治的26例严重败血症病人行前瞻性观察28天,分析其死亡的相关临床和实验室指标。结果:共有14人(54%)死亡,多死于第1周内(74%)。根据循环中的细胞间粘附分子-1水平能早期预测其脏器衰竭和死亡。一些临床指标水平在死亡病人与生存病人之间差别较大,其中包括血总胆红素、pH值、红细胞压积、氧合指数、动静脉血氧差、四项SIRS指标和一些血流动力学指标等。结论:综合上述指标可以尝试建立起了一个能够早期评估病人死亡可能性的积分系统。  相似文献   
106.
107.
108.
1. Antibodies can be extracted from the brain and spinal cord of rabbits actively or passively immunized with typhoid bacilli. 2. The titers of the antibodies in the extracts of brain and cord depend upon the titer of the blood serum. In actively immunized rabbits the following numerical relationships exist between the titers of the serum and of these organ extracts: The ratio of the titer of the serum is to the titers of extract of brain and of the spinal cord about as 100 is to 0.8; the titer of the serum is to the titer of the cerebrospinal fluid as 100 is to 0.3. In passively immunized rabbits the titer of the serum is to the titer of brain and spinal-cord extract as 100 is to 0.7. 3. The antibodies recovered from the brain are not due to the presence of blood in it for perfusion of the brain does not reduce its antibody content appreciably. 4. Antibodies penetrate into the spinal fluid from the blood even in the absence of inflammation of the meninges. When the penetration is completed the following numerical relationship exists between the titer of the serum and that of the cerebrospinal fluid: 100 to 0.25. 5. The penetration into the cerebrospinal fluid of antibodies injected intravenously proceeds at a slow rate, being completed only several hours after the immune serum has been injected. The penetration of antibodies into the tissue of the brain occurs at a very rapid rate. It is completed within 15 minutes. 6. It is very unlikely that when the immune serum is injected intravenously the antibodies reach the brain tissue by way of the cerebrospinal fluid, for (1) the antibody titer of the cerebrospinal fluid is lower than that of the brain extract, and (2) antibodies penetrate faster into the tissue of the brain than into the cerebrospinal fluid.  相似文献   
109.
Background: Hippocampal sulcal cavities (HSC) have been speculated to contribute to a higher vulnerability of memory pathways and might be a possible etiological factor in transient global amnesia (TGA). Therefore, we evaluated the influence of HSC on cognitive long‐term outcome in TGA‐patients. Methods: Fourteen otherwise healthy patients with the clinical syndrome of TGA in their history underwent a high‐resolution magnetic resolution imaging and a comprehensive neuropsychological test battery. The neuropsychological control group consisted of 15 healthy subjects and was balanced for age, sex and other risk factors as well as intellectual and social status. Results: Magnetic resolution imaging and neuropsychological testing have been performed 1128 days (median) after the TGA. HSC have been detected in nine of the 14 patients and have been bilateral in eight of them. There were no differences in cognitive performance in patients with and without HSC as well as compared to healthy subjects. Even in patients with greater lesion load, only a slight visuospatial deficit was found. Conclusions: Although an increased incidence of HSCs is detected in TGA patients, cavities are not obligatorily in TGA. Moreover, even patients with hippocampal cavities achieve a full neuropsychological recovery independent of the frequency and size of the hippocampal lesions.  相似文献   
110.
Introduction: The clinical assessment of affective functioning has been slow to incorporate findings from affective neuroscience. Of particular interest in the current study is the assessment of affective word production. Method: In a series of four studies, we examined test–retest and interrater reliability for the Emotion Word Fluency Test (EWFT), basic construct validity with existing verbal fluency measures, physiological responses across verbal fluency tasks, and a novel scoring method to examine qualitative aspects of participant response sets. Results: Results demonstrated interrater and test–retest reliability values that were comparable to those of other commonly used verbal fluency tests. Construct validity was demonstrated by relations between the EWFT and other verbal fluency tests as well as through physiological evidence that performance on the EWFT is related to greater sympathetic activity than traditional verbal fluency tasks. Lastly, some of the novel scoring metrics related to two self-report measures of emotional functioning. Conclusions: Taken together, our findings provide initial support for the use of the EWFT as a measure of emotion word generation ability in young adults. This measure may prove to be useful in the assessment of affective language production in patient populations.  相似文献   
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