全文获取类型
收费全文 | 1054篇 |
免费 | 55篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 47篇 |
妇产科学 | 7篇 |
基础医学 | 83篇 |
口腔科学 | 28篇 |
临床医学 | 108篇 |
内科学 | 231篇 |
皮肤病学 | 26篇 |
神经病学 | 63篇 |
特种医学 | 186篇 |
外科学 | 111篇 |
综合类 | 41篇 |
预防医学 | 51篇 |
眼科学 | 15篇 |
药学 | 37篇 |
中国医学 | 1篇 |
肿瘤学 | 72篇 |
出版年
2023年 | 6篇 |
2022年 | 14篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 22篇 |
2018年 | 27篇 |
2017年 | 19篇 |
2016年 | 17篇 |
2015年 | 30篇 |
2014年 | 25篇 |
2013年 | 36篇 |
2012年 | 45篇 |
2011年 | 50篇 |
2010年 | 31篇 |
2009年 | 30篇 |
2008年 | 43篇 |
2007年 | 46篇 |
2006年 | 39篇 |
2005年 | 30篇 |
2004年 | 25篇 |
2003年 | 35篇 |
2002年 | 41篇 |
2001年 | 26篇 |
2000年 | 28篇 |
1999年 | 16篇 |
1998年 | 24篇 |
1997年 | 50篇 |
1996年 | 31篇 |
1995年 | 29篇 |
1994年 | 23篇 |
1993年 | 18篇 |
1992年 | 15篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 17篇 |
1987年 | 20篇 |
1986年 | 22篇 |
1985年 | 15篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1982年 | 12篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 4篇 |
1978年 | 10篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 14篇 |
1966年 | 3篇 |
排序方式: 共有1115条查询结果,搜索用时 15 毫秒
81.
WS Lee PJ McKiernan J de Ville de Goyet MS Tanner PR John 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1352-1355
A 16-y-old boy who had undergone bone marrow transplantation for relapsed acute lymphoblastic leukaemia developed liver cirrhosis and refractory ascites, which did not respond to salt restriction, diuretics and abdominal paracentesis. Liver transplantation was not feasible because of poor nutritional status, pre-existing renal dysfunction and uncertainty about the prognosis of his leukaemia. The patient underwent a successful transjugular intrahepatic portosystemic shunt (TIPS), with immediate resolution of ascites, enabling cessation of diuretics and improvement in nutritional status. At 24 mo following TIPS there has been no re-accumulation of ascites. CONCLUSION: TIPS may have a role in the management of refractory ascites secondary to liver cirrhosis in selected children. 相似文献
82.
83.
Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma. 相似文献
84.
Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available. 相似文献
85.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
86.
Monitoring for undertransfusion 总被引:1,自引:0,他引:1
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components. 相似文献
87.
Oral sumatriptan in the acute treatment of migraine and migraine recurrence in general practice 总被引:1,自引:0,他引:1
Scott RJ; Aitchison WR; Barker PR; McLaren GI 《QJM : monthly journal of the Association of Physicians》1996,89(8):613-622
We investigated the efficacy, safety and tolerability compared with placebo
of a second dose of oral sumatriptan 100 mg in 1349 general practice
patients who had already treated a moderate or severe migraine headache
with 100 mg sumatriptan 4 h earlier. Headache was relieved by the first
sumatriptan dose in about 70% of patients, but the second dose did not
produce significantly more relief than placebo, either in nonresponders or
in the group as a whole, nor did it reduce other symptoms (photophobia,
nausea, vomiting, etc,) at 8 h, or influence the incidence of headache
recurrence. The drug was well-tolerated, and a further single dose was
effective in treating recurrence after initial relief. A single 100 mg dose
of sumatriptan is an effective acute treatment for migraine. A second dose
should be reserved for treating headache recurrence.
相似文献
88.
Kejia Cai Ravi PR Nanga Lisa Lamprou Claudia Schinstine Mark Elliott Hari Hariharan Ravinder Reddy C Neill Epperson 《Neuropsychopharmacology》2012,37(13):2764-2771
Gamma-aminobutyric acid (GABA) and glutamate are implicated in numerous neuropsychiatric and substance abuse conditions, but their spectral overlap with other resonances makes them a challenge to quantify in humans. Gabapentin, marketed for the treatment of seizures and neuropathic pain, has been shown to increase in vivo GABA concentration in the brain of both rodents and humans. Gabapentin effects on glutamate are not known. We conducted a gabapentin (900 mg) challenge in healthy human subjects to confirm and explore its effects on GABA and glutamate concentrations, respectively, and to test the ability of single voxel localized proton magnetic resonance spectroscopy (1H-MRS) to reliably measure GABA and glutamate in the visual cortex at the ultra-high magnetic field of 7 Tesla. Reproducibility of GABA and glutamate measurements was determined in a comparison group without drug twice within day and 2 weeks apart. Although GABA concentration changes were small both within day (average 5.6%) and between day (average 4.8%), gabapentin administration was associated with an average increase in GABA concentration of 55.7% (6.9–91.0%). Importantly, drug-induced change in GABA levels was inversely correlated to the individual''s baseline GABA level (R2=0.72). Mean glutamate concentrations did not change significantly with or without drug administration. In conclusion, localized 1H-MRS at 7 Tesla can be successfully applied to the measurement of GABA concentration and is sensitive to acute drug-induced changes in cortical GABA. Whether baseline GABA concentrations predict clinical efficacy of gabapentin is an area worthy of exploration. 相似文献
89.
Zeina Bárzaga Arencibia Alberto López Leyva Yordanka Mejías Peña Alba Rosa González Reyes Maurilys Acosta Nápolez Demetrio Carbonell Perdomo Edita Fernández Manzano Imti Choonara 《The International journal of pharmacy practice》2012,20(6):390-394
Objective To describe access to antiepileptic drug therapy and estimate the prevalence of epilepsy in children in Camagüey Province, Cuba. Methods All the community pharmacies in the province were visited and information collected about the number of children receiving antiepileptic drugs in 2009. Availability and cost of each antiepileptic drug were determined. The prevalence of epilepsy was estimated by determining the number of children receiving antiepileptic drugs. Results There were 923 children who received a total of 977 antiepileptic drugs in Camagüey Province. The estimated prevalence of epilepsy was 5.18 per thousand children which is lower than previously reported rates in other low and lower‐middle income countries. Most of the children (871, 94%) received a single antiepileptic drug. Carbamazepine and valproate were the two most frequently prescribed antiepileptic drugs. Antiepileptic drugs were available from the local pharmacy on 76% of occasions. If the antiepileptic drug was not available from the local pharmacy, the parent had to travel to another pharmacy to obtain the medicine. Conclusions The estimated prevalence of epilepsy in children in Cuba is lower than that estimated in other lower‐middle income countries. Access to drug therapy in children with epilepsy can be achieved in lower‐middle income countries. 相似文献
90.
Holmström L de Manzano O Vollmer B Forsman L Valero-Cuevas FJ Ullén F Forssberg H 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,215(3-4):359-367
Multifinger dexterous manipulation of unstable or deformable objects requires control of both direction and magnitude of fingertip force vectors. Our aim was to study the neuroanatomical correlates of these two distinct control functions. Brain activity was measured using functional magnetic resonance imaging while 16 male subjects (age: 26-42, M = 32, SD ± 4 years) compressed four springs representing a 2 × 2 factorial design with two levels of force and instability requirements. Significant activations associated with higher instability were located bilaterally in the precentral gyri, the postcentral gyrus, and the cerebellum. In the main effect for high force, activity was found in areas located in the primary motor regions contralateral to the active hand and bilaterally in the cerebellum. An overlap in activation between the two main effects was found bilaterally in the cerebellum (lobule VI). This study not only confirms a recently described bilateral fronto-parieto-cerebellar network for manipulation of increasingly unstable objects, but critically extends our understanding by describing its differentiated modulation with both force magnitude and instability requirements. Our results, therefore, expose a previously unrecognized and context-sensitive system of brain regions that enable dexterous manipulation for different force magnitude and instability requirements of the task. 相似文献