全文获取类型
收费全文 | 2369篇 |
免费 | 122篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 89篇 |
妇产科学 | 69篇 |
基础医学 | 318篇 |
口腔科学 | 46篇 |
临床医学 | 227篇 |
内科学 | 668篇 |
皮肤病学 | 65篇 |
神经病学 | 117篇 |
特种医学 | 312篇 |
外科学 | 224篇 |
综合类 | 25篇 |
预防医学 | 140篇 |
眼科学 | 17篇 |
药学 | 109篇 |
中国医学 | 7篇 |
肿瘤学 | 93篇 |
出版年
2023年 | 10篇 |
2022年 | 21篇 |
2021年 | 55篇 |
2020年 | 27篇 |
2019年 | 54篇 |
2018年 | 64篇 |
2017年 | 29篇 |
2016年 | 35篇 |
2015年 | 58篇 |
2014年 | 50篇 |
2013年 | 102篇 |
2012年 | 104篇 |
2011年 | 111篇 |
2010年 | 92篇 |
2009年 | 102篇 |
2008年 | 98篇 |
2007年 | 114篇 |
2006年 | 76篇 |
2005年 | 85篇 |
2004年 | 52篇 |
2003年 | 69篇 |
2002年 | 49篇 |
2001年 | 50篇 |
2000年 | 58篇 |
1999年 | 53篇 |
1998年 | 75篇 |
1997年 | 91篇 |
1996年 | 107篇 |
1995年 | 66篇 |
1994年 | 61篇 |
1993年 | 56篇 |
1992年 | 35篇 |
1991年 | 27篇 |
1990年 | 33篇 |
1989年 | 47篇 |
1988年 | 46篇 |
1987年 | 44篇 |
1986年 | 51篇 |
1985年 | 47篇 |
1984年 | 11篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 9篇 |
1980年 | 15篇 |
1979年 | 8篇 |
1978年 | 14篇 |
1977年 | 11篇 |
1976年 | 17篇 |
1975年 | 13篇 |
1974年 | 8篇 |
排序方式: 共有2549条查询结果,搜索用时 406 毫秒
61.
62.
Vega Jovani Estíbaliz Loza M. Jesús García de Yébenes Miguel Ángel Descalzo Juan Manuel Barrio Loreto Carmona César Hernández-García 《Reumatología clinica》2012,8(3):114-119
ObjectiveOur objective was to describe the variability in the management of spondyloarthritis (SA) in Spain in terms of healthcare resources and their use.MethodsA review of 1168 medical files of patients seen in randomly selected Spanish hospital rheumatology departments. We analyzed demographic variables and variables related to the consumption of health resources.ResultsThe total number of visits to rheumatology were 5,908 with a rate of 254 visits/100 patient-years. The total number of visits to rheumatology specialty nurses was 775, with a rate of 39 visits/100 patient-years, and there were 446 hospitalizations, representing a rate of 22 per 100 patient-years. The number of admissions due to SA was 89, with a rate of 18 admissions/100 patient-years. Total visits to other specialists was 4,307 with a rate of 200/100 patient-years. The total number of orthopedic surgeries was 41, which leads to a rate of 1.8 surgeries/100 patient-years.ConclusionsThe data regarding visits to the rheumatologist and prosthetic surgery of patients with in Spain is similar to most studies published in our environment, however, other aspects concerning the use of health resources are different compared to other countries. This data may help to understand and improve organizational aspects of management of SA in Spanish hospitals. 相似文献
63.
64.
J.J. Peña E. Mateo E. Martín J. Llagunes P. Carmona L. Blasco 《Revista espa?ola de anestesiología y reanimación》2013,60(3):142-148
IntroductionPostoperative bleeding is common complication, affecting up to 20% of patients, after cardiac bypass surgery. Fibrinolysis is one of the causes of this excessive bleeding, and for this reason the use of tranexamic acid is recommended. The problem with using this is that there are numerous guidelines and differences in the dose to be administered. Our aim was to evaluate whether there were any differences in postoperative bleeding and morbidity after cardiac surgery with the administering of different tranexamic acid doses in three university hospitals.Material and methodsA retrospective, multicentre cohort study was conducted. A total of 146 patients who were subjected to elective cardiac bypass surgery according to the anaesthetic-surgical protocol of each hospital were included in the study. The clinical histories were reviewed, and they were divided into two groups according to the tranexamic acid dose: Group A (high doses), initial dose of 20 mg/kg and continuous infusion of 4 mg/kg/hour until closure of the sternotomy. A further 100 mg was added to prime the bypass machine. Group B (low doses), initial dose of 10 mg/kg followed by a continuous infusion of 2 mg/kg/hour until closure of the sternotomy. A further 50 mg was added to prime the bypass machine. Variables, such as age, sex, weight, height, type of surgical procedure (valvular, coronary or mixed), haematocrit, INR, and preoperative platelet count, time and temperature of the bypass machine, and haematocrit on sternum closure, were recorded. Among the post-operative variables collected were: debit due to drainage at 6, 12 and 24 hours after surgery, number and type of blood products transfused in the first 24 hours, need for further surgery due to haemorrhage, CVA, TIA, or a new acute myocardial infarction, convulsions, and mortality.ResultsThe incidence of increased bleeding (patients in the 90 percentile) was higher in Group B at all the study evaluation times (P<.05). The incidence of further surgery due to bleeding, and the need for transfusion of ≥3 units of packed red cells was lower in Group A (5.56%) than in Group B (13.89%). There were no significant differences in the requirements for blood products transfusions between the groups. As regards associated morbidity, there was one isolated case of convulsion and a perioperative AMI in another case in Group A, and three cases of perioperative AMI in Group B.ConclusionsElevated doses of tranexamic acid in cardiac bypass surgery appear to significantly reduce bleeding in the first hours after surgery compared to low doses. However, this decrease did not lead to a reduction in the needs for blood products. 相似文献
65.
66.
Jefferson AL Carmona H Gifford KA Lambe S Byerly LK Cantwell NG Tripodis Y Karlawish J 《The American journal of geriatric psychiatry》2012,20(10):878-886
OBJECTIVE:: To determine whether individuals with mild cognitive impairment (MCI) differ from cognitively normal (NC) elders on a risk assessment task and whether participants and their study partners evaluate risk and benefit similarly. DESIGN:: Cross-sectional. SETTING:: University medical setting. PARTICIPANTS:: Seventy-nine participants (NC, n = 40; MCI, n = 39), age 60-90 years (73 ± 7 years; 53% women), and 64 study partners (NC, n = 36; MCI, n = 28), age 38-84 years (68 ± 10 years; 67% women). MEASUREMENTS:: Participants and study partners completed a risk assessment task that involved ranking from least to most risk four hypothetical vignettes for memory loss research (brain autopsy, blood draw, oral medication, neurosurgery). Participants also completed decisional capacity for research and neuropsychological protocols. RESULTS:: MCI participants' risk rankings differed from NC risk rankings (p <0.001) with MCI participants ranking brain autopsy higher and an oral medication trial lower. Demographic, decisional capacity, and neuropsychological variables could not explain MCI participant performances. Participants and their study partners had comparable risk assessment performance (p = 1.0). MCI study partners performed similar to their MCI participant counterparts but were different from NC study partners (p = 0.002; i.e., ranking autopsy higher and oral medication lower). CONCLUSION:: Findings suggest that individuals with MCI assess risk differently than NC peers by overestimating the risk (or underestimating the benefit) of brain autopsy and underestimating the risk (or overestimating the benefit) of oral medication. Study partners display a similar pattern. These observations may be secondary to MCI participants' (and their study partners') personal connection to the potential benefits of an experimental medication for memory loss. 相似文献
67.
Fernando Pea Benito Ordaz Hugo Balleza‐Tapia Ramn Bernal‐Pedraza Abraham Mrquez‐Ramos Liliana Carmona‐Aparicio Magda Giordano 《Hippocampus》2010,20(1):78-96
Early cognitive deficit characteristic of early Alzheimer's disease seems to be produced by the soluble forms of β‐amyloid protein. Such cognitive deficit correlates with neuronal network dysfunction that is reflected as alterations in the electroencephalogram of both Alzheimer patients and transgenic murine models of such disease. Correspondingly, recent studies have demonstrated that chronic exposure to βAP affects hippocampal oscillatory properties. However, it is still unclear if such neuronal network dysfunction results from a direct action of βAP on the hippocampal circuit or it is secondary to the chronic presence of the protein in the brain. Therefore, we aimed to explore the effect of acute exposure to βAP25–35 on hippocampal network activity both in vitro and in vivo, as well as on intrinsic and synaptic properties of hippocampal neurons. We found that βAP25–35, reversibly, affects spontaneous hippocampal population activity in vitro. Such effect is not produced by the inverse sequence βAP35–25 and is reproduced by the full‐length peptide βAP1–42. Correspondingly βAP25–35, but not the inverse sequence βAP35–25, reduces theta‐like activity recorded from the hippocampus in vivo. The βAP25–35‐induced disruption in hippocampal network activity correlates with a reduction in spontaneous neuronal activity and synaptic transmission, as well as with an inhibition in the subthreshold oscillations produced by pyramidal neurons in vitro. Finally, we studied the involvement of Fyn‐kinase on the βAP25–35‐induced disruption in hippocampal network activity in vitro. Interestingly, we found that such phenomenon is not observed in slices obtained from Fyn‐knockout mice. In conclusion, our data suggest that βAP acutely affects proper hippocampal function through a Fyn‐dependent mechanism. We propose that such alteration might be related to the cognitive impairment observed, at least, during the early phases of Alzheimer's disease. © 2009 Wiley‐Liss, Inc. 相似文献
68.
We have investigated the effects of mechanical elution of neutrophils from nylon-wool fiber (NWF) using the scanning electron microscope and biochemical analysis of elution fractions. We have determined that mechanical removal of neutrophils from nylon-wool fiber disrupts neutrophils adherent to nylon-wool fiber and augments release of granules, release of peripheral cytoplasmic fragments, and release of lactic dehydrogenase, a soluble cytoplasmic enzyme. Mechanical shearing of the adherent cell, and not adherence per se, causes the fragmentation. The extent of fragmentation is proportional to the NWF surface area available to neutrophils and is maximal at the temperature for optimal adherence and spreading. Agents that decrease cell spreading (n-ethylmaleimide and cold) diminish fragmentation. Cytochalasin B, an agent that destabilizes the neutrophil cortex, increases fragmentation. Fragmentation may be an important contributing cause of the abnormal morphology, function, and in vivo survival of nylon-wool-fiber procured human neutrophils. The prevention of fragmentation would appear to be necessary to insure the procurement of optimally functioning cells. Elution of NWF-adherent neutrophils in the cold might be a practical way to diminish neutrophil damage during clinical filtration leukapheresis. 相似文献
69.
Carmona L Hernández-García C Vadillo C Pato E Balsa A González-Alvaro I Belmonte MA Tena X Sanmartí R;EMECAR Study Group 《The Journal of rheumatology》2003,30(7):1436-1439
OBJECTIVE: To quantify the risk of tuberculosis (TB) in an unselected sample of patients with rheumatoid arthritis (RA) compared to the risk in the general population. METHODS: The incidence of TB in the general population of Spain was obtained from the National Network of Epidemiological Surveillance reports. The incidence of TB was ascertained from a cohort of 788 patients with RA selected randomly from the registries of 34 participating centers throughout Spain. A patient was considered a TB case only if information about disease symptoms, microorganism identification, and TB treatment were confirmed in the clinical records. The relative risk of TB in RA was calculated by dividing the standardized mean incidence of TB from 1990 to 2000 in the RA cohort by the mean incidence of TB in Spain during the same years. RESULTS: The mean incidence of TB in the general population of Spain from 1990 to 2000 was 23 cases per 100,000. Seven cases of TB were identified in the RA cohort, yielding a mean annual incidence (1990-2000) of 134/100,000 patients. The incidence risk ratio of pulmonary TB in patients with RA compared to the general population is 3.68 (95% CI 2.36-5.92). CONCLUSION: We found a 4-fold increased risk of TB infection in patients diagnosed with RA. These results might help to interpret the magnitude of the problem attributable to the introduction of new therapies in RA. 相似文献
70.
OBJECTIVE: To evaluate the validity, responsiveness, and predictive value of power Doppler ultrasonography (PDUS) monitoring of response to tumor necrosis factor (TNF) blocking agents in rheumatoid arthritis (RA). METHODS: Three hundred sixty-seven RA patients were prospectively recruited at 25 Spanish centers; complete clinical, laboratory, and PDUS data were obtained on 278 patients. The patients underwent clinical, laboratory, and PDUS assessment at baseline and after 1, 3, 6, and 12 months of anti-TNF treatment, and radiographic assessment of the hands and feet at baseline and 12 months. The Disease Activity Score in 28 joints (DAS28) was recorded at each visit. PDUS examination included 86 intraarticular and periarticular sites in 28 joints. US synovial fluid (SF), synovial hypertrophy (SH), and PD signal were scored in all synovial sites. US count and index for SF, SH, and PD signal were obtained. Sensitivity to change of the PDUS variables was assessed by estimating the smallest detectable difference (SDD) from the intraobserver variability. RESULTS: A significant parallel improvement in DAS28 and PDUS parameters was found at followup assessment (P < 0.0005 for within-subject between-visit changes). The SDD for PDUS parameters was lower than the mean changes throughout followup. Time-integrated values of US joint count for PD signal and rheumatoid factor (RF) showed predictive value in relation to progression of radiographic erosion (R = 0.64), and time-integrated values of US joint count for PD signal, RF, and erythrocyte sedimentation rate were predictors of progression of the total radiographic score (R = 0.59). CONCLUSION: These findings indicate that PDUS is a valid method for monitoring response to anti-TNF therapy in RA; results obtained by PDUS are reproducible and sensitive to change. PDUS findings may have predictive value in relation to radiologic outcome. 相似文献