全文获取类型
收费全文 | 24002篇 |
免费 | 1618篇 |
国内免费 | 137篇 |
专业分类
耳鼻咽喉 | 308篇 |
儿科学 | 488篇 |
妇产科学 | 448篇 |
基础医学 | 3326篇 |
口腔科学 | 515篇 |
临床医学 | 2155篇 |
内科学 | 5646篇 |
皮肤病学 | 328篇 |
神经病学 | 2356篇 |
特种医学 | 957篇 |
外科学 | 3187篇 |
综合类 | 241篇 |
一般理论 | 48篇 |
预防医学 | 1870篇 |
眼科学 | 967篇 |
药学 | 1395篇 |
中国医学 | 35篇 |
肿瘤学 | 1487篇 |
出版年
2023年 | 111篇 |
2022年 | 246篇 |
2021年 | 570篇 |
2020年 | 324篇 |
2019年 | 465篇 |
2018年 | 584篇 |
2017年 | 430篇 |
2016年 | 483篇 |
2015年 | 531篇 |
2014年 | 778篇 |
2013年 | 1022篇 |
2012年 | 1522篇 |
2011年 | 1620篇 |
2010年 | 892篇 |
2009年 | 836篇 |
2008年 | 1423篇 |
2007年 | 1455篇 |
2006年 | 1269篇 |
2005年 | 1360篇 |
2004年 | 1206篇 |
2003年 | 1146篇 |
2002年 | 1129篇 |
2001年 | 287篇 |
2000年 | 262篇 |
1999年 | 303篇 |
1998年 | 243篇 |
1997年 | 256篇 |
1996年 | 203篇 |
1995年 | 175篇 |
1994年 | 131篇 |
1993年 | 133篇 |
1992年 | 192篇 |
1991年 | 172篇 |
1990年 | 177篇 |
1989年 | 128篇 |
1988年 | 139篇 |
1987年 | 140篇 |
1986年 | 149篇 |
1985年 | 151篇 |
1984年 | 160篇 |
1983年 | 154篇 |
1982年 | 151篇 |
1981年 | 173篇 |
1980年 | 145篇 |
1979年 | 123篇 |
1978年 | 107篇 |
1977年 | 104篇 |
1975年 | 112篇 |
1974年 | 101篇 |
1973年 | 120篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Albert J. Moreno Allan L. Parker Peter Fredericks Gottlieb L. Turnbull 《European journal of nuclear medicine and molecular imaging》1986,12(5-6):309-310
A 58-year-old man with a pectus excavatum demonstrated a photon-deficient defect within the left lobe of the liver on liver-spleen scintigraphy using Tc-99m SCOL. Computed tomography of the liver clearly revealed the abnormal defect seen on the liver-spleen scan to be due to the pectus excavatum. This case confirms the impression that these skeletal aberrations may cause false-positive hepatic defects.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense 相似文献
42.
The in vitro elution characteristics of vancomycin and tobramycin from calcium sulfate beads 总被引:1,自引:0,他引:1
Shawn M. Sanicola DPM Stephen F. Albert DPM 《The Journal of foot and ankle surgery》2005,44(2):121-124
The purpose of this study was to determine the elution characteristics of vancomycin and tobramycin when mixed with calcium sulfate to form antibiotic beads. Calcium sulfate was combined with vancomycin and tobramycin separately to form 2 types of antibiotic beads, which were packaged and labeled separately. The packaged calcium sulfate beads with vancomycin and tobramycin were then gas sterilized. The beads were placed in phosphate-buffered saline and kept at 36 degrees C for 6 weeks. Two separate series of assays were run simultaneously for both types of beads. In one assay, a bead containing vancomycin was placed in a fresh vial of phosphate buffered saline after each assay. The same was done with beads containing tobramycin. In the second series of assays, 9 vials of phosphate buffered saline each containing 1 vancomycin bead and 9 vials of phosphate buffered saline each containing 1 tobramycin bead was arranged. The phosphate-buffered saline was then assayed at predetermined times for both the vancomycin bead series and the tobramycin bead series. The amount of vancomycin and tobramycin assayed nearly equaled the calculated amount of antibiotic per bead measured before bead construction. Also, the elution of antibiotic from the calcium sulfate was complete within 72 hours. In conclusion, the construction and gas sterilization of calcium sulfate beads containing vancomycin and tobramycin does not destroy vancomycin and tobramycin. Also, the complete elution of available vancomycin and tobramycin in calcium sulfate beads occurs within 72 hours. 相似文献
43.
Albert J Finestone Michael R Jacobs John A Cacciamani 《Clinical Interventions in Aging》2007,2(4):715-718
Critical to survival is the geriatric concept, allostasis, defined as the ability to achieve stability through change. It is appropriate that allostasis is an introduction to this commentary, which may partially apply to the medical and pharmacy profession as currently constituted. 相似文献
44.
Johanna Albert Leif Kindlund Barbro Nilvér Waldemar Gożdzik 《Central European Journal of Medicine》2006,1(2):162-171
Abstract: Background: The laryngeal mask airway (LMA) can be used in general anaesthesia without neuromuscular block. The
laryngeal tube (LT) is a new airway device with similar airway features as LMA. LT is provided with a distal cuff to prevent
regurgitation. In this study we compared the LMA and LT concerning patient and user aspects.
Methods: Sixty patients with ASA (American Society of Anestesiologists) score 1–2 scheduled for minor surgery were randomized
to be ventilated either through LMA or LT. After insertion, the number of insertion attempts, and “positioning” and “airway-assessment”
was evaluated. The patients reported on “sore throat” after 30 and 60 minutes and the day after anaesthesia.
Results: Gender and mean age were equal in both groups. The first insertion attempt was successful in 25 of 28 patients randomised
to LMA and in 23 of 27 patients randomised to LT. LMA was evaluated to be easier in “positioning” whereas no difference in
“sore throat” was reported.
Conclusion: We found no difference between the LMA and the LT in terms user and patient friendliness and safety. 相似文献
45.
Rianne P Reijs Saskia G M van Mil Mariette H J A van Hall Johan B A M Arends Jacobiene W Weber Willy O Renier Albert P Aldenkamp 《Seizure》2007,16(5):438-444
INTRODUCTION: One-third of children with epilepsy are classified as having a cryptogenic localization related epilepsy (CLRE). In cohort studies CLRE is often grouped together with either symptomatic localization related epilepsy (SLRE) or idiopathic generalized epilepsy (IGE). Therefore, this categorization is not specific enough and will not lead to prognostic or treatment information. We objectified the classification differences between these categories. METHODS: A total of 114 children admitted to our epilepsy centre underwent a standardized clinical analysis, which yielded age at onset, duration of the epilepsy, seizure frequency, seizure type, percentage of interictal epileptiform activity on EEG (IEA), type of treatment, and full scale IQ. These variables are regarded the characteristics of the epilepsy, and used in a discriminant function analysis. RESULTS: IEA was found to be the only variable to distinguish between groups of epilepsy. SLRE could easily be distinguished significantly from IGE and CLRE, while the latter two did not differ significantly. Discriminant function analysis combined the variables into two functions, applicable to classify the children. By applying this statistical analysis method, the groups clinically classified as SLRE and IGE were mostly classified as SLRE (71.4%) and IGE (57.9%). However, CLRE appeared difficult to classify (49.2%), and most children were classified as either SLRE (19%) or IGE (31.7%). CONCLUSION: The current opinion that CLRE is 'probably symptomatic' cannot be confirmed in all cases in this study. It is most likely that the current CLRE population consists of both children with eventually SLRE, as well as yet to be described syndromes to be classified as idiopathic epilepsies. We emphasize the need for separate studies regarding children with 'probably symptomatic' (cryptogenic) localization related epilepsy, as this will maximally help children, caretakers and treating physicians to achieve the best possible outcome. 相似文献
46.
N S Jones R M Irving G R Ford A Balakrishnan D M Albert 《Clinical otolaryngology and allied sciences》1992,17(2):141-145
A new endoscopic method of measuring the cross-sectional area of a subglottic stenosis is presented. The method was tested against existing techniques using a model. By standardizing the distance from the objective of the endoscope to the stenotic area we were able to measure the cross-sectional area using a graduated grid held against the video screen. This technique was then compared with the standard one of estimating the diameter of a stenosis from the external diameter of the bronchoscope which can be passed through the stenosis. The methods were found to be equally accurate in measuring the lumen diameter. However, when measuring the minimum cross-sectional area, three of five observers were significantly better (P less than 0.01) using the photometric method rather than the standard method (Wilcoxon's rank sum test for paired data). The photometric technique of measuring the cross-sectional area of the subglottis is easily performed, non-traumatic, and allows a visual record to be kept. 相似文献
47.
48.
Imaging of activated microglia with PET and [11C]PK 11195 in corticobasal degeneration. 总被引:3,自引:0,他引:3
Karsten Henkel Jochen Karitzky Michaela Schmid Irina Mader Gerhard Glatting Jürgen W Unger Bernd Neumaier Albert C Ludolph Sven N Reske G Bernhard Landwehrmeyer 《Movement disorders》2004,19(7):817-821
Positron emission tomography (PET) using [(11)C]PK 11195, a ligand for peripheral benzodiazepine receptor binding sites, offers the opportunity to image activated microglia in vivo. This tool may therefore be used to display the occurrence of microglial activation in the course of neurodegeneration. A patient with the clinical diagnosis of corticobasal degeneration (CBD) and left-sided symptoms was studied using fluorodeoxyglucose (FDG) and [(11)C]PK 11195 PET. We found a marked right hemispheric hypometabolism and asymmetric microglial activation in corresponding areas of the basal ganglia and right temporal and parietal cortex. [(11)C]PK 11195 PET suggests involvement of microglial activation in the pathogenesis of CBD. 相似文献
49.
There are few records detailing the techniques and tribulations of early American surgeons who dared venture into the treacherous recess of the human orbit. The authors present a recently discovered letter written by a young woman who in 1841 underwent an orbital operation performed by the prominent New York City surgeon, Willard Parker. The letter details the patient's experiences in an era without anesthesia or antibiotics, and her subsequent development of conjunctival adhesions. 相似文献
50.
Rosen Raymond C. Kostis John B. Jekelis Albert Taska Lynn S. 《Archives of sexual behavior》1994,23(2):135-152
Antihypertensive drugs are commonly associated with adverse side effects in both clinical and laboratory studies. We investigated the sexual sequelae of several major classes of antihypertensive drugs (e.g., beta blockers, central alpha agonists, diuretics) in normal males and in hypertensive patients. We compared the effects of four widely used agents (methyldopa, propranolol, atenolol, hydrochlorothiazide-triamterene) and placebo, in a selected sample of 21 sexually dysfunctional male hypertensives, 13 of whom completed all five phases of the study. Each study drug was administered for a 1-month treatment period, followed by a 2-week, single-blind washout phase, according to a randomized, Latin square crossover design. Dependent variables for the study included a broad range of hormonal, NPT, and self-report measures of sexual response. Results indicated a lack of consistent drug effects on measures of sexual response, although more frequent sexual and nonsexual side effects were observed with methyldopa and propranolol. As in our previous studies, age was negatively correlated with both hormonal and NPT measures, whereas changes in blood pressure were not significantly related to sexual function scores. Results do not support the hypothesis that sexually dysfunctional males are at greater risk for adverse sexual sequelae when treated with centrally active agents or diuretics. 相似文献