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121.
目前临床检验中的固相化学法主要是多层膜法(Multiple Layer-Film),它集当代化学、光学、酶学、化学计量和计算机技术于一体,并已作为定量分析法达到常规湿化学法的测定水平。由于其具有准确度高、精密度高;标本量少;不需配制试剂操作简便、快速,可随时随地进行.无废液产生等优点,更适用于实验动物特别是小动物的体内生化成份测定。本项研究目的在于应用囿相化学法的优点以新西兰大耳兔为实验动物模型对兔血清中的ALT、AST、GLU、TB、BUN和Ca^2 进行分析测定,并应用临床化学分析法的选择和评价原理,在重复性实验、稀释实验、回收实验和方法比较实验等方面进行丁固相化学法对实验动物血清中生化成分测定的可行性实验探讨。  相似文献   
122.
A new approach to the study of ocular chromatic aberrations   总被引:2,自引:0,他引:2  
We measured the ocular wavefront aberration at six different visible wavelengths (between 450 and 650 nm) in three subjects, using a spatially resolved refractometer. In this technique, the angular deviation of light rays entering the pupil at different locations is measured with respect to a target viewed through a centered pupil. Fits of the data at each wavelength to Zernike polynomials were used to estimate the change of defocus with wavelength (longitudinal chromatic aberration, LCA) and the wavelength-dependence of the ocular aberrations. Measured LCA was in good agreement with the literature. In most cases the wavefront aberration increased slightly with wavelength. The angular deviations from the reference stimulus measured using a magenta filter allowed us to estimate the achromatic axis and both optical and perceived transverse chromatic aberration (TCA), (including the effect of aberrations and Stiles-Crawford effect). The amount of TCA varied markedly across subjects, and between eyes of the same subject. Finally, we used the results from these experiments to compute the image quality of the eye in polychromatic light.  相似文献   
123.
人眼眩光失能测定及其临床意义   总被引:1,自引:0,他引:1  
目的:观察国产仪器测定眩光失能的性能与规律,并讨论其临床意义。方法:采用MGT—1多功能视觉眩光测试仪(海军医学研究所研制),按规定方法操作。测定正常人30名56眼(矫正视力全部≥1.0,晶体透明,无其他明显眼病),晶体混浊患者15人27眼。测定目标亮度及眩光亮度设置为中—中及弱—中两档分别模拟白天及夜间眩光失能。结果:中—中状态下,眩光失能值正常人均值为9.22%(全距0~31),低于晶体混浊者(24.05%,全距9~67),两者差异显著。正常眼在弱—中状态眩光失能值较中—中状态明显(均值20.12%,全距0~56)。不同频率条件对正常及晶体混浊眼眩光失能的影响不同,低频及中频较高频区的影响明显。结论:作为视功能评论指标,眩光失能检查是一种实用方法。在眼科临床及人体工效学上具有重要的意义。  相似文献   
124.
Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270°. Mean IOP showed statistical differences in two periods between days 3–13 and 45–60 — Mann-Whitney U test — with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717 - Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the sclieral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery.  相似文献   
125.
During the placement of an artificial lens the ophthalmic surgeon must be guaranteed an immobile operation site and so-called soft eye. Based on our experience with more than 1000 lens implantation operations in the Rotterdam Eye Hospital over the past three years, the following conclusions can be drawn: The pharmacological agents available to the anaesthetist are sufficient for providing optimal conditions under general anaesthesia for lens implantation techniques by the eye surgeon. Hypotensive techniques are not regarded as being appropriate because of the inherent risks involved. Classical neuroleptic techniques are best avoided in the elderly. Controlled ventilation is preferable in order to avoid the deleterious side effects of hypercarbia. Constant vigilance on the part of the anaesthetist during the operation is a very important sine qua non for a tranquil course both during the anaesthetic and in the post-operative period. The routine administration of antiemetic agents after a lens implantation operation is advisable this holds true also for prevention of the Central Anticholinergic Syndrome by means of physostigmine, in patients who have received inhalation anaesthetics, particularly enflurane or, flunitrazepam.  相似文献   
126.
This study identifies brain regions participating in the execution of eye movements for voluntary positive accommodation (VPA) during open-loop vergence conditions. Neuronal activity was estimated by measurement of changes in regional cerebral blood flow (rCBF) with positron emission tomography and 15O-water. Thirteen naive volunteers viewed a checkerboard pattern with their dominant right eye, while a lens interrupted the line of gaze during alternate 1.5 s intervals. Three counterbalanced tasks required central fixation and viewing of a stationary checkerboard pattern: (i) through a 0.0 diopter (D) lens; (ii) through a -5.0-D lens while avoiding volitional accommodation and permitting blur; and (iii) through a -5. 0-D lens while maintaining maximal focus. The latter required large-amplitude, high-frequency VPA. As an additional control, seven of the subjects viewed passively a digitally blurred checkerboard through a 0.0-D lens as above. Optometric measurements confirmed normal visual acuity and ability to perform the focusing task (VPA). Large-amplitude saccadic eye movements, verified absent by electro-oculography, were inhibited by central fixation. Image averaging across subjects demonstrated multifocal changes in rCBF during VPA: striate and extrastriate visual cortices; superior temporal cortices; and cerebellar cortex and vermis. Decreases in rCBF occurred in the lateral intraparietal area, prefrontal and frontal and/or supplementary eye fields. Analysis of regions of interest in the visual cortex showed systematic and appropriate task dependence of rCBF. Activations may reflect sensorimotor processing along the reflex arc of the accommodation system, while deactivations may indicate inhibition of systems participating in visual search.  相似文献   
127.
Paradoxical inward rib cage movement in children is quantified by the labored breathing index (LBI) on the respiratory inductive plethysmography. Labored breathing index during rapid eye movement sleep (REMS) in 59 children without obvious sleep disordered breathing (SDB) declined with age, and decreased to the mature low level at 35 months of age. The LBI was also found to reflect well the severity of SDB. Paradoxical inward rib cage movement, which was quantified by LBI, is concluded to be an important finding in diagnosing SDB in child patients.  相似文献   
128.
In order to detect rapid eye movements (REM) automatically, the Discrete Wavelet Transform was applied to each 8-s segment of electrooculogram (EOG) data for 30 min of 8 h of normal sleep. The Haar function was used as an analysing wavelet because this function is similar to the REM waveform. By shifting the phase of the analysing wavelet by pi/4 of the function, 96% of REM could be detected. The artifacts caused by body movements could be detected simultaneously by this method. Computing time required for the detection of REM was only 11 s for 30 min EOG data.  相似文献   
129.
复方左氧氟沙星滴眼液的研制及临床应用   总被引:5,自引:2,他引:5  
张雷  林艳  李中华  梁毅  陈涌江 《中国药房》2003,14(6):341-343
目的 :研究复方左氧氟沙星滴眼液的制备及质量控制方法 ,并观察其临床疗效。方法 :以左氧氟沙星为主药配伍地塞米松磷酸钠 ,选择磷酸盐作为缓冲剂 ,依地酸二钠作为稳定剂 ,采用紫外分光光度法测定左氧氟沙星的含量。结果 :制剂稳定 ,左氧氟沙星在2~6μg/ml范围内线性关系良好 ;C=26 1780A—1 0838(r=0 9997) ;平均回收率为100 34 % ,RSD=0 44%(n=5)。结论 :制备工艺简单 ,质控方法可靠 ,疗效良好  相似文献   
130.
目的:建立双波长分光光度法测定盐酸环丙沙星滴眼液中盐酸环丙沙星的含量。方法:采用双波长分光光度法,盐酸环丙沙星的测定波长为277nm,参比波长为234.7nm。结果:盐酸环丙沙星的平均回收率为99.81%(RSD=0.94%,R=0.9999)。结论:本法快速,简便,结果准确。  相似文献   
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