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71.
A diagnosis of perilymphatic fistula is still controversial. Recently, a case report indicated that beta-trace protein (prostaglandin D synthase) might be a potential marker for perilymphatic fluid. In this multicentre clinical case series study beta-trace protein was used as a marker for perilymphatic fluid fistula. Fifteen fluid samples were collected during diagnostic tympanoscopy. In addition, five samples were collected from patients with tympanic membrane perforation for use as as negative controls. Samples were obtained using precision glass capillaries and were analysed for beta-trace protein using laser nephelometry. The diagnosis of perilymphatic fistula was defined by the patient's history, the audiological and vestibular investigation and the findings at tympanoscopy. The cut-off level of beta-trace protein for perilymph-positive samples was chosen at 1.11 mg/l. The sensitivity and specificity were calculated using a 2 x 2 contingency table. There was no false positive result, but in two cases a false negative result was found. The specificity was 1 and the sensitivity was 0.81. The material of this first clinical study is small owing to the rarity of patients undergoing diagnostic tympanoscopy for perilymphatic fluid fistula. However, according to these preliminary results beta-trace protein might be a promising marker in the diagnosis of perilymphatic fluid fistulas.  相似文献   
72.

Purpose

To prospectively determine the feasibility and accuracy of strain‐encoded (SENC) magnetic resonance imaging (MRI) for the characterization of the right ventricular free wall (RVFW) strain and timing of contraction at 3.0 Tesla (3T) MRI.

Materials and Methods

In 12 healthy volunteers the RVFW was divided into three segments (anterior, lateral, and inferior) in each of three short‐axis (SA) slices (apical, mid, and basal) and into three segments (apical, mid, and basal) in a four‐chamber view. The study was repeated on a different day and interobserver and interstudy agreements were evaluated.

Results

Maximal systolic longitudinal strain values were highest at the apex and base, with a pronounced decrease in the medial segments (apex: –19.1% ± 1.4; mid: –17.4% ± 2; base: –19.4% ± 2.4, P < 0.001), and maximal systolic circumferential strain showed the highest values at the apex (apex: –18.1% ± 1.7; mid: –17.6% ± 1.2; base: –16.6% ± 0.9, P < 0.001). Peak systolic longitudinal and circumferential shortening occurred earliest at the apex compared to the mid‐ventricle and base. Excellent interobserver and interstudy correlation and agreement were observed.

Conclusion

The use of SENC MRI for the assessment of normal RV contraction pattern is feasible and accurate in 3T MRI. J. Magn. Reson. Imaging 2008;28:1379–1385. © 2008 Wiley‐Liss, Inc.  相似文献   
73.
Inflammatory non‐infectious diseases of the nails are not uncommon. The nail changes may look different in the same diseases, but also very much alike in various different nail disorders depending on which particular structure of the nail apparatus is involved. Of all skin diseases, psoriasis is the one with the most frequent nail involvement. The presence of many pits allows the diagnosis to be made, but salmon spots and onycholysis are also characteristic features. Lichen planus may occur isolated on the nails or in association with lesions of the skin and adjacent mucosal membranes. Longitudinal striations and loss of the nail plate shine are the most frequent features of nail lichen planus. The more severe the alopecia areata is and the younger the patient is, the more often it affects the nail, usually with a rough surface and loss of shine. Eczemas and various autoimmune dermatoses may also affect the nails but the changes are not clinically specific.  相似文献   
74.
75.
Radiation-induced cataract in astronauts and cosmonauts   总被引:4,自引:0,他引:4  
BACKGROUND: Opacification of the ocular lens is an important effect of exposure to ionizing radiation. Astronauts and cosmonauts are exposed to relatively high doses of all types of radiation in space, including high-energy particle radiation. A study was initiated to examine the lenses of the eyes of astronauts/cosmonauts to detect signs of radiation-induced cataracts. The aim of this study was to take a first step towards gaining improved, quantitative insight into the risk of radiation-induced cataract associated with long space missions. METHODS: The lenses of 21 former astronauts and cosmonauts were examined, using an upgraded Topcon SL-45 B Scheimpflug camera system. The degrees of opacification in this group of astronauts and cosmonauts were compared with the measurements in a reference group. This reference group was established by examining a cohort of 395 persons using the same Scheimpflug system. RESULTS: Initial results indicated that opacity values in most of the astronauts and cosmonauts were slightly to strongly increased in regions IV (posterior cortex) and V (posterior capsule), compared with the average opacity values for the respective age-group of the reference cohort. CONCLUSION: The aim of this study - to conduct first examinations of astronauts' and cosmonauts' ocular lenses with regard to signs of radiation-induced cataract - was successfully achieved in a total of 21 astronauts and cosmonauts using a Scheimpflug camera system. It is planned to examine a larger group of astronauts and cosmonauts in the future.  相似文献   
76.
Zusammenfassung   Die kardiovaskuläre Magnetresonanztomographie (CMR) hat sich von einem Nischenverfahren zur Darstellung angeborener Herzfehler, zur Diagnostik großer Gefäße sowie zur Untersuchung von Perikard und Tumoren zu einem breit nutzbaren, hochgradig genauen und schnellen Untersuchungsverfahren entwickelt. Neue Indikationen finden sich insbesondere im Bereich der ischämischen Herzerkrankungen, für deren Erkennung Dobutamin-Stress, Adenosin-Perfusion, Narben- und Vitalitätsdarstellung und zunehmend auch die Koronararteriendarstellung durchgeführt werden können.  相似文献   
77.
Objectives: The scope of the study was to evaluate a recent software for angiographic volume determination as compared to cardiovascular magnetic resonance imaging. Background: A new right ventricular analysis software closes a diagnostic gap in quantitative angiography. Cardiovascular magnetic resonance imaging short axis multi slice summation is a validated reference standard. Methods: Right ventricular angiograms were acquired in frontal and lateral projection in 15 pediatric and 17 adult patients. Additional angiograms were acquired in RAO30°/LAO60° projections in 10 adult patients. The tested models comprised area length with different regressions, multi-slice with different regressions, Boak, and pyramid method. Original regressions were used to calculate angiographic right ventricular volume. Right ventricular reference volumes were determined by multi-slice summation from cardiac magnetic resonance short-axis images. Results: Mean inter-observer difference was −1 ml (95% confidence: −35–34 ml) and mean intra-observer difference was 0 ml (95% confidence: −22–22 ml). There was no significant difference (4 ml, 95% confidence: −22–30 ml) between geometric calibration and calibration by a sphere. The area length and multi-slice models demonstrated the best agreement with the cardiac magnetic resonance reference. Performance was best for the Onnasch Lange models. Conclusion: The evaluated software provides acceptably accurate volume estimates for the majority of ventricles. In a few cases larger errors may occur, however. The area length and multi-slice models preferably with Onnasch Lange regressions may be recommended. Inter- and intra-observer agreement were excellent. Geometric calibration using data from DICOM header files may be used.  相似文献   
78.
The validation of a diffusion chamber comprising a donor and a receptor side separated by a cartilage membrane was undertaken according to the basic principles described by Peng et al. (1998). The study had three targets: first to evaluate the chamber as in vitro system by the examination of the diffusibility of compound through bovine cartilage samples; second the analysis of the affinity of compound (RS-130830) to cartilage; third to test the influence of two pre-incubation periods (one or three nights) of the cartilage samples. The validation of the chamber as in vitro system for the analysis of compound diffusibility and affinity to cartilage was performed using membrane slices of fresh bovine cartilage and a hydroxamic acid derivative (RS-130830) known as matrix metalloproteinase inhibitor (MMPI). The influence of the pre-incubation of cartilage was also examined. Compound concentrations in donor, receptor and membrane were determined by high performance liquid chromatography-mass spectrometry (HPLC-MS). Diffusion could be demonstrated after 6 h and finally 24 h incubation: the compound concentration in the receptor increased from 0 to 35 microM (mean) while it decreased in the donor from 200 to 144 microM (mean). We also found compound in the cartilage membrane (approximately 1.2 nmol (mean)). Pre-incubation of cartilage samples in culture buffer is suitable as a storage procedure, since the results on the donor side only were influenced significantly but not for the receptor and the cartilage affinity. Thus, the system could clearly reflect relevant properties of the tested compound with regard to its diffusibility and affinity to cartilage tissue.  相似文献   
79.
We report the first experiences with HELP apheresis as an emergency treatment for acute cardiovascular syndromes; two patients who were not eligible for lysis therapy and catheter intervention were treated with HELP apheresis instead. Both patients had a most severe, generalized atherosclerosis and reached the hospital too late for conventional measures. In both cases, the use of the apheresis dramatically improved the clinical situation to such an extent that the possibilities of this apheresis system urge further investigation.  相似文献   
80.
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