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51.
52.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
53.
Granulocyte (PMN) concentrates collected for transfusion to septic, neutropenic patients are stored in the blood bank for various periods of time before they are given. Current methods of blood bank storage of PMN concentrates are associated with impaired in vitro PMN chemotaxis (CTX) and in vivo recovery and circulation kinetics after 24 hours of storage. This suggested the possibility that PMN may become hyperadherent during storage. To test this hypothesis, PMN concentrates were harvested and stored at both 22 and 6 degrees C and their adherence properties to relevant biologic surfaces, endothelial cell (EC) monolayers, and extracellular matrix (ECM) derived from endothelium were measured. Adherence was measured within 4 hours of collection and after 24 and 48 hours of storage. The aggregation properties of fresh and stored PMN were also studied. The adherence of fresh, unstimulated PMN to EC and ECM (31 +/- 5% and 34 +/- 4%, respectively) increased significantly after storage for 24 hours (EC = 41 +/- 8%; ECM = 43 +/- 4%) at 22 degrees C. F-Met-Leu-Phe (FMLP) stimulated the adherence of fresh PMN (EC = 37 +/- 4%; ECM = 42 +/- 4%; p less than 0.05). The adherence of PMN stored at 22 degrees C was further stimulated by FMLP (EC = 46 +/- 6%; ECM = 50 +/- 4%). PMN stored at 6 degrees C had significantly higher adherence than PMN stored at 22 degrees C, and the percentage of increase in adherence induced by FMLP was attenuated in PMN stored at 6 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
We studied clinical features potentially related to dysphagia and three
indices from a timed test of swallowing--average volume per swallow (ml),
average time (s) per swallow and swallowing capacity (ml/s)--in 181
screened healthy adults and 30 patients with motor neurone disease (MND).
In healthy adults, age, sex and height accounted for 44.3% and 55.6% of the
variance of log average volume per swallow and log swallowing capacity,
respectively. Symptoms and signs were more prevalent in the MND group and
were associated with reduced swallowing capacity and reduced average volume
per swallow; repeatability studies on these two indices in both groups
showed that the median difference between the mean of two recordings on
successive days and the mean of all recordings (6-15 over 3 days) was <
5% (maximum third quartile 12.8%, indices expressed as percent predicted
according to age and sex). Using this simple bedside test, swallowing
function can be quantified on a ratio scale and expressed as percent of
that predicted by age and sex; such information may improve the predictive
value of clinical assessment and provides a practical way of monitoring
change in patients with dysphagia.
相似文献
55.
KAZUYOSHI SUENARI M.D. YU‐FENG HU M.D. HSUAN‐MING TSAO M.D. CHING‐TAI TAI M.D. CHERN‐EN CHIANG M.D. YENN‐JIANG LIN M.D. SHIH‐LIN CHANG M.D. LI‐WEI LO M.D. TUAN TA‐CHUAN M.D. PI‐CHANG LEE M.D. NGUYEN HUU TUNG M.D. SHIH‐YU HUANG M.D. TSU‐JUEY WU M.D. SHIH‐ANN CHEN M.D. 《Journal of cardiovascular electrophysiology》2010,21(10):1114-1119
Gender Differences in Patients With AVNRT. Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender‐related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation. Methods and Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study. We evaluated the gender differences in their electrophysiological characteristics. Women had a significantly younger age of onset, higher incidence of multiple jumps, shorter AH interval, atrial effective refractory period (ERP), anterograde fast pathway ERP, anterograde slow pathway ERP, and retrograde slow pathway ERP, and longer ventricular ERP than men. The incidence of baseline ventriculoatrial dissociation was lower in women than in men. Women needed less isoproterenol/atropine to induce AVNRT. No gender differences in the radiation exposure time, procedure time, complication rate, acute success rate, or second procedure rate were noted. Both typical and atypical AVNRT were more predominant in women. In the patients with atypical AVNRT, there was no significant gender difference in incidence of baseline ventriculoatrial dissociation; however, the retrograde slow pathway ERP was significantly shorter in women than in men. Women of premenopausal age (≤50 years old) had a significantly higher incidence of anterograde multiple jumps and a retrograde jump phenomenon, and a shorter anterograde slow pathway ERP and retrograde slow pathway ERP than those of women over 50 years old. Conclusion: Gender differences in the anterograde and retrograde AV nodal electrophysiology were noted in the patients with AVNRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1114‐1119) 相似文献
56.
LI‐WEI LO M.D. SATOSHI HIGA M.D. Ph.D. YENN‐JIANG LIN M.D. SHIH‐LIN CHANG M.D. TA‐CHUAN TUAN M.D. YU‐FENG HU M.D. WEN‐CHIN TSAI M.D. HSUAN‐MING TSAO M.D. CHING‐TAI TAI M.D. SUGAKO ISHIGAKI M.D. ASUKA OYAKAWA M.D. MINETAKA MAEDA M.D. KAZUYOSHI SUENARI M.D. SHIH‐ANN CHEN M.D. 《Journal of cardiovascular electrophysiology》2010,21(6):640-648
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010) 相似文献
57.
目的:研究野茼蒿的挥发性成分。方法:用固相微萃取(solid-phase microextrations,SPME)和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用仪对野茼蒿的挥发性成分进行测定。结果:从中共鉴定出37种化学成分。含量最多的3种成分是月桂烯(61.609%)、牛儿烯D(6.481%)、α-葎草烯(6.293%)。结论:茼蒿主要挥发性成分为烯烃。 相似文献
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