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121.
Chlamydia pneumoniae uses the mannose 6-phosphate/insulin-like growth factor 2 receptor for infection of endothelial cells 下载免费PDF全文
Several mechanisms for attachment and entry of Chlamydia have been proposed. We previously determined that the major outer membrane protein of Chlamydia trachomatis is glycosylated with a high-mannose oligosaccharide, and a similar structure inhibited the attachment and infectivity of C. trachomatis in epithelial cells. Because insulin-like growth factor 2 (IGF2) was shown to enhance the infectivity of Chlamydia pneumoniae but not C. trachomatis in endothelial cells, a hapten inhibition assay was used to analyze whether the mannose 6-phosphate (M6P)/IGF2 receptor that also binds M6P could be involved in infection of endothelial cells (HMEC-1) by Chlamydia. M6P and mannose 6-phosphate-poly[N-(2-hydroxyethyl)-acrylamide] (M6P-PAA) inhibited the infectivity of C. pneumoniae AR-39, but not C. trachomatis serovar UW5 or L2, while mannan inhibited the growth of C. trachomatis, but not C. pneumoniae. Using metabolically labeled organisms incubated with cells at 4 degrees C (organisms attach but do not enter) or at 37 degrees C (organisms attach and are internalized), M6P-PAA was shown to inhibit attachment and internalization of C. pneumoniae in endothelial cells but did not inhibit attachment or internalization of C. trachomatis serovar E or L2. These findings indicate that C. pneumoniae can utilize the M6P/IGF2 receptor and that the use of this receptor for attachment and entry differs between C. pneumoniae and C. trachomatis. 相似文献
122.
Muschalik Carolin Otten Mirja Breuer Johannes von Rüden Ursula 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(11):1364-1371
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Repräsentative quantitative Surveys erheben das Geschlecht der Teilnehmenden, um geschlechtsspezifische Analysen im Hinblick... 相似文献
123.
Gabriele A. Krombach Christa Hahnen Klaus-Peter Lodemann Nils Krämer Felix Schoth Mirja Neizel Jan Boeringer Rolf W. Günther Malte Kelm Harald Kühl 《European radiology》2009,19(9):2136-2146
Gadobenate (Gd-BOPTA), injected at a dose of 0.1 mmol/kg body weight, was compared with gadopentetate (Gd-DTPA), injected
at a dose of 0.2 mmol/kg body weight, for delineation of myocardial infarction interindividually in two groups of 26 patients
each. Delayed enhancement images were assessed subjectively for image quality, and measured for regional T1 values before,
3 min after and 25 min after the injection of each contrast agent. In the 26 patients who received Gd-BOPTA, T1 values of
remote myocardium were 1,070 ± 125 ms, 358 ± 78 ms and 562 ± 108 ms before, 3 min after and 25 min after injection, respectively.
Infarcted myocardium values were 1,097 ± 148 ms, 246 ± 68 ms and 373 ± 84 ms and left ventricular blood pool 1,238 ± 95 ms,
194 ± 47 ms and 373 ± 72 ms. In the 26 patients who received Gd-DTPA, T1 values were 1,087 ± 96 ms, 325 ± 60 ms and 555 ± 108 ms
for remote myocardium; 1,134 ± 109, 210 ± 43 ms and 304 ± 57 ms for infarcted myocardium; and 1,258 ± 104 ms, 166 ± 27 ms
and 351 ± 73 ms for left ventricular blood pool. Delayed enhancement image quality showing myocardial infarction was rated
good (54%) and excellent (46%) after Gd-BOPTA, and good (58%) and excellent (42%) after Gd-DTPA (no significant differences).
A single dose of Gd-BOPTA compared with a double dose of Gd-DTPA causes similar changes of T1 values in infarcted and remote
myocardium and provides fairly similar contrast between infarcted and remote myocardium (0.64 ± 14 versus 0.71 ± 11) and slightly
higher contrast between left ventricular blood and infarcted myocardium (0.22 ± 17 versus 0.14 ± 6; p < 0.05). Administration of 0.1 mmol/kg body weight Gd-BOPTA can provide similar late enhancement images compared with the
standard 0.2 mmol/kg body weight dose of Gd-DTPA due to the higher T1 relaxivity associated with the former.
Peter Lodemann is an employee of Bracco Deutschland GmbH. 相似文献
124.
125.
Wennström L Safai-Kutti S Stockelberg D Holmberg E Palk K Varik M Viigimaa I Vaht K Luik E Everaus H Kutti J 《Acta haematologica》2011,126(3):176-185
126.
Reliable, valid and cost-effective methods for the assessment of infant sleep and sleep problems are of major importance. In this study, the first aim was to assess the agreement of an electronic diary as well as a paper diary with actigraphy for measuring infant sleep patterns in a community sample. The second aim was to assess the feasibility and acceptance of, and compliance with, the electronic diary and the paper diary. Ninety parents reported infant sleep behavior in a paper diary in their home environments for a total of 6 days, 95 in an electronic diary, within two consecutive weeks while actigraphic data were obtained simultaneously. We found moderate to good agreement between electronic diaries and actigraphy (r = 0.41-0.65, P < 0.01), and paper diaries and actigraphy (r = 0.47-0.70, P < 0.01). In addition, this study also found good agreement between both diaries and also between both diaries and actigraphy for sleep percentage over 24 h (electronic diaries and actigraphy: 54.1 ± 0.7%, 52.5 ± 0.7%, P < 0.05; paper diaries and actigraphy: 55.1 ± 0.5%, 52.2 ± 0.6%, P < 0.01) and for daytime (electronic diaries and actigraphy: 27.3 ± 0.9%, 23.5 ± 1.2%, P < 0.01; paper diaries and actigraphy: 27.3 ± 0.8%, 23.2 ± 1.0%, P < 0.01), with the exception that less daytime sleep was recorded on actigraphy than on either diary. In conclusion, the electronic diary and the paper diary are valid and well-accepted methods for the assessment of infant sleep. Parents preferred the electronic diary but, conversely, they were less compliant in completing it. 相似文献
127.
Avela K Aktan-Collan K Horelli-Kuitunen N Knuutila S Somer M 《American journal of medical genetics. Part A》2011,155(4):875-879
Recently, three children with a microduplication in 17p13 including the PAFAH1B1 gene that encodes LIS1 were reported. LIS1 overexpression has earlier been shown to affect brain development by causing migrational defects and reductions in brain volume [Bi et al., 2009]. Here, we report an additional patient with a microduplication on chromosome 17p13.1p13.3 including the PAFAH1B1 gene, that was inserted into the long arm of chromosome 4. The patient had psychomotor and growth retardation, dysmorphic features, small ventricular septal defect (VSD), and immunoglobulin abnormality. Only subtle abnormalities in brain MRI scan were seen. Interestingly, the facial features of our patient closely resemble those previously reported in 17p trisomy patients. 相似文献
128.
Tenhunen M Rauhala E Virkkala J Polo O Saastamoinen A Himanen SL 《Sleep & breathing》2011,15(4):737-746
Introduction
Measuring breathing effort during sleep with an oesophageal pressure sensor remains technically challenging and has not become routine practice. The aim of the present work was to investigate whether increased thoracic pressure during sleep can be detected with the Emfit movement sensor. Experimental data suggest that increased respiratory efforts with the intrathoracic pressure variation induce high-frequency spikes in the Emfit signal, but this has not been systematically examined. 相似文献129.
130.
Jehna M Langkammer C Wallner-Blazek M Neuper C Loitfelder M Ropele S Fuchs S Khalil M Pluta-Fuerst A Fazekas F Enzinger C 《Brain imaging and behavior》2011,5(4):241-251
The ability to recognize emotional facial expressions is crucial to adequate social behavior. Previous studies have suggested deficits in emotion recognition in multiple sclerosis (MS). These deficits were accompanied by several confounders including cognitive or visual impairments, disease duration, and depression. In our study we used functional MRI (fMRI) to test for potential early adaptive changes in only mildly disabled MS patients performing an emotion recognition task including the facial expressions of the emotions anger, fear and disgust. Fifteen relapsing-remitting MS patients with a median Expanded Disability Status Scale (EDSS) score of 2 (range: 0-3.5) and 15 healthy controls (HC) matched for age, gender, and education underwent behavioral (BERT: behavioral emotion recognition test; BRB-N: Brief Repeatable Battery for neuropsychological tests, WCST: Wisconsin Card Sorting Test) and clinical assessments (BDI: Beck Depression Inventory). Conventional MRI at 3.0T served to assess whole-brain volume, white matter, gray matter, cerebrospinal fluid, and T2-lesion load; during fMRI, participants were confronted with neutral, scrambled, angry, disgusted, and fearful faces, and houses. In the absence of differences in cognitive performance and in the ability to accurately recognize distinct emotional facial expressions, MS patients demonstrated excess fMRI activations during facial recognition compared to HC. These differences concerned the posterior cingulate cortex (PCC) and precuneus for anger and disgust contrasted to neutral faces, and the occipital fusiform gyri and the anterior CC for neutral faces versus houses. This study provides first evidence for excess activation during processing of higher order visual stimuli of emotional content in the absence of emotional, visual or cognitive behavior abnormalities already in earlier stages of MS. 相似文献