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1.
The relationship between panic attacks and chemical dependencies 总被引:1,自引:0,他引:1
The purposes of the present study were to (a) determine the prevalence and characteristics of panic attacks in an alcohol/drug abuse inpatient population, (b) compare patients who reported experiencing panic attacks to patients who have never experienced a panic attack on various self-report measures of psychopathology and on ratings completed by Caregivers, and (c) to examine differences within groups of panickers. One hundred forty-four patients completed the questionnaires over a 17 week period. Over 50% of the patients reported experiencing one or more attacks in the three weeks prior to testing. These panickers scored higher than non-panickers on various measures of psychopathology. Over 83% of panickers reported using alcohol to self-medicate their panic attacks with almost 72% of them believing this procedure to be effective for preventing or reducing panic attacks. Male panickers differed from female panickers on several measures as did panickers who reported their panic attacks began before the alcohol abuse compared to those who did not believe this. The mean history of panic attacks was 103.4 months while the mean history of alcohol abuse was 134.6 months. 相似文献
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Staphylococcus aureus aconitase inactivation unexpectedly inhibits post-exponential-phase growth and enhances stationary-phase survival 下载免费PDF全文
Somerville GA Chaussee MS Morgan CI Fitzgerald JR Dorward DW Reitzer LJ Musser JM 《Infection and immunity》2002,70(11):6373-6382
Staphylococcus aureus preferentially catabolizes glucose, generating pyruvate, which is subsequently oxidized to acetate under aerobic growth conditions. Catabolite repression of the tricarboxylic acid (TCA) cycle results in the accumulation of acetate. TCA cycle derepression coincides with exit from the exponential growth phase, the onset of acetate catabolism, and the maximal expression of secreted virulence factors. These data suggest that carbon and energy for post-exponential-phase growth and virulence factor production are derived from the catabolism of acetate mediated by the TCA cycle. To test this hypothesis, the aconitase gene was genetically inactivated in a human isolate of S. aureus, and the effects on physiology, morphology, virulence factor production, virulence for mice, and stationary-phase survival were examined. TCA cycle inactivation prevented the post-exponential growth phase catabolism of acetate, resulting in premature entry into the stationary phase. This phenotype was accompanied by a significant reduction in the production of several virulence factors and alteration in host-pathogen interaction. Unexpectedly, aconitase inactivation enhanced stationary-phase survival relative to the wild-type strain. Aconitase is an iron-sulfur cluster-containing enzyme that is highly susceptible to oxidative inactivation. We speculate that reversible loss of the iron-sulfur cluster in wild-type organisms is a survival strategy used to circumvent oxidative stress induced during host-pathogen interactions. Taken together, these data demonstrate the importance of the TCA cycle in the life cycle of this medically important pathogen. 相似文献
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The presence of checkpoint mechanisms which are able to recognize damaged
chromatin and thereafter to prevent exit from metaphase I has been
investigated in giant mouse oocytes produced by fusion of a normal
metaphase I oocyte with an equivalent oocyte with damaged chromatin. The
presence of damaged chromatin did not prevent the onset of anaphase I in
both sets of chromatin in the fused cells. Interestingly, fused or unfused
cells containing only damaged chromatin failed to enter anaphase and
persisted instead in a metaphase-like state. These results demonstrate the
fragility of checkpoint controls in mammalian female germ cells.
相似文献
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Karvandi Elika Hanrahan John Gerrard Khan Danyal Zaman Boloux Pierre-Marc Bremner Fion Cabrilo Ivan Dorward Neil Grieve Joan Jackson Sue Jimenez Glenda Serrano Inma Nowak Victoria Anne Kolias Angelos Baldeweg Stephanie E. Marcus Hani Joseph 《Pituitary》2022,25(4):673-683
Pituitary - Pituitary adenomas affect patients’ quality-of-life (QoL) across several domains, with long-term implications even following gross-total resection or disease remission. While... 相似文献
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Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL- 3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines. 相似文献
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Huan Wee Chan Ronit Pressler Christopher Uff Roxanna Gunny Kelly St Piers Helen Cross Jeffrey Bamber Neil Dorward William Harkness Aabir Chakraborty 《Epilepsia》2014,55(4):e30-e33
Focal symptomatic epilepsy is the most common form of epilepsy that can often be cured with surgery. A small proportion of patients with focal symptomatic epilepsy do not have identifiable lesions on magnetic resonance imaging (MRI). The most common pathology in this group is type II focal cortical dysplasia (FCD), which is a subtype of malformative brain lesion associated with medication‐resistant epilepsy. We present a patient with MRI‐negative focal symptomatic epilepsy who underwent invasive electrode recordings. At the time of surgery, a novel ultrasound‐based technique called ShearWave Elastography (SWE) was performed. A 0.5 cc lesion was demonstrated on SWE but was absent on B‐mode ultrasound and 3‐T MRI. Electroencephalography (EEG), positron emission tomography (PET), and magnetoencephalography (MEG) scans demonstrated an abnormality in the right frontal region. On the basis of this finding, a depth electrode was implanted into the lesion. Surgical resection and histology confirmed the lesion to be type IIb FCD. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here . 相似文献