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101.
A 53-year-old woman, nonsmoking patient, with a history of surgically corrected anomalous origin of the right coronary artery from the pulmonary artery 17 years prior to admission, presented to our department complaining of mild, left-sided exertional chest pain for the past 3 months. She underwent a computed tomography examination of the heart and coronary angiography revealing postsurgical changes to the coronary vasculature and severe stenosis of the left circumflex artery, which was successfully treated by percutaneous stent implantation. 相似文献
102.
Eva Gunde Miloslav Kopecek Lukas Propper Cyril Höschl Martin Alda Tomas Hajek 《Journal of psychiatric research》2011,45(1):76-82
Background
White matter hyperintensities (WMHs) are among the most replicated neuroimaging findings in bipolar disorder (BD). It is not clear whether these lesions are an artifact of comorbid conditions, or whether they are directly associated with the disorder, or even represent biological risk factor for BD.Methods
To test whether WMHs meet criteria for an endophenotype of BD, we conducted a high-risk design study and recruited 35 affected, 44 unaffected relatives of bipolar probands (age range 15-30 years), matched by age and sex with 49 healthy controls without any personal or family history of psychiatric disorders. The presence of WMHs was determined from Fluid Attenuated Inversion Recovery (FLAIR) scans acquired on a 1.5 Tesla scanner using a validated semi-quantitative scale.Results
We found mostly low grade WMHs in all groups. The proportion of WMH-positive subjects was comparable between the unaffected high-risk, affected familial and control groups.Conclusion
White matter hyperintensities did not meet criteria for an endophenotype of BD. Bipolar disorder in young subjects without comorbid conditions was not associated with increased rate of WMHs. 相似文献103.
Which McMaster egg counting technique is the most reliable? 总被引:1,自引:0,他引:1
Vadlejch J Petrtýl M Zaichenko I Cadková Z Jankovská I Langrová I Moravec M 《Parasitology research》2011,109(5):1387-1394
This study focuses on the comparison of three selected modifications of the McMaster counting technique, namely the McMaster
method modified by Wetzel (W) and Zajíček (Z), as well as the concentration McMaster technique according to Roepstorff and
Nansen (R&N). These modifications differ in the weights of faeces examined (W, 2 g/Z, 1 g/R&N, 4 g), flotation solutions (W,
NaCl/Z, MgSO4 + Na2S2O3/R&N, NaCl + glucose), centrifugation (W, none/Z, 2,000 RPM for 2 min and 2,000 RPM for 1 min/R&N, 1,200 RPM for 5 min), number
of McMaster chambers investigated (W, 3/Z, 2/R&N, 2), and multiplication factors used (W, 67/Z, 33/R&N, 20). To investigate
the sensitivity and reliability of these methods, nematode eggs (Teladorsagia circumcincta) were used. Parasite elements are distributed through negative binomial distribution in naturally infected host faeces, and
the number of parasite elements in a given amount of faeces sample is unknown to man. Therefore, we decided to prepare the
exact number of eggs which were added to the parasite negative faeces; the faecal sample was then investigated. From this
perspective, this is the first time a comparison of the McMaster methods has been so accurately investigated. This approach
allows us to evaluate the real sensitivity and reliability of the tested method. As the findings of this study indicate, the
highest sensitivity and reliability were obtained using the Roepstorff and Nansen modification. This McMaster modification
is able to detect 20 eggs per sample (in 70% of samples). Concentrations of 200 and 500 eggs can be found in almost 100% of
samples. Moreover, this method is simple, cheap and fast. For these reasons, we can recommend this method for routine veterinary
practice. 相似文献
104.
Hajek T Cullis J Novak T Kopecek M Höschl C Blagdon R O'Donovan C Bauer M Young LT Macqueen G Alda M 《Bipolar disorders》2012,14(3):261-270
Hajek T, Cullis J, Novak T, Kopecek M, Höschl C, Blagdon R, O’Donovan C, Bauer M, Young L T, MacQueen G, Alda M. Hippocampal volumes in bipolar disorders: opposing effects of illness burden and lithium treatment. Bipolar Disord 2012: 14: 261–270. © 2012 The Authors. Journal compilation © 2012 John Wiley & Sons A/S. Objective: Hippocampal volume decrease associated with illness burden is among the most replicated findings in unipolar depression. The absence of hippocampal volume changes in most studies of individuals with bipolar disorder (BD) may reflect neuroprotective effects of lithium (Li). Methods: We recruited 17 BD patients from specialized Li clinics, with at least two years of regularly monitored Li treatment (Li group), and compared them to 12 BD participants with < 3 months of lifetime Li exposure and no Li treatment within two years prior to the scanning (non‐Li group) and 11 healthy controls. All BD patients had at least 10 years of illness and five episodes. We also recruited 13 Li‐naïve, young BD participants (15–30 years of age) and 18 sex‐ and age‐matched healthy controls. We compared hippocampal volumes obtained from 1.5‐T magnetic resonance imaging (MRI) scans using optimized voxel‐based morphometry with small volume correction. Results: The non‐Li group had smaller left hippocampal volumes than controls (corrected p < 0.05), with a trend for lower volumes than the Li group (corrected p < 0.1), which did not differ from controls. Young, Li‐naïve BD patients close to the typical age of onset had comparable hippocampal volumes to controls. Conclusions: Whereas patients with limited lifetime Li exposure had significantly lower hippocampal volumes than controls, patients with comparable illness burden, but with over two years of Li treatment, or young Li‐naïve BD patients, showed hippocampal volumes comparable to controls. These results provide indirect support for neuroprotective effects of Li and negative effects of illness burden on hippocampal volumes in bipolar disorders. 相似文献
105.
Background: Smaller hippocampal volumes relative to controls are among the most replicated neuroimaging findings in individuals with unipolar but not bipolar depression. Preserved hippocampal volumes in most studies of participants with bipolar disorder may reflect potential neuroprotective effects of lithium (Li). Methods: To investigate hippocampal volumes in patients with bipolar disorder while controlling for Li exposure, we performed a meta-analysis of neuroimaging studies that subdivided patients based on the presence or absence of current Li treatment. To achieve the best coverage of literature, we categorized studies based on whether all or a majority, or whether no or a minority of patients were treated with Li. Hippocampal volumes were compared by combining standardized differences between means (Cohen d) from individual studies using random-effects models. Results: Overall, we analyzed data from 101 patients with bipolar disorder in the Li group, 245 patients in the non-Li group and 456 control participants from 16 studies. Both the left and right hippocampal volumes were significantly larger in the Li group than in controls (Cohen d = 0.53, 95% confidence interval [CI] 0.18 to 0.88; Cohen d = 0.51, 95% CI 0.21 to 0.81, respectively) or the non-Li group (Cohen d = 0.93, 95% CI 0.56 to 1.31; Cohen d = 1.07, 95% CI 0.70 to 1.45, respectively), which had smaller left and right hippocampal volumes than the control group (Cohen d = -0.36, 95% CI -0.55 to -0.17; Cohen d = -0.38, 95% CI -0.63 to -0.13, respectively). There was no evidence of publication bias. Limitations: Missing information about the illness burden or lifetime exposure to Li and polypharmacy in some studies may have contributed to statistical heterogeneity in some analyses. Conclusion: When exposure to Li was minimized, patients with bipolar disorder showed smaller hippocampal volumes than controls or Li-treated patients. Our findings provide indirect support for the negative effects of bipolar disorder on hippocampal volumes and are consistent with the putative neuroprotective effects of Li. The preserved hippocampal volumes among patients with bipolar disorder in most individual studies and all previous meta-analyses may have been related to the inclusion of Li-treated participants. 相似文献
106.
Though consisting of early and late components, the evoked potential preceding a voluntary movement (Bereitschaftspotential — BP) is often considered as a unitary phenomenon. By analyzing intracerebrally recorded BP we attempted to demonstrate that the components are electrophysiological correlates of separate operations. The BPs recorded in 42 epilepsy surgery candidates (28 men, 14 women; aged from 18 to 49 years) during self-paced clenching movements of the hand opposite to the explored hemisphere were investigated in the study. Microdeep intracerebral 5 to15-contact electrodes were used. The averaged curves were calculated from approximately 30 trials in each case. All the records were taken with a binaural reference. The total number of explored brain regions was 235; the event-related premovement potentials were observed in 121 of them. Three types of premovement responses were observed: (i) the BP with both components; (ii) the BP with the early component only; and (iii) the BP with the late component only. The generators of the early one-component BP were demonstrated in two frontal cortical areas (precentral and middle frontal gyri) and in the parietal area known to be involved in action planning and decision making (precuneus). Some structures generating the early one-component BP were activated during movement; the others were without motor responsiveness. The results suggest a separate elaboration of functional task items in some and their integration in other brain structures, and the existence of volitional mechanisms of different hierarchical character. 相似文献
107.
Jaroslava Pribylova Klara Krausova Ingrid Kocourkova Pavel Rossmann Klara Klimesova Miloslav Kverka Helena Tlaskalova-Hogenova 《Journal of clinical immunology》2012,32(6):1372-1380
Purpose
Human colostrum and milk provide a newborn with immunomodulatory components, ensuring protection and proper development of the immune system. Secretory IgA antibodies in colostrum represent the first line of defence against harmful substances, but their potential spectra of reactivity with autoantigens remains unclear. Here, we characterised the repertoire of natural sectretory IgA autoantibodies in colostrum of healthy mothers.Methods
The human colostrum samples from 39 healthy mothers were analyzed for autoantibodies by indirect immunofluorescence, dot blots, immunoblots and ELISA.Results
We found that there is high diversity in reactivities of colostral IgA antibodies to autoantigens among individual samples. Using tissue sections and biochips commonly used for autoimmunity testing, we found that most samples reacted with monkey ovary (79.3 %), monkey pancreatic tissue (78.6 %), human HEp-2 cells (69 %) and monkey adrenal gland (69.0 %), fewer samples reacted with monkey liver tissue (47.2 %), rat stomach (42.9 %), monkey testicular tissue (41.4 %), monkey salivary gland (39.3 %), rat kidney (32.1 %) and monkey cerebellar tissue (17.9 %). At the protein level, we detected reactivity of IgA with 21 out of 25 (auto) antigens. The majority of the samples reacted with the pyruvate dehydrogenase complex, E3 ubiquitin ligase, cytosolic liver antigen, promyelocytic leukemia protein and nuclear pore glycoprotein-210. Using ELISA, we found reactivity of colostral IgA antibodies against examined extractable nuclear antigens, double stranded DNA, phospholipids and neutrophil cytoplasm.Conclusions
The broad spectrum of polyreactive natural autoantibodies present in human colostrum may contribute to proper development of mucosal immune system of the breastfed infant. 相似文献108.
Neurons in the rodent midline thalamic paraventricular nucleus (PVT) receive inputs from brain stem and hypothalamic sites known to participate in sleep-wake and circadian rhythms. To evaluate possible diurnal changes in their excitability, we used patch-clamp techniques to record and examine the properties of neurons in anterior PVT (aPVT) in coronal rat brain slices prepared at zeitgeber time (ZT) 2-6 vs. ZT 14-18 and recorded at ZT 8.4 ± 0.2 (day) vs. ZT 21.2 ± 0.2 (night), the subjective quiet vs. aroused states, respectively. Compared with neurons recorded during the day, neurons from the night period were significantly more depolarized and exhibited a lower membrane conductance that in part reflected loss of a potassium-mediated conductance. Furthermore, these neurons were also significantly more active, with tonic and burst firing patterns. Neurons from each ZT period were assessed for amplitudes of two conductances known to contribute to bursting behavior, i.e., low-threshold-activated Ca(2+) currents (I(T)) and hyperpolarization-activated cation currents (I(h)). Data revealed that amplitudes of both I(T) and I(h) were significantly larger during the night period. In addition, biopsy samples from the night period revealed a significant increase in mRNA for Ca(v)3.1 and Ca(v)3.3 low-threshold Ca(2+) channel subtypes. Neurons recorded from the night period also displayed a comparative enhancement in spontaneous bursting at membrane potentials of approximately -60 mV and in burst firing consequent to hyperpolarization-induced low-threshold currents and depolarization-induced current pulses. These novel in vitro observations reveal that midline thalamic neurons undergo diurnal changes in their I(T), I(h), and undefined potassium conductances. The underlying mechanisms remain to be characterized. 相似文献
109.
Background
Transformed phenotypes are common to cell lines derived from various cancers. Proteome profiling is a valuable tool that may reveal uncharacteristic cell phenotypes in transformed cells. Changes in expression of glutathione S-transferases (GSTs) and other proteins interacting with glutathione (GSH) in model cell lines could be of particular interest. 相似文献110.