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1.
This work focused on the histological alterations in gill, liver and kidney of fish Colossoma macropomum exposed to different temperatures (18°C, 29°C, 35°C) with 10mg/L of herbicide Paraquat (PQ), during 21 days. The fish exhibited histopathological changes in these tissues; the most important alteration in gills was telangiectasis. Liver showed debris accumulation inside cytoplasm hepatocytes, karyolysis, karyohesis and a decrease in the size of sinusoids. Hyperplasia of melanomacrophagic centers (MMC) and an increase in basophils were observed in kidney. The lesion inducing by PQ and the damage in tissue depended of temperature exposure fish. The severity of lesions clearly differed among organs with the liver showing the most extensive damages followed in order by the kidney and gills. In PQ/18°C group it was observed the changes in the pattern of lesions, with kidney showing higher damage followed gills and liver.  相似文献   
2.
IntroductionThe ratio of cerebrospinal fluid (CSF) glucose and blood glucose is of major relevance, conducting to the diagnosis of hypoglycorrhachia, which is a sign of neuroinfection, as well as a number of neurological diseases of genetic or neoplastic etiology. Glucose in capillary sample (glucometry) is a low cost, readily available technique, as compared to venous glucose. This study aims to compare glucometry to venous glucose in the diagnosis of hypoglycorrhachia in pediatric population.MethodsProspective cross-sectional study based on data obtained from lumbar punctures in the period from February 2017 to January 2019 in a specialized pediatric institution in Colombia.Results97 patients were analyzed, aged 1 month to 17 years old, mean 7.67 years, 52 (53.61%) were female. 26 (26.8%) were diagnosed with hypoglycorrhachia. Pearson correlation coefficient for absolute venous and capillary glucose was 0.54, and 0.55 for the ratios of CSF glucose/venous glucose and CSF glucose/glucometry, which support a linear correlation between the variables in both, absolute values and ratios. Intraclass correlation coefficient was calculated for both, the venous glucose and glucometry ratios, which was 0.52, revealing a moderate agreement among the tests. Sensitivity and specificity of CSF glucose/glucometry, as compared to gold standard are 73.1% and 60.6% respectively; whereas predictive positive value (PPV) and negative predictive value (NPV), were 40.4% and 86.0%.ConclusionGlucometry cannot replace the glucose in venous sample in the diagnosis of hypoglycorrhachia in children.  相似文献   
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Activated macrophages are described as classically activated or M1 type and alternatively activated or M2 type, depending on their response to proinflammatory stimuli and the expression of genetic markers including iNOS, arginase1, Ym1, and Fizz1. Here we report that Akt kinases differentially contribute to macrophage polarization, with Akt1 ablation giving rise to an M1 and Akt2 ablation resulting in an M2 phenotype. Accordingly, Akt2(-/-) mice were more resistant to LPS-induced endotoxin shock and to dextran sulfate sodium (DSS)-induced colitis than wild-type mice, whereas Akt1(-/-) mice were more sensitive. Cell depletion and reconstitution experiments in a DSS-induced colitis model confirmed that the effect was macrophage-dependent. Gene-silencing studies showed that the M2 phenotype of Akt2(-/-) macrophages was cell autonomous. The microRNA miR-155, whose expression was repressed in naive and in LPS-stimulated Akt2(-/-) macrophages, and its target C/EBPβ appear to play a key role in this process. C/EBPβ, a hallmark of M2 macrophages that regulates Arg1, was up-regulated upon Akt2 ablation or silencing. Overexpression or silencing of miR-155 confirmed its central role in Akt isoform-dependent M1/M2 polarization of macrophages.  相似文献   
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Current knowledge concerning the molecular mechanisms of the cellular response to excitotoxic insults in neurodegenerative diseases is insufficient. Although glutamate (Glu) has been widely studied as the main excitatory neurotransmitter and principal excitotoxic agent, the neuroprotective response enacted by neurons is not yet completely understood. Some of the molecular participants have been revealed, but the signaling pathways involved in this protective response are just beginning to be identified. Here, we demonstrate in vivo that, in response to the cell damage and death induced by Glu excitotoxicity, neurons orchestrate a survival response through the extracellular signal-regulated kinase (ERK) signaling pathway by increasing ERK expression in the rat hippocampal (CA1) region, allowing increased neuronal survival. In addition, this protective response is specifically reversed by U0126, an ERK inhibitor, which promotes cell death only when it is administered together with Glu. Our findings demonstrate that the ERK signaling pathway has a neuroprotective role in the response to Glu-induced excitotoxicity in hippocampal neurons. Therefore, the ERK signaling pathway may be activated as a cellular response to excitotoxic injury to prevent damage and neural loss, representing a novel therapeutic target in the treatment of neurodegenerative diseases.  相似文献   
5.
IntroductionPalliative gastrojejunostomy is a surgical technique that allows restoration of oral intake among patients with gastric outlet obstruction (GOO) caused by unresectable neoplasms. Research suggests standard treatment for malignant GOO should be laparoscopic gastrojejunostomy (LGJ). This study presents the clinical outcomes of palliative gastrojejunostomy and compares results from LGJ and open gastrojejunostomy (OGJ) at our centre.MethodsWe performed a retrospective analysis on patients who underwent palliative gastrojejunostomy for GOO caused by unresectable neoplasms between 2008 and 2018. We included demographic variables, time to recover intestinal transit, time to recover oral intake, hospital stay, complications and global survival.ResultsA total of 39 patients underwent palliative gastrojejunostomy (20 OGJ, 19 LGJ). Patients in the LGJ group recovered oral intake and intestinal transit faster than those in the OGJ group (3 vs 5 days, p<0.05). There were no statistically significant differences in median operating time, hospital stay or postoperative complications between the two groups. No intraoperative complications occurred. The estimated global survival was 178 days, with no significant difference between the groups.ConclusionsPalliative LGJ allows earlier restoration of oral intake and does not increase morbidity or mortality. Palliative LGJ should be considered the standard treatment for these patients.  相似文献   
6.
Naegleria fowleri infects humans through the nasal mucosa causing a disease in the central nervous system known as primary amoebic meningoencephalitis (PAM). Polymorphonuclear cells (PMNs) play a critical role in the early phase of N. fowleri infection. Recently, a new biological defence mechanism called neutrophil extracellular traps (NETs) has been attracting attention. NETs are composed of nuclear DNA combined with histones and antibacterial proteins, and these structures are released from the cell to direct its antimicrobial attack. In this work, we evaluate the capacity of N. fowleri to induce the liberation of NETs by human PMN cells. Neutrophils were cocultured with unopsonized or IgG‐opsonized N. fowleri trophozoites. DNA, histone, myeloperoxidase (MPO) and neutrophil elastase (NE) were stained, and the formation of NETs was evaluated by confocal microscopy and by quantifying the levels of extracellular DNA. Our results showed N. fowleri induce the liberation of NETs including release of MPO and NE by human PMN cells as exposure interaction time is increased, but N. fowleri trophozoites evaded killing. However, when trophozoites were opsonized, they were susceptible to the neutrophils activity. Therefore, our study suggests that antibody‐mediated PMNs activation through NET formation may be crucial for antimicrobial responses against N. fowleri.  相似文献   
7.
Forty outpatients with major depressive disorder were studied with the 1 mg DST and the Afternoon Cortisol Test. No relationship was found between hypothalamic-pituitary-adrenal (HPA) axis function and Research Diagnostic Criteria subtypes of depression, with the exception of higher log post-dexamethasone cortisol levels in endogenous depressives. Patients with mood reactivity had lower cortisol values on all assessments. The data suggest that the presence of mood reactivity may be useful as a predictor of normal HPA function in depression.  相似文献   
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Aspiration of bronchial secretions is a usual technique that may have an affect on hemodynamic and respiratory parameters of the patient. Our objects has been to assess if there are changes in these parameters based on two different aspiration systems: closed (CS) or open (OS) and to also compare the times used in the process. A clinical trial was performed using the crossing over method in which aspirations were performed to the same patient with the two systems. The onset system was randomized and, after a wash-out period of 3 hours, an alternative system was established. We recorded ventilatory, gasometric (baseline and at five minutes of finishing the technique) and hemodynamic (baseline, during the procedure and at five minutes) variables. The time used in each procedure was recorded. The aspiration was always performed with preoxygenation at 100% during one minute. A total of 26 patients subjected to mechanical ventilation in the assisted/controlled way entered the study and 52 aspirations were studied. We analyzed the data with the Student's t test for paired samples and ANOVA. There were no differences in the comparisons between the different determinations for the hemodynamic and gasometric variables. In the ventilatory ones, we only found a significant increase in the respiratory frequency posterior to the OS in regards to the baseline of the same system (p = 0.016). The time used in the technique was greater for the OS (p < 0.001). It can be concluded from the results that: 1. The aspiration technique does not produce clinically important alterations in the parameters studied. 2. There are no differences between the two aspiration systems. 3. The technique with CS is faster.  相似文献   
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