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81.
In the last few years, the sudden outbreak of COVID-19 caused by SARS-CoV-2 proved the crucial importance of understanding how emerging viruses work and proliferate, in order to avoid the repetition of such a dramatic sanitary situation with unprecedented social and economic costs. West Nile Virus is a mosquito-borne pathogen that can spread to humans and induce severe neurological problems. This RNA virus caused recent remarkable outbreaks, notably in Europe, highlighting the need to investigate the molecular mechanisms of its infection process in order to design and propose efficient antivirals. Here, we resort to all-atom Molecular Dynamics simulations to characterize the structure of the 5-untranslated region of the West Nile Virus genome and its specific recognition by the human innate immune system via oligoadenylate synthetase. Our simulations allowed us to map the interaction network between the viral RNA and the host protein, which drives its specific recognition and triggers the host immune response. These results may provide fundamental knowledge that can assist further antivirals’ design, including therapeutic RNA strategies.  相似文献   
82.
Interleukin (IL)-8 production by human polymorphonuclear leukocytes (PMNL) to Cryptococcus neoformans is related to complement activation. Generation of the bioactive fragments C3a and C5a is responsible for IL-8 release. IL-8 production was analyzed in response to C. neoformans by PMNL from persons with early- and late-stage (>400 and <200 CD4 cells/mm3, respectively) human immunodeficiency virus (HIV) infection who were at high risk for cryptococcosis. IL-8 release by PMNL from persons with early-stage infection and from healthy donors was similar; however, PMNL from persons with late-stage HIV infection had significantly impaired IL-8 production, which correlated with reduced IL-8 response to C3a and C5a proteins and decreased CD88 expression. Addition of murine monoclonal antibody (MAb) 18B7 promoted phagocytosis and restored IL-8 release consistent with integrity of FcgammaRIII. These results provide evidence for a selective defect in CD88 expression on PMNL from persons with late-stage HIV infection. However, Fcgamma receptor expression in PMNL appears to be intact and allows MAb to glucuronoxylomannan to positively influence PMNL function.  相似文献   
83.
To induce a specific response in primary resting T cells, two signals must be provided by antigen-presenting cells (APC). The first antigen-specific signal is mediated by formation of the T cell receptor major histocompatibility complex molecule ternary complexes. The second signal is delivered by interaction of either B7-1 or B7-2 expressed by APC with CD28 or CTLA-4 on T cells. In this study, we examined the modulation of B7-1 and B7-2 molecules on human monocytes exposed to encapsulated or acapsular Cryptococcus neoformans or Candida albicans. In our experimental system, C. albicans or acapsular C. neoformans are able to induce B7-1 expression while the encapsulated yeast is a poor stimulator. A modest increase of B7-2 expression was also observed after monocyte treatment with acapsular C. neoformans or C. albicans, while the encapsulated yeast was ineffective in inducing B7-2 molecules. Kinetic analysis showed the maximum expression of B7-1 after 24 to 48 h. Addition of the opsonic IgG1 mAb 2H1 to monocytes and C. neoformans significantly increased B7-1, but not B7-2, expression. The contribution of B7-1 and B7-2 co-stimulatory (CS) molecules to cryptococcal-specific T cell activation was analyzed and a substantial inhibition of T cell proliferation was observed. In this study we provide the first demonstration of fungal interference in the regulation of CS molecules. Our results suggest a potential mechanism for poor inflammatory responses observed in C. neoformans infections.  相似文献   
84.
This study reports the clinical use of a bioactive bone graft material, PerioGlas, in the treatment of dental extraction sites before dental implant placement, to effect bone regeneration and to give early fixation to the implant.PerioGlas, granules, ranging from 90 to 710 mm, are implanted after tooth extraction in three patients; after 6 months bone biopsies were performed in the site of the glass implantation and observed under Electron Scanning Microscopy.All the granules showed a biodegradation involving precipitation of calcium phosphate that worked as a scaffold for osteoblasts colonization. All cases examined showed the bioactivity of PerioGlas granules resulting in new bone formation and biodegradation of the glass. After a two-year clinical follow-up all the implants were successfully loaded and appeared stable.  相似文献   
85.
Periodontal disease is a widespread disorder comprising gingivitis, a mild early gum inflammation, and periodontitis, a more severe multifactorial inflammatory disease that, if left untreated, can lead to the gradual destruction of the tooth-supporting apparatus. To date, effective etiopathogenetic models fully explaining the clinical features of periodontal disease are not available. Obviously, a better understanding of periodontal disease could facilitate its diagnosis and improve its treatment. The purpose of this study was to employ a proteomic approach to analyze the gingival crevicular fluid (GCF) of patients with severe periodontitis, in search of potential biomarkers. GCF samples, collected from both periodontally healthy sites (H-GCF) and the periodontal pocket (D-GCF), were subjected to a comparison analysis using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). A total of 26 significantly different proteins, 14 up-regulated and 12 down-regulated in D-GCF vs. H-GCF, were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The main expressed proteins were inflammatory molecules, immune responders, and host enzymes. Most of these proteins were functionally connected using the STRING analysis database. Once validated in a large scale-study, these proteins could represent a cluster of promising biomarkers capable of making a valuable contribution for a better assessment of periodontitis.  相似文献   
86.
BackgroundThe prognostic role of lymph nodes metastasis in pancreatic neuroendocrine tumours is unclear.MethodsRetrospective study of 53 patients who underwent a curative standard resection for pancreatic neuroendocrine tumours. The endpoint was to define the role of the lymph nodes ratio in recurrence after curative surgery. The following data were considered as possible factors for predicting the risk of recurrence: gender, age, presence of symptoms, hormonal status, site of tumours, type of resection, size of the tumours, radical resection, pathological T, N and M stage, the Ki67 index, the number of lymph nodes harvested, the number of metastatic lymph nodes and the lymph node ratio. Recurrence rate and time of recurrence were evaluated.ResultsTwelve (26.4%) patients developed a recurrence with a median time of 42.8 (1–305) months. At multivariate analysis, the only factors related to recurrence were: size of lesions (HR 1.1, C.I. 95% 1.0–1.1, P = 0.011), Ki67 ≥ 5% (HR 3.6, C.I. 95% 1.3–10, P = 0.014) and LNR > 0.07 (HR 5.2, C.I. 95% 1.1–25, P = 0.045).ConclusionsOur study confirmed that the lymph nodes ratio played an important role in the recurrence rate and suggested that a low number of metastatic lymph nodes reduced the disease free survival.  相似文献   
87.
OBJECTIVE: To investigate the effect of highly active antiretroviral treatment (HAART) on antifungal and secretory functions of polymorphonuclear leukocytes (PMNL) from HIV-infected patients with high viral load. DESIGN: Antifungal activity, oxygen-dependent mechanisms and interleukin (IL)-12 secretion were evaluated in PMNL from HIV-infected patients before and 3 months after commencing HAART. METHODS: PMNL antifungal activity was evaluated by effects on fungal colony-forming units. Superoxide anion (O2-) production was determined by superoxide dismutase reduction and IL-12 was determined by enzyme-linked immunosorbent assay in supernatant fluids of PMNL cultured for 18 h. RESULTS: PMNL from HIV-infected patients showed dysregulation of antimicrobial and secretory functions. A selective defect in antimicrobial activity against encapsulated Cryptococcus neoformans correlated with baseline O2- overproduction, which drastically decreased upon microbial stimulation. Similarly, constitutive secretion of IL-12 was blocked by exposure to microbial products. PMNL analysed after 3 months of HAART showed restoration of antimicrobial activity against encapsulated C. neoformans, reduction in O2- formation by unstimulated cells and restoration of oxidative burst after appropriate stimulation, and reduction of IL-12 hypersecretion. CONCLUSIONS: PMNL from HIV-infected patients with high viral load have impaired function; HAART normalizes antimicrobial and secretory activities. The effects of HAART on innate immunity provide new prospects for reduction of HAART-mediated opportunistic infections.  相似文献   
88.
A linkage and association analysis was made on 14 Italian families with recurrent migraine. We analyzed five chromosomal regions surrounding the candidate genes 5HT1D (1p36.3–34.3), 5HT1B (6q13), 5HT2A (13q14–21), 5HT transporter (17q11.2–12), CACNLB1 (17q11.2–22) and FHM (19p13), using 29 DNA polymorphic markers. All two-point lod scores were negative, and the x2 sib-pair analyses were not significant, thus indicating the probable exclusion of these regions as sites of migraine genes in our population.This work was supported by MURST (40%) and CNR grant 2785 e 96.03122.CT04  相似文献   
89.
We report the clinical and genetic study of a Leber's Hereditary Optic Neuropathy (LHON) patient of North African origin harboring the 14484/ND6 mutation of mtDNA. For over a year we followed the ophthalmological course of this 24-year-old male with LHON treated with idebenone and vitamin B12. Serum lactate after effort was evaluated before, during and after therapy. Muscle biopsy was obtained for morphological study. Homo/heteroplasmy of 14484/ND6 mutation was studied in different tissues. Recovery of visual acuity was documented 6 months after onset and 3 months after therapy was established. Baseline serum lactate was elevated but normalized after 3.5 months of therapy. Muscle biopsy demonstrated only a few fibers with a slightly increased subsarcolemmal SDH activity. Genetic analysis showed homoplasmic 14484/ND6 mutation in all tissues investigated. The clinical phenotype of LHON/14484 in this patient closely resembles that commonly found in European patients. Even if LHON/14484 patients are reported to have a better prognosis for visual recovery, it is possible that the evolution of visual recovery in this patient could have been influenced by therapy as suggested by changes in serum lactate levels. Bioenergetic impairment of skeletal muscle was documented by lactate levels and muscle morphology. The 14484/ND6 mutation behaves as a primary mutation regardless of mtDNA population-specific backgrounds.  相似文献   
90.
There is a well‐established link between inflammation and cancer of various organs, but little data are available on inflammation‐associated markers of diagnostic and prognostic clinical utility in pulmonary malignancy. Blood samples were prospectively collected from 75 resectable lung cancer patients before surgery and in a cohort of 1,358 high‐risk subjects. Serum levels of long pentraxin 3 (PTX3) were determined by high‐sensitivity ELISA. PTX3 immunostaining was evaluated by immunohistochemistry in cancer tissue. Serum PTX3 levels in the high‐risk population were not predictive of developing subsequent lung cancer or any other malignancy; however, serum PTX3 values in patients with lung cancer were significantly higher compared with cancer‐free heavy smokers. With a cutoff of 4.5 ng/ml, specificity was 0.80, sensitivity 0.69, positive predictive value 0.15 and negative predictive value 0.98. The receiver operating curve (ROC) for serum PTX3 had an area under the curve (AUC) of 83.52%. Preoperative serum PTX3 levels in lung cancer patients did not correlate with patient outcome, but high interstitial expression of PTX3 in resected tumor specimens was a significant independent prognostic factor associated with shorter survival (p < 0.001). These results support the potential of serum PTX3 as a lung cancer biomarker in high‐risk subjects. Furthermore, PTX3 immunohistochemistry findings support the role of local inflammatory mechanisms in determining clinical outcome and suggest that local expression of PTX3 may be of prognostic utility in lung cancer patients.  相似文献   
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