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271.
Background/aimsInflammatory mediators contribute to the impairment of vasculogenesis by reducing endothelial progenitor cells (EPCs) mobilization in atherosclerotic vasculopathy.We tested the hypothesis that administration of an oxygen/ozone mixture (IMT) might counteract this pathophysiological mechanism and enhance limb tissue perfusion in patients with critical limb ischemia (CLI).MethodsRandomized patients with rest pain or ischemic ulcers and transcutaneous oxygen tension (TcPO2) <40 mmHg and/or toe pressure <50 mmHg received placebo (n = 74) or a non-specific immunomodulation therapy (IMT) (n = 77), autologous blood exposed to oxygen/ozone gas mixture by intragluteal injection, on day 1, 2, 7, and once a week thereafter for at least 22 weeks. Patients were evaluated for changes in TcPO2, levels of circulating EPCs (CD34/KDR-positive cells) and inflammation (tumor necrosis factor-α—TNF-α).ResultsTcPO2 and CD34/CD133-positive cells increased at 22 weeks in IMT group (P < 0.01) whereas no changes were observed in placebo group. TNF-α levels decreased at 6 months in IMT group (P < 0.001) whereas no changes were observed in placebo group. There was a strong positive correlation between CD34/KDR-positive cells and TcPO2 (r = 0.56, P < 0.01). Moreover, there was an inverse correlation between CD34/KDR-positive cells and TNF-α (r = ?0.51, P < 0.01).ConclusionsIntramuscular injection of IMT may improve wound healing and limb salvage in patients with CLI.  相似文献   
272.
The structures of the four N-linked glycans from the prototype chlorovirus PBCV-1 major capsid protein do not resemble any other glycans in the three domains of life. All known chloroviruses and antigenic variants (or mutants) share a unique conserved central glycan core consisting of five sugars, except for antigenic mutant virus P1L6, which has four of the five sugars. A combination of genetic and structural analyses indicates that the protein coded by PBCV-1 gene a111/114r, conserved in all chloroviruses, is a glycosyltransferase with three putative domains of approximately 300 amino acids each. Here, in addition to in silico sequence analysis and protein modeling, we measured the hydrolytic activity of protein A111/114R. The results suggest that domain 1 is a galactosyltransferase, domain 2 is a xylosyltransferase and domain 3 is a fucosyltransferase. Thus, A111/114R is the protein likely responsible for the attachment of three of the five conserved residues of the core region of this complex glycan, and, if biochemically corroborated, it would be the second three-domain protein coded by PBCV-1 that is involved in glycan synthesis. Importantly, these findings provide additional support that the chloroviruses do not use the canonical host endoplasmic reticulum–Golgi glycosylation pathway to glycosylate their glycoproteins; instead, they perform glycosylation independent of cellular organelles using virus-encoded enzymes.  相似文献   
273.
AIM: To present a case series of MRCP-guided endoscopic biliary stent placement, performed entirely without contrast injection. METHODS: Contrast-free endoscopic biliary drainage was attempted in 20 patients with malignant obstruction, unsuitable for resection on the basis of tumor extent or medical illness. MRCP images were used to confirm the diagnosis of tumor, to exclude other biliary diseases and to demonstrate the stenoses as well as dilation of proximal liver segments. The procedure was carried out under conscious sedation. Patients were placed in the left lateral decubitus position. The endoscope was inserted, the papilla identified and cannulated by a papiUotome. A guide wire was inserted and guided deeply into the biliary tree, above the stenosis, by fluoroscopy. A papillotomy approximately 1 cm. long was performed and the papillotome was exchanged with a guiding-catheter. A 10 Fr' Amsterdam-type plastic stent, 7 to 15 cm long, was finally inserted over the guide wire/ guiding catheter by a pusher tube system.
RESULTS: Successful stent insertion was achieved in all patients. There were no major complications. Successful drainage, with substantial reduction in bilirubin levels, was achieved in all patients.
CONCLUSION: This new method of contrast-free endoscopic stenting in malignant biliary obstruction is a safe and effective method of palliation. However' a larger, randomized study comparing this new approach with the standard procedure is needed to confirm the findings of the present study.  相似文献   
274.
Adenosine deaminase (ADA) gene defects are among the most common causes of SCID. Restoration of purine metabolism and immune functions can be achieved by enzyme replacement therapy, or more effectively by bone marrow transplant or HSC gene therapy (HSC-GT). However, autoimmune complications and autoantibody production, including anti-nuclear antibodies (ANAs), frequently occur in ADA-SCID patients after treatment. To assess whether ADA deficiency affects the establishment of B cell tolerance, we tested the reactivity of recombinant antibodies isolated from single B cells of ADA-SCID patients before and after HSC-GT. We found that before HSC-GT, new emigrant/transitional and mature naive B cells from ADA-SCID patients contained more autoreactive and ANA-expressing clones, indicative of defective central and peripheral B cell tolerance checkpoints. We further observed impaired B cell receptor (BCR) and TLR functions in B cells after ADA inhibition, which may underlie the defects in B cell tolerance. Strikingly, after HSC-GT, ADA-SCID patients displayed quasi-normal early B cell tolerance checkpoints, as evidenced by restored removal of developing autoreactive and ANA-expressing B cells. Hence, ADA plays an essential role in controlling autoreactive B cell counterselection by regulating BCR and TLR functions.  相似文献   
275.
Phytohemagglutin-stimulated child and adult leukocytes equally supported CCR5-dependent (R5) and CXCR4-dependent (X4) HIV-1 replication. In contrast, when phytohemagglutin-stimulated leukocytes from either healthy or congenitally immunodeficient children were cultured on feeder cells, they well supported R5, but not X4 HIV-1 replication, whereas both viruses equally spread in adult cells maintained in similar conditions. Both child and adult cells showed similar levels of proliferation and surface expression of CD4, CCR5, CXCR4, CD25, CD69, and HLA-DR. Lack of X4 HIV-1 replication in child versus adult cells was not caused by a differential expression of several known HIV-1 restriction factors. Similar levels of HIV DNA synthesis occurred in child cells infected with R5 and X4 viruses up to 48 hours after infection when R5 HIV-1 showed a significantly superior capacity to spread in culture than X4 virus. Cultured child cells well supported single round vescicular stomatitis virus-G pseudotyped virus replication, whereas superinfection of R5-infected cells with X4 HIV-1 (or vice versa) rescued the replication of this latter virus. Thus, child cells exposed to feeder cell culture represent a novel model system in which the superior capacity of R5 versus X4 viruses to spread can be investigated in primary, untransformed CD4(+) cells.  相似文献   
276.
The genetic modification of T cells with a suicide gene grants a mechanism of control of adverse reactions, allowing safe infusion after partially incompatible hematopoietic stem cell transplantation (HSCT). In the TK007 clinical trial, 22 adults with hematologic malignancies experienced a rapid and sustained immune recovery after T cell-depleted HSCT and serial infusions of purified donor T cells expressing the HSV thymidine kinase suicide gene (TK(+) cells). After a first wave of circulating TK(+) cells, the majority of T cells supporting long-term immune reconstitution did not carry the suicide gene and displayed high numbers of naive lymphocytes, suggesting the thymus-dependent development of T cells, occurring only upon TK(+)-cell engraftment. Accordingly, after the infusions, we documented an increase in circulating TCR excision circles and CD31(+) recent thymic emigrants and a substantial expansion of the active thymic tissue as shown by chest tomography scans. Interestingly, a peak in the serum level of IL-7 was observed after each infusion of TK(+) cells, anticipating the appearance of newly generated T cells. The results of the present study show that the infusion of genetically modified donor T cells after HSCT can drive the recovery of thymic activity in adults, leading to immune reconstitution.  相似文献   
277.
Chronic kidney disease (CKD) is a common disorder whose prevalence is increasing worldwide. In Italy the prevalence of CKD, especially the early stages, is still not exactly known. Our study examines the prevalence and trends in ten years (1200 subjects in 1998-1999 and 1200 subjects in 2008-2009) of the estimated glomerular filtration rate (eGFR) in a population of southern Italy. We analyzed, within the VIP project, the prevalence of CKD (eGFR <60) in our area and its relationship to diabetes and hypertension as well as the trend between the years 1998-1999 and 2008-2009. The estimate of the GFR was obtained with the Cockcroft-Gault formula corrected for body surface area. The prevalence of CKD, stratified by the population of Campania, was about 5.9% in males and 3.9% in females in the years 1998-1999; ten years later (2008-2009) it had increased to 6.2% in males and 4.5% in females. The differences between males and females and between the two decades are not statistically significant although the trend shows a clear increase in subjects affected by CKD among both sexes. Among the male population the prevalence of CKD in persons with hypertension or diabetes, in those with both diseases, and in those free from these diseases was 11.2%, 12%, 13.8% and 6.3% (p=0.018), respectively. The same groups among females showed a CKD prevalence of 8%, 9.2%, 9.7% and 4.4%, respectively (p=0.042). Our work provides a picture of the prevalence of CKD in an area of southern Italy. It highlights the increase in CKD and calls upon a greater use of renal function tests in clinical practice, so that individuals at increased risk of developing cardiovascular complications may be detected as early as possible.  相似文献   
278.
A 40‐year‐old female, HIV positive, stage C, since 4 years, complained of a right cervical lymph node swelling. Two years before, the patient had been diagnosed with follicular B‐cell non‐Hodgkin lymphoma (FL); she had been treated with four cycles of multiagent chemotherapy plus rituximab, the last cycle being administered 10 months before coming to our attention. An ultrasound (US) guided fine‐needle cytology (FNC) showed an atypical lymphoid cell proliferation. The phenotype evidenced by flow cytometry (FC) analysis was D5: 10%, CD19: 49%, CD23: 10%, FMC7: 0%, CD10: 40%, CD10/19: 40%, lambda light chain 40%, kappa light chain 0%. FDG‐positron emission tomography (PET/CT) scan showed positivity in the corresponding cervical area. Since low LDH values and a reduced lymph node size were observed, the lymph node was therefore excised; the histology revealed a reactive hyperplastic lymph node with florid follicular pattern. A subsequent PCR analysis, performed on DNA extracted from a whole histological section, did not evidence IgH rearrangement. The patient is currently undergoing strict clinical and instrumental follow‐up, including PET every 3 months; after 13 months, she is alive without recurrence of lymphoma. Clonal B‐cell populations in non‐lymphomatous processes have been described in mucosa‐associated lymphoid cell populations and reactive lymph nodes, and are considered non‐malignant, antigen driven, proliferations of B‐lymphocytes determined by an abnormal response to bacterial or viral antigen stimulation. The present case occurred in an HIV patient and was clinically complex because of the patient's history of FL. This experience suggests much attention in the evaluation of radiological, cytological, and FC data and in clinical correlation in patients suffering from autoimmune or immunodeficiency syndromes. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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