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1.
Chinenye F Umego Clement I Mboto Atim D Asitok Linda C Osaji Uwem E George Uwem O Edet Elizabeth N Mbim Temitope OC Faleye Olubusuyi M Adewumi Johnson A Adeniji 《African health sciences》2022,22(1):511
IntroductionHepatitis B virus (HBV) infection continues to be a significant public health challenge globally, with higher disease burden in developing countries. HBV genotypes are associated with different geographical regions and clinical outcomes. Limited information exists on epidemiology of HBV in the Niger-Delta region (South-South) of Nigeria. Consequently, this study was designed to characterise hepatitis B virus infection among outpatients in selected tertiary hospitals in the region.MethodologyBetween June and August 2017, consenting nine hundred asymptomatic out-patients were enrolled and initially screened for HBV infection using one step Hepatitis B surface antigen (HBsAg) strip and subsequently re-tested using HBsAg and Hepatitis B core total antibody (anti-HBc) specific Enzyme-Linked Immunosorbent Assay (ELISA). Blood serum with detectable HBsAg were subsequently subjected to DNA extraction, S-gene amplification using a nested polymerase chain reaction (PCR) protocol, gel electrophoresis, sequencing and phylogenetic analysis.ResultsSeroprevalence of HBsAg was 4.6% (95% CI 2.5–7.1) and anti-HBc was 10.1% (95% confidence interval (CI) 6.1–15.3). Of the 41 HBsAg positive samples subjected to DNA extraction and HBV S-gene specific PCR, only 6 (14.6%) yielded the expected ∼408bp band. Phylogenetic analysis based on HBV pre-S/S sequences identified all six typable samples as genotype E, subtype ayw4 of the West African clade.ConclusionResults of the study confirm the presence and circulation of HBV genotype-E in the Niger-Delta region of Nigeria, thus corroborating the inclusion of the country in the Genotype E crescent. The authors advocate value-added HBV intervention in the region and the country at large. 相似文献
2.
Normal synthesis and expression of endothelial IIb/IIIa in Glanzmann's thrombasthenia 总被引:2,自引:0,他引:2
Glanzmann's thrombasthenia is a bleeding disorder, inherited in an autosomal recessive way and characterized by an absence or deficiency of the platelet glycoprotein (GP) IIb/IIIa complex. Recently, we and others demonstrated that cultured human umbilical vein endothelial cells synthesized a membrane protein complex similar to the platelet GP IIb/IIIa complex. In this article, we demonstrate that endothelial cells isolated from the umbilical vein of a newborn with Glanzmann's thrombasthenia, as compared with normal endothelial cells, show no difference in their ability to synthesize and express this GP IIb/IIIa complex. Our results indicate that Glanzmann's thrombasthenia is not accompanied by an "endotheliopathy." 相似文献
3.
Site‐Dependent Reference Point Microindentation Complements Clinical Measures for Improved Fracture Risk Assessment at the Human Femoral Neck 下载免费PDF全文
Stefania D'Angelo Douglas G Dunlop Richard OC Oreffo Cyrus Cooper and the Observational Study Examining Osteoporosis group 《Journal of bone and mineral research》2016,31(1):196-203
In contrast to traditional approaches to fracture risk assessment using clinical risk factors and bone mineral density (BMD), a new technique, reference point microindentation (RPI), permits direct assessment of bone quality; in vivo tibial RPI measurements appear to discriminate patients with a fragility fracture from controls. However, it is unclear how this relates to the site of the most clinically devastating fracture, the femoral neck, and whether RPI provides information complementary to that from existing assessments. Femoral neck samples were collected at surgery after low‐trauma hip fracture (n = 46; 17 male; aged 83 [interquartile range 77–87] years) and compared, using RPI (Biodent Hfc), with 16 cadaveric control samples, free from bone disease (7 male; aged 65 [IQR 61–74] years). A subset of fracture patients returned for dual‐energy X‐ray absorptiometry (DXA) assessment (Hologic Discovery) and, for the controls, a micro‐computed tomography setup (HMX, Nikon) was used to replicate DXA scans. The indentation depth was greater in femoral neck samples from osteoporotic fracture patients than controls (p < 0.001), which persisted with adjustment for age, sex, body mass index (BMI), and height (p < 0.001) but was site‐dependent, being less pronounced in the inferomedial region. RPI demonstrated good discrimination between fracture and controls using receiver‐operating characteristic (ROC) analyses (area under the curve [AUC] = 0.79 to 0.89), and a model combining RPI to clinical risk factors or BMD performed better than the individual components (AUC = 0.88 to 0.99). In conclusion, RPI at the femoral neck discriminated fracture cases from controls independent of BMD and traditional risk factors but dependent on location. The clinical RPI device may, therefore, supplement risk assessment and requires testing in prospective cohorts and comparison between the clinically accessible tibia and the femoral neck. © 2015 American Society for Bone and Mineral Research. 相似文献
4.
Expression and purification of functional recombinant epitopes for the platelet antigens, PlA1 and PlA2 总被引:1,自引:1,他引:1
The platelet antigens, PlA1 and PlA2, are responsible for most cases of posttransfusion purpura (PTP) and neonatal alloimmune thrombocytopenia (NAIT) in the caucasian population and are determined by two allelic forms of the platelet glycoprotein GPIIIa gene. To study the interaction between these antigens and their respective antibodies, we inserted the sequence that encodes the signal peptide and the N- terminal 66 amino acids of the PlA1 form of GPIIIa into the expression vector pGEX1. To express the PlA2 antigen, nucleotide 196 of the PlA1 coding sequence was mutated to the PlA2 allelic form. When transformed and induced in Escherichia coli, the two constructs produce glutathione S-transferase (GST)/N-terminal GPIIIa fusion proteins, one containing leucine at position 33 (PlA1), the other proline (PlA2). These proteins are easily purified in milligram quantities using glutathione-Sepharose and react specifically with their respective antibodies by immunoblot and enzyme-linked immunosorbent assay. Antigenicity of the PlA1 fusion protein in reduced glutathione increases with time; moreover, the addition of oxidized glutathione accelerates this process, presumably because of formation of the native disulfide bonds. Neutralization assays indicate that the PlA1 fusion protein competes for all of the anti-PlA1 antibody in the serum of patients with PTP and NAIT that is capable of interacting with the surface of intact platelets. This study shows that the GST/N-terminal GPIIIa fusion proteins contain conformational epitopes that mimic those involved in alloimmunization, and that regions other than the amino terminal 66 amino acids of GPIIIa are not likely to contain or be required for the development of functional PlA1 epitopes. Furthermore, these recombinant proteins can be used for the affinity-purification of clinical anti-PlA1 antibodies and specific antibody identification by western blotting, making them useful in the diagnosis of patients alloimmunized to PlA1 alloantigens. 相似文献
5.
Leeksma OC; Meijer-Huizinga F; Stoepman-van Dalen EA; van Ginkel CJ; van Aken WG; van Mourik JA 《Blood》1986,67(5):1460-1467
Concentrations of plasma fibrinopeptide A (FPA) were measured by radioimmunoassay in 50 patients with venous thromboembolism or disseminated intravascular coagulation or both. A consistent discrepancy was observed in values obtained with two anti-FPA antisera. Analysis of extracts from plasma of these patients by high-performance liquid chromatography (HPLC) revealed the presence of a phosphorylated and an unphosphorylated form of the A peptide. Differences in concentrations of FPA measured with the two antisera could be accounted for by their different reactivity with phosphorylated FPA (FPA-P). The differences were abolished by treatment with alkaline phosphatase. A good correlation was observed between the FPA-P content of free A- peptide material and of fibrinogen in plasma as determined by HPLC (r = .88, P less than .001, n = 11). In patients with elevated FPA levels, the mean FPA-P content of fibrinogen was significantly higher (P less than .002, n = 13) than in patients with normal FPA levels (n = 8) and in healthy controls (n = 14). Phosphorus in fibrinogen did not correlate with fibrinogen degradation products or fibrinogen levels and became normal on adequate anticoagulation. Therefore, blood-clotting activation may lead to a high phosphate content of fibrinogen and of free FPA in plasma. 相似文献
6.
Lica Chui MD Tara Fraser OC COMT Karen Hoar MD G. Robert LaRoche MD FRCSC 《Journal of AAPOS》2004,8(6):566-570
PURPOSE: Nova Scotia has a vision screening program which assesses children aged 4[1\2] to 5[1\2] years. However, its use in younger children proved impossible. This study will examine a modified screening protocol for the younger children (3 to 4 years old) and determine its negative predictive value and minimum age for reliable application. MATERIALS AND METHODS: Public health nurses administered the study protocol to 3- to 4-year-old children. One hundred seventy-eight children were screened over two summers. Medical and family history, external inspection, as well as measures of visual acuity with the Lea Hyvarinen symbols chart and stereoacuity with Frisby plates were recorded. Results were compared with a gold standard examination that included full orthoptic and ophthalmologic evaluations. One hundred forty-one (79%) children underwent the gold standard examination. Agreement between screening and gold standard examinations was studied. RESULTS: Data showed increased concordance between screening and gold standard examination results with increasing age up to 41 months. Negative predictive value (NPV) and specificity also improved when data were separated by this age. In children <41 months old, the screening test NPV was 90%, specificity, 68%, and sensitivity, 75%. In comparison, children >/=41 months old had screening test NPV of 96%, specificity, 95%, and sensitivity, 50%. Specificity was higher in the older age group ( P < 0.001). Sensitivity was lower ( P = 0.004). CONCLUSION: This study's vision screening protocol appears better suited for children 41 months and older. They had better pass/fail reproducibility than children <41 months. The test's simplicity allows easy use by non-eye-care professionals. It could potentially lower the reliable screening age of children by 13 months, from 54 months of age (4[1\2] years old) to 41 months. This screening may miss some refractive errors and microtropia/monofixation syndrome, despite normal visual acuity, stereoacuity, and external inspection. 相似文献
7.
Matthew Stern MD Werner Poewe MD C. Warren Olanow MD FRCPC Wolfgang Oertel MD José Obeso MD PhD Kenneth Marek MD Irene Litvan MD Anthony E. Lang OC MD FRCPC Glenda Halliday PhD Christopher G. Goetz MD Thomas Gasser MD Bruno Dubois MD PhD Piu Chan MD PhD Bastiaan R. Bloem MD PhD Charles H. Adler MD PhD Günther Deuschl MD 《Movement disorders》2015,30(12):1591-1601
This document presents the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's disease (PD). The Movement Disorder Society PD Criteria are intended for use in clinical research but also may be used to guide clinical diagnosis. The benchmark for these criteria is expert clinical diagnosis; the criteria aim to systematize the diagnostic process, to make it reproducible across centers and applicable by clinicians with less expertise in PD diagnosis. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations; these are incorporated into both the current criteria and particularly into separate criteria for prodromal PD. Similar to previous criteria, the Movement Disorder Society PD Criteria retain motor parkinsonism as the core feature of the disease, defined as bradykinesia plus rest tremor or rigidity. Explicit instructions for defining these cardinal features are included. After documentation of parkinsonism, determination of PD as the cause of parkinsonism relies on three categories of diagnostic features: absolute exclusion criteria (which rule out PD), red flags (which must be counterbalanced by additional supportive criteria to allow diagnosis of PD), and supportive criteria (positive features that increase confidence of the PD diagnosis). Two levels of certainty are delineated: clinically established PD (maximizing specificity at the expense of reduced sensitivity) and probable PD (which balances sensitivity and specificity). The Movement Disorder Society criteria retain elements proven valuable in previous criteria and omit aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of PD expands, the Movement Disorder Society criteria will need continuous revision to accommodate these advances. © 2015 International Parkinson and Movement Disorder Society 相似文献
8.
9.
Red blood cell substitutes 总被引:2,自引:0,他引:2
Thomas Ming Swi Chang OC MD CM PhD FRCP Director 《Best Practice & Research: Clinical Haematology》2000,13(4):651-667
Soluble polymerized haemoglobin (polyhaemoglobin) is now in a phase III clinical trials. Patients have received up to 20 units (10 litres) in trauma surgery and other surgery. Polyhaemoglobin can be stored for more than 1 year. Haemoglobin solutions have no blood group antigen and can be used as a 'universal donor' oxygen carrier. They can also be sterilized. With a circulation half-life of 24 hours they are undergoing trials for peri-operative use. For conditions with potential for ischaemia-reperfusion injuries, a new polyhaemoglobin-superoxide dismutase-catalase, which can reduce oxygen radicals, is being developed. Recombinant human haemoglobin has been tested in clinical trials, and a new type of recombinant human haemoglobin that has low affinity for nitric oxide is being developed for clinical trials. To increase the circulation time, artificial red blood cells have been prepared with a bilayer lipid membrane (haemoglobin liposomes) or with a biodegradable polymer membrane-like polylactide (haemoglobin nanocapsules). Synthetic chemicals such as perfluorochemicals are also being developed and tested in clinical trials as red blood cell substitutes. 相似文献
10.