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排序方式: 共有284条查询结果,搜索用时 16 毫秒
241.
Gowtham Kankanala MS MCh Amar Singh Jain FRCS ED 《The Journal of foot and ankle surgery》2007,46(4):213-217
A retrospective study was carried out on 48 patients to correlate preoperative ultrasound findings with postoperative histopathology findings and to assess the sensitivity, specificity, positive predictive values, and negative predictive values of ultrasound in the diagnosis of Morton's interdigital neuroma. All case sheets of 48 patients operated on between 1997 and 2005 were reviewed in the medical record section of Ninewells Hospital, Dundee, Scotland, so that preoperative ultrasound reports were compared with the postoperative histopathological reports. A statistical analysis of the results was performed. Ultrasonography showed 43 true-positive cases, 1 true-negative case, and 4 false-negative cases out of 48 cases. Histopathology showed 47 true-positive cases and 1 true-negative case; statistical analysis performed on the results showed a sensitivity of 91.48%, a specificity of 100%, and 100% positive and 20% negative predictive values, respectively. In our analysis, the probability that ultrasound will confirm the presence of plantar intermetatarsal neuroma is 91.67%. 相似文献
242.
Use of monoclonal antihapten antibodies for immunolocalisation of tissue antigens 总被引:4,自引:2,他引:2
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The applicability of a hapten-antihapten sandwich technique incorporating a monoclonal antihapten bridge antibody to localisation of tissue antigen is described. The results show that the method is both versatile and selective and has the potential of being even more sensitive than currently used immunoperoxidase methods. 相似文献
243.
244.
Neural dynamics in a model of the thalamocortical system. II. The role of neural synchrony tested through perturbations of spike timing 总被引:1,自引:1,他引:0
Activity in the mammalian thalamocortical system is often accompanied by a
synchronous discharge of cortical and thalamic neurons. Although many
functions have been attributed to such synchronous firing, it is not known
whether or how synchrony of firing per se affects thalamocortical
operations. Direct experimental tests of the consequences of neuronal
synchronization in vivo are hard to carry out, whereas theoretical studies
based on single-neuron models cannot reveal the effects of synchrony at the
system level. To overcome these limitations, we have used a perturbational
approach to test the causal efficacy of synchrony per se in large-scale
simulations of the thalamocortical system. The test consists of selectively
disrupting firing synchrony by 'jittering' the timing of action potentials
in the simulations and determining whether firing rates are modified by
this perturbation. The simulations are based in detail on the known anatomy
and physiology of the thalamocortical-visual system of the cat, and have
been shown in a companion paper to produce episodes of fast synchronous
activity at multiple levels. By carrying out the perturbation analysis, we
established that neurons can have long membrane time constants (8-16 ms)
and balanced synaptic activations, and yet function collectively in such a
way that synchrony within a time window of 4 ms significantly affects the
rates and selectivity of the responses to visual stimuli. The simulations
also revealed a complex interplay, at the network level, between synchrony
of firing and rate of firing. The dynamic consequences of firing synchrony
were most evident when spike jittering was applied to specific polysynaptic
loops involving corticocortical and corticothalamic connections. These
results support the view that firing synchrony within thalamocortical and
corticocortical loops plays a causal role in the cooperative and
competitive neural interactions that produce pattern-selective responses in
the cortex.
相似文献
245.
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247.
Of the first 350 bases upstream of the ATG signal sequences were obtained representing the following HLA-A locus alleles: A*01, A*0102, A*02, A*0202, A*0206, A*0207, A*03, A*0302, A11.2, A11.1, A*68, A*68011, A*30, A*3002, A*23, A*24, A*26, A*2602, A*25, A*29, A*2902, A*31, A*31011, A*32, A*3201, A*33, A*3301, A*3303, A*34, A*6601, A*6602 A*74, A*80. We found 21 polymorphic positions of which a surprisingly large number (altogether 9) represent allele specific exchanges. For all 35 alleles tested of the HLA-A locus we found 16 different types of promoter. While all tested A2 subtypes, A*0201, A*0202, A*0206, A*0207 share the same promoter, there were in contrast several situations in which different subtypes of the same group have different promoters. This is true for HLA A*01, A*0102; A*03, A*0302; A*30, A*3002; A*6601, A*6602; A*32, A*3201; A*29, A*2902. Looking at the binding sites for nuclear factors, we observe that TATA-box, CAT-box, Enhancer B, the interferon response sequence and the Enhancer A (except HLA-A30 has one base exchange) are conserved within the HLA-A locus. The interferon response sequence shows for all A-locus alleles a double base pair exchange (TT for AC). In comparison with the promoter polymorphism of the HLA-B locus (Yao et al., 1995) we find a surprising diversity of the promoters in the HLA-A locus. While for the B-locus promoters large groups of sometimes strongly different alleles share the same promoter, in the HLA-A locus there is a private promoter for almost each allele and sometimes even each subtype. This lead to the conclusion that the promoter polymorphisms of the HLA-A and the HLA-B locus have been subjected to different selection pressure in evolution. 相似文献
248.
The mini-micro-epididymal sperm aspiration for sperm retrieval: a study of urological outcomes 总被引:1,自引:5,他引:1
Nudell DM; Conaghan J; Pedersen RA; Givens CR; Schriock ED; Turek PJ 《Human reproduction (Oxford, England)》1998,13(5):1260-1265
Epididymal sperm aspiration and in-vitro fertilization (IVF) with
intracytoplasmic sperm injection is an established treatment for
obstructive azoospermia. Sperm aspiration is performed with either an
incision or percutaneously. To control costs, minimize morbidity and retain
the advantages of both approaches, we developed a mini-incision technique
for epididymal aspiration and here report sperm retrieval and
procedure-related outcomes. Twenty-six consecutive patients with
obstructive azoospermia underwent epididymal sperm retrieval through a 1 cm
incision with local anaesthesia to provide spermatozoa for concurrent IVF
cycles. The quality of retrieved spermatozoa, the quantity of spermatozoa
cryopreserved as well as anaesthetic requirement, recovery time and patient
satisfaction were evaluated. Fresh epididymal spermatozoa were retrieved in
25 of 26 (96%) patients. In one patient, testicular sperm extraction was
necessary. Excess motile spermatozoa were cryopreserved in 24 of 26 (92%)
patients; a mean total motile count of 4.8x10(6) motile spermatozoa were
banked. The procedure was performed with 62% of patients receiving minimal
i.v. sedation. Post-procedure recovery was rapid, with a median time to
return to work of 2.0 days with a median of 2.0 pain pills taken.
Procedure-related satisfaction was high. The mini-micro-epididymal sperm
aspiration achieves the goals of reliable retrieval of abundant epididymal
spermatozoa with a single, minimally morbid procedure. It appears to
combine the advantages of the incision and percutaneous approaches.
相似文献
249.
Accuracy of specific IgE in the prediction of asthma: development of a scoring formula for general practice 总被引:2,自引:0,他引:2
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Petra ED Eysink Gerben ter Riet Rob C Aalberse Wim MC van Aalderen Carel M Roos Jaring S van der Zee Patrick JE Bindels 《The British journal of general practice》2005,55(511):125-131
BACKGROUND: For the diagnosis of asthma in young children, GPs have to rely on history taking and physical examination, as spirometry is not possible. The additional diagnostic value of specific immunoglobulin E (IgE) to inhalent allergens remains unclear. AIM: To assess the predictive accuracy of specific IgE to cat, dog, and/or house dust mites in young children for the subsequent development of asthma at the age of 6 years. DESIGN OF STUDY: Prospective follow-up study. SETTING: Seventy-two general practices. METHOD: A total of 654 children, aged 1-4 years, visiting their GPs for persistent coughing (>/= 5 days), were tested for IgE antibodies by radio allergosorbent testing (RAST). Parents completed a questionnaire on potential risk indicators. Those children who showed an IgE-positive status (12.7%) and a random sample of those with an IgE-negative status (<0.5 U/ml) were followed up to the age of 6 years when the asthma status was established. The main outcome measure was asthma at the age of 6 years (combination of both symptoms and/or use of asthma medication, and impaired lung function). RESULTS: Addition of RAST results to a prediction model based on age, wheeze, and family history of pollen allergy increased the area under the receiver operating characteristic (ROC) curve from 0.76 to 0.87. Furthermore, RAST improved patient differentiation as indicated by a change in the range of asthma probabilities from 6-75% before the IgE test, to 1-95% after the IgE-test. CONCLUSION: Sensitisation to inhalant allergens in 1-4-year-olds, as shown by RAST, is a useful diagnostic indicator for the presence of asthma at the age of 6 years, even after a clinical history has been obtained. This model should preferably be validated in a new population before it can be applied in practice. 相似文献
250.
PURPOSE: The cellular and molecular mechanisms that regulate the organization of bladder urothelium into basal, intermediate and superficial cell layers remain poorly understood. We tested the hypothesis that fibroblast growth factor (FGF)-7 is essential for generating a multilayered stratified bladder epithelium. MATERIALS AND METHODS: The morphological and molecular characteristics of bladder urothelium in age and sex matched FGF-7 +/+ wild-type and -/- null mice were evaluated. In addition, the effect of exogenous FGF-7 on the growth and differentiation of primary murine urothelial cells was assessed. RESULTS: Morphometric analyses demonstrate that FGF-7 null urothelium is markedly thinned compared with wild-type urothelium. Electron microscopy revealed that null urothelium lacks the intermediate cell layers and molecular marker analyses confirmed this observation. In vitro cell culture experiments indicated that FGF-7 regulates urothelial cell growth, differentiation and stratification. Primary urothelial cultures maintained without FGF-7 ceased to divide and expressed proteins characteristic of terminally differentiated umbrella cells. In contrast, cultures maintained with exogenous FGF-7 contained proliferating epithelial cells with protein expression patterns consistent with those of intermediate cells in addition to terminally differentiated, post-mitotic umbrella cells. Importantly, isolated urothelial cells maintained with exogenous FGF-7 formed a multilayered epithelium in vitro. CONCLUSIONS: Collectively these data indicate that FGF-7 is essential for normal bladder urothelial stratification, specifically the formation of the intermediate cell layers. Fibroblast growth factor-7 stimulates urothelial proliferation and delays the differentiation of these cells into post-mitotic umbrella cells. 相似文献