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1.
Long-term follow-up of 27 patients with hepatitis B virus-related chronic liver disease treated by transplantation showed that 23 had hepatitis B virus recurrence. In 13 patients late changes in the grafts were similar to those described in other series: minor abnormalities in five cases, chronic active hepatitis in five cases and non-hepatitis B virus-related graft dysfunction in three cases. Three patients had incomplete histological follow-up. Analysis of the histological changes and viral antigen expression in six cases revealed a distinct and novel pattern termed fibrosing cholestatic hepatitis. Development of fibrosing cholestatic hepatitis was associated with rapidly progressive graft dysfunction. It is postulated that this pattern of fibrosing cholestatic hepatitis develops because of a high cytoplasmic expression of viral antigens, including HBsAg. The remaining case had some features of fibrosing cholestatic hepatitis. The main histological features of this unique syndrome include thin, perisinusoidal bands of fibrosis extending from portal tracts to surround plates of ductular-type epithelium; prominent cholestasis; ground-glass transformation; and ballooning of hepatocytes with cell loss and mild mixed inflammatory reaction.  相似文献   
2.
Rabbit trace eyeblink conditioning is a hippocampus-dependent task in which the auditory conditioned stimulus (CS) is separated from the corneal airpuff unconditioned stimulus (US) by a 500-ms empty trace interval. Young rabbits are able to associate the CS and US and acquire trace eyeblink conditioned responses (CRs); however, a subset of aged rabbits show poor learning on this task. Several studies have shown that CA1-hippocampal activity is altered by aging; however, it is unknown how aging affects the interaction of CA1 single neurons within local ensembles during learning. The present study examined the extracellular activity of CA1 pyramidal neurons within local ensembles in aged (29-34 mo) and young (3-6 mo) rabbits during 10 daily sessions (80 trials/session) of trace eyeblink conditioning. A single surgically implanted nonmovable stereotrode was used to record ensembles ranging in size from 2 to 12 separated single neurons. A total of six young and four aged rabbits acquired significant levels of CRs, whereas five aged rabbits showed very few CRs similar to a group of five young pseudoconditioned rabbits. Pyramidal cells (2,159 total) were recorded from these four groups during training. Increases in CA1 pyramidal cell firing to the CS and US were diminished in the aged nonlearners. Local ensembles from all groups contained heterogeneous types of pyramidal cell responses. Some cells showed increases while others showed decreases in firing during the trace eyeblink trial. Hierarchical clustering was used to isolate seven different classes of single-neuron responses that showed unique firing patterns during the trace conditioning trial. The proportion of cells in each group was similar for six of seven response classes. Unlike the excitatory modeling patterns reported in previous studies, three of seven response types (67% of recorded cells) exhibited some type of inhibitory decrease to the CS, US, or both. The single-neuron response classes showed different patterns of learning-related activity across training. Several of the single-neuron types from the aged nonlearners showed unique alterations in response magnitude to the CS and US. Cross-correlation analyses suggest that specific single-neuron types provide more correlated single-neuron activity to the ensemble processing of information. However, aged nonlearners showed a significantly lower level of coincident pyramidal cell firing for all cell types within local ensembles in CA1.  相似文献   
3.
Gowns and coveralls are important components of protective ensembles used during the management of known or suspected Ebola patients. In this study, an Elbow Lean Test was used to obtain a visual semi-quantitative measure of the resistance of medical protective garments to the penetration of two bodily fluid simulants. Tests were done on swatches of continuous and discontinuous regions of fabrics cut from five gowns and four coveralls at multiple elbow pressure levels (2–44 PSI). Swatches cut from the continuous regions of one gown and two coveralls did not have any strike-through. For discontinuous regions, only the same gown consistently resisted fluid strike-through. As hypothesized, with the exception of one garment, fluid strike-through increased with higher applied elbow pressure, was higher for lower fluid surface tension, and was higher for the discontinuous regions of the protective garments.  相似文献   
4.
Phosphatidylinositol 3-kinase (PI3-kinase) and phosphatidylinositol 4-kinase (PI4-kinase) enzymes are an important family of signaling molecules that have been implicated in the regulation of intracellular vesicle trafficking. It has previously been shown that PI3-kinase and PI4-kinase enzymes regulate neuronal survival and the retrograde axonal transport of nerve growth factor in sympathetic and sensory neurons. We have extended these studies to examine the role these enzymes play in the regulation of the retrograde axonal transport of neurotrophin-3 (NT-3) and neurotrophin-4 (NT-4) in sympathetic and sensory neurons in vivo. Wortmannin (0.1 nmol/eye), a PI3-kinase and PI4-kinase antagonist, reduced the amount of (125)I-NT-3 retrograde transport in sympathetic neurons by approximately 50% and (125)I-NT-4 in sympathetic neurons by approximately 40% and sensory neurons by approximately 20%. The PI3-kinase antagonist LY294002 (100 nmol/eye) reduced the retrograde axonal transport of (125)I-NT-4 in sympathetic and sensory neurons, and (125)I-NT-3 in sympathetic neurons. Phenylarsine oxide (PAO), a PI4-kinase antagonist, significantly inhibited (125)I-NT-4 retrograde axonal transport in sympathetic and sensory neurons. These results show that wortmannin-sensitive PI3-kinases and PI4-kinases may be involved in NT-3 and NT-4 retrograde axonal transport. The retrograde axonal transport of neurotrophic factors in sympathetic and sensory neurons in vivo appears to depend upon the activation of different receptors and second messenger cascades at the nerve terminal.  相似文献   
5.
OBJECTIVE. We identified the potential clinical and sonographic predictors of the spontaneous resolution of ectopic pregnancies. SUBJECTS AND METHODS. We performed a prospective study of 78 consecutive patients with a transvaginal sonographic diagnosis of ectopic pregnancy who had either two consecutive quantitative measurements of their beta subunit of human chorionic gonadotropin (beta-hCG) more than 24 hrs apart or an embryo with a heart beat. We evaluated the patient's age, time from the last menstrual period, beta-hCG level, size of ectopic pregnancy, presence of a gestational sac or embryonic elements, vascularity on color Doppler sonography, peak systolic velocity, and resistive index of ectopic pregnancy at the time of presentation as potential independent predictors of the final outcome. Logistic regression was performed to identify the independent predictors. RESULTS. Forty-six patients had declining beta-hCG levels, and 32 ectopic pregnancies showed an embryo with a heart beat or had steady or rising beta-hCG levels. Univariate analysis indicated that a longer time from the last menstrual period (older ectopic pregnancies), lower beta-hCG levels, and the absence of gestational sac are statistically more significantly seen in ectopic pregnancies with declining beta-hCG levels (p < 0.05). Resistive index of ectopic pregnancy reached borderline significance (p = 0.05). In a multiple logistic model, the same variables were independent predictors of outcome (p < 0.05). Resistive index was also a predictor (p = 0.09). CONCLUSION. Longer times from the last menstrual period, lower beta-hCG levels, absence of gestational sacs, and higher resistive indexes of ectopic pregnancy at the time of presentation appear to be independent predictors of the spontaneous resolution of ectopic pregnancy.  相似文献   
6.
Family clustering of avian influenza A (H5N1)   总被引:7,自引:0,他引:7  
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7.
The objective of this research is to analyse the causal relationship between construction of fixed bridge dentures and the intensity of halitosis manifestations, as well as to establish basic hygiene requirements for construction of fixed dentures which would completely exclude retention of food particles and avoid bad breath. 48 patients (36 men and 12 women), who use fixed dentures for 2-10 years, have been involved in this research. 26 patients wore fixed bridge dentures made of punched tooth crowns, the other 22 patients wore cast fixed dentures. The obtained measurements of halitosis magnitude point to the close connection between bad breath and the construction of fixed dentures. Fixed dentures with tooth crown laps, saddle intermediate parts, as well as denture constructions, which impede complex of mouth hygiene measures, cause bad breath. In this research, the condition of patients' teeth, periodontium, and oral cavity hygiene have been evaluated as satisfactory; the tongue is not perceptibly coated, and patients etiologically have not experienced problems caused by respiratorial or gastrointestinal diseases. The examined patients have not complained of xerostomia problems. In conclusion, it should be admitted that fixed dentures, which make difficult or even completely impede the complex of oral cavity hygiene measures, intensify the development of halitosis.  相似文献   
8.
Twenty-two patients had combined radiographic and radiocolloid arthrography. The two procedures were in agreement in 86% of the patients as to whether the femoral component was loose or not. Fourteen patients has surgical revision of the prosthesis and in 3 (23%) radiographic arthrography was falsely negative. No false negative results were obtained with radiocolloid arthrography thus far. The radionuclide method cannot be used to assess the acetabular component.  相似文献   
9.
Telemedicine in China   总被引:2,自引:0,他引:2  
Telemedicine has been shown to have a considerable impact in medical education, conferencing and consultation. As a result, the People's Republic of China has been keen to develop telemedicine. In her attempts to further the development of telemedicine, China has looked to the progress of medical services in Western countries such as Europe and North America. The United States of America, however, has exceeded the rest in exchange of health-care information and telemedicine technologies with China. Although China has been enthusiastic about the exchange, telemedicine in China requires development in the technical infrastructure and professional infrastructure.  相似文献   
10.
In June 2000, twenty-eight infertile couples were treated by in vitro fertilization and embryo transfer at our initial assisted reproduction programme carried out in conjunction with Midland Fertility Services, Aldridge, Birmingham, England. A pre-requisite for treatment was that on day 3 of the menstrual cycle the levels of follicle stimulating hormone (FSH) and oestradiol (E2) should be < 10 i mu/l and < 100 pg/ml respectively in the female partner. The ages of the women ranged from 26 to 42 years with a mean age of 35.5 years. Down regulation was carried out by using buserelin acetate 0.5 microgram subcutaneously from day 21 of the cycle for 21 days. This process was completed when the ovaries and pituitary gland were quiescent and the endometrial thickness < 4 mm in diameter. On completion of down regulation the gonadotrophin hormone, pergonal (dosage of 150-450 units) was used for ovarian hyperstimulation. A total of 294 oocytes (mean of 10.5, range 2-45) were retrieved of which 138 were fertilized (mean of 4.9, range of 0-28). Twenty-four patients each received a mean of two embryos. Five patients (20.8%) had positive pregnancy tests. Three patients (0.1%) developed ovarian hyperstimulation syndrome (OHSS), one had the severe, and two, the mild form of the syndrome. All three cases were treated successfully. The success at the initial IVF controlled ovarian hyperstimulation augers well for the future of infertile couples seeking treatment at the Fertility Management Unit, The University of the West Indies, Jamaica.  相似文献   
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