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51.
52.
Granulocytic ehrlichiosis in two dogs in Switzerland.   总被引:11,自引:5,他引:6       下载免费PDF全文
This case report describes two dogs with granulocytic ehrlichiosis. Dog 1 was a male Labrador retriever with clinical signs of lymphosarcoma. Dog 2 was a female Airedale terrier, whose clinical signs included apathy, pyrexia, diarrhea, and abdominal pain. Examination of blood smears revealed Ehrlichia organisms in the neutrophils of both dogs. There was thrombocytopenia in both dogs, and dog 2 also had leukopenia. In both dogs, bands of identical length were amplified from DNA of leukocytes via nested PCR. The bands had identical nucleotide sequences, which differed from the gene sequences of Ehrlichia equi and E. phagocytophila in three and two positions, respectively. Interestingly, the nucleotide sequence of the 16S rRNA was 100% homologous to that of a human granulocytic ehrlichia.  相似文献   
53.
Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.  相似文献   
54.
46 patients suffering from various malignancies (17 non Hodgkin lymphomas, 12 Hodgkin's diseases, 11 acute leukaemias, 4 myelomas, 2 carcinomas), 6 patients with haematological disorders such as ITP, SAA, myeloproliferative disease, LAS and 3 patients without preexisting disease were treated with acyclovir for herpes virus infection diagnosed by clinical means. All but 7 patients had been given intensive treatment with various cytostatic agents and/or irradiation. Most patients were treated with 1500 mg acyclovir daily for 5 to 13 days. Dosage was adjusted according to renal function and clinical response in the remaining 10 cases. 11 patients received intravenous immunoglobulins in addition. Side effects were negligible (local irritation, minimal rise in serum creatinine levels in 5 patients). All patients responded to treatment; 6 patients complained of severe neuralgia lasting for more than one month; 5 patients relapsed.  相似文献   
55.
To characterize the site-specific mechanical and histological properties in fracture repair and to relate these properties to the initial mechanical situation, an experimental fracture model was used in the metatarsus of 42 sheep. the mechanical situation of a transverse osteotomy was described by three gap sizes (1,2, or 6 mm) and two amounts of strain (7 or 31 %). An external fixator that allowed a defined axial movement provided control of these settings. Nine weeks following surgery, the healing area was dissected and tensile and compressive properties were measured in subregions of the fracture gap and the periosteal callus. The central, sagittal section was used for quantitative histology. We found the quality of the tissue along the osteotomy line to be most important for regaining mechanical stability. Increasing the size of osteotomy gaps resulted in poorer mechanical and histological qualities, and the repair process was less complete. Interfragmentary strain did not significantly influence the repair process. The smaller strain levels had already stimulated the secondary repair process, and this stimulatory effect could not be further enhanced by increasing the amount of strain. Our finding that large gaps between bone segments were not as well healed as were smaller gaps suggests that it is advantageous to avoid large gaps in fracture treatment.  相似文献   
56.
Abstract: In 1982 the IGCI CLL cooperative group decided to investigate the usefulness of treating, at diagnosis B-cell chronic lymphocytic leukemia (CLL) in early and stable phase of the disease. From January 1982 to December 1986, 148 patients were randomized either to receive immediate treatment with chlorambucil (CLB) or to defer therapy to the time of progression. The early and stable phase of the disease was defined by a total tumor mass (TTM) score < 9, the absence of anemia or thrombocytopenia and a doubling time > 12 months. The main end-point of the study was survival. At the last evaluation in April 1993, after a median follow-up of 75 months, no significant difference was found in overall survival between early vs. deferred treatment patients from every cause of death as well as from death due to CLL-related causes only. The same results were obtained when the patients in more favorable stages, such as Binet stage A and TTM < 4.5, were considered. Interestingly, the incidence of epithelial cancer was similar in the two groups. Early treatment was associated with a significantly better response and a lower progression rate. From this long-term experience, it can be concluded that immediate chemotherapy with CLB is not beneficial for CLL patients in early and stable phase of the disease in terms of survival.  相似文献   
57.
The purpose of our study was to evaluate the protective effect of a new silicone-containing barrier-cream (Anthydro) and its vehicle (Anthydro without silicone) in the prevention of cutaneous irritation by detergents. We therefore planned a study in several stages, using an anionic surfactant well known for its irritant properties: sodium laurylsulphate (SLS) in aqueous solution. In a first series of experiments, the protective effect of the Anthydro cream against SLS was studied by invasive methods on guinea-pigs in order to determine histologically the protective effect of the cream when a 10 p. 100 SLS solution was applied on the skin under occlusion during 24 hours (Square chambers, Van der Bend). Typical and reproducible lesions were apparent, and the protected sites were compared with the unprotected sites. In parallel, we used non-invasive methods (conductivity, transepidermal water loss and cutaneous blood flow) to determine in humans the protective effect of Anthydro cream in comparison with unprotected sites after application during 24 hours of patches soaked with a 5 p. 100 SLS solution on the forearms of 13 adult and healthy volunteers (Silver patch tests, Van der Bend). In both experiments the Anthydro cream was effective in reducing the SLS-induced cutaneous irritation. In a second series of experiments, the Anthydro barrier-cream was compared with its "base" (Anthydro without silicone) in terms of effectiveness, following the same experimental procedure (invasive on guinea-pigs, and non-invasive on humans). The base was shown to be effective in protecting against irritation. However, the histological lesions were less intense when the skin was protected by Anthydro than by its vehicle. Concerning the non-invasive methods in humans, no significant statistical differences appeared in the measurement of various parameters between the sites protected by Anthydro and the sites protected by the vehicle. These results lead us to suggest the existence of an essentially mechanical protective effect in which the silicone plays a very small part in terms of effectiveness. These experimental results necessitates further investigations to be extrapolated to occupational conditions without tests performed in industries and well-conducted epidemiological investigations.  相似文献   
58.
An important feature of multi ring positron tomographs is the inter plane septa, the purpose of which is to reduce random and scattered coincidences. In general, such septa also eliminate the coincidence lines of response between pairs of detectors more than one ring apart. The operation of a camera without septa must result in an increase not only in the true coincidence rate, but also in the singles, and therefore in the dead time and randoms rate, and in the scattered coincidences. A configuration option in the coincidence hardware of the 8 ring, 15 slice ECAT 931/08-12 enables a full set of 64 sinograms to be acquired when the septa are removed. The detector normalisation and transmission data for studies with the septa out can be obtained using a rotating pin source. To take maximum advantage of the additional signal, the emission data must be reconstructed using a fully three dimensional reconstruction algorithm. This paper presents an analysis of some phantom studies acquired without septa and reconstructed in three dimensions. The results are compared with data acquired with septa for the same phantoms imaged under similar conditions. It is found that, with the septa removed, the signal to noise for a uniform, 20 cm diameter cylinder improves by a factor of 2.8 in the centre of the field of view, whereas in regions distant from the centre in the axial direction, the signal to noise decreases due to the increase in scatter and randoms. An improvement in signal to noise is observed in 6 cm of the 10 cm axial length of the tomograph.This article was presented at the 1st EEC workshop on accuracy determination in PET, January 19–20th. 1989 Pisa, Italy (COMAC-BME Concerted Project Characterization and Standardization of PET Instrumentation)  相似文献   
59.
Bacteria from the Brucella genus are able to survive and proliferate within macrophages. Because they are phylogenetically closely related to macrophages, myeloid dendritic cells (DCs) constitute potential targets for Brucella bacteria. Here we report that DCs display a great susceptibility to Brucella infection. Therefore, DCs might serve as a reservoir and be important for the development of Brucella bacteria within their host.  相似文献   
60.
The degree of O2 saturation and different data of acid-base status are determined from pO2, pH, and pCO2 values bya programmable pocket calculator. Since the operating program should be usable for different species and also in the range of very low O2 saturations, obviously the usual Hill equation for calculating the oxygen dissociation curve of hemoglobin is not applicable; the same is true is some cases for the Adair equation. Thus a 3-fold subdivision of the dissociation curve was undertaken and programmed. Suitable programs for several species could be established despite the limited number of program steps in the new calculator, giving systematic deviations in calculated O2 saturations of less than or equal to +/- 0.9 saturation precent over the full range of dissociation curves. A reverse procedure for calculation of pO2 from saturation is added. In situations where pCO2 or base excess are not known or only estimated, limits of the arising error are stated. In the acid-base program 7 parameters are evaluated partially using empirical formulae derived from nomograms. The programmable pocket calculator offers advantages of small size, economy, and independence of line voltage compared to much more spacious units and a precision equal or superior to nomograms.  相似文献   
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