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21.
Kummrow M Meli ML Haessig M Goenczi E Poland A Pedersen NC Hofmann-Lehmann R Lutz H 《Clinical and diagnostic laboratory immunology》2005,12(10):1209-1215
To determine the prevalence of antibodies to feline coronavirus (FCoV) serotypes 1 and 2 in Switzerland and their association with different disease manifestations, a serological study based on immunofluorescence tests was conducted with Swiss field cats using transmissible gastroenteritis virus (TGEV), FCoV type 1 and FCoV type 2 as antigens. A total of 639 serum samples collected in the context of different studies from naturally infected cats were tested. The current study revealed that, with an apparent prevalence of 83%, FCoV serotype 1 is the most prevalent serotype in Switzerland. FCoV type 1 viruses induced higher antibody titers than FCoV type 2, and were more frequently associated with clinical signs and/or feline infectious peritonitis. The antibody development in seven cats experimentally infected with FCoV type 1 revealed that, with progressing duration of infection, antibodies to FCoV type 1 significantly increased over those to FCoV type 2. There was a significant relationship between antibody titers against TGEV, FCoV 1, and FCoV 2 and TGEV antigen detected the highest proportion of seropositive cats. We conclude that a vaccine against FCoV should be based on FCoV type 1-related antigens and that for serodiagnosis of FCoV infection TGEV should be used to attain the highest diagnostic efficiency. When serology is used in addition to clinical signs, hematology, and clinical chemistry results as an aid to diagnose clinical FIP, TGEV shows a diagnostic efficiency equal to that of a FCoV antigen. 相似文献
22.
Doctors'' characteristics do not predict long-term glycaemic control in type 2 diabetic patients. 下载免费PDF全文
Lars J Hansen Niels de Fine Olivarius Volkert Siersma John Sahl Andersen 《The British journal of general practice》2003,53(486):47-49
Glycaemic control in type 2 diabetic patients varies widely between general practitioners (GPs). To increase our understanding of this variation, linear random effects models were used to examine the predictive value of GP characteristics on the course of annual HbA1c measurements, in 688 newly diagnosed type 2 diabetic patients between one and five years after diabetes diagnosis. We found that characteristics of centrally supported GPs, such as interest in diabetes, experience, practice type, list size, and weekly working hours, did not predict their patients' glycaemic control. 相似文献
23.
Glucose Ingestion Attenuates Interleukin-6 Release from Contracting Skeletal Muscle in Humans 总被引:8,自引:1,他引:8
Mark A. Febbraio Adam Steensberg Charlotte Keller Rebecca L. Starkie Henning B. Nielsen Peter Krustrup Peter Ott Niels H. Secher Bente K. Pedersen 《The Journal of physiology》2003,549(2):607-612
To examine whether glucose ingestion during exercise affects the release of interleukin-6 (IL-6) from the contracting limb, seven men performed 120 min of semi-recumbent cycling on two occasions while ingesting either 250 ml of a 6.4 % carbohydrate (GLU trial) or sweet placebo (CON trial) beverage at the onset of, and at 15 min intervals throughout, exercise. Muscle biopsies obtained before and immediately after exercise were analysed for glycogen and IL-6 mRNA expression. Blood samples were simultaneously obtained from a brachial artery and a femoral vein prior to and during exercise and leg blood flow was measured by thermodilution in the femoral vein. Net leg IL-6 release, and net leg glucose and free fatty acid (FFA) uptake, were calculated from these measurements. The arterial IL-6 concentration was lower ( P < 0.05 ) after 120 min of exercise in GLU, but neither intramuscular glycogen nor IL-6 mRNA were different when comparing GLU with CON. However, net leg IL-6 release was attenuated ( P < 0.05 ) in GLU compared with CON. This corresponded with an enhanced ( P < 0.05 ) glucose uptake and a reduced ( P < 0.05 ) FFA uptake in GLU. These results demonstrate that glucose ingestion during exercise attenuates leg IL-6 release but does not decrease intramuscular expression of IL-6 mRNA. 相似文献
24.
Niels Marcussen Peter D. Ottosen Sten Christensen 《Virchows Archiv : an international journal of pathology》1990,417(6):513-522
Summary The very heterogeneous population of glomeruli in rats with lithium-induced chronic nephropathy which includes small glomeruli without connection to a proximal tubule (atubular glomeruli) and large hypertropic glomeruli with connection to a normal proximal tubule, was studied at the ultrastructural level, using stereological methods. After 8 weeks of lithium treatment followed by 8 weeks without lithium the hypertrophic glomeruli showed no changes in their relative ultrastructural composition, including normal mesangium, basement membrane-like material and peripheral basement membrane. The absolute quantities of each component were, however, increased due to the increased volume of the glomeruli. The atubular glomeruli had increased volume fractions of mesangium, peripheral basement membrane, basement membrane-like material and epithelium, whereas the absolute quantities were decreased due to the decreased volume. The thickness of the basement membrane was within normal limits in the group of hypertrophic glomeruli but increased by 31% above controls in the group of atubular glomeruli. Both groups of glomeruli in lithium-treated animals showed normal mean foot process width, but with a slightly abnormal distribution. The atubular glomeruli showed a disproportionate large decrease in peripheral filtration surface and capillary length, compared with the reduction in glomerular volume, whereas the hypertrophic glomeruli showed changes in proportion with the increased volume. 相似文献
25.
Early prenatal diagnosis; A study of biopsy techniques and cell culturing from extraembryonic membranes 总被引:2,自引:0,他引:2
The study concerns the diagnosis of fetal condition early in pregnancy - within the first trimester. An instrument was designed to allow biopsy of the extraembryonic membranes under visual control. The instrument was tested in 95 pregnant women prior to legal termination of pregnancy. In 28 cases, the biopsies were taken in the outpatient clinic and the patients were observed for 8 d before the pregnancy was terminated. Thirty-eight percent of the biopsies were successful. Causes of failure were puncture or biopsy of the amniotic membrane, and bleeding which obscured vision. Biopsies were nonetheless obtained in all but four cases, and 60% contained chorionic villi. Target biopsy of chorion as chorionic villi is, however, possible, and the optimal time seems to be in the tenth week of pregnancy. Culture of biopsy material and karyotyping was successful in virtually all instances. When fetal tissue was identified in the abortion products, and cultured after subsequent termination (24 instances) karyotype determination confirmed the finding from biopsy culture cells. No maternal complications followed the procedure. The possibility is discussed that the present approach may be developed for clinical use as an alternative to transabdominal amniocentesis in the 15th. week. 相似文献
26.
Intrarenal oxygen tension measured by a modified Clark electrode at normal and low blood pressure and after injection of x-ray contrast media 总被引:3,自引:0,他引:3
P. Liss Anders Nygren Niels P. Revsbech H. R. Ulfendahl 《Pflügers Archiv : European journal of physiology》1997,434(6):705-711
The oxygen tension (pO2) in the rat kidney was studied using a Clark microelectrode with a guard cathode behind the sensing cathode. The mean (±
SEM) outer tip diameter of the electrodes used was 5.5 ± 1.9 μm. The zero-pO2 current amounted to 12.5 ± 0.9 pA at 37°C; at air saturation it was 252 ± 22.9 pA. Rats with a systolic blood pressure (BP)
above 80 mmHg (where 1 mmHg = 133 Pa) showed an average pO2 in the cortex of 45 ± 2 mmHg and in the outer medulla of 31 ±1 mmHg. In rats with a BP below 80 mmHg a paradoxically high
outer medullary pO2 of 40 ± 4 mmHg was found, while the pO2 in the cortex was 27 ± 4 mmHg. Changes in pO2 were also noted in the renal cortex and outer medulla after intravenous injections of the x-ray contrast medium diatrizoate
(370 mg iodine/ml). In rats with normal BP, injection of diatrizoate caused a slight fall in pO2 in the renal cortex, from 42 ± 4 to 38 ±4 mmHg. In the medulla pO2 decreased significantly from 34 ± 6 to 20 ±4 mmHg. Ringer’s solution did not induce any changes.
Received: 9 September 1996 / Received after revision: 22 May 1997 / Accepted: 23 May 1997 相似文献
27.
Maya Kummrow Marina L. Meli Michael Haessig Enikoe Goenczi Amy Poland Niels C. Pedersen Regina Hofmann-Lehmann Hans Lutz 《Clinical and Vaccine Immunology : CVI》2005,12(10):1209-1215
To determine the prevalence of antibodies to feline coronavirus (FCoV) serotypes 1 and 2 in Switzerland and their association with different disease manifestations, a serological study based on immunofluorescence tests was conducted with Swiss field cats using transmissible gastroenteritis virus (TGEV), FCoV type 1 and FCoV type 2 as antigens. A total of 639 serum samples collected in the context of different studies from naturally infected cats were tested. The current study revealed that, with an apparent prevalence of 83%, FCoV serotype 1 is the most prevalent serotype in Switzerland. FCoV type 1 viruses induced higher antibody titers than FCoV type 2, and were more frequently associated with clinical signs and/or feline infectious peritonitis. The antibody development in seven cats experimentally infected with FCoV type 1 revealed that, with progressing duration of infection, antibodies to FCoV type 1 significantly increased over those to FCoV type 2. There was a significant relationship between antibody titers against TGEV, FCoV 1, and FCoV 2 and TGEV antigen detected the highest proportion of seropositive cats. We conclude that a vaccine against FCoV should be based on FCoV type 1-related antigens and that for serodiagnosis of FCoV infection TGEV should be used to attain the highest diagnostic efficiency. When serology is used in addition to clinical signs, hematology, and clinical chemistry results as an aid to diagnose clinical FIP, TGEV shows a diagnostic efficiency equal to that of a FCoV antigen. 相似文献
28.
29.
Niels Jrgensen Jrn Müller Aleksander Giwercman Jakob Visfeldt Henrik Mller Niels E. Skakkebk 《The Journal of pathology》1995,176(3):269-278
The origin of testicular germ cell tumours occurring during childhood is poorly understood. In adults, the classical seminomas and non-seminomas originate from carcinoma in situ of the testis, which can usually also be detected in seminiferous tubules adjacent to the tumours. In order to contribute with information regarding a possible association between carcinoma in situ and the childhood group of germ cell tumours, we investigated seminiferous tubules adjacent to 13 infantile yolk sac tumours, five infantile teratomas, and six adolescent germ cell tumours of various types, using morphological evaluation, immunohistochemical staining with markers for carcinoma in situ cells, and densitometric DNA measurement of the germ cells. We detected clear differences between the germ cell populations adjacent to adolescent and infantile germ cell tumours. The former were associated with both normal germ cells and carcinoma in situ cells. The presence of carcinoma in situ cells strongly suggested that the adolescent tumours arose from carcinoma in situ cells, like germ cell tumours occurring in adult men. Although we were in doubt in two cases, the infantile germ cell tumours were in general not associated with carcinoma in situ cells. The aetiology of infantile yolk sac tumours and teratomas may therefore be fundamentally different from that of adolescent and adult germ cell tumours. The origin of yolk sac tumours and teratomas remains to be elucidated. 相似文献
30.
Niels Decher reas S. Barth Teresa Gonzalez Klaus Steinmeyer Michael C. Sanguinetti 《The Journal of physiology》2004,557(3):761-772
Kv4.3 channels conduct transient outward K+ currents in the human heart and brain where they mediate the early phase of action potential repolarization. KChIP2 proteins are members of a new class of calcium sensors that modulate the surface expression and biophysical properties of Kv4 K+ channels. Here we describe three novel isoforms of KChIP2 with an alternatively spliced C-terminus (KChIP2e, KChIP2f) or N-terminus (KChIP2g). KChIP2e and KChIP2f are expressed in the human atrium, whereas KChIP2g is predominantly expressed in the brain. The KChIP2 isoforms were coexpressed with Kv4.3 channels in Xenopus oocytes and currents recorded with two-microelectrode voltage-clamp techniques. KChIP2e caused a reduction in current amplitude, an acceleration of inactivation and a slowing of the recovery from inactivation of Kv4.3 currents. KChIP2f increased the current amplitude and slowed the rate of inactivation, but did not alter the recovery from inactivation or the voltage of half-maximal inactivation of Kv4.3 channels. KChIP2g increased current amplitudes, slowed the rate of inactivation and shifted the voltage of half-maximal inactivation to more negative potentials. The biophysical changes induced by these alternatively spliced KChIP2 proteins differ markedly from previously described KChIP2 proteins and would be expected to increase the diversity of native transient outward K+ currents. 相似文献