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221.
C. Jessen Razi Dmi’el Itzhak Choshniak David Ezra Gernot Kuhnen 《Pflügers Archiv : European journal of physiology》1998,436(5):659-666
The temperatures of the arterial blood and the brain in black Bedouin goats were measured continuously by miniature data
loggers. The animals were either euhydrated or dehydrated to 75–80% of the initial body mass by withholding water for 3–4
days during exposure to intense solar radiation. The daily blood temperature means and maxima of were significantly higher
in dehydration than in euhydration, but 40°C was rarely exceeded even during the hot hours of the day. Selective brain cooling
occurred in euhydration, but its extent was small when blood temperature was below 39.5°C. In dehydration, however, selective
brain cooling was frequent and the standard response when blood temperature exceeded 39°C. We believe that selective brain
cooling contributes to the inhibition of evaporative heat loss, which is the primary cause of the higher blood temperature
in dehydration. Rapid rehydration with cold water induced long-lasting depression of blood temperature. No evidence was found
for mechanisms attenuating the subsequent decrease of brain temperature which occurred a few minutes after the uptake of cold
water.
Received: 9 March 1998 / Received after revision: 22 May 1998 / Accepted: 30 May 1998 相似文献
222.
The present study was done to analyse the time-dependent effects of diabetes on Sertoli cells–spermatogonial stem cells’ (SSCs) network interaction by focusing on glial cell line-derived neurotrophic factor (GDNF) and its special receptors, gfrα1 and c-RET as well as the Bcl-6b. In total, 40 Wistar rats were considered in; control, 20, 45 and 60 days diabetes-induced groups. An experimental diabetes was induced by STZ. The GDNF, gfrα1, c-RET and Bcl-6b expressions were evaluated. The serum level of testosterone, tubular repopulation (RI) and spermiogenesis (SPI) indices, general histological alterations, germ cells, mRNA damage, sperm count and viability were assessed. The diabetes, in a time-dependent manner, diminished mRNA and protein levels of GDNF, gfrα1, c-RET and Bcl-6b versus control group (p < .05), enhanced percentage of seminiferous tubules with negative RI, SPI, and diminished Leydig and Sertoli cells distribution, serum levels of testosterone, sperm count and viability. Finally, the number, percentage of cells and seminiferous tubules with normal mRNA content were significantly (p < .05) diminished. In conclusion, as a new data, we showed that the diabetes by inducing severe mRNA damage and suppressing GDNF, gfrα1, c-RET and Bcl-6b expressions, potentially affects the Sertoli–SSCs’ network and consequently inhibits the SSCs’ self-renewal process. 相似文献
223.
224.
Ng Hui-Teng Heah Cheng-Yong Liew Yun-Ming Mohd Mustafa Al Bakri Abdullah Catleya Rojviriya Hasniyati Md Razi Sebastian Garus Marcin Nabiaek Wojciech Sochacki Ilham Mukriz Zainal Abidin Ng Yong-Sing Agata
liwa Andrei Victor Sandu 《Materials》2022,15(12)
This paper uses polyoxyethylene alkyether sulphate (PAS) to form foam via pre-foaming method, which is then incorporated into geopolymer based on fly ash and ladle furnace slag. In the literature, only PAS-geopolymer foams made with single precursor were studied. Therefore, the performance of fly ash-slag blended geopolymer with and without PAS foam was investigated at 29–1000 °C. Unfoamed geopolymer (G-0) was prepared by a combination of sodium alkali, fly ash and slag. The PAS foam-to-paste ratio was set at 1.0 and 2.0 to prepare geopolymer foam (G-1 and G-2). Foamed geopolymer showed decreased compressive strength (25.1–32.0 MPa for G-1 and 21.5–36.2 MPa for G-2) compared to G-0 (36.9–43.1 MPa) at 29–1000 °C. Nevertheless, when compared to unheated samples, heated G-0 lost compressive strength by 8.7% up to 1000 °C, while the foamed geopolymer gained compressive strength by 68.5% up to 1000 °C. The thermal stability of foamed geopolymer was greatly improved due to the increased porosity, lower thermal conductivity, and incompact microstructure, which helped to reduce pressure during moisture evaporation and resulted in lessened deterioration. 相似文献
225.
Razi E 《Dermatology online journal》2006,12(2):15
A 70-year-old woman with yellow nail syndrome and right-sided pleural effusion, lower extremity edema, and hypoalbuminemia was followed for 18 months. She reported an 8-year history of asthma. She had four children (3 boys and 1 girl). Dystrophy, changes in color and shape of nails both hands and foot, along with lower extremity edema was observed in the daughter and two of her sons. One son had asthma. The patient reported that her grandmother had similar nail abnormality and lower extremity edema. Other family members and patient's grandchildren were healthy. This report demonstrates a case of familial yellow-nail syndrome. 相似文献
226.
Background
The occurrence of Giardia duodenalis in cats is of potential significance from both clinical and public health perspectives. The object of this study was antigenic detection of G. duodenalis in household cats of Ahvaz district, South-West of Iran.Methods
The prevalence of G. duodenalis was determined in fecal samples by two techniques: centrifugation-flotation and a commercial Giardia Antigen Test Kit (immunochromatography assay) in 150 household cats of different ages among referred cases to Veterinary Hospital of Ahvaz University from January 2008 to February 2010.Results
Five out of 150 fecal samples (3.33%) were positive for antigen of G. duodenalis by immunochromatography assay. The prevalence was significantly higher in young cats less than 6 months (15.79%) compared with adult cats 6 months – 3 years (1.37%) (P=0.027) and above 3 years (1.72%) (P=0.044). The infection had more prevalence in diarrheic cats (17.39%) compared with non-diarrheic cats (0.79%) and the difference was significant (P=0.02) as well. The prevalence was higher in male cats (3.41%) than females (3.23%) and in the season of autumn (6.06%), but the difference was not significant between the prevalence of infection relative to host gender and season (P>0.05). Microscopy examination on fecal samples showed that 2% of the studied cats were positive.Conclusion
The parasite antigen was present as a zoonotic infection in Ahvaz district, South-west of Iran. More sensitive techniques, such as immunochromatography assay, might yield more reliable results, in the detection of low levels of Giardia in fecal samples of cats. 相似文献227.
228.
What we have learned from 5 cases of permanent capsule retention 总被引:3,自引:0,他引:3
BACKGROUND: Capsule endoscopy allows the direct visualization of the entire small bowel. There is limited data on the clinical significance of permanent capsule retention. OBJECTIVE: Our purpose was to document the frequency, findings, risk factors, management, and outcomes of permanent capsule retention. DESIGN: Retrospective, case series. SETTING: Single tertiary referral center, outpatient. RESULTS: Permanent capsule retention occurred in 2% of our cases (5/245). The following pathologies caused insufficient capsule passage: adenocarcinoma in a patient with hereditary nonpolyposis colorectal cancer (1), idiopathic stenosis (1), stricturing Crohn's disease (2), and adhesions (1). Capsule retention lead to a symptomatic small-bowel obstruction in only 1 of these cases (0.4%). As a consequence, 2 cases had successful endoscopic retrieval; 3 cases required surgical intervention. Four of 5 patients had a clear clinical benefit resulting from the capsule findings or the secondary procedure. CONCLUSIONS: Permanent capsule retention is rare. Even though this event may lead to the necessity of an endoscopic or surgical intervention, a clear benefit for the patient in respect to the underlying disease resulted in 4 of 5 patients. 相似文献
229.
Nasir Ali Afsar Sierk Haenisch Ahmed Mateen Ahmed Usman Mike Ufer Khwaja Zafar Ahmed Hakimuddin Razi Ahmad Ingolf Cascorbi 《Basic & clinical pharmacology & toxicology》2010,107(1):570-576
Abstract: Polymorphic genes of drug metabolizing enzymes and transporters may influence drug response. With some exemptions, single nucleotide polymorphisms in such genes, however, are not known to be susceptibility factors for breast cancer. This study explored genotype profiles for the breast cancer patients on fluorouracil, doxorubicin and cyclophosphamide (FAC) in a Pakistani set of population and their comparison with HapMap data. Sixty‐eight female breast cancer patients were included. All received FAC chemotherapy. Relevant genotyping was done either through restriction fragment length polymorphism or pyrosequencing. The variant allele frequencies were: 5.1% for CYP2C9*2 (430C>T), 15.4% for CYP2C9*3 (1075A>C), 27.2% for CYP2C19*2 (681G>A), 33.1% for GSTA1*B (‐69C>T, ‐52G>A), 62.5% for ALDH3A1*2 (985C>G), 58.8% and 4.4% for ABCB1 (2677 G>T/A), 64.7% for ABCB1 3435 C>T, and 15.4%, 33.1% and 39.7% for ABCC2 (–24 C>T, 1249 G>A and 3972 C>T). In comparison with HapMap, this first exploration in Pakistani samples shows higher frequency of (i) CYP2C9*3 carriers (p < 0.05) than in Hispanic, Chinese, Japanese and African samples, (ii) ALDH3A1*2 carriers (p < 0.01) than Caucasian, Hispanic, Chinese, Japanese and African samples. For ABC transporters, a higher frequency of variant allele was observed in (iii) ABCB1 2677 G>T/A (p < 0.01) than Caucasian, Hispanic and African, (iv) ABCB1 3435 C>T (p < 0.05) than Chinese, Japanese and African, (v) ABCC2 1249 G>A (p < 0.01) than Hispanic, Chinese and Japanese samples. In conclusion, cyclophosphamide activation and detoxification of reactive intermediates may be altered in the Pakistani. Though carriers of CYP2C19*2 were higher than in Caucasian and Hispanics, they did not reach statistical significance (p = 0.05). 相似文献
230.