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891.
The effect of Leucaena leucocephala hybrid-Bahru (LLB), which contains a high concentration of condensed tannins, on cellulolytic rumen fungal population in goats was investigated using real-time PCR. The fungal population in goats fed LLB was inhibited during the first 10 days of feeding, but after 15 days of feeding, there was a tremendous increase of fungal population (157.0 μg/ml), which was about fourfold more than that in control goats (39.7 μg/ml). However, after this period, the fungal population decreased continuously, and at 30 days of feeding, the fungal population (50.6 μg/ml) was not significantly different from that in control goats (55.4 μg/ml).  相似文献   
892.
As part of a continuing epidemiological study of non-insulin dependent diabetes among Pima Indians 154 subjects who had had a transient impairment of glucose tolerance were followed up for 1.2-16.9 (median 5.8) years after their glucose tolerance had returned to normal. Of these, 49 subsequently developed diabetes; 26 subsequently developed impaired glucose tolerance; and 79 had normal glucose tolerance at the last examination. The cumulative incidence of diabetes was 16% and 48% at five and 10 years of follow up respectively, compared with 3% and 8% for a control group of 1245 members of the same population. After adjustment for age, sex, body mass index, and plasma glucose concentration two hours after glucose loading the incidence of diabetes among the subjects who had had transient impaired glucose tolerance was 3.0 times that among the controls (95% confidence interval 2.1 to 4.3). Proportional hazards function analysis indicated that obesity was the most important predictor of subsequent development of diabetes. The results suggest that transient impairment of glucose tolerance indicates, at least in some subjects, a predisposition to diabetes and should not be considered clinically unimportant.  相似文献   
893.
894.
The spermicidal efficacy of synthetic peptides, dermaseptin (DS1) and (DS4), was studied under in vitro conditions using human spermatozoa. The data showed that sperm motility was inhibited with various concentrations of dermaseptins at different intervals ranging from 2 to 240 min. The effective 100% inhibitory concentration (EC100) of DS4 sperm immobilization assay was equal to 50 mg/ml at 30 min, while the EC 100 of DS1 was equal to 100 mg/ml. The presence of 0.1% of chelating agent, EDTA, reduced the EC100 of DS4 to 5 mg/ml, while less than a twofold enhancement in DS 1 activity was observed in combination with EDTA. The action of dermaseptins on sperm motility was observed to be dose-dependent. Addition of pentoxifylline, which is known to enhance sperm motility, and Ca2+, which is a key element for sperm movement, did not prevent the spermicidal action of dermaseptins.  相似文献   
895.
Solar cells become a viable energy source to charge lithium ion batteries. Here a simple and efficient photocharging design approach is demonstrated, where a promising low cost single junction solar cell such as perovskite solar cell or dye sensitized solar cell efficiently charges a Li4Ti5O12‐LiCoO2 Li‐ion cell using a DC–DC voltage boost converter. The converter boosts the low input voltage of a single junction solar cell to charge a lithium ion cell and offers advantages including maximum power point tracking of solar photovoltaics and overvoltage protection for the lithium ion cell. This is the first demonstration of this technology. This approach leads to the highest reported overall efficiency of 9.36% and average storage efficiency of 77.2% at 0.5 C discharge for a perovskite solar cell‐converter charging. The high efficiency for the perovskite solar cell‐converter charging is attributed to maximum power harvesting along with high power conversion efficiency of the perovskite solar cell and low potential polarization between the charge and discharge voltage plateaus for the Li4Ti5O12‐LiCoO2 Li‐ion cell.  相似文献   
896.
897.
The combination of seminal vesicle cyst and homolateral renal agenesis is a rare congenital anomaly. However, this anomaly is diagnosed more frequently due to progress in medical imaging. The authors report three cases of seminal vesicle cyst associated with ipsilateral renal agenesis in two cases and ectopic ureter in one case. All cases presented nonspecific clinical symptoms. The diagnosis was suspected on imaging (ultrasound and computed tomography). Treatment was surgical in two cases and endoscopie in one case. The authors review the literature on the aetiology and pathogenesis of seminal vesicle cyst, its association with homolateral renal agenesis and diagnostic and therapeutic methods.  相似文献   
898.
899.
The natural capacity of plants to endure salt stress is largely regulated by multifaceted structural and physio-biochemical modulations. Salt toxicity endurance mechanism of six ecotypes of Typha domingensis Pers. was evaluated by analyzing photosynthesis, ionic homeostasis, and stomatal physiology under different levels of salinity (0, 100, 200 and 300 mM NaCl). Typha populations were collected across different areas of Punjab, an eastern province in Pakistan. All studied attributes among ecotypes presented differential changes as compared to control. Different salt treatments not only affected gas exchange attributes but also shown significant modifications in stomatal anatomical changes. As compared to control, net photosynthetic rate, transpiration rate, total chlorophyll contents and carotenoids were increased by 111%, 64%, 103% and 171% respectively, in Sahianwala ecotype among all other ecotypes. Similarly, maximum water use efficiency (WUE), sub stomatal CO2 concentration, sodium (Na+) and chloride (Cl) contents were observed in Sahianwala (191%, 93%, 168%, 158%) and Knotti (162%, 75%, 146%, 182%) respectively, as compared to the others ecotypes. Adaxial and abaxial stomatal areas remained stable in Sahianwala and Knotti. The highest abaxial stomatal density was observed in Gatwala ecotype (42 mm2) and maximum adaxial stomatal density was recorded in Sahianwala ecotype (43 mm2) at 300 mM NaCl salinity. The current study showed that Typha ecotypes responded varyingly to salinity in terms of photosynthesis attributes to avoid damages due to salinity. Overall, differential photosynthetic activity, WUE, and changes in stomatal attributes of Sahianwala and Knotti ecotypes contributed more prominently in tolerating salinity stress. Therefore, Typha domingensis is a potential species to be used to rehabilitate salt affected lands for agriculture and aquatic habitat.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00963-x.  相似文献   
900.

Background  

We have recently shown that serum relaxin-2 levels are attenuated in women with a history of recurrent pregnancy loss (RPL). We sought to determine whether a history of RPL is also associated with changes in serum matrix metalloproteases (MMPs) and tissue inhibitors of matrix metalloproteases (TIMP) -1 and -2.  相似文献   
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