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141.
The gate bias dependence of the field-effect mobility in pentacene-based insulated gate field-effect transistors (IGFETs) was interpreted on the basis of the interaction of charge carriers with localized trap levels in the band gap. This understanding was used to design and fabricate IGFETs with mobility of more than 0.3 square centimeter per volt per second and current modulation of 10(5), with the use of amorphous metal oxide gate insulators. These values were obtained at operating voltage ranges as low as 5 volts, which are much smaller than previously reported results. An all-room-temperature fabrication process sequence was used, which enabled the demonstration of high-performance organic IGFETs on transparent plastic substrates, at low operating voltages for organic devices.  相似文献   
142.
Genome-sequencing studies indicate that all humans carry many genetic variants predicted to cause loss of function (LoF) of protein-coding genes, suggesting unexpected redundancy in the human genome. Here we apply stringent filters to 2951 putative LoF variants obtained from 185 human genomes to determine their true prevalence and properties. We estimate that human genomes typically contain ~100 genuine LoF variants with ~20 genes completely inactivated. We identify rare and likely deleterious LoF alleles, including 26 known and 21 predicted severe disease-causing variants, as well as common LoF variants in nonessential genes. We describe functional and evolutionary differences between LoF-tolerant and recessive disease genes and a method for using these differences to prioritize candidate genes found in clinical sequencing studies.  相似文献   
143.
A 10 year research programme at Lincoln University, investigating the use of Trichoderma species for biological control of soil-borne diseases of vegetable crops, has resulted in the development of two commercial products. Trichodry TM. 6S and Trichoflow TM. 6S based upon Trichoderma hamatum isolate 6SR4, are used to control Sclerotinia lettuce drop disease. The Trichodry 6S product is formulated as a dry flake, which is incorporated into nursery seedling mix and the Trichoflow 6…  相似文献   
144.
Parabiont rat pairs with a skin-vascular anastomosis were used to test for a radiation-induced transferable humoral factor which would motivate aversive conditioning in a nonirradiated (shielded) recipient. The shielded partner, by tasting saccharinflavored fluid shortly after its partner was x-irradiated (360 roentgens), was aversively conditioned to saccharin. This was interpreted as evidence for a humoral motivating factor.  相似文献   
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The acute haemodynamic and metabolic repercussions of total venous inflow occlusion were evaluated in six normal dogs, each of which underwent two four minute occlusions and one eight minute occlusion at normothermia. A further three dogs underwent a single eight minute period of occlusion and were allowed to recover from anaesthesia. Total venous inflow occlusion was well tolerated by all animals. They remained in sinus rhythm at the completion of occlusion, and unassisted haemodynamic recovery occurred rapidly. Recovery was quicker after four minutes than after eight minutes. There was no clinically detectable neurological impairment in three dogs which were allowed to recover.  相似文献   
150.
A fluorochrome microassay was used to investigate peripheral blood polymorphonuclear leukocyte (PMNL) function in cattle. Glass-adherent PMNL were reacted withStaphylococcus aureus princubated in 20% bovine serum for 30, 60 and 90 min. Coverslips were stained with acridine organge (AO) followed by crystal violet to quench extracellular bacterial fluorescence. PMNL function was evaluated by counting the number of dead (stained red with AO) and live (stained green with AO)S. aureus contained within 100 PMNL. A phagocytic index was calculated as the average number of bacteria contained within PMNL. The percentage killing ofS. aureus was calculated from the average proportion ofS. aureus within PMNL that were dead.Six clinically normal Holstein calves, 3–4 months of age, were sampled on 6 consecutive days. PMNL phagocytosis and killing did not vary significantly (p>0.05) among repeated samplings per calf. PMNL function increased with increasing time of incubation of PMNL withS. aureus. Means (± SD) for percentage killing were 46.7±13.1, 57.4±11.6, and 62.1±9.8% for 30, 60 and 90 min of reaction, respectively. Means (± SD) for the phagocytic index were 2.9±0.8, 3.6±1.0, and 4.2±1.1 bacteria/PMNL for 30, 60 and 90 min of reaction, respectively. PMNL function was determined in 30 normal cattle of various breeds, age and sex, and these values were pooled to provide normal values for PMNL function.When values for bovine clinical patients (n=25) with various diagnoses were compared with normal values (defined by the mean ± 2SD for the 30 normal cattle) for PMNL function, only one patient was observed to exhibit PMNL hypofunction. A cow with disseminated intravascular coagulation in association with peracute coliform mastitis exhibited decreased PMNL killing capacity. Abnormal PMNL function was uncommon in the hospital population studied.Peripheral blood PMNL function was evaluated in lactating Holstein cows with (n=15) or without (n=15) chronic subclinicalS. aureus mastitis. There was no significant (p>0.05) difference in PMNL function among these cows.  相似文献   
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