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71.
The article reports numerical simulation for the system combining selective adsorption of fructose and an enzyme reaction to produce higher fructose syrup. A procedure for the dynamic simulation of the process in the frame of equations for mass transfer in fixed bed, is obtained by making a solute material balance. A fixed bed model incorporating axial dispersion and a linear driving force for mass transfer was successfully used to estimate optimum operating conditions (switch times and fluid flow rates)  相似文献   
72.
From November 1972 to November 1975, 52 males and 39 females aged 11 to 71 years were trained for home peritoneal dialysis. Dialysis was performed through a permanent catheter 4 nights a week. The first 11 patients used the manual system, exchanging 2 / of dialysate solution every 50 to 60 minutes. Subsequently 73 patients used the automatic cycler and commercially available dialysate and 7 patients used Tenckhoff''s reverse osmosis peritoneal dialysis machine. The average duration of training was 15, 11.6 and 15 dialysis days, respectively, for the three methods. For the 83 patients followed up, the average duration of home dialysis was 8.3 months (range, 0.5 to 33 months); the total number of dialyses at home was 10 571. Ten received a transplant, 20 were transferred to hospital peritoneal dialysis or hemodialysis, 8 died and 48 continued with home dialysis. Twenty-three patients had a total of 33 episodes of peritonitis, an incidence of 27.7% among the patients in the program for up to 3 years or 0.3% among all the dialyses. By November 1975, 46 patients had returned to their predialysis lifestyle, 18 were working part-time, 10 were able to work but were not doing so, and 9 were unable to work or care for themselves.  相似文献   
73.
Using GPS telemetry and ear tagging, we monitored wild boar sounder (a 2-year sow, a female yearling and eight piglets) captured in northern Slovenia. Five months after the capture, the sounder left its home range and first travelled 100 km west, to the three-border area between Slovenia, Austria and Italy, and from there toward southeast. The sow and three piglets were shot 2 months after start of dispersal 60 km from the capture site and in-between travelled at least 500 km. At least one piglet continued dispersal after the death of the sow, and the yearling split from the sounder during dispersal. This is the first documented case of long-distance dispersal of adult female wild boar with piglets. Several arguments suggest that long-distance dispersal of female wild boar is more common than previously reported in the literature. For wild boar and other species with predominant male dispersal, data on occasional far-dispersing females like presented here are important for understanding biology of species (e.g. metapopulations, rate of population expansion, local sex and age structure of population) and for management including control of diseases.  相似文献   
74.

Background

Invariant NKT (iNKT) cells are regulatory lymphocytes that may be important in disorders with increased Th1 responses. We utilized a 4-year longitudinal observational study of iNKT cells and SLAM signaling pathway factors, which are important for iNKT development in patients with newly diagnosed sarcoidosis.

Methods

Detailed clinical, functional, and radiographic evaluation and determination of iNKT peripheral blood cell counts and expression of SLAM signaling factors was carried out at presentation and after 3 months, 1 year, and 4 years of disease follow-up in 29 patients with pulmonary sarcoidosis. At presentation, we also evaluated the frequencies of pulmonary BALF iNKT cells. We also included 37 control subjects.

Results

We demonstrated a marked deficiency of blood and lung iNKT cells and decreased expression of SLAM signaling factors in patients with newly diagnosed sarcoidosis. During 4 years of disease follow-up, there was a significant increase in blood iNKT cell numbers and in expression of SLAM signaling factors, mainly SLAMF1, SLAMF6, and FYN. This increase clearly correlated with improvement in patients’ clinical symptoms. At the 4-year endpoint, the disease had gone into remission in the great majority of patients and thus also iNKT cell deficiency. Moreover, at the 4-year endpoint iNKT level reached the iNKT level of the control subjects.

Conclusions

Our longitudinal study showed that a disposal of iNKT deficiency in parallel with an increase in expression of SLAM signaling factors characterizes the clinical remission of sarcoidosis.  相似文献   
75.
Transcriptional activity and substrate recognition of cyclin T2 from P-TEFb   总被引:1,自引:0,他引:1  
Kurosu T  Zhang F  Peterlin BM 《Gene》2004,343(1):173-179
  相似文献   
76.
77.
Lactobacillus gasseri LF221 and K7 — from isolation to application   总被引:1,自引:0,他引:1  
The article presents research findings on two human strains with probiotic activity. On the basis of API 50 CHL fermentation pattern, PCR by species-specific primers and sequencing of the V2–V3 region of 16S rRNA both strains designated as LF221 and K7 were identified as members of the Lactobacillus gasseri species. Two LF221 bacteriocins, acidocin LF221 A and B were purified and sequenced. They were classified as members of the two-component class II bacteriocins. Among basic probiotic properties, the survival under conditions in gastro-intestinal tract, ability to adhere to cultured intestinal enterocytes and pig’s mucosa and stimulation of the immune response were demonstrated. In in vivo study of 24 weaned piglets, the survival rate of K7 Rifr and LF221 Rifr was quantified by selective enumeration on MRS agar with rifampicin. The survival of both strains was good (2.9 × 105 cfu of K7 Rifr /g faeces; 4.8 × 105 cfu of LF221 Rifr /g) and the LF221 Rifr /K7 Rifr viable cells were found either in the mucosa of duodenum, jejunum or in the ileum. The possible effect of K7 to inhibit adhesion of E. coli O8:K88 to enterocytes was studied on Caco-2 cultured cells, on tissue obtained from small intestines of pigs and in vivo on gnotobiotic piglets. Lactobacilli were found to be effective in reducing E. coli adhesion to enterocytes in Caco-2 model, but not on mucosa of pig’s jejunum under ex vivo conditions. Competitive exclusion, production of organic acids and stimulation of immune response, were involved in inhibition of E. coli by K7 strain in gnotobiotic piglets. Any inflammatory change in intestines of piglets treated with K7 was observed, which confirmed its safe use. Among the technological parameters the survival and activity of the strains during cheese-making are presented. Presented at the Second Probiotic Conference, Košice, 15–19 September 2004, Slovakia.  相似文献   
78.
One hundred and ten UTI Escherichia coli strains, from Ljubljana, Slovenia, were analyzed for antibiotic resistances, mobile DNA elements, serotype, and phylogenetic origin. A high prevalence of drug resistance and multidrug resistance was found. Twenty-six percent of the isolates harbored a class 1 integron, while a majority of the strains (56%) harbored rep sequences characteristic of F-like plasmids. int as well as rep sequences were found to be distributed in a random manner among strains of the four major phylogenetic groups indicating that all groups have a similar tendency to acquire and maintain mobile genetic elements frequently associated with resistance determinants.  相似文献   
79.
The complete mitochondrial DNA (mtDNA) genome of the Eunapius subterraneus (Porifera, Demospongiae), a unique stygobitic sponge, was analyzed and compared with previously published mitochondrial genomes from this group. The 24,850 bp long mtDNA genome is circular with the same gene composition as found in other metazoans. Intergenic regions (IGRs) comprise 24.7% of mtDNA and are abundant with direct and inverted repeats and palindromic elements as well as with open reading fames (ORFs) whose distribution and homology was compared with other available mt genomes with a special focus on freshwater sponges. Phylogenetic analyses based on concatenated amino acid sequences from 12 mt protein genes placed E. subterraneus in a well-supported monophyletic clade with the freshwater sponges, Ephydatia muelleri and Lubomirskia baicalensis. Our study showed high homology of mtDNA genomes among freshwater sponges, implying their recent split.  相似文献   
80.
It is known that cobalamin (Cbl) deficiency damages myelin by increasing tumor necrosis factor (TNF)-α and decreasing epidermal growth factor (EGF) levels in rat central nervous system (CNS), and affects the peripheral nervous system (PNS) morphologically and functionally. It is also known that some polyneuropathies not due to Cbl deficiency are connected with increased TNF-α levels, and that various cytokines (including TNF-α) and growth factors regulate the in vitro synthesis of normal prions (PrPCs). Given that there is extensive evidence that PrPCs play a key role in the maintenance of CNS and PNS myelin, we investigated whether the PrPC octapeptide repeat (OR) region is involved in the pathogenesis of rat Cbl-deficient (Cbl-D) polyneuropathy. After intracerebroventricularly administering antibodies (Abs) against the OR region (OR-Abs) to Cbl-D rats to prevent myelin damage and maximum nerve conduction velocity (MNCV) abnormalities, and PrPCs to otherwise normal rats to reproduce PNS Cbl-D-like lesions, we measured PrPC levels and MNCV of the sciatic and tibial nerves. PrPC and TNF-α levels were increased in sciatic and tibial nerves of Cbl-D and saline-treated rats, and the OR-Abs normalized the myelin ultrastructure, TNF-α levels, and MNCV values of the sciatic and tibial nerves of Cbl-D rats. The same peripheral nerves of the otherwise normal PrPC-treated rats showed typical Cbl-D myelin lesions, significantly increased TNF-α levels, and significantly decreased MNCV values. These findings demonstrate that Cbl deficiency induces excess PrPCs and thereby excess OR regions, which seem to be responsible for the PNS myelin damage, as has recently been found in the case of CNS myelin damage [66]. Furthermore, excess TNF-α is also involved in the pathogenesis of Cbl-D polyneuropathy. In conclusion, we have extended the list of prion diseases by adding one caused by excess PrPCs and the polyneuropathies related to excess TNF-α.  相似文献   
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