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91.
Autophagy is a highly regulated and evolutionarily conserved process of cellular self-digestion. Recent evidence suggests that this process plays an important role in regulating T cell homeostasis. In this study, we used Rag1(-/-) (recombination activating gene 1(-/-)) blastocyst complementation and in vitro embryonic stem cell differentiation to address the role of Beclin 1, one of the key autophagic proteins, in lymphocyte development. Beclin 1-deficient Rag1(-/-) chimeras displayed a dramatic reduction in thymic cellularity compared with control mice. Using embryonic stem cell differentiation in vitro, we found that the inability to maintain normal thymic cellularity is likely caused by impaired maintenance of thymocyte progenitors. Interestingly, despite drastically reduced thymocyte numbers, the peripheral T cell compartment of Beclin 1-deficient Rag1(-/-) chimeras is largely normal. Peripheral T cells displayed normal in vitro proliferation despite significantly reduced numbers of autophagosomes. In addition, these chimeras had greatly reduced numbers of early B cells in the bone marrow compared with controls. However, the peripheral B cell compartment was not dramatically impacted by Beclin 1 deficiency. Collectively, our results suggest that Beclin 1 is required for maintenance of undifferentiated/early lymphocyte progenitor populations. In contrast, Beclin 1 is largely dispensable for the initial generation and function of the peripheral T and B cell compartments. This indicates that normal lymphocyte development involves Beclin 1-dependent, early-stage and distinct, Beclin 1-independent, late-stage processes.  相似文献   
92.
The aim of this study was to present our experiences in diagnosing spondyloarthritides (SpA), and to list the most common clinical features of HLA-B27 positive patients. The study included 65 HLA-B27 positive patients with confirmed diagnosis of ankylosing spondylitis (AS) and psoriatic arthritis (PsA) who were analyzed between 2009 and 2010 in Clinic of Internal Medicine in Osijek. The diagnosis of seronegative spondyloarthritides was based on the ASAS (Assessment in AS Working Group) classification criteria for axial and then supplemented with ASAS criteria for peripheral SpA and was confirmed by radiological techniques. For diagnosing the ankylosing spondylitis (AS), there have been applied the modified New York criteria. Radiological criteria for definite sacroiliitis according to the modified New York criteria is bilateral sacroiliitis, grade 2-4 (> or = 2) or unilateral sacroiliitis, grade 3-4. For diagnosing the psoriatic arthritis (PsA), there were used CASPAR diagnostic criteria. Other features of SpA are defined within the existing classification criteria. HLA-B27 antigen was determined by direct immune-fluorescence technique using flow cytometer. The average age of patients was 50.34 years, of whom 27 female (41.53%), 38 male (58.46%). Duration of illness was 15.79 years on average. With 75.38% of patients, there had been determined the diagnosis of AS; 24.62% of patients had the diagnosis of PsA. The most common clinical characteristics that patients had were: inflammatory back pain (pain Inflammation along the lumbosacral spine), peripheral arthritis, intermittent pain in the gluteus, sacroiliitis, enthesitis, uveitis, dactilitis.  相似文献   
93.
The renin-angiotensin system is involved in the progression of chronic renal disease of both diabetic and nondiabetic origin. The angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers have been demonstrated to reduce urinary protein excretion and attenuate the development of renal injury. This prospective, randomized, 12-month study assessed the effects of ramipril (N = 23) vs. valsartan (N = 22) vs. combination of ramipril and valsartan (N = 26) on proteinuria, renal function and metabolic profile in 71 patients with nondiabetic proteinuria with normal or slightly impaired renal function. Monotherapy with ramipril or valsartan and combination of these two drugs significantly reduced proteinuria, serum creatinine, cholesterol and triglycerides as well as systolic and diastolic arterial blood pressure. There was no significant difference among three study groups according to reduction of arterial blood pressure, serum cholesterol and triglycerides. At one year, a significant reduction in serum creatinine was recorded in all three study groups, whereas at 3 and 6 months a statistically significant reduction in serum creatinine was only observed in patients on combination therapy. In addition, at 3 months the reduction of proteinuria was significantly greater in patients on combination therapy than in those on either monotherapy. These results indicated the combination therapy with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers to be more efficacious than either monotherapy in reducing proteinuria and serum creatinine level in the first 3 (proteinuria and serum creatinine) or 6 (serum creatinine) months of treatment.  相似文献   
94.
Despite the already established route of chemically catalyzed transesterification reaction in biodiesel production, due to some of its shortcomings, biocatalysts such as lipases present a vital alternative. Namely, it was noticed that one of the key shortcomings for the optimization of the enzyme catalyzed biodiesel synthesis process is the information on the lipase activity in the reaction mixture. In addition to making optimization difficult, it also makes it impossible to compare the results of the independent research. This article shows how lipase intended for use in biodiesel synthesis can be easily and accurately characterized and what is the enzyme concentration that enables achievement of the desired level of fatty acid methyl esters (FAME) in the final product mixture. Therefore, this study investigated the effect of two different activity loads of Burkholderia cepacia lipase on the biodiesel synthesis varying the pH and temperature optimal for lipase activity. The optimal lipase pH and temperature were determined by two different enzyme assays: spectrophotometric and titrimetric. The B. cepacia lipase pH optimum differentiated between assays, while the lipase optimally hydrolyzed substrates at 50°C. The analysis of FAME during 24 hr of biodiesel synthesis, at two different enzyme concentrations, pH 7, 8, and 10, and using two different buffers, revealed that the transesterification reaction at optimal pH, 1 hr reaction time and lipase activity load of 250 U per gram of reaction mixture was sufficient to produce more than 99% FAME.  相似文献   
95.
Interest for breeding mouflons in Europe is growing by the day, so it is important to extend our knowledge regarding their physiology. To establish reference intervals of biochemical values for mouflon (Ovis orientalis musimon), serum samples from 35 males and 26 females were analyzed using the automatic analyzer Olympus AU 640 for 22 serum biochemistry parameters. All mouflons aged from 1 to 4 years were apparently healthy and in good body condition and kept at an average altitude of 87 m (45°4′N, 18°6′E). Obtained results were tested according to age and sex categories by the repeated measurement model with Tukey’s post hoc test. Data showed a significantly higher (P < 0.01) concentration of total serum bilirubin and chloride in adult pregnant female mouflons compared to adult male mouflons. A significantly higher (P < 0.01) value of sodium and a lower (P < 0.01) value of serum phosphate in adult pregnant female mouflons compared to adult male mouflons have been determined. These data provide the baseline information about serum biochemical parameters which can be used to manage the health in mouflons.  相似文献   
96.
A joint analysis of five paternal half-sib Holstein families that were part of two different granddaughter designs (ADR- or Inra-design) was carried out for five milk production traits and somatic cell score in order to conduct a QTL confirmation study and to increase the experimental power. Data were exchanged in a coded and standardised form. The combined data set (JOINT-design) consisted of on average 231 sires per grandsire. Genetic maps were calculated for 133 markers distributed over nine chromosomes. QTL analyses were performed separately for each design and each trait. The results revealed QTL for milk production on chromosome 14, for milk yield on chromosome 5, and for fat content on chromosome 19 in both the ADR- and the Inra-design (confirmed within this study). Some QTL could only be mapped in either the ADR- or in the Inra-design (not confirmed within this study). Additional QTL previously undetected in the single designs were mapped in the JOINT-design for fat yield (chromosome 19 and 26), protein yield (chromosome 26), protein content (chromosome 5), and somatic cell score (chromosome 2 and 19) with genomewide significance. This study demonstrated the potential benefits of a combined analysis of data from different granddaughter designs.  相似文献   
97.
The telescopic denture is one possible solution for prosthetic rehabilitation for a partially dentate arch with few remaining teeth, which is the reason why it is usually considered in elderly patients. The system of double crowns consists of the male component of attachment or patrix, which is cemented to the abutment tooth, and the female component of attachment or matrix, which is the removable part of the restoration. Retention force represents resistance to those forces which tend to separate the partial denture and supporting tissue in the occlusal direction. Its optimal value is 5–9 N per each patrix and it should strictly be between these limits as a stronger or weaker force will endanger the functionality of the denture or damage the supporting tissue of the abutment teeth. Objective: The goal of this study was to establish the exact value of the individual and total retention force of the completed telescopic system. Method: The Bredent dynamometer was used for measuring these values. The study involved measuring the individual force of separation of 50 patrix–matrix components, and total force of 20 partial dentures of various designs retained by double crowns made in the Dental Laboratory of the Clinic for Prosthetic Dentistry, Faculty of Stomatology, Belgrade University. The research was carried out in the period from January 2006 to October 2006. Results and conclusion: The results showed different values of separation force – from very low values to those exceeding optimal limits. A reduction in the force of separation is necessary in the case of excessive tightness. If there was looseness between patrix and matrix, the cylindrical components of double crowns need to be lined by a suitable composite material.  相似文献   
98.
Previous studies have shown that in developing monkey corticostriatal fibres terminate around striatal cytoarchitectonic compartments--cell islands, showing transfiguration around 105th embryonic day (E105) of gestation. In the present study we have analyzed these striatal cytoarchitectonic islands and acetylcholinesterase (AChE) rich patches in the developing human brain considering them as structural indicators of the development of the corticostriatal pathways. Postmortal brain tissue of 27 fetuses and prematurely born infants, ranging from 11-34 postovulatory weeks (POW) whose deaths were attributed to non neurological causes, were processed by Nissl method, AChE histochemistry and imunocytochemical technique (synaptophysin). All specimens are part of the Zagreb Neuroembryological Collection. Initial AChE patches, presumably corresponding to the dopaminergic islands, were seen as early as 10 POW whereas cytoarchitectonical cell islands were not observed until 14 POW The main developmental change occurs between 20-24 POW when AChE negative cell poor zones develop around cell islands. This transient AChE pattern of striatal organization reaches its peak around 28 POW being most prominent along lateral border of putamen. In one case of periventricular hemorrhagic lesion with premortem survival period we have found reorganization of AChE patches in the putamen which indicates structural plasticity of corticostriatal pathways. In conclusion we propose that cell poor zones serve as waiting compartments for growing corticostriatal fibers which approach striatum through subcallosal bundle and external capsule. The period of the existence of striatal compartments (14-30 POW) is a sensitive period for structural plasticity and vulnerability after periventricular lesions.  相似文献   
99.
We present a case of 77 years old male with suspected giant cell arteritis. With anamnesis, physical examination, immunological tests, Colour Doppler ultrasonography of superficial temporal artery and finally with patohistological analysis of temporal artery biopsy, we came to right diagnosis.  相似文献   
100.
The main goal of our work was to evaluate advantages and disadvantages of virtual endoscopy (VE) techniques in routinely diagnostic and preoperative management of patients with various sinus diseases or head traumas in our practice. Fly-through algorithm was performed using an Xeon based workstation on data sets created from axial CT images acquired from 320 patients with various paranasal sinus disorders. Images were created using Siemens Somatom Emotion 16 continiously rotating helical CT scanner and archived in DICOM format. In comparison with real endoscopy, the VE has several advantages. It is completely non-invasive. It is possible to repeat the same procedure several times, therefore it may be a valuable tool for training. Interactive control of all virtual camera parameters, including the field-of-view is possible. Endoscopic viewing as opposed to real endoscopy is not restricted to the spaces defined by inner surfaces. The viewer may penetrate the walls and see the extent of lesions within and beyond the wall as well as the adjacent anatomic structures. Virtual endoscopy also has a potential to stage tumors by determining the location and the extent of transmural extension.  相似文献   
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