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51.
Analysis of masticatory function is the basis of clinical work in almost all fields of dentistry. Bite forces are the expression and measure of masticatory function. Physical training has an effect on the development of functional ability, motoric ability of the organism and the formation of desired physical proportions. The purpose of this study was to examine the association between physical fitness and bite force values. Because of strictly defined regulations in the army with regard to training and nutrition, Croatian Army recruits were ideal examinees for this examination. The examinees were 135 recruits. Bite forces were measured on three places (area of the central incisors, left and right in the area of the first molars) before and after three-months of training. Of all the examinees, 108 had increased their body weight, 12 had decreased it and 15 had not changed their body weight. The median of measured forces in the recruits prior to training was 291 N in the right (lateral quadrant), 285.5 N in the left lateral quadrant and 205 N in the anterior area. After training the median of measured forces in the right quadrant was 312 N, in the left 313 N and in the anterior area 216 N Greater bite forces after training on all measured places were statistically proved. Increased activity of masticatory muscles can have the same effect on the values of bite forces as bite training. There are few data on the correlation between physical muscles and values of bite forces. The results of those studies are doubtful. In this study, after three months of conditional training, the body mass of the recruits had increased and they expressed greater values of bite forces. However, correlation between body mass and bite forces cannot be proved with certainty.  相似文献   
52.
The reproductive development of the Christmas rose (Helleborus niger L.) is characterized by an uncommon feature in the world of flowering plants: after fertilization the white perianth becomes green and photosynthetically active and persists during fruit development. In the flowers in which fertilization was prevented by emasculation (unfertilized) or entire reproductive organs were removed (depistillated), the elongation of the peduncle was reduced by 20?C30%, and vascular development, particularly lignin deposition in sclerenchyma, was arrested. Chlorophyll accumulation in sepals and their photosynthetic efficacy were up to 80% lower in comparison to fertilized flowers. Endogenous auxins were investigated in floral and fruit tissues and their potential roles in these processes are discussed. Analytical data of free indole-3-acetic acid, indole-3-ethanol (IEt), and seven amino acid conjugates were afforded by LC-MS/MS in floral tissues of fertilized as well as unfertilized and depistillated flowers. Among amino acid conjugates, novel ones with Val, Gly, and Phe were identified and quantified in the anthers, and in the fruit during development. Reproductive organs before fertilization followed by developing fruit at post-anthesis were the main source of auxin. Tissues of unfertilized and depistillated flowers accumulated significantly lower levels of auxin. Upon depistillation, auxin content in the peduncle and sepal was decreased to 4 and 45%, respectively, in comparison to fruit-bearing flowers. This study suggests that auxin arising in developing fruit may participate, in part, in the coordination of the Christmas rose peduncle elongation and its vascular development.  相似文献   
53.
In this paper we report the results of the microbiological analysis of the samples taken from the mummy from the collection of the Archaeological museum in Zagreb, Croatia. Samples were taken from specific places such as oral, orbital, abdominal cavity and bandages surrounding the mummy, and analyzed in Department of Microbiology and Hospital Infections in University Hospital "Dubrava" in Zagreb and in National Reference Laboratory for systemic mycoses of Croatian National Institute of Public Health in Zagreb. The analysis indicated that all of the found organisms were non-primary pathogenic and are not harmful for healthy humans. Isolated microorganisms mainly belonged to the group of saprophytic fungi as listed: Monilia spp., Penicillium spp., Alternaria spp., Aspergillus fumigatus, Aspergillus nidulans, Rhizopus spp. and Chrysosporium spp. and to the genus of saprophytic bacteria, Bacillus spp.  相似文献   
54.
A screening programme to detect preinvasive carcinoma of the cervix was started in British Columbia in 1949. Since 1970 the number of women who have been screened at least once has been maintained at about 85% of the population at risk. More than 500 000 cervical smears are being examined each year in the central laboratory. There has been an appreciable increase in the number of cases and rates of carcinoma in situ seen since 1970, particularly in women between 20 and 30 years of age. Since the programme started over 26 000 cases of squamous carcinoma in situ have been detected and treated. The incidence of clinically invasive squamous carcinoma of the cervix has fallen by 78% during the period under review, and mortality from squamous carcinoma of the cervix has fallen by 72%. A colposcopy programme, introduced throughout British Columbia over the past 12 years, has been important in reducing the problems of managing preinvasive lesions, particularly in younger women.It is concluded that the reduction in morbidity and mortality from invasive squamous cancer of the cervix in British Columbia over the past 30 years is directly attributable to the province wide screening programme and that a large potential increase in invasive cervical cancer rates among younger women is being prevented.  相似文献   
55.
A general procedure for manipulating protoplasts of three Streptomyces rimosus strains was developed. More than 50% regeneration efficiency was obtained by optimizing the osmotic stabilizer concentrations and modifying the plating procedure. Preparation and regeneration of protoplasts were studied by both phase-contrast and electron microscopy. After cell wall degradation with lysozyme, protoplasts about 1,000 to 1,500 nm in diameter appeared. The reversion process exhibited normal and aberrant regeneration of protoplasts to hyphae and to spherical cells, respectively. Spherical cells contained no alpha, epsilon-ll-diaminopimelic acid and were colorless or red after Gram staining. They showed consistent stability during at least five subsequent subcultivations. However, the omission of glycine from the precultivation medium reduced the unusual process of regeneration almost completely. After normal protoplast regeneration, the production of oxytetracycline by single isolates was not affected.  相似文献   
56.
While searching for true lysogens among oxytetracycline-producing Streptomyces rimosus strains, free phage particles were detected and isolated from a liquid culture of S. rimosus ATCC 10970 (R7). The actinophage, designated RP2, appears to be a typical temperate DNA phage producing turbid plaques on the sensitive strain S. rimosus R6. Electron microscopic examination of RP2 lysates showed that it belongs to group B of Bradley's morphological classification. The rate of RP2 adsoprption at 28 degrees C appeared to be low. The length of the latent period was about 6 h and the average burst size about 120 phage particles. The lysogenic nature of the host-virus system described was established on the basis of the following characteristics: spontaneous lysis frequency of 2 X 10(-6) per cell, resistance to curing with phage-specific antiserum, spontaneous curing frequency of less than 0.05% and immunity to superinfection with the homologous phage. Clear-plaque mutants of RP2, which failed to lysogenize sensitive cultures, arose at a frequency of 10(-5).  相似文献   
57.
The aim of this study was to determine level of serum IgA, IgG and IgM in patients with OLR as indicators of humoral immunity which might reflect cell-mediated immunity. This study was conducted on 30 patients (age 60.17 +/- 11.75) with clinically and histopathologically confirmed diagnosis of OLR and 30 healthy controls (age 56.16 +/- 11.82) Determination of serum IgA, IgG and IgM was performed by use of standard laser nephelometry in both patients and controls. Statistical analysis was done using Mann-Whitney U test and the level of significance was determined as p values lower than 0.05. Serum IgA and IgM in patients with OLR were significantly increased in comparison to the control group, while serum IgG levels were higher in patients with OLR but they did not reach significance. We might conclude that elevated levels of serum IgA and IgM show that humoral immunity is implicated in the pathogenesis of OLR.  相似文献   
58.
The cloning, sequencing and high-level expression of the gene encoding extracellular lipase from Streptomyces rimosus R6-554W have been recently described, and the primary structure of this gene product was deduced using a bioinformatic approach. In this study, capillary electrophoresis-on-the-chip and mass spectrometry were used to characterize native and overexpressed extracellular lipase protein from S. rimosus . The exact molecular mass of the wild-type and the overexpressed lipase, determined by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, were in excellent agreement (Deltam=0.11 Da and Deltam=0.26 Da, respectively) with a value of 24165.76 Da calculated from the structure deduced from the nucleotide sequence, considering the mature enzyme with all six cysteines forming disulfide bridges. The primary structure derived from the nucleotide sequence was completely verified using a combination of tryptic digestion and formic acid cleavage of the protein, followed by peptide mass fingerprinting. Selected peptides were further investigated by MALDI low-energy collision-induced dissociation hybrid tandem mass spectrometry, allowing the unambiguous determination of their predicted amino acid sequence. No post-translational modifications of mature S. rimosus lipase were detected. Comparison of the peptide mass fingerprints from the reduced and non-reduced overexpressed enzyme unequivocally revealed three intramolecular disulfide bonds with the following linkages: C27-C52, C93-C101 and C151-C198.  相似文献   
59.
The prayer book The Hours of the Blessed Virgin Mary, known as The Farnese Hours, was illustrated by the Croatian miniaturist, Julije Klović, between 1539 and 1546 in Rome. In this masterpiece of Renaissance miniature art, Klović drew in colour a bird of paradise. In 2001, the pictured bird was determined to be a Raggiana Bird of Paradise, Paradisaea raggiana P. L. Sclater 1873. Our later determination shows that it is actually a Greater Bird of Paradise Paradisaea apoda (Linnaeus 1758) and the first drawing of this species in colour in Europe. Klović’s model for the Greater Bird of Paradise was one of the first trade skins of birds of paradise that, from 1522, had been arriving in Europe. Revision of the early drawings of the birds of paradise species in Europe, relevant to the Klović drawing model, has also been carried out and is discussed.  相似文献   
60.
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