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91.
It has been suggested that management system, milk yield, parity, body condition score and ambient temperature can significantly influence the rate of early pregnancy loss in dairy cattle. The objectives of this study were to establish the extent and patterns of early pregnancy loss from days 32 to 86 of gestation, and to check relationships between management system, milk yield, ambient temperature (quartile), body condition score, bull and parity on the early pregnancy loss rate for Simmental dairy cattle in Croatia. Animals were housed in two dairy farms with two different management systems (pasture based-group A, n=435 and intensive-group B, n=425) with a total of 151 heifers and 709 cows. Overall pregnancy losses were recorded in 67 (7.79%) animals, with late embryonic losses in 30 (44.77%) and early fetal losses in 37 (55.23%) animals (P>0.05). Early pregnancy losses were twofold higher in group B when compared to the group A (P<0.05). More than the half of pregnancy losses were recorded during the III quartile (P<0.05). There was no significant relationship between the paternal bull and pregnancy loss rate. Low body condition score (BCS 2-3) was associated with the highest, while BCS 3.25-4 showed the lowest pregnancy loss rate (P<0.05). The pregnancy loss rate increased in parallel with parity and milk yield increase. 相似文献
92.
Gall V Kosec V Vranes HS Jukić M Filipović-Djaković I Vuković A 《Collegium antropologicum》2011,35(3):715-718
The aim of this study was to determine physiological value of platelet serotonin (5-HT) and its variations in the group of women in term pregnancy and after birth. Obtained results were compared to the platelet 5-HT level in nonpregnant women group. Determination of normal level of 5-HT in pregnancy and after could help in its further measurement and evaluation of different psychologic and psychiatric disorders related to pregnant and postpartal period, including better understanding of mood changes after the birth. A total of 137 healthy Croatian women were enrolled in the study--82 of them were pregnant and 55 were not. Their blood was sampled and the platelet serotonin concentration was determined. In pregnant women the blood was sampled twice: at term pregnancy, and soon after birth. The mean value of 5-HT in pregnant women was 1.209 nmol/mg protein, after the delivery 1.045 nmol/mg protein, and in non pregnant 1.088 nmol/ mg protein. The concentrations were significantly different in those three groups. We did not find differences in 5-HT levels in groups divided by age. 相似文献
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95.
The last step in ribosome-catalyzed protein synthesis is the hydrolytic release of the newly formed polypeptide from the P-site bound tRNA. Hydrolysis of the ester link of the peptidyl-tRNA is stimulated normally by the binding of release factors (RFs). However, an unacylated tRNA or just CCA binding to the ribosomal A site can also stimulate deacylation under some nonphysiological conditions. Although the sequence of events is well described by biochemical studies, the structural basis of the mechanism underlying this process is not well understood. Two new structures of the large ribosomal subunit of Haloarcula marismortui complexed with a peptidyl-tRNA analog in the P site and two oligonucleotide mimics of unacylated tRNA, CCA and CA, in the A site show that the binding of either CA or CCA induces a very similar conformational change in the peptidyl-transferase center as induced by aminoacyl-CCA. However, only CCA positions a water molecule appropriately to attack the carbonyl carbon of the peptidyl-tRNA and stabilizes the proper orientation of the ester link for hydrolysis. We, thus, conclude that both the ability of the O3′-hydroxyl group of the A-site A76 to position the water and the A-site CCA induced conformational change of the PTC are critical for the catalysis of the deacylation of the peptidyl-tRNA by CCA, and perhaps, an analogous mechanism is used by RFs. 相似文献
96.
Primož Treven Kristyna Turkova Aljoša Trmčić Tanja Obermajer Irena Rogelj Bojana Bogovič Matijašić 《Folia microbiologica》2013,58(6):623-630
Lactobacillus gasseri K7 is a probiotic strain that produces bacteriocins gassericin K7 A and K7 B. In order to develop a real-time quantitative PCR assay for the detection of L. gasseri K7, 18 reference strains of the Lactobacillus acidophilus group and 45 faecal samples of adults who have never consumed strain K7 were tested with PCR using 14 pairs of primers specific for gassericin K7 A and K7 B gene determinants. Incomplete gassericin K7 A or K7 B gene clusters were found to be dispersed in different lactobacilli strains as well as in faecal microbiota. One pair of primers was found to be specific for the total gene cluster of gassericin K7A and one for gassericin K7B. The real-time PCR analysis of faecal samples spiked with K7 strain revealed that primers specific for the gene cluster of the gassericin K7 A were more suitable for quantitative determination than those for gassericin K7 B, due to the lower detection level. Targeting of the gassericin K7 A or K7 B gene cluster with specific primers could be used for detection and quantification of L. gasseri K7 in human faecal samples without prior cultivation. The results of this study also present new insights into the prevalence of bacteriocin-encoding genes in gastrointestinal tract. 相似文献
97.
Zinić B Krizmanić I Glavas-Obrovac Lj Karner I Zinić M 《Nucleosides, nucleotides & nucleic acids》2003,22(5-8):1623-1625
The introduction of sulfonamido group on the C-2 position of pyrimidine nucleosides was achieved by ring opening of 2,2'- and 2,3'-anhydronucleosides. N-sulfonyl derivatives of nucleobases and sulfonamido derivatives of nucleosides were assayed for in vitro antitumor activity. 相似文献
98.
The relationship between the bone mineral density (BMD) in Croatian female adults and the average incoming solar radiation at the ground was investigated. The study included 387 volunteers of average age of 60 years from three different towns: Pula (n = 128, age from 35 to 76), Krapina (n = 141, age from 43 to 77), and Zagreb (n = 118, age from 32 to 79). Apart from the different lifestyle, each of above towns is characterized by different incoming solar radiation, where values of 503.3 kJ cm-2, 471.2 kJ cm-2 and 436.3 kJ cm-2 correspond to average annual radiation at the ground for Pula, Krapina and Zagreb, respectively. Heel BMD was measured by clinical bone sonometer (Sahara). On the average the BMD was highest for Pula (0.469 g cm-2) and the lowest for Zagreb (0.433 g cm-2). Similarly, the percentage of normal bones was the highest for Pula (46.1%) and the lowest for Zagreb (32.2%). Osteopenic bones were the most frequent for Zagreb (61.0%), while corresponding figures for Pula and Krapina were 46.9% and 43.6%, respectively. Osteoporosis varied from 6.8% in Zagreb to 11.4% in Krapina. A test of independence by contingency table confirmed at the significance level alpha = 0.05 that probability of normal bone occurrence increases with the increase of incoming solar radiation. Results of the multiple regression analysis suggest the dependence of BMD on woman's age and weight, and incoming solar radiation at the place of habitation. 相似文献
99.
The aim of this study was to investigate both the efficacy and safety of sedation with propofol during urgent therapeutic gastroscopy in patients with upper gastrointestinal bleeding. This prospective study included a total of 110 patients. Propofol was administered intravenously at the starting dose of 1 mg/kg body weight and was followed by repeated doses. Oxygen saturation and heart rate were monitored by pulse oxymetry. The mean dose of propofol administered was 161 +/- 49 mg. Urgent upper GI endoscopy under propofol sedation was successful in 98% of cases. Endoscopists rated the sedation as good in 83.6%, satisfactory in 14.5%, and poor in 1.8% of patients. Potentially harmful drop in oxygen saturation below 85% was observed in 5.5% of patients, whereas a temporary drop in heart rate below 50 beats/min was observed in 11.8%, not requiring any intervention. Almost 93% of patients could not remember the beginning or the end of the intervention. This data demonstrates that sedation with propofol is suitable for use in patients with upper gastrointestinal bleeding undergoing urgent endoscopy. 相似文献
100.
Milosević D Batinić D Tesović G Konjevoda P Kniewald H Subat-Dezulović M Grković L Topalović-Grković M Turudić D Spajić B 《Collegium antropologicum》2010,34(3):893-897
The pathogenesis of recurrent urinary tract infections (UTIs) in preschool children with anatomically correct urinary tract (UT) is rather obscure. In girls, the bladder wall changes of cystitis cystica (CC) may be per se responsible for UTIs recurrence. During the 20-year period, 127 preschool children (125 girls; median age: 6.1 years) with CC, in whom UT anomalies were excluded, were diagnosed. The mean duration of UTIs symptoms prior to diagnosis was 3.31 +/- 2.51 years. Cystoscopical findings were labelled as mild, moderate and severe in 22.8%, 39.4% and 37.8% of patients, respectively. Following the confirmation of CC, long-term chemoprophylaxis with sulfamethoxazole-trimethoprim/nitrofurantoin was administered. A one year UTI-free period after chemoprophylaxis discontinuation was defined as therapeutic success. With 2.5 years median duration of regular chemoprophylaxis this goal was achieved in 58 children mainly with mild/ moderate CC. Thirty children from "improved/unchanged" group taking regular prophylaxis had significant reduction of UTIs ("improved"). Only 12 children belonging to the same group taking regular prophylaxis and all children with irregular prophylaxis had approximately the same number of UTIs as before treatment ("unchanged"). The "improved/unchanged" outcomes were predominantly found in children with severe form of CC. Although urodynamic disturbances detected in more than 50% of patients in whom urodynamics was performed were not found influential on the disease outcome, they could be responsible for its development. The results of our study suggest that regular and long-lasting chemoprophylaxis remains a basis for successful treatment for majority of patients with CC, even those with severe forms. If not treated properly with chemoprophylactic agents and without fair compliance in taking drugs, the disease is prone to recurrent UTIs. 相似文献