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31.
During routine monitoring of yellow-crowned parakeets in the Poulter Valley of the South Island of New Zealand, a dead parakeet chick was discovered in a nest. Known parrot-infecting viruses, such as beak and feather disease virus (BFDV), avian polyomavirus (APV), and parrot hepatitis B virus (PHBV), were not detected in the nesting material. However, we recovered two novel single-stranded DNA viruses (ssDNA), CynNCXV (2308 nt) and CynNCKV (2087 nt), which have genome architectures similar to those of circoviruses, characterised by circular genomes with two large bidirectional open reading frames (ORFs). Both contain a stem-loop element with a conserved nonanucleotide motif, known to be required for rolling-circle replication. The full genomes had no BLASTn similarity to known ssDNA viruses. However, in both genomes the larger ORFs have BLAST similarity to known replication-associated proteins (Reps). CynNCKV has 30 % similarity to picobiliphyte nano-like virus (Picobiliphyte M5584-5) with 66-88 % coverage (e-value of 5×10?33), whereas CynNCXV has 33 % similarity to rodent stool-associated virus (RodSCV M-45) with 92-94 % coverage (e-value of 5 × 10?31). Found within these ORFs were the rolling-circle replication motifs I, II, III and the helicase motifs Walker A and Walker B. Maximum-likelihood phylogenetic analysis of the Reps reveals that these are two novel ssDNA viruses. At this point, we are unable to attribute the death of the parakeet to these two new novel ssDNA viruses.  相似文献   
32.
Dural metastasis from medullary thyroid carcinoma (MTC) is not well established in English literature. We present the case report of MTC with unusual clinical presentation as a dural-based mass in a 39-year-old male with no family history of multiple endocrine neoplasia syndrome. Magnetic resonance imaging showed an extra-axial dural-based mass in right frontal lobe with calvarium and soft tissue extension to the right superior orbit. Histopathology showed MTC with variegated morphology and various patterns. Thyroid mass and widespread metastases from medullary thyroid carcinoma were subsequently identified.  相似文献   
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Scar ectopic pregnancy is the rarest form of ectopic pregnancy and has been increasingly diagnosed all over the world. This is a life-threatening form of abnormal implantation of embryo within the myometrium and fibrous tissues in a previous scar on the uterus, especially following caesarean section. With the increasing rate of caesarean section, there is a substantial increase in this condition with better understanding of this disease. The early and accurate diagnosis with timely management can prevent pregnancy complications such as haemorrhage, uterine rupture and can preserve fertility.  相似文献   
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Purpose of the Study:

It is difficult to achieve a reliable bond between the titanium and veneering porcelain. The aim of this study was to evaluate the bond strength between titanium ceramic crowns.

Materials and Methods:

The surfaces of titanium copings were divided in two groups. Group A sandblasted with 250 um (n = 10) and Group B without sandblasting (n = 10). Low-fusing porcelain was bonded over copings. A universal testing machine was used to determine the fracture load (N) of the crowns. All data were compared using Student''s t-test.

Results:

There was a significant difference in fracture toughness between two groups (P = 0.05). The mean value of fracture strength for Group A was 721.66 N and for Group B was 396.39 N.

Conclusions:

Sandblasting improves the bond strength between titanium, and ceramic, mechanical bonding plays a crucial role in the bonding between titanium and ceramic.Key Words: Bonding, fracture load, sandblasting, titanium  相似文献   
38.
INTRODUCTIONHypoglycaemia constitutes a significant barrier to achieving glycaemic control with insulin in both Type 1 (T1DM) and Type 2 diabetes mellitus (T2DM). The International Operations Hypoglycaemia Assessment Tool (IO HAT) study was designed to determine the incidence of hypoglycaemia in insulin-treated patients with T1DM and T2DM.METHODSThe IO HAT study retrospectively and prospectively assessed the incidence of hypoglycaemia in patients with insulin-treated diabetes mellitus in nine countries. This sub-analysis included patients from Singapore with T1DM or T2DM who were aged ≥ 21 years and had completed two self-assessment questionnaires (SAQ1 and SAQ2).RESULTSOf the 50 T1DM and 320 T2DM patients who completed the SAQ1, 39 T1DM and 265 T2DM patients completed SAQ2; 100% and 90.9%, respectively, experienced at least one hypoglycaemic event prospectively. The incidence rates of any hypoglycaemia were 49.5 events per patient-year (EPPY) and 16.1 EPPY for T1DM and T2DM patients, respectively, in the four-week prospective period. Hypoglycaemia rate did not differ in terms of glycated haemoglobin level. The vast majority of T1DM or T2DM patients (92.0% and 90.7%, respectively) knew the overall definition of hypoglycaemia before study participation, although over half of the patients (T1DM 54.0%, T2DM 51.9%) defined hypoglycaemia based only on symptoms.CONCLUSIONHigh proportions of insulin-treated patients with diabetes mellitus in Singapore reported hypoglycaemic events prospectively, showing that they had underreported hypoglycaemic episodes retrospectively. Patient education can help in improving hypoglycaemia awareness and its management in the region.  相似文献   
39.
Widespread emergence of multidrug resistant (MDR) bacterial pathogens is a problem of global dimension. MDR infections are difficult to treat and frequently associated with high mortality. More than one antibiotic is commonly used to treat such infections, but scientific evidence does not favor use of combination therapy in most cases. However, there are certain subgroups where combination therapy may be beneficial, e.g. sepsis due to carbapenem-resistant Enterobacteriaceae (CRE), bacteremic pneumococcal pneumonia, and patients with multiple organ failure. Well-designed prospective studies are needed to clearly define the role of combination therapy in these subgroups.  相似文献   
40.
Correctly folded virus-like particles (VLPs) of papillomavirus (PV) display conformationally dependent epitopes that are type specific, maintained on authentic virions, and induce neutralizing antibodies. Alignment of the L1 amino acid (aa) sequences of 84 PVs revealed that the lengths of their N-termini are diverse and that multiple, possible initiation methionine (met) codons exist. The L1 gene of MusPV (MmuPV1), that naturally infects immunodeficient laboratory mouse strain (NMRI-Foxn1nu/Foxn1nu), has four met codons at the 1st, 2nd, 28th, and 30th aas from its N-terminus. Of these, the 3rd and 4th mets, that are at the 28th and 30th aa position from the N-termius, respectively, are located at the position where most PVs have their first met. These two mets, located at the 9th and 11th from the YLPP conserved aas of most PVs, should be considered as consensus initiation codons of PV L1s. Three L1 proteins of MusPV, starting from the 2nd, 3rd, and 4th mets, were expressed using a baculovirus expression system and characterized for their ability to self-assemble into VLPs. While MusPV L1 proteins starting from the 2nd met expressed an L1 protein that did not fold into VLPs, the L1s starting from the 3rd and 4th mets generated correct VLPs in abundant quantities. We now conclude that the highest quantity and best quality VLPs are made from the consensus L1 met of MusPV.  相似文献   
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