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41.
A 5-year-old, spayed female German Shepherd dog was admitted to hospital with marked generalised lymphadenomegaly and splenomegaly. A stage Va B-cell multicentric lymphoma was diagnosed on clinical, cytological (lymph node, bone marrow), histological-immunohistochemical (lymph node excision) and imaging grounds. Since no satisfactory remission was achieved using a multi-drug chemotherapy protocol that included cyclophosphamide, vincristine, cytosine arabinoside, prednisolone, and subsequently supplemented by L-asparaginase, it was replaced by another protocol combining vincristine, L-asparaginase, prednisolone, cyclophosphamide and doxorubicin. Soon after the third weekly session of the second protocol, the clinical status of the animal deteriorated suddenly and severely, with a bleeding tendency, jaundice, hyperuricaemia, hyperphosphataemia, azotaemia, hyperbilirubinaemia and, presumptive disseminated intravascular coagulation. There was also complete regression of lymphadenomegaly. This report emphasises the clinicopathological features and the diagnostic peculiarities of the acute tumour lysis syndrome, which occurs uncommonly in dogs.  相似文献   
42.
In order to conserve and culture the cichlid fish Archocentrus nigrofasciatus, more information about its reproductive biology and its larval behavior and morphogenesis is necessary. Currently, temperatures ranging from 21 to 27 °C are used in ornamental aquaculture hatcheries. Lower temperatures are preferred to reduce the costs of water heating, and 23 °C is usually the selected temperature. However, there is limited information on culturing protocols for ornamental species and most of the information generated on this topic remains scarce. Thus, the present study examines the morphological development of Archocentrus nigrofasciatus during the yolk‐sac period up to the age of 100 h post‐hatching in relation to 2 temperature regimes used in ornamental aquaculture: a temperature of 27 °C (thermal optimum) and a decreased temperature of 23 °C (thermal tolerance). The results of this study suggest that the 27 °C temperature generates intense morphological changes in yolk‐sac development in a shorter period. This has advantages as it reduces the time of yolk‐sac larval development, and, thus, minimizes the transition phase to exogenous feeding and maximizes the efficiency at which yolk is converted into body tissues. The present paper provides necessary information to produce freshwater ornamental fish with better practices so as to increase larval survival and capitalize on time for growth.  相似文献   
43.
Tropospheric ozone (O3) has long been documented to cause an injury to plants, but a plants’ protectant, widely applicable in agronomical practice, does not exist. We evaluated the potential antiozonate efficacy of the antitranspirant di-1-p-menthene (Vapor Gard) compared with ethylenediurea (EDU) on Bel-W3 tobacco plants. Plants were treated either with water, or by EDU (10, 100, and 500 mg dm?3), or by vapor (1, 5, 10, and 50 ml dm?3) and were exposed either to O3-enriched (90 ppb) or O3-free air, for 12 days and 8 h day?1. EDU when applied at 10 mg dm?3 did not protect the plants against O3, but when applied at 100 and 500 mg dm?3 offered a significant protection to the plants. Vapor, when applied at 1 ml dm?3 did not protect the plants against O3, neither by terms of foliar visible injury nor by terms of aboveground biomass. In addition, when applied at 10 and 50 ml dm?3 caused phytotoxicity to all the plants, which it was expressed as necrotic spots on the leaves’ surface, misshaping of the leaves, or short plants' height. It is obvious that vapor does not protect Bel-W3 tobacco plants against O3. The antiozonate role of di-1-p-menthene is species-specific and probably occurs only under short-term exposures.  相似文献   
44.
Interaction of regulatory DNA binding proteins with their target sites is usually preceded by binding to nonspecific DNA. This speeds up the search for the target site by several orders of magnitude. We report the solution structure and dynamics of the complex of a dimeric lac repressor DNA binding domain with nonspecific DNA. The same set of residues can switch roles from a purely electrostatic interaction with the DNA backbone in the nonspecific complex to a highly specific binding mode with the base pairs of the cognate operator sequence. The protein-DNA interface of the nonspecific complex is flexible on biologically relevant time scales that may assist in the rapid and efficient finding of the target site.  相似文献   
45.
The presence of organotin (OT) compounds was investigated in coastal areas (10 stations), wastewater treatment systems (six stations), rivers (19 stations) and lakes (12 stations) throughout Greece, in three sampling campaigns organized between October 1998 and September 1999. A screening method for the determination of toluene extractable organotins (TEOTs) by Electrothermal Atomic Absorption Spectrometry (ETAAS) was used during the first two sampling campaigns. TEOTs (sum of tributyltin, TBT, dibutyltin, DBT and triphenyltin, TPhT) were detected in most seawater and wastewater samples at concentrations up to 19.4 and 89.9 ng l?1, respectively, while they were detected occasionally in surface water. During the third sampling campaign, OT compounds were extracted in selected stations using direct derivatization with NaBEt4 in acidic medium and analysed by Gas Chromatography–Mass Spectrometry (GC–MS). In seawater, the levels of TBT, DBT and monobutyltin (MBT) were varied between < 2 and 70, 159 and 19 ng l?1, respectively and tend to decrease with increasing distance from the coastline. TPhT was not detected in any of the samples. Significant concentrations of OT species were detected in influent wastewater, up to 384, 76.2 and 67.8 ng l?1 for TBT, DBT and MBT, respectively. OTs were mainly associated with the suspended solids and were totally removed during wastewater treatment.  相似文献   
46.
This study was designed to evaluate the metabolic response to Corinthian raisins in healthy and in patients with type 2 diabetes mellitus. Healthy subjects (n?=?15) and diabetic patients (n?=?15) received 74 g raisins or 50 g glucose as reference food. Blood samples were collected at time 0 (before the consumption) and 30, 60, 90, 120, 150 and 180 min after raisin or glucose consumption. There was no significant difference in baseline glucose and insulin between raisins and reference in both groups. The difference at glucose peaks between raisins and reference was significant in healthy and in diabetics. Glycemic and insulinemic responses were decreased after raisin consumption compared to reference. An estimate of the glycemic index would be 66.3?±?3.4.  相似文献   
47.
The objective of the study was to determine the immunohistochemical expression of canine TERT in canine testicular tumours comparing two different antibodies for TERT, and to correlate them with well established markers specific to dividing cells such as PCNA and ki67, and with expression of the p53 tumour suppressor gene. The study included 36 cases of canine testicular tumours, which were categorized as 12 Sertoli Cell Tumours (SCT), 20 seminomas, 3 interstitial cell tumours and 1 mixed germ cell-sex cord stromal tumour (MT). Two antibodies for hTERT were examined; a highly specific TERT antibody, RCK-hTERT, was evaluated for the first time. Immunodetection of RCK-hTERT was observed in 31% of tumours examined (6/20 Seminomas, 4/12 SCT, 1/3 interstitial cell tumour and 0/1 mixed germ cell-sex cord stromal tumour), while the NCL-hTERT in 67% of them (15/20 Seminomas, 6/12 SCT, 3/3 interstitial cell tumour and 0/1 ΜΤ). PCNA immunoreactivity was detected in all cases. Regarding ki67, 3 SCT, 12 seminomas and all interstitial cell tumours showed clear immunoreaction. p53 immunoreactivity was detected in 6 SCT, 15 seminomas and all interstitial cell tumours. The immunohistochemical expression of both TERT antibodies are discussed and compared in order to clarify their potential usefulness in canine testicular malignancies in relation to the expression of well known cell cycle markers. Our results indicate that TERT and PCNA are useful proliferation markers but not helpful to evaluate prognosis. Instead of that ki67 and p53 could be used for predicting aggressiveness in this group of tumours  相似文献   
48.
49.
The aim of the present paper is to investigate the influence of biotic factors (fungi and insects) on the mechanical properties of wood through the effect of blue-stain, taking into account the time of harvesting and the time of stay of wood in the forest. Specifically, the resistance to axial compression and to bending (modulus of rupture (MOR)) was studied using infected specimens of Scots Pine (Pinus sylvestris) and Norway Spruce (Picea abies) (the usual types of wood used in woodwork). The specimens were obtained from logs of Scots Pine and Norway Spruce that were harvested in three different seasons of year, namely in July 2012, November 2012 and June 2013, respectively, in the forest of Elatia-Greece, and the attack pace by biotic factors with respect to the time of logging was studied. The placement of the experimental surfaces of each type of tree was made on skid road and in the stand. Totally, 120 laboratory measurements in axial compression and 120 measurements in bending (MOR) took place. The results proved that blue-stain hardly affect the mechanical properties of both wooden species and particularly the specimens that were derived during the winter logging.  相似文献   
50.
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