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81.
The purpose of this study was to (1) establish a technique for ultrasound-guided trans-splenic portal scintigraphy (TSPS) using 99mTcO4(-), (2) evaluate portal vein morphology, (3) compare the radiation exposures for TSPS vs. per-rectal portal scintigraphy (PRPS), and (4) compare the quality of numerical data from the TSPS vs. PRPS. Eight juvenile dogs underwent PRPS and TSPS (minimum of 48h between studies) after initial screening tests. PRPS was done according to established protocol using 425 +/- 36MBq (mean +/- SD) of 99mTcO4(-). TSPS was done with the dogs in right lateral recumbency over the gamma camera. 99mTcO4(-) (57 +/- 13.9 MBq) was injected into the spleen 1-2s following initiation of the dynamic acquisition. The frame rate was 4 frames/s for 5 min. There was significantly lower radioactivity of 99mTcO4(-) given and significantly higher total counts recorded in the liver and heart during the TSPS compared with PRPS. The total counts for the TSPS and PRPS were 7120 +/- 4386 and 830 +/- 523, respectively. Percent absorption from the spleen was 52.5 +/- 19.1% compared with 9.2 +/- 5.7% for the colon. Calculated transit time for the TSPS studies was 7 +/- 2.3s. In TSPS studies, the splenic and portal veins were clearly identified. Radiation exposure levels of the dogs were significantly lower following TSPS than after PRPS. TSPS appears superior to PRPS as a method to image the portal venous system representing a valid alternative diagnostic test for animals with suspected portosystemic shunts.  相似文献   
82.
Owners and trainers exercise sporting dogs to increase their fitness and optimize their conditioning and performance. Training is designed to in-crease strength, endurance, and agility and is sport-specific. Sporting dogs are susceptible to specific musculoskeletal injuries. The rehabilitation of sporting dogs after these injuries follows specific principles during the acute, subacute, and reconditioning periods.  相似文献   
83.
OBJECTIVE: To quantify angular excursions; net joint moments; and powers across the stifle, tarsal, and metatarsophalangeal (MTP) joints in Labrador Retrievers and Greyhounds and investigate differences in joint mechanics between these 2 breeds of dogs. ANIMALS: 12 clinically normal dogs (6 Greyhounds and 6 Labrador Retrievers) with no history of hind limb lameness. PROCEDURE: Small retroreflective markers were applied to the skin over the pelvic limb joints, and a 4-camera kinematic system captured data at 200 Hz in tandem with force platform data while the dogs trotted on a runway. Breed-specific morphometric data were combined with kinematic and force data in an inverse-dynamics solution for stance-phase net joint moments and powers at the stifle, tarsal, and MTP joints. RESULTS: There were gross differences in kinematic patterns between Greyhounds and Labradors. At the stifle and tarsal joints, moment and power patterns were similar in shape, but amplitudes were larger for the Greyhounds. The MTP joint was a net absorber of energy, and this was greater in the Greyhounds. Greyhounds had a positive phase across the stifle, tarsal, and MTP joints at the end of stance for an active push-off, whereas for the Labrador Retrievers, the only positive phase was across the tarsus, and this was small, compared with values for the Greyhounds. CONCLUSIONS AND CLINICAL RELEVANCE: Gross differences in pelvic limb mechanics are evident between Greyhounds and Labrador Retrievers. Joint kinetics in specific dogs should be compared against breed-specific patterns.  相似文献   
84.
OBJECTIVE: To describe clinical findings, surgical treatment, and outcome associated with trichophytobezoar duodenal obstruction in New World camelids. STUDY DESIGN: Retrospective study. ANIMALS: Alpacas (7) and 1 llama. METHODS: Historical and clinical data were obtained from the medical records of New World camelids with a diagnosis of trichophytobezoar duodenal obstruction confirmed by surgical exploration or necropsy. RESULTS: Seven camelids were <1 year old. Abnormal clinical findings included anorexia, reduced fecal output, recumbency, colic, abdominal distension, regurgitation, decreased serum chloride concentration, increased serum bicarbonate concentration, and/or elevated first gastric compartment chloride concentration. Survey abdominal radiographs obtained (4 animals) revealed gastric distension (4) and/or visualization of the obstruction (2). Diagnosis was confirmed at necropsy (1) or surgery (7). Right paracostal celiotomy was performed on all animals and duodenotomy (3) or retropulsion of the trichophytobezoar combined with third compartment gastrotomy (4) was used to remove the obstruction. Six animals survived to discharge and 5 were healthy at follow-up, 8-20 months later. The remaining discharged alpaca was healthy at 12 months but subsequently died of unrelated causes. CONCLUSIONS: Diagnosis of trichophytobezoar duodenal obstruction should be considered in juvenile New World camelids with abdominal distension and hypochloremic metabolic alkalosis. Right paracostal celiotomy can be used for access to the descending duodenum and third gastric compartment for surgical relief of obstruction. CLINICAL RELEVANCE: Duodenal obstruction from bezoars should be considered in New World camelids <1year of age with abdominal distension and hypochloremic metabolic alkalosis. Surgical relief of the obstruction by right paracostal celiotomy has a good prognosis.  相似文献   
85.

Background

Chronic exposure to cadmium (Cd), even at low concentrations, has an adverse impact on the skeletal system. Histologically, primary and secondary osteons as basic structural elements of compact bone can also be affected by several toxicants leading to changes in bone vascularization and mechanical properties of the bone. The current study was designed to investigate the effect of subchronic peroral exposure to Cd on femoral bone structure including histomorphometry of the osteons in adult male rats.In our study, 20 one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males received a drinking water containing 30 mg of CdCl2/L, for 90 days. Ten one-month-old males without Cd intoxication served as a control group. After 90 days of daily peroral exposure, body weight, femoral weight, femoral length, cortical bone thickness and histological structure of the femora were analysed.

Results

We found that subchronic peroral application of Cd had no significant effect on body weight, femoral length and cortical bone thickness in adult rats. On the other hand, femoral weight was significantly increased (P < 0.05) in Cd-intoxicated rats. These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta and supplied primary and secondary osteons. Additionally, a few resorption lacunae which are connected with an early stage of osteoporosis were identified in these individuals. Histomorphometrical evaluations showed that all variables (area, perimeter, maximum and minimum diameter) of the primary osteons’ vascular canals, Haversian canals and secondary osteons were significantly decreased (P < 0.05) in the Cd group rats. This fact points to alterations in bone vascularization.

Conclusions

Subchronic peroral exposure to Cd significantly influences femoral weight and histological structure of compact bone in adult male rats. It induces an early stage of osteoporosis and causes reduced bone vascularization. Histomorphometrical changes of primary and secondary osteons allow for the conclusion that the bone mechanical properties could be weakened in the Cd group rats. The current study significantly expands the knowledge on damaging action of Cd on the bone.  相似文献   
86.
87.
Salmonella Kentucky is among the most frequently isolated S. enterica serovars from food animals in the United States. Recent research on isolates recovered from these animals suggests there may be geographic and host specificity signatures associated with S. Kentucky strains. However, the sources and genomic features of human clinical S. Kentucky isolated in the United States remain poorly described. To investigate the characteristics of clinical S. Kentucky and the possible sources of these infections, the genomes of all S. Kentucky isolates recovered from human clinical cases in the State of Maryland between 2011 and 2015 (n = 12) were sequenced and compared to a database of 525 previously sequenced S. Kentucky genomes representing 12 sequence types (ST) collected from multiple sources on several continents. Of the 12 human clinical S. Kentucky isolates from Maryland, nine were ST198, two were ST152, and one was ST314. Forty‐one per cent of isolates were recovered from patients reporting recent international travel and 58% of isolates encoded genomic characteristics similar to those originating outside of the United States. Of the five isolates not associated with international travel, three encoded antibiotic resistance genes conferring resistance to tetracycline or aminoglycosides, while two others only encoded the cryptic aac(6′)‐Iaa gene. Five isolates recovered from individuals with international travel histories (ST198) and two for which travel was not recorded (ST198) encoded genes conferring resistance to between 4 and 7 classes of antibiotics. Seven ST198 genomes encoded the Salmonella Genomic Island 1 and substitutions in the gyrA and parC genes known to confer resistance to ciprofloxacin. Case report data on food consumption and travel were, for the most part, consistent with the inferred S. Kentucky phylogeny. Results of this study indicate that the majority of S. Kentucky infections in Maryland are caused by ST198 which may originate outside of North America.  相似文献   
88.
Plastination is a late 20th century preservation methodology which replaces tissue fluid within a specimen with a curable polymer, such as silicone. Plastination yields superb, beautiful, well‐preserved specimens each with their own unique qualities. Silicone polymer is used around the world to preserve macroscopic cadavers or portions/organs thereof. Plastination was conceived by Dr. Gunther von Hagens, Universität Heidelberg, Heidelberg, Germany prior to 1977. Silicone polymer was the primary polymer which emerged initially for plastination. The Biodur® line of silicone polymer and additives was chosen and manufactured because it has consistently produced the best plastinates since the inception of plastination. Since the discovery of silicone, generic and similar silicone polymers are known and used around the World by many industries and used in numerous products. The plastination process has four steps: Specimen preparation, Specimen dehydration and degreasing, Vacuum‐forced impregnation of specimens and Specimen hardening.  相似文献   
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