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Introduction:  We evaluated the totally implantable subcutaneous vascular access port (VAP) in 16 cancer patients undergoing intermittent chemotherapy for more than 30 months.
Methods:  Ports were surgically placed (The CompanionPort, Norfolk Vet Products, Skokie, Illinois 60076) in the jugular vein of 12 dogs and 4 cats between 1/2002 and 7/2004. Body weight determined polyurethane catheter size (4, 5, 7 fr.). The polysulfone port, surrounded by titanium, was anchored to subcutaneous tissue in the dorsolateral neck and confirmed with C‐arm fluoroscopy. All blood samples were obtained via VAP. Nine anticancer agents, other medications, crystalloids/colloids, and whole blood were administered. Ports were flushed every 4–5 weeks with heparinized saline solution (100 IU/ml). Removed catheters were submitted for bacteriology.
Results:  Seven of 16 animals are still alive. VAP were used for 1.5 to more than 30 months with 4–60 injections/port. Catheter tips were visualized from the left atrium distally into the caudal vena cava. Adverse events included post‐operative subcutaneous bruising and/or hematoma (4/16), difficult aspiration (4/16), catheter malposition (1/16), positional flushing (1/16), and occlusion requiring replacement (1/16). No thrombus formation or extravasation was evident. Bacterial colonization without signs of septicemia was observed in 3/4 catheters.
Conclusions:  VAP are an effective way of achieving long‐term venous access in the dog and cat. Complications are typically minor and infrequent.  相似文献   
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The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.  相似文献   
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Changes in prevalence in intramammary infection, by pathogen type, in herds applying a stringent contagious mastitis control programme was studied. Enrollment of 1651 lactating cows and collection of milk samples was made in this ancillary study to a cohort study of the dynamics of mastitis prevalence after adoption of a strict contagious mastitis control programme that targeted the elimination of mastitis caused by Staphylococcus aureus. Nine commercial dairies in Italy were used. Aseptic collection of milk samples from all lactating cows was performed at the time of enrollment, from all cows within 7–14 days of entering the lactating herd after the date of enrollment, and from all lactating cows at 2, 4, 7, 10 and 14 months after the date of enrollment. Prevalence of intramammary infection by pathogen type was determined from culture of milk samples. Application of the strict contagious mastitis programme did not lead to an increased risk of non‐contagious mastitis. The risk of coliform, environmental streptococcal and coagulase‐negative staphylococcal intramammary infections decreased after adoption of the programme. The data reported herein indicate that the overall risk for any intramammary infections decreases with adoption of a strict contagious mastitis programme, and that such a programme therefore does not necessarily lead to an increase in environmental mastitis.  相似文献   
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