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81.
Babesiosis is a tick-borne illness endemic to the coastal areas of southern New England. Despite the enormous safety measures that transfusion and blood bank services perform for each product, transfusion of blood products is not without risk. The majority of transfusion-related reactions and complications are recognized soon after transfusion. We report a case of transfusion-acquired babesiosis in Washington State that presented 4 weeks after transfusion of a blood product from a donor living in a babesiosis-endemic area. 相似文献
82.
We describe a case of multifocal polypoid endometriosis presenting with advanced bulky disease at a variety of pelvic sites. The extent of tumor and clinical features such as vaginal bleeding and pulmonary embolus were suggestive of a malignant process. Histopathology demonstrated glands that were neither crowded nor complex, with intervening fibromatous stroma that contained occasional endometrial stromal cells. These features were consistent with the newly described condition of polypoid endometriosis. Despite the endometrioid appearance of this tumor, there was florid ciliary cell change. An association has been suggested between polypoid endometriosis and prior tamoxifen use, although this patient had no history of prior hormone use. 相似文献
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We have examined the role of the NKCC1 sodium-potassium-chloride-cotransporter in the generation of touch-evoked pain. The pain behavior of NKCC1 knockout mice (KO) was studied and compared to that of heterozygous (HE) and wild-type (WT) littermates. NKCC1 KO mice showed an increase in tail flick latencies and a reduction of the duration of pain behavior induced by intradermal capsaicin compared to HE and WT mice. All three groups of animals expressed a normal level of plasma extravasation following capsaicin applications. NKCC1 KO mice showed a reduction in stroking hyperalgesia (touch-evoked pain) compared to WT and HE mice but no differences were detected between the three groups in the expression of punctate hyperalgesia. As the NKCC1 co-transporter is responsible for the generation of presynaptic inhibition between afferent terminals in the spinal cord, these results support the notion that presynaptic interactions between low and high threshold afferents can underlie touch-evoked pain. 相似文献
85.
PURPOSE: Polyethylenimine (PEI) is a highly effective gene delivery vector, but because it is an off-the shelf material, its properties may not be optimal. To investigate the effects of the protonation properties of the polymer, we generated PEI derivatives by acetylating varying fractions of the primary and secondary amines to form secondary and tertiary amides, respectively. METHODS: Reaction of PEI with increasing amounts of acetic anhydride at 60 degrees C for 4.5 h yielded polymers with 15%, 27%, and 43% of the primary amines modified with acetyl groups. Polymer-DNA complexes were characterized by dynamic light scattering and zeta potential measurements. Cytotoxicity of the polymers was assessed by XTT assay for metabolic activity, and gene delivery efficiency was determined as the relative expression of a luciferase gene in MDA-MB-231 and C2C12 cell lines. RESULTS: Acetylation of PEI decreased the "physiological buffering capacity," defined as the moles of protons absorbed per mole of nitrogen on titration from pH 7.5 to 4.5, from 0.29 mol H+/mol N to 0.17 mol H+/mot N, 0.12 mol H+/mol N, and 0.090 mol H+/mol N for PEI-Ac15, PEI-Ac27, and PEI-Ac43, respectively. In addition, acetylation decreased the zeta potential of polyplexes from 14 mV to 8-11 mV and increased the polyplex diameter by two- to threefold. Surprisingly, acetylation had a negligible effect on cytotoxicity of the polymers and increased gene delivery effectiveness by up to 21-fold compared to unmodified PEI, both in the presence and absence of serum. CONCLUSIONS: Reduction of the buffering capacity of PEI greatly enhanced the gene delivery activity of the polymer. The mechanism is not yet understood, but the enhancement may be caused by more effective polyplex unpackaging, altered endocytic trafficking, and/or increased lipophilicity of acetylated PEI-DNA complexes. Future studies will address these possibilities in more detail. 相似文献
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Cytogenetics and molecular cytogenetics 总被引:2,自引:0,他引:2
Jackson L 《Clinical obstetrics and gynecology》2002,45(3):622-39; discussion 730-2
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89.
Love OP Shutt LJ Silfies JS Bortolotti GR Smits JE Bird DM 《Ecotoxicology (London, England)》2003,12(1-4):199-208
We experimentally examined the effects of dietary exposure to polychlorinated biphenyls (PCBs) on adrenocortical function in American kestrels (Falco sparverius). Nine captive male American kestrels previously exposed to a PCB mixture (Aroclor1248:1254:1260; 1:1:1) in their diet were subjected to a standardized capture, handling and restraint protocol designed to produce an increase in circulating corticosterone. A similar protocol has been applied to a wide range of avian species and was used here to evaluate the response of PCB-exposed and control kestrels to a defined physical stressor. Both baseline and stress-induced corticosterone levels were significantly lower in PCB-exposed birds when compared with control birds of the same age. PCB-exposed birds exhibited significantly lower corticosterone levels during the corticosterone response when compared with control birds, independent of body condition. Furthermore, baseline corticosterone concentrations exhibited a hormetic response characterized by an inverted U-shaped dose response in relation to total PCB liver burden. These results support several recent studies which report decreased levels of circulating corticosterone in PCB-exposed wild birds. The results presented here provide the first evidence that exposure to an environmentally relevant level of PCBs (approximately 10 mg/kg body weight) can impair the corticosterone stress response in kestrels, potentially increasing the susceptibility of birds to environmental stressors such as severe weather and predatory and human disturbance. 相似文献
90.
Many jail inmates have a history of substance use and "abuse"; few, however, receive comprehensive treatment for substance use disorders while in jail. The authors offer a longitudinal reanalysis of data from five jail-based substance user treatment programs. Survival analysis was used to identify client characteristics associated with length of time in treatment. Survival curves for the five programs were compared, indicating which ones retained inmates the longest. Results from a model stratified by jail site revealed that inmates over 25 years of age and those already sentenced had significantly longer treatment stays. The Substance Abuse Intervention Division (SAID) program, a modified therapeutic community in a New York jail, and the Deciding, Educating, Understanding, Counseling, and Evaluation (DEUCE) program, a curriculum-based intervention, had the longest survival curves and were, therefore, most effective at retaining inmates in treatment. 相似文献