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151.
Spontaneous hematomas are rare and can present with acute or chronic symptoms. Our patient presented with deep vein thrombosis of the lower extremity associated with a spontaneous pelvic hematoma. This lesion was radiologically and clinically indistinguishable from a soft-tissue neoplasm. The case of a spontaneous pelvic neoplasm in an otherwise healthy young man is presented and the literature reviewed regarding issues of differential diagnosis and clinical management. 相似文献
152.
DC Park C Hertzog H Leventhal RW Morrell E Leventhal D Birchmore M Martin J Bennett 《Canadian Metallurgical Quarterly》1999,47(2):172-183
OBJECTIVES: To create a profile of individuals nonadherent to their medications in an age-stratified sample (ages 34-84) of community-dwelling rheumatoid arthritis patients. The relative contributions of age, cognitive function, disability, emotional state, lifestyle, and beliefs about illness to nonadherence were assessed. DESIGN: A direct observation approach was used in conjunction with structural equation modeling. All participants were administered a preliminary assessment battery. Medications were then transferred to vials with microelectronic caps that recorded medication events for all medications for the next 4 weeks. PARTICIPANTS AND SETTING: A volunteer sample of 121 community-dwelling rheumatoid arthritis (RA) patients were recruited from newspaper ads, posters, and via informal physician contact from private rheumatology practices in Atlanta and Athens, Georgia. Written verification of the RA diagnosis and a disease severity rating were obtained from personal physicians before patients were enrolled in the study. Patients were tested in a private physician's office, and their medication adherence was monitored electronically for a month in their every-day work and home settings. MEASUREMENTS AND RESULTS: Structural equation modeling techniques were used to develop a model of adherence behavior. Cognitive and psychosocial measures were used to construct latent variables to predict adherence errors. The model of medication adherence explained 39% of the variance in adherence errors. The model demonstrated that older adults made the fewest adherence errors, and middle-aged adults made the most. A busy lifestyle, age, and cognitive deficits predicted nonadherence, whereas coping with arthritis-related moods predicted adherence. Illness severity, medication load, and physical function did not predict adherence errors. Omission of medication accounted for nearly all errors. CONCLUSION: Despite strong evidence for normal, age-related cognitive decline in this sample, older adults had sufficient cognitive function to manage medications. A busy lifestyle and middle age were more determinant of who was at risk of nonadherence than beliefs about medication or illness. Thus, practicing physicians should not assume that older adults have insufficient cognitive resources to manage medications and that they will be the most likely to make adherence errors. Very busy middle-aged adults seem to be at the greatest risk of managing medications improperly. 相似文献
153.
JV Fleming P Barrett SL Coon DC Klein PJ Morgan 《Canadian Metallurgical Quarterly》1999,140(2):972-978
The enzyme arylalkylamine N-acetyltransferase (AANAT; EC 2.3.1.87) has been conventionally linked with the biosynthesis of melatonin within the pineal gland and retina. This study establishes that AANAT messenger RNA (mRNA) and functional enzyme occurs within the pars tuberalis (PT) and to a lesser degree within the pars distalis (PD) of the sheep pituitary gland; expression in these tissues is approximately 1/15th (PT) and 1/300th (PD) of that in the ovine pineal gland. AANAT mRNA in the PT appears to be expressed in the same cells as the Mel1a receptor. No evidence was obtained to indicate that either PT or PD cells have the ability to synthesize melatonin, suggesting that this enzyme plays a different functional role in the pituitary. We also found that cAMP regulation of the abundance of AANAT mRNA differs between the PT and pineal gland. Forskolin (10 microM) has no effect on pineal AANAT mRNA levels, yet represses expression in the PT. This suppressive influence could be mediated by ICER (inducible cAMP response early repressor), which is induced by forskolin in both tissues. Although it appears that the specific function and regulation of AANAT in the pituitary gland differ from that in the pineal gland, it seems likely that AANAT may play a role in the broader area of signal transduction through the biotransformation of amines. 相似文献
154.
PURPOSE: We identified the incidence and types of genital and urinary anomalies, and established a plan for evaluating the urinary system in the CHARGE association. MATERIALS AND METHODS: We retrospectively reviewed the charts of 32 patients in whom the CHARGE association was diagnosed. RESULTS: Of the 32 patients identified 22 (69%) had genitourinary abnormalities. Genital anomalies, including micropenis, penile agenesis, hypospadias, chordee, cryptorchidism, a bifid scrotum, atresia of the uterus, cervix and vagina, and hypoplastic labia majora, labia minora and clitoris, were present in 18 patients (56%). Of the 24 patients who underwent renal ultrasound 10 (42%) were diagnosed with urinary tract anomalies including a solitary kidney, hydronephrosis, renal hypoplasia and duplex kidneys. Further evaluation revealed vesicoureteral reflux, neurogenic bladder secondary to spinal dysraphism, nephrolithiasis, ureteropelvic junction obstruction and a nonfunctioning upper pole in both duplex kidneys. CONCLUSIONS: There is a high incidence of genitourinary anomalies in the CHARGE association. Because of this high incidence of anomalies, patients with this condition should undergo a careful genitourinary evaluation, including renal and bladder ultrasound, and voiding cystourethrography screening. 相似文献
155.
Diffusion of antibody protein from hydrogel films and hydrogel encapsulated in a microcapillary was studied. Thin hydrogel films were formed by crosslinking 6-acryloyl-B-O-methylgalactoside with N,N'-methylene-bis-acrylamide and the diffusive transport of monoclonal antimouse IgG-FITC into and out of the hydrate films was measured. Diffusion coefficients in 2 and 4% crosslinked hydrogel films were measured. The measured diffusion constants determined for IgG in both the 2 and 4% hydrogel films were comparable to the free diffusion of IgG in bulk water (Dmean approximately 10(-7) cm2/s). In addition, 2% crosslinked hydrogels were prepared in a capillary tube and the transport of antimouse IgG-FITC into and out of the hydrated hydrogel was measured. Kinetic analysis indicated that the protein transport through the capillary hydrogel was faster than would be expected for a simple diffusion process. Finally, by utilizing the diffusion of antibody from the capillary hydrogel, transfer of antibody to a silica surface was demonstrated. A capillary hydrogel loaded with antimouse IgG-FITC was used to transfer the protein to a silica surface forming a 30-micron spot of antibody, which was imaged using fluorescence microscopy. These results may lead to the development of a nonlithographic method of patterning antibodies on surfaces for use in integrated microimmunosensors. 相似文献
156.
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158.
Meiotically driven sex chromosomes can quickly spread to fixation and cause population extinction unless balanced by selection or suppressed by genetic modifiers. We report results of genetic analyses that demonstrate that extreme female-biased sex ratios in two sister species of stalk-eyed flies, Cyrtodiopsis dalmanni and C. whitei, are due to a meiotic drive element on the X chromosome (Xd). Relatively high frequencies of Xd in C. dalmanni and C. whitei (13-17% and 29%, respectively) cause female-biased sex ratios in natural populations of both species. Sex ratio distortion is associated with spermatid degeneration in male carriers of Xd. Variation in sex ratios is caused by Y-linked and autosomal factors that decrease the intensity of meiotic drive. Y-linked polymorphism for resistance to drive exists in C. dalmanni in which a resistant Y chromosome reduces the intensity and reverses the direction of meiotic drive. When paired with Xd, modifying Y chromosomes (Ym) cause the transmission of predominantly Y-bearing sperm, and on average, production of 63% male progeny. The absence of sex ratio distortion in closely related monomorphic outgroup species suggests that this meiotic drive system may predate the origin of C. whitei and C. dalmanni. We discuss factors likely to be involved in the persistence of these sex-linked polymorphisms and consider the impact of Xd on the operational sex ratio and the intensity of sexual selection in these extremely sexually dimorphic flies. 相似文献
159.
160.