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31.
In the cases of medical patients with sexually transmitted diseases (particularly those with the human immunodeficiency virus), two distinct approaches exist to notifying sexual and/or needle-sharing partners of possible risk. Each approach has its own history (including unique practical problems of implementation) and provokes its own ethical dilemmas. The first approach--the moral "duty to warn"--arose out of clinical situations in which a physician knew the identity of a person deemed to be at risk. The second approach--that of contact tracing--emerged from sexually transmitted disease control programs in which the clinician typically did not know the identity of those who might have been exposed. Confusion between the two approaches has led many to mistake processes that are fundamentally voluntary as mandatory and those that respect confidentiality as invasive of privacy. In the context of the AIDS epidemic and the vicissitudes of the two approaches, we describe the complex problems of partner notification and underscore the ethical and political contexts within which policy decisions have been made. 相似文献
32.
AS Harvey 《Journal of paediatrics and child health》2003,39(8):640-640
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34.
WF Paterson E McNeill S Reid AS Hollman MD Donaldson 《Archives of disease in childhood》1998,79(4):323-327
OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment. 相似文献
35.
Mutation of the p53 tumor suppressor gene in spontaneously occurring osteosarcomas of the dog 总被引:8,自引:0,他引:8
Inactivation of the p53 tumor suppressor gene has been implicated in the
pathogenesis of numerous human cancers, including osteosarcomas.
Appendicular osteosarcomas of the dog appear to be a good model for their
human equivalent with regard to biologic behavior, epidemiology and
histopathology. We individually screened exons 5-8 of the p53 gene for
mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to
compare the role of this gene in human and canine osteosarcoma
tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with
one tumor possessing two mutations within different exons. Of these, seven
were missense mutations and the eighth was a 'silent' mutation potentially
affecting the exon 6-7 splicing region. Five of the missense mutations were
located in highly conserved regions IV and V, while another corresponded
with the highly conserved codon 220 mutational hotspot located outside the
conserved domains. The locations and types of mutations were nearly
identical to those reported in human cancer. These findings provide strong
evidence of the involvement of p53 mutations in the development of canine
appendicular osteosarcomas. Canine osteosarcomas appear to be a promising
model for their human equivalent on a clinical, pathologic, and molecular
level.
相似文献
36.
One hundred patients of Diabetes Mellitus (70 with and 30 without clinical somatic neuropathy) were studied to correlate clinical severity with the magnitude of nerve conduction abnormalities. Age range was 10-79 years (mean 49) with equal number of males and females. Incidence of neuropathy was more in patients over 40 years of age (60 out of 70 patients) with duration of disease over two years (78.33%). The grades of severity were mild in 22 (31.33%), moderate in 25 (35.71%) and severe in 23 (32.86%) patients. Nerve conduction studies were carried out in 48 (27 with and 21 without clinical neuropathy) patients, using the apparatus Dantec (Cantata TM). The nerves (median, peroneal and sural) were stimulated at two points and the recording of latency; amplitude (micro V) and motor and sensory nerve conduction velocities (m/s) were done under identical environmental conditions. Sensory nerve conduction velocity was more affected than motor velocity. In the 21 patients without clinical neuropathy, 14 showed abnormalities indicating early involvement of peripheral nerves. Reduction of motor nerve conduction velocity was more in patients with moderate and severe grades. The reduction was more in lower than in upper limbs. Nerve conduction abnormality helps in diagnosis in diabetic neuropathy even in preclinical state and correlates with severity, in clinical neuropathy.KEY WORDS: Diabetic neuropathy, Nerve conduction abnormality, Peripheral neuropathy 相似文献
37.
Occult fractures of the scaphoid bone occur frequently and may lead to non-union. The use of three-phase bone scintigraphy in patients with normal x-rays of the scaphoid after carpal injury is widely advocated.In this study, 40 patients with negative radiographs but clinically suspected scaphoid fracture, all had rapid bone scintigraphy with images taken 15 min after intravenous injection of 99 m-Technetium Hydroxymethylene diphosphonate. The scan was performed approximately 2 weeks after the trauma. We found 8 fractures of the scaphoid bone and 13 fractures of other carpal bones. In 5 cases the images were inconclusive. At follow-up 6 months to 2 years later we found no patients with non-union.We find this rapid version of the bone scan useful as a second line investigation for continuing wrist pain following trauma in the presence of normal radiography. This can result in a reduction in both time and costs required for the diagnostic process. If the results are inconclusive we recommend a delayed image. CT or MRI could also be considered. In rare cases a wrist arthroscopy may be considered. 相似文献
38.
A systematic examination of the Chinese soft coral Dendronephthya sp. resulted in the isolation and characterization of 18 new cembranoid diterpenes, namely, dendronpholides A-R (2-19), along with 11-episinulariolide and an enantiomer of sandensolide. Their structures were determined through extensive spectroscopic (IR, MS, 2D NMR) data analyses and by comparison with those reported in literature. The cytotoxicity of several compounds against human tumor cell lines was also evaluated. 相似文献
39.
Bayer SR 《Fertility and sterility》2007,87(3):477-478
The movement towards international standardization of the terminology used to describe abnormal uterine bleeding and of the definition that sets the boundaries of normal menstrual bleeding will greatly benefit clinicians and researchers. 相似文献
40.