ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Most symptoms and signs of adrenal insufficiency are nonspecific yet common. Because the disorder is life threatening but very easy to treat, it is essential that it be accurately diagnosed. A test that is simple, inexpensive, and accurate is needed for this purpose. The tests available in the past were either expensive and not readily available (corticotropin‐releasing hormone), symptomatic and necessitating hospitalization (metyrapone or insulin tolerance), or not always reliable (ACTH stimulation). This last test, although easy to perform and inexpensive, uses extremely hyperphysiologic doses of ACTH to evaluate a physiologic response. This can cause false negative results, many of which are published in the literature. A physiological dose ACTH test, 1.0 &mgr;g, has been developed that is more sensitive than the original test in cases of mild adrenal insufficiency. It is also a very sensitive way to assess pituitaryadrenal suppression after long‐term treatment with glucocorticosteroids. In this situation, symptoms of the basic disease for which steroids were administered and withdrawal symptoms often complicate the picture. The 1.0 &mgr;g ACTH test is as sensitive as the insulin tolerance test and metyrapone tests and should be used as the screening test for adrenal insufficiency whenever such testing is indicated.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;It is now clear that calcium supplementation in postmenopausal women produces small but statistically significant benefits, leading to a slowing but not an arrest of bone loss. Studies in children and adolescents have demonstrated similar small gains in bone density of about 1–2% in most cases. In both age groups, these findings may be attributable, at least in part, to an “on‐off” effect resulting from the reduction in bone turnover rather than a change in long‐term rates of bone loss or accretion. In spite of this, several small recent studies suggest that fractures may be less common in those taking calcium supplementation but this will not be definitively established until the results of larger, longer term studies are available.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Acromegaly was first described as a specific entity in 1886 by Pierre Marie. One year later, Oscar Minkowski attiributed this disease to the presence of a pituitary tumor. Within the next 7 years surgery, and subsequently, pituitary irradiation, had been used for treatment. It took another 70 years to develop the first pharmacological agent for use in treatment, bromocriptine, and by mid‐1980s, a long‐acting somatostatin analog, octreotide, was introduced into clinical trials. Over the past 100 years much has been learned about the nature of acromegaly. Every patient with this disease presents clinical and physiological challenges. In this article, controversies in the current knowledge about the diagnosis and therapy of acromegaly will be addressed.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Neuroendocrine cells throughout the body express somatostatin receptors. These receptors are generally overexpressed on neuroendocrine tumor cells. Octreotide, a somatostatin analogue, has a high affinity for a population of somatostatin receptors on neuroendocrine cells. By radiolabeling octreotide or other analogues, scintigraphy can localize tumors based on the abnormal density of somatostatin receptors expressed by tumor cells versus background. Currently, somatostatin receptor scintigraphy is used to localize carcinoid tumors, islet cell tumors, pheochromocytomas and paragangliomas. New applications for somatostatin receptor scintigraphy await the development of receptor subtype‐specific analogues and additional radioligands.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Hypergonadotropic hypogonadism or premature ovarian failure is not that uncommon. Approximately 1% of the reproductive age population are affected. The presentation is heterogeneous with a wide variety of etiologies. The multiple causes include autoimmune, genetic, iatrogenic, infection, enzymatic deficiencies, and idiopathic. The mechanism for the lack of ovarian function is poorly understocd. The diagnostic approach to these patients requires a detailed history and thorough physical exam to help identify a potential etiology for the disease process. A variety of diagnostic tests can be performed dependent on suspected etiologies. Simple blood tests should be performed to rule out evidence of autoimmune polyglandular failure. A karyotype should be performed in any patient presenting with primary ovarian failure. Treatment has been empiric hormone replacement with estrogen and progesterone. For those patients desiring pregnancy, ovulation induction has not been successful although pregnancies have been reported in the literature. In the age ofin vitrofertilization, oocyte donation has become a reality and a successful option for young women who are affected by premature ovarian failure.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;A recently published report of a study that claims to demonstrate bioequivalence between branded and generic levothyroxine products has been the center of a minor storm of controversy related to several issues. Prominent among these have been issues of suppression by industry of data unfavorable to their products, as well as their possible interference with academic freedoms and the time‐honored peer review process. In all of the excitement over the latter issue, the fact that the study itself appears to be significantly flawed in both its design and its execution may have been lost. Publication of the study in spite of its apparent flaws was viewed by the journal's editors as a conscientious act, but can be criticized in view of the study's faults and of the fact that the study, now 5 years old, was based on outmoded parameters, and its conclusions and inferences had been seriously questioned in another previously published analysis of the same data. In view of the importance of thyroxine bioequivalence in terms of both the economics and quality of health care to millions of thyroid patients, the study is critiqued and its history reviewed. The difference between classic bioequivalency studies and those based on the pharmacodynamics of TSH response is described as is the paucity of TSH data in the report. Even assuming that bioequivalence had been proven, albeit by outmoded FDA guidelines, a conclusion as to therapeutic interchangeableness would be premature and unfounded. In view of these uncertainties, it is clear that better designed and executed studies will be required before it can be concluded that therapeutic interchange between any of the branded and generic levothyroxine preparations could be advised. The genesis of the controversy surrounding the data in the study and other considerations that could impact both clinical and research thyroidology are also discussed.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Open access health plans are demonstrating the fastest growing enrollment in the marketplace. Managed care organizations are shifting away from the gatekeeper model of cost‐containment toward other methods such as provider profiling for resource consumption and capitation of specialists. With reduced demand for services, many specialists are competing with primary care physicians for patients. Confusion abounds regarding what constitutes a minimum standard of primary care management and when it is appropriate to refer. Regardless of the cost‐containment methods used, financial incentives applied in the absence of clinical appropriateness criteria may result in implicit rationing of health care. Software‐embedded clinical criteria are essential to measure clinical performance, maintain provider skill, enable appropriate clinical decisions, and support efficient division of labor among generalists and specialists.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

&NA;Von Hippel‐Lindau disease (VHL) is a heritable constellation of visceral, retinal, and central nervous system tumors transmitted in an autosomal dominant manner. These manifestations, some of them life‐threatening, are often multifocal and may become clinically apparent at a young age. Pheochromocytoma occurs in 10 to 19% of affected individuals. The patients described in this report illustrate that pheochromocytoma may be the initial clinical manifestation of VHL disease. These observations strongly suggest that a diagnosis of VHL disease should be entertained in all pheochromocytoma patients. This consideration will lead to early diagnosis and treatment of affected patients and should decrease the morbidity and mortality associated with this devastating familial disease.

ISSN:1051-2144    

出版商:OVID    

年代:1997

数据来源: OVID