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Most studies of exercise-induced amenorrhea have compared amenorrheic athletes (usually runners) with sedentary control subjects. Such comparisons will identify hormonal changes that develop as a result of exercise training but cannot determine which of these changes play a role in causing amenorrhea. To obviate this problem, we assessed reproductive hormone status in a group of five amenorrheic runners and compared them to a group of six eumenorrheic runners matched for body fatness, training intensity, and exercise performance. Compared to the eumenorrheic runners, the amenorrheic runners had lower serum estradiol concentrations, similar basal serum luteinizing hormone and follicle-stimulating hormone concentrations, and exaggerated responses of serum gonadotropins after administration of luteinizing hormone-releasing hormone (100 micrograms intravenous bolus). Serum prolactin levels, both basally and after thyrotropin-releasing hormone administration (500 micrograms intravenous bolus) or treadmill exercise, was similar in the two groups, as were serum thyroid function tests (including thyrotropin response to thyrotropin-releasing hormone). Changes in serum cortisol levels after short-term treadmill exercise were similar in both groups, and serum testosterone levels increased after exercise only in the eumenorrheic group. In neither group did such exercise change serum luteinizing hormone, follicle-stimulating hormone, or thyrotropin levels. We concluded that exercise-induced amenorrhea is not solely related to the development of increased prolactin output after exercise training. The exaggerated gonadotropin response to luteinizing hormone-releasing hormone seen in amenorrheic runners in comparison with matched eumenorrheic runners is consistent with a hypothalamic etiology for the menstrual dysfunction, analogous to that previously described in "stress-induced" or "psychogenic" amenorrhea.  相似文献   
66.
Magnesium sulfate, an agent whose cellular actions might cause metabolic disturbances, has been used concomitantly with ritodrine hydrochloride for preterm labor tocolysis. Although the profound metabolic effects of beta-adrenergic agents have been well described, the possibility that adjunctive magnesium might cause further or unexpected alterations in maternal metabolic parameters has not been fully evaluated. To investigate this question, we prospectively randomized patients, in a blinded fashion, to receive ritodrine plus placebo or ritodrine plus adjunctive magnesium sulfate for preterm labor tocolysis. Serial measurements of potassium, glucose, blood urea nitrogen, and hematocrit were obtained and compared between tocolytic treatment groups. The metabolic changes found were similar in each group and appear to result predominantly from beta-adrenergic stimulation with no apparent perturbations caused by the direct cellular actions of magnesium sulfate. From the metabolic standpoint, it appears that the clinician may use adjunctive magnesium sulfate without fear of accentuating or obscuring the expected beta-adrenergic-induced alterations in the above-mentioned maternal metabolic parameters.  相似文献   
67.
"RSI": putting the epidemic to rest   总被引:4,自引:0,他引:4  
  相似文献   
68.
Bilateral coronoid hyperplasia in two brothers   总被引:1,自引:0,他引:1  
Coronoid hyperplasia is a rare condition of unknown aetiology that can occur in both unilateral and bilateral forms. Without radiographic investigation the diagnosis is often missed. Researchers have postulated a familial form of inheritance. This study reports the occurrence of coronoid hyperplasia in two brothers. The parents were unaffected and there are no other siblings. The diagnosis was confirmed with the aid of panoramic radiographs and axial computed tomographic scans with para-sagittal reconstructions which demonstrated enlargement of the coronoid processes and in one case impingement against the zygomatic bone. One brother was successfully treated with a unilateral intra-oral coronoidectomy whilst the other was unsuccessfully treated with a bilateral intra-oral coronoidectomy.  相似文献   
69.
These studies examined the effect of the lymphokine interleukin-2 (IL-2) on porcine peripheral blood lymphocytes (PBL). Cultures of porcine (Yorkshire) PBL in human recombinant (r) IL-2 had a time-dependent increase in activation of killer cells. Previous reports of porcine killer cells derived from PBL indicated maximal lysis 18 hr after killer and target cells were mixed, with very little lytic activity at 4 hr. After culturing for 2 days in rIL-2, the cells acquire enhanced lytic capabilities resulting in substantial target lysis in the 4-hr assay. Enhanced lytic activity in the 18 hr assay occurs as early as 30 min after exposure to rIL-2, with a more significant increase after 2 days' exposure. The IL-2-treated cells have an increase in the incorporation of tritiated thymidine and an increase in percentage of granular cells. Tumour targets, such as Daudi, which are resistant to lysis, and L929, Mdt4 and P815, which are moderately susceptible to lysis by untreated swine PBL, had a substantial increase in lysis in IL-2-treated swine PBL. These results indicate human rIL-2 induces functional and morphological changes in swine peripheral blood lymphocytes.  相似文献   
70.
The technical aspects of radial artery harvesting.   总被引:2,自引:0,他引:2  
We describe our technique for harvesting the radial artery for coronary revascularization. Anatomy and preoperative preparation are also presented, as well as the history of the radial artery as a bypass conduit, the advantages, and some contraindications. We have found that, with proper harvesting, the radial artery is an effective means of coronary artery revascularization.  相似文献   
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