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排序方式: 共有1619条查询结果,搜索用时 15 毫秒
61.
B M Biller J F Coughlin V Saxe D Schoenfeld D I Spratt A Klibanski 《Obstetrics and gynecology》1991,78(6):996-1001
Hypothalamic amenorrhea, a common disorder associated with abnormalities in gonadotropin pulsatility and subsequent estrogen deficiency, is usually transient, and treatment indications are unclear unless fertility is desired. To determine whether this disorder is associated with progressive bone loss, we studied 24 women with primary or secondary amenorrhea related to stress or simple weight loss, compared with 31 normal women of the same age. Amenorrheic women had significantly lower (P = .01) body fat (26.4 +/- 7.3 versus 30.6 +/- 4.7%) and higher (P = .0001) urine free cortisol levels (250 +/- 100 versus 140 +/- 50 nmol/day) than normals. Trabecular bone density in women with hypothalamic amenorrhea as assessed by spinal computed tomography was significantly (P = .001) lower than in normals (140.2 +/- 27.3 versus 175.1 +/- 24.6 mg K2HPO4/mL, respectively). Twenty of the 24 amenorrheic women had initial spinal bone density below the mean in normals, and in eight it was 2 standard deviations or more below the normal mean. Initial bone density correlated negatively with duration of amenorrhea (r = -0.489, P = .02) and positively with serum free testosterone levels (r = 0.517, P = .02). Prospective evaluation showed a decline in spinal bone density in those who were amenorrheic for fewer than 5 years. The slope of change in bone density correlated with initial weight, percent ideal body weight, and percent body fat (R2 = 0.597, P = .0003; R2 = 0.549, P = .0007; and R2 = 0.618, P = .0002, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
62.
DC Wilson MJ Cunningham MMcC Reid SS Johnston TF Fannin 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(1):84-85
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis. 相似文献
63.
64.
Fitzner KA Coughlin S Tomori C Bennett CL 《Health policy (Amsterdam, Netherlands)》2000,53(3):147-155
Hong Kong and Mainland China are undertaking health reform following recent economic fluctuations and Hong Kong's transformation to a Special Administrative Region of China in 1997. Despite spending only 4.7% of its Gross Domestic Product on health care, one third as much as in the United States, Hong Kong has developed health statistics comparable to those in leading western nations. In contrast, Mainland China's 3.6% of GDP expenditure on health is associated with health statistics and expenditures similar to those found in most developing countries. Hong Kong has adopted health care financing and organizational health systems that are commonly seen in centrally planned economies, while its economy functions as a highly capitalistic enterprise. In contrast, mainland China has integrated many features of health care systems associated with market economies, while its overall economy is largely centrally planned. In this paper we examine the policy factors associated with these disparate health systems and investigate whether they can be maintained according to the 'one country, two systems' approach that has been adopted by Chinese policy makers. 相似文献
65.
66.
Unlike arterial disease, most vascular surgeons have very little experience in performing bypass procedures for venous obstruction especially when occurring in children. Given the lack of published literature when compared to arterial procedures, we report a successful venous crossover procedure following iatrogenic injury and subsequent occlusion of the right common femoral vein in a nine year old boy. 相似文献
67.
Saluja S Sato N Kawamura Y Coughlin W Putman CM Spencer DD Sze G Bronen RA 《AJNR. American journal of neuroradiology》2000,21(9):1650-1653
BACKGROUND AND PURPOSE: Postoperative contrast-enhanced MR imaging of the brain is routinely used when evaluating for residual or recurrent brain tumor. It is imperative to be aware of morphologic changes and imaging features that typically occur in response to surgical manipulation at the postoperative site to avoid misinterpretation of imaging findings. Our purpose was to determine normal postoperative changes and alterations in the choroid plexus among patients who had undergone temporal lobectomy in order to distinguish this appearance from pathologic changes that may be seen in the presence of infection or recurrent tumors. METHODS: We reviewed 159 MR scans from 95 patients with hippocampal sclerosis or gliosis who underwent temporal lobectomy for treatment of intractable epilepsy. Choroid plexus location and size were assessed on contrast-enhanced T1-weighted images. RESULTS: After temporal lobectomy, the choroid plexus enlarged and sagged into the resection site. Increase in the size of the choroid plexus occurred in 58% of cases overall. The degree of enhancement also increased after surgery, sometimes resulting in a nodular pattern of enhancement. The changes were most marked during the 1st week after temporal lobectomy, and showed an enlarged, markedly enhancing choroid plexus on 86% of the scans. CONCLUSION: Postoperative changes of the choroid plexus after temporal lobectomy include sagging into the resection site, an increased size, and an increased degree of enhancement. Normal postoperative morphologic characteristics may mimic neoplastic enhancement pattern. Familiarity with this appearance is important to avoid a pitfall in diagnosis of recurrent postoperative temporal lobe neoplasms. 相似文献
68.
Coughlin MJ 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2000,21(11):896-905
A retrospective review was performed on industrial patients who sustained calcaneal fractures within the State of Idaho during the years 1992 to 1994, and these patients were insured by the Idaho State Insurance Fund. Of 48 calcaneal fractures that occurred during this period, 18 were non-displaced extra-articular fractures and 30 were displaced intra-articular fractures. An independent evaluator contacted each patient and performed chart reviews regarding the work history, period of time off work, and cost incurred with the injury. A total of 24 primary surgical procedures were performed on patients who sustained a displaced intra-articular calcaneal fracture and 31 secondary procedures were performed including wound debridement, hardware removal, skin grafting, and secondary subtalar fusion. For patients whose calcaneal fractures could be treated with non-operative care, the average time from injury until return to work was 18 weeks, and the average total cost of injury was $14,230. For patients whose calcaneal fractures required open reduction and internal fixation, the average time loss from work was 35 weeks, and the average total cost of injury was $31,004. Seven patients whose calcaneal fractures were initially treated with an open reduction, internal fixation later underwent a hindfoot arthrodesis. The average time off work for these patients was 69 weeks and the average total cost of injury was $65,384. Fractures were rated on postoperative radiographs according to the quality of their operative reduction. Fractures that were non-anatomically reduced had an increased tendency to require a subtalar fusion. Nine patients sustained other injuries associated with their calcaneal fracture and three patients sustained an open fracture. Both concurrent injuries and open fractures were associated with increased total cost and increased time off work. The total cost of injury was doubled as was time off work when an open reduction and internal fixation was followed later by a secondary subtalar arthrodesis. 相似文献
69.
Coughlin MJ Dorris J Polk E 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2000,21(2):94-104
Sixty-three patients (118 toes) were evaluated at an average 61 month follow-up following PIP resection arthroplasty for a fixed hammertoe deformity. The deformity involved the second toe in 35%, the third toe in 21%, the fourth toe in 24%, and the fifth toe in 20%. The involved toe averaged 2 mm. greater length than the adjacent toes and was longer in 49/94 (52%). Seventy-eight percent of patients complained of pain preoperatively due to the hammertoe deformity and 49% complained of callus formation. Following a resection arthroplasty technique with intramedullary Kirschner wire fixation, fusion of the PIP joint occurred in 81% of toes. A fibrous union resulted in the remaining 19% of cases. Patients rated subjective alignment as acceptable in 86% of cases and radiographic alignment was rated as good in 79%. Malalignment and numbness were the major factors associated with an unsuccessful result. Pain was relieved in 92%of patients and subjective satisfaction was noted by 84% of patients. Minor complications occurred in 5%. The average postoperative AOFAS score was 83 points. Resection arthroplasty of the proximal interphalangeal joint with intramedullary Kirschner wire fixation as a technique for correction of a fixed hammertoe deformity is a reliable technique that consistently gives a high level of satisfactory results. 相似文献
70.
Evidence for endogenous formation of tobacco-specific nitrosamines in rats treated with tobacco alkaloids and sodium nitrite 总被引:2,自引:0,他引:2
Carcinogenic tobacco-specific nitrosamines are present in tobacco products
and are believed to play a significant role in human cancers associated
with tobacco use. Additional amounts of tobacco-specific nitrosamines could
be formed endogenously. We tested this hypothesis by treating rats with
nicotine and sodium nitrite and analyzing their urine. Initially, we
treated groups of rats with (S)-nicotine (60 micromol/kg) and NaNO2 (180
micromol/kg), (S)-nicotine alone, NaNO2 alone or
4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 12 nmol/kg) by gavage
twice daily for 4 days. We collected urine and analyzed for two metabolites
of NNK; 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanol and its glucuronide.
We did not detect these metabolites in the urine of rats treated with
nicotine alone or nicotine plus NaNO2, indicating that endogenous
conversion of nicotine to NNK did not occur. However, the urine did contain
N'- nitrosonornicotine (NNN), N'-nitrosoanabasine (NAB) and N'-
nitrosoanatabine (NAT). Analysis of the (S)-nicotine used in this
experiment demonstrated that it contained trace amounts of nornicotine,
anabasine and anatabine. In a second experiment, we used an identical
protocol to compare the endogenous nitrosation of this (S)-nicotine with
that of synthetic (R,S)-nicotine, which did not contain detectable amounts
of nornicotine, anabasine or anatabine. NNN (0.53 x 10(-3)% of nicotine
dose), NAB (0.68%) and NAT (2.1%) were detected in the urine of the rats
treated with the (S)-nicotine and NaNO2. NNN (0.47 x 10(- 3)% of dose), but
not NAB or NAT, was present in the urine of the rats treated with synthetic
(R,S)-nicotine and NaNO2. NNN probably formed via nitrosation of
metabolically formed nornicotine. These results demonstrate for the first
time that endogenous formation of tobacco- specific nitrosamines occurs in
rats treated with tobacco alkaloids and NaNO2. The potential significance
of the results with respect to nitrosamine formation in people who use
tobacco products or nicotine replacement therapy is discussed.
相似文献