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Henyse G V Silva Rosangela P Tórtora Maria Lucia F Farias 《Gynecological endocrinology》2005,21(3):174-179
To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bone-specific alkaline phosphatase, markers of bone turnover, was seen during pregnancy ( p < 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients ( p < 0.05). TB BMD was positively correlated with LS BMD (r2 = 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied. 相似文献
74.
A C Da Rosa B Kemp T Paiva F H Lopes da Silva H A Kamphuisen 《Electroencephalography and clinical neurophysiology》1991,78(1):71-79
A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed. 相似文献
75.
The Barnes Hospital Apheresis Blood Collection and Blood Transfusion Unit is part of Barns Hospital Blood Bank. Because of its size and complexity, we report our experience which may be useful to administrators and physicians involved in the planning or management of similar services. From 1985 through 1988 we collected platelets from 1,976 different donors, the majority of which (87%) were community donors. Sixty-nine percent of 1,976 donors donated in 1988 an average of 4.9 times. Of 6,568 apheresis products collected. 1.1% were discarded because of positive screening tests and 0.7% were discarded because of outdating or presence of fibrin clot. In 1988 a total of nine cell separators were used. All donor apheresis were done with seven blood separators, and on average a separator produced an apheresis product every 4.5 worked hours. All therapeutic apheresis (338) were done on two separators. Most of them (88%) were performed during work hours. In 1988 donor and therapeutic apheresis were done by 17 1/2 full-time employees (FTEs) during work hours. Considering the Workload Unit Value per procedure given by the College of American Pathologists (CAP) and that each FTE worked 1,864 hours per year, the worked hour productivity for donor and therapeutic apheresis was 78.2%. Blood collections, therapeutic bleeds, and outpatient transfusions (1,127, 114 and 1,745 respectively) were accomplished by two FTEs, for a worked hour productivity of 35.5%. Because 95.1% of total worked units was produced by efficient donor and therapeutic apheresis activities, overall efficiency remained high at 73.8%. 相似文献
76.
Alcides José Branco Filho William Kondo Luis Sérgio Nassif Mariana Jorge Garcia Rafael de Almeida Tirapelle Carlos Marcelo Dotti 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(3):326-331
BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible. 相似文献
77.
78.
Sérgio Carreir?o Leandro Pereira Marcelo Wilson Rocha Almeida 《Aesthetic plastic surgery》2009,33(3):445-451
Surgical procedures for the mammary region currently are assuming an important role in body-contouring surgery. Enhancement
of results is a constant challenge to the plastic surgeon. A simple and efficient maneuver for resection of the breast’s lateral
pole based on the mammoplasty technique of Professor Ivo Pitanguy is described.
This study realized at the Private Clinic Sérgio Carreir?o, Rio de Janeiro, RJ, Brazil. 相似文献
79.
Luca Ramaglia Fabio Morgese Mariagiovanna Filippella Annamaria Colao 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):e30-e34
Gardner's syndrome (GS) is a hereditary disorder inherited as autosomal dominant with complete penetrance and variable expression. GS is a variant of familial adenomatous polyposis characterized by extracolonic manifestations including osteomas, dental anomalies, and epidermoid cysts. The association between GS and endocrine abnormalities has been well documented but a direct pituitary involvement has never been reported. We present a case of oral and maxillofacial manifestations in an adult patient affected by GS associated with growth hormone deficiency, a hitherto unreported association. The possible pathogenic mechanisms are discussed. 相似文献
80.
Mark A. Trimble Salvador Borges-Neto Stuart Smallhelser Ji Chen Emily F. Honeycutt Linda K. Shaw Jaekyeong Heo Robert A. Pagnanelli E. Lindsey Tauxe Ernest V. Garcia Fabio Esteves Frank Seghatol-Eslami G. Neal Kay Ami E. Iskandrian 《Journal of nuclear cardiology》2007,14(3):298-307
Background Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and
evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement
with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission
computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The
objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients
with left ventricular dysfunction, conduction delays, and ventricular paced rhythms.
Methods and Results A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images.
Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD,
bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction
(n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were
compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between
patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms
and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects
(P=.001).
Conclusions A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in
the evaluation of patients for CRT.
This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the
primary investigator. 相似文献