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91.
Previously reported attenuation of skin postural vasoconstriction in women during the luteal menstrual cycle phase may be
due to a progesterone-mediated decrease in myogenic or veno-arteriolar (VAR) mechanisms. Skin perfusion was measured in the
shin and foot dorsum by Laser Doppler Fluxometry during leg dependency that increased vascular transmural pressure below (myogenic
constriction only) and above (myogenic and VAR) the 25 mmHg threshold for activation of the VAR, and during venous distension
to activate the VAR alone (cuff inflation to 50 mmHg). In six young women with normal menstrual cycles, vasoconstrictor responses
to all interventions did not differ between days 7–13 (follicular) and 18–23 (luteal) of the normal menstrual cycle when progesterone
levels were low and at their peak respectively. In eight women taking combined oral contraceptives (OC) and tested during
pill consumption days, reductions in foot skin perfusion were smaller (P = 0.05) than in the luteal phase of the normal cycle for leg dependency below (−36.9 ± 5.2% OC vs. −52.5 ± 7.8% luteal, mean ± S.E.M.)
and above (−43.7 ± 3.4% OC vs. −55.1 ± 4.8% luteal) the VAR threshold, and for venous distension (−53.1 ± 2.6% OC vs. 66.4 ± 5.5%
luteal). In women with normal menstrual cycles, impaired postural vasoconstriction may be confined to those who experience
pre-menstrual symptoms rather than a direct effect of endogenous hormones. Reduced vasoconstriction in the dependent foot
during OC use is consistent with the known vasodilator action of exogenous hormones and its long-term effects 相似文献
92.
Péter Móricz Imre Gerlinger Jenő Solt Krisztina Somogyvári József Pytel 《European archives of oto-rhino-laryngology》2007,264(12):1441-1445
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy
and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic
balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases.
In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The
average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature
data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every
effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major
myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap
needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free
flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in
prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and
neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter
dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure
provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However,
a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion
of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications. 相似文献
93.
Nelson Wolosker Guilherme Yazbek José Ribas Milanez de Campos Paulo Kauffman Augusto Ishy Pedro Puech-Leão 《Clinical autonomic research》2007,17(3):172-176
Background Sympathectomy is the treatment of choice for primary hyperhidrosis. One curious occurrence that is difficult to explain from
an anatomophysiological point of view in cases of video-assisted thoracoscopic sympathectomy (VATS) for the treatment of palmar
hyperhidrosis (PH) is the observed improvement in plantar hyperhidrosis (PLH). Nevertheless, current reports on VATS rarely
describe the effect on PLH or just give superficial data. The aim of this study was to prospectively investigate, how surgery
affects PLH in patients with PH and PLH over one-year period.
Methods From May 2003 to January 2004, 70 consecutive patients with combined PH and PLH underwent VATS at the T2, T3, or T4 ganglion
level (47 women and 23 men, with mean age of 23 years).
Results Immediately after the operation, all the patients said they were free from PH episodes, except for two patients (2.8%) who
suffered from continued PH. Compensatory hyperhidrosis (CH) of various degrees was observed in 58 (90.6%) patients after one
year. Only 13 (20.3%) suffered from severe CH. There was a great initial improvement in PLH in 50% of the cases, followed
by progressive regression, such that only 23.4% still presented that improvement after one year. The number of cases without
overall improvement increased progressively (from 17.1% to 37.5%) and the numbers with slight improvement remained stable
(32.9–39.1%). Of the 24 patients with no improvement after one year, 6 patients graded plantar sweating worse.
Conclusion Patients with PH and PLH who undergo VATS to treat their PH present a good initial improvement in PLH that reduces to a lower
level of improvement after the one-year period. 相似文献
94.
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed.
Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis
or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance.
Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various
ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their
radiologic differential diagnoses and pitfalls.
Received: 22 February 2001/Accepted: 18 April 2001 相似文献
95.
Background: Although managed care organizations (MCOs) may be optimal settings for implementing tobacco use cessation clinical guidelines,
such guidelines remain poorly implemented in many MCO settings.Purpose: We examined issues related to the implementation of guidelines in MCOs, to provide examples of studies that have addressed
issues related to guideline implementation and to suggest ways behavioral medicine researchers can play a role in examining
issues of how guidelines can be better implemented.Methods: Surveys of clinical guideline implementation, studies from the Robert Wood Johnson Foundation addressing tobacco use cessation
in a managed care database, selected to illustrate issues related to system-wide implementation.Results: Surveys show that effective tobacco use cessation interventions remain underutilized in MCOs. A few studies have evaluated
and shown the benefit of insurance coverage for tobacco use and dependence treatments, clinician reimbursement and leadership
incentives, practice feedback, and leveraging administrative data to create tobacco use tracking systems. The studies also
point to the need for large-scale, multidisciplinary, methodologically rigorous studies that allow one to isolate the effects
of promising strategies as well as to explore synergistic effects as different system changes are combined.Conclusions: Tobacco use cessation guidelines need to be better implemented in MCOs. Behavioral medicine research needs to move beyond
treatment efficacy and effectiveness studies to focus on rigorous evaluations of these and other strategies to enhance guideline
implementation and dissemination.
This research was supported by grants from the Tobacco-Related Disease Research Program (Taylor) and from the Robert Wood
Johnson Foundation (Taylor and Curry). 相似文献
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