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71.
Mark W. Vander Weg Robert C. Klesges Linda H. Eck Clemens Andrew W. Meyers Randy W. Pascale 《International journal of behavioral medicine》2001,8(2):163-177
Although weight gain is a well-established consequence of quitting smoking, the energy balance mechanisms responsible for
postcessation weight gain are not clear. Furthermore, although gender and ethnicity are important predictors of postcessation
weight gain, no studies have evaluated the effects of these variables on changes in energy balance. This study investigated
short-term changes in energy balance following smoking cessation in 95 smokers. In as little as 2 weeks, smoking cessation
was associated with a significant increase in body weight (1.05 kg). Smoking cessation was also associated with an increase
in energy intake (1440 kJ/day), and no changes in energy expenditure (physical activity; resting energy expenditure, REE)
were observed. Changes in body weight and energy balance did not differ by gender or ethnicity. Predictors of weight gain
included baseline carbon monoxide (CO) level, baseline REE per kg of body weight, and changes in energy intake. These findings
provide valuable information about the mechanisms responsible for at least the early stages of postcessation weight gain.
Support for this study was providedby Grant No. HL46352 from the National Heart, Lung and Blood Institute. 相似文献
72.
William T. Dalton III Lisa M. Klesges Laura Henderson Grant Somes Leslie Robinson Karen C. Johnson 《Addictive behaviors》2010
Treatment studies provide minimal support for nicotine replacement therapy (NRT) with youth; however, survey studies suggest that adolescents use NRT, and may engage in inappropriate use. The current study sought to examine patterns of NRT use and risk factors for use to further aid smoking cessation efforts including prevention of potential misuse. In-school surveys assessing socio-demographic and behavioral factors associated with NRT use, gum or patch, were completed by 4078, predominantly African American, high school students. Approximately 5% of students reported former or current use of NRT products: 42% gum, 29% patch, and 29% both gum and patch. Among smokers, 5.4% reported use of both NRT gum and patch, with exclusive use of gum twice as likely as exclusive use of the patch. Those with high-risk-taking attitudes were more likely than low-risk takers (3% vs. 1%) to report use of both products, with exclusive gum use more prevalent than patch use. A cumulative logit model revealed males, risk takers, and/or smokers were at greatest odds for NRT use. Among this adolescent sample, NRT gum was used more often than the patch. Adolescent males, risk takers, and/or smokers appear more likely to use NRT (gum and/or patch) compared to their counterparts, despite limited empirical support for effective use of these products as cessation aids among adolescents. Smoking cessation and prevention programs may emphasize appropriate NRT use, specifically within these populations. 相似文献
73.
Prostatic evaluation by transrectal sonography with histopathologic correlation: the echopenic appearance of early carcinoma 总被引:6,自引:0,他引:6
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed. 相似文献
74.
Aoki S; Okada Y; Nishimura K; Barkovich AJ; Kjos BO; Brasch RC; Norman D 《Radiology》1989,172(2):381-385
Magnetic resonance (MR) images of the brain in 285 patients between the ages of 2 and 25 years were retrospectively studied to determine the appearance of brain iron accumulation. The globus pallidus, red nucleus, substantia nigra, and dentate nucleus were evaluated with long TR/TE (repetition time/echo time) spin-echo sequences and staged. All four regions in most patients were initially hyperintense compared with white matter (stage I) before becoming isointense (stage II) and subsequently hypointense (stage III). The globus pallidus was the first to reach stage III, the red nucleus and substantia nigra were next, and the dentate nucleus was last. In general, decreased signal intensity (stage III) was not seen in these regions in patients less than 10 years old; in most patients it was seen by age 25 years. The dentate nucleus decreased in signal intensity more slowly and inconsistently; only one-third of patients had reached stage III by age 25 years. The temporal sequence of normal iron deposition as detected with MR imaging is helpful not only in the diagnosis of known iron-deposition diseases but also in the detection of iron-related pathologic changes. 相似文献
75.
Tartrate-resistant acid phosphatase (TRAcP) is used as a marker for osteoclasts, which are believed to be derived from phagocytic cells or phagocyte stem cell precursors. To further investigate the relationship between monocytic phagocytes and osteoclasts, acid phosphatase (AcP) activity was measured by three different techniques in human peripheral blood monocytes, monocyte-derived macrophages, and the U937 cell line. We found that cytochemistry and gel electrophoresis led to similar results, but that the colorimetric assay was inconsistent. Normal human peripheral monocytes expressed both tartrate-sensitive and -resistant AcP. In culture these cells formed polykaryons and expressed TRAcP activity that was further identified as an isoenzyme associated with bone tissue. In contrast, the U937 cells did not express TRAcP activity as measured by gel electrophoresis. Both U937 cells and monocytes possess material that interferes with interpretation of the colorimetric assay of AcP. The presence of TRAcP in monocyte-derived macrophages further supports the relationship between phagocytic cells and bone osteoclasts. 相似文献
76.
77.
L Cigliano†‡ B Maresca§ A Salvatore† M Nino§ G Monfrecola§ F Ayala§ A Carlucci† RC Pugliese§ C Pedone† P Abrescia† 《Journal of the European Academy of Dermatology and Venereology》2008,22(4):417-425
Objective The aim of this work was to assess whether psoriasis is associated with phenotype prevalence and altered activity of haptoglobin (Hpt). Background Hpt is a plasma acute‐phase glycoprotein, displaying in humans three phenotypes. Phenotype prevalence or structure modification of Hpt was associated with several diseases. The Hpt main function is to bind and carry to the liver free haemoglobin for degradation and iron recycling. Hpt was recently found able to bind the apolipoprotein A‐I (ApoA‐I), thus impairing its stimulation on the activity of the enzyme lecithin‐cholesterol acyl‐transferase (LCAT). Study design Hpt was isolated from patients with psoriasis vulgaris, and its activity in haemoglobin or ApoA‐I binding and LCAT inhibition was compared with that of normal protein. Methods Two affinity chromatography steps, the first using resin‐coupled haemoglobin and the second anti‐Hpt antibodies, were used to purify Hpt. The protein phenotype was assessed by electrophoresis. Binding experiments were performed by Enzyme‐linked immunosorbent assay with stationary haemoglobin or ApoA‐I, Hpt in solution and anti‐Hpt antibodies for detection of bound Hpt. Standard LCAT assays were carried out in the presence of Hpt purified from patients or healthy subjects. Results Phenotype prevalence of Hpt in psoriasis was not found. After affinity chromatography by haemoglobin, albumin and ApoA‐I were routinely found heavily contaminating only Hpt from normal subjects. Isolated Hpt from patients had lower activity than normal protein in both haemoglobin binding and LCAT inhibition. Conclusions In psoriasis, Hpt displays some structure modification(s), which might be associated with the protein function in the disease. 相似文献
78.
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography. 相似文献
79.
Osteomyelitis: detection with US 总被引:2,自引:0,他引:2
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis. 相似文献
80.
Growth hormone therapy for protein catabolism 总被引:5,自引:0,他引:5
GH and IGF-I have shown remarkable consistency of effect in a wide range of
catabolic conditions. Doses of around 10 IU/m2/day of GH and 80
micrograms/kg/day of IGF-I over short periods of time can improve net
protein synthesis and preserve lean body mass. Most studies have reported
metabolic endpoints, but favorable clinical effects have included decreased
hospital stay and mortality in burns, improved respiratory muscle function
in COAD, preserved grip strength post- operatively, and improvements in
cardiac and bowel failure. Adverse effects of GH treatment are uncommon and
usually related to glycaemic control. GH and IGF-I have differential
effects on insulin concentrations--increasing or decreasing concentrations,
respectively. The hypoglycaemic effects of IGF-I are dependent on route of
administration and are avoided by subcutaneous delivery. Occasional
patients have needed to discontinue GH treatment due to hyperglycaemia,
although the anabolic action of GH may be partially mediated by increased
insulin levels. The co-administration of GH and IGF-I has theoretical
advantages by both increasing IGF binding-protein concentrations and
balancing glycaemic control. An initial study with combination therapy in
calorically-restricted volunteers has shown anabolic effects greater than
with either agent alone. This approach requires further study in catabolic
patients. There is a need for large, well-designed trials with clinical
rather than purely metabolic end-points, and some of these are already
underway. Should these studies confirm the early findings, financial
considerations will become paramount, although it remains possible that
treatment may be self-financing if lengths of hospital admissions are
shortened.
相似文献