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51.
DH Rushton PhD 《International journal of clinical practice》1999,53(1):50-53
While the precise incidence of androgenetic alopecia is unknown, it is universally acknowledged to be the most common hair problem in men. Balding is generally associated with ageing; consequently, the desire to prolong a youthful appearance inevitably leads to demands for effective treatments. Further, changing attitudes in modern society have resulted in people becoming concerned about their appearance and less tolerant about conditions that might be alleviated by medical intervention. The importance of hair loss upon quality of life has been underestimated by the medical profession. Clinicians failing to accept hair loss as an important medical problem ignore the real distress suffered by a significant proportion of those affected. New options for treatment that selectively target the metabolic pathways involved in the balding process are showing promise. The first generation of such drugs, Propecia, is now available in some countries and other molecules are currently under development. 相似文献
52.
Summary
This study examined the effects of quercetin on spontaneously contracting portal veins isolated from healthy young adult male and female Wistar rats (250–300 g). Quercetin (10-7–10-4 M) always produced significant biphasic effects, comprising an initial brief stimulant effect (rise in basal tone), followed by a sustained, longer-lasting secondary relaxant (inhibitory) effect on the venous tissues. The initial brief contractions of the venous muscle preparations were not modified by preincubation of the tissues with prazosin (10-6 M), suggesting that the initial upsurge in basal tone and increases in contractile frequencies of the venous tissues were probably not mediated via alpha1-adrenoceptor stimulation. However, preincubation of the tissues with nifedipine (10-7 M) significantly suppressed (p < 0.05) or attenuated the initial stimulant effect of quercetin, suggesting that the flavonoid might be activating L-type voltage-dependent calcium channels. The vasorelaxant effect of quercetin was partially but not significantly (p > 0.05) inhibited by L-NAME (100 μM) or indomethacin (10 μM), suggesting that the vasorelaxant effect of the flavonoid was unlikely to be mediated via endothelium-dependent relaxing factor (EDRF), or through prostacyclin (PGI2) pathways. N-p-tosyl-l-phenylalanine-chloromethyl-ketone (TPCK, 3 μM) significantly (p < 0.01) antagonised quercetin-induced relaxations, suggesting that cAMP-dependent protein kinases might have contributed, at least in part, towards the vasorelaxant effect of quercetin on rat isolated portal veins. 相似文献53.
54.
Gazitt Y; Reading CC; Hoffman R; Wickrema A; Vesole DH; Jagannath S; Condino J; Lee B; Barlogie B; Tricot G 《Blood》1995,86(1):381-389
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly. 相似文献
55.
Bérubé-Parent S Prud'homme D St-Pierre S Doucet E Tremblay A 《International journal of obesity (2005)》2001,25(8):1144-1153
OBJECTIVE:: Sibutramine favors a negative energy balance and also has the potential to increase heart rate and blood pressure. We investigated if a progressive supervised sibutramine--diet--exercise clinical intervention could increase the body weight loss previously reported while minimizing the potential cardiostimulatory effects of this drug. DESIGN AND SUBJECTS:: The tri-therapy intervention was divided into two phases of 6 weeks each in which sibutramine (10 mg) was taken once daily by eight obese men (body mass index (BMI) between 30 and 40 kg/m(2)). Part A consisted of a dietary follow-up with an energy restriction, whereas in part B an aerobic exercise program combined with a low-fat diet was introduced. Systolic (SBP) and diastolic (DBP) blood pressure, resting heart rate (RHR) and body weight were measured every 2 weeks while body density, resting metabolic rate (RMR) and respiratory quotient (RQ) were determined before and after the intervention. RESULTS:: This clinical intervention produced a substantial body weight loss (-10.7 kg, P<0.01) which was about twice as much as other 12-week studies. In part A, both RHR (+4 beats/min) and DBP (+5 mmHg, P<0.01) were increased. However, after part B, RHR (-8 beats/min, P=0.02) and DBP (-3 mmHg, P<0.01) were significantly decreased. RMR was decreased at the end of the program but this effect did not persist after adjustments for fat-free mass. RQ was also reduced (-0.05, P<0.01) following the clinical tri-therapy. CONCLUSION:: In conclusion, these observations suggest that this clinical tri-therapy favored a satisfactory benefit--risk profile since it enhanced weight loss without inducing increases in heart rate and blood pressure or detrimental changes in RMR and substrate oxidation. 相似文献
56.
St-Pierre J Lemieux I Perron P Brisson D Santuré M Vohl MC Després JP Gaudet D 《The American journal of cardiology》2007,99(3):369-373
This study tested the hypothesis that the "hypertriglyceridemic waist" phenotype (waist girth >90 cm [35.4 inches] in men and >85 cm [33.5 inches] in women, along with a plasma triglyceride concentration of >or=2.0 mmol/L [177 mg/dl]) as a covariate of metabolic syndrome features (hyperinsulinemia, hyperapolipoprotein B, and small low-density lipoprotein particles), is predictive of premature coronary artery disease (CAD) among patients with glucose intolerance or type 2 diabetes. Glucose intolerance and type 2 diabetes were assessed after an oral glucose tolerance test among 1,190 men and women using the American Diabetes Association criteria. Glycemic control was evaluated using hemoglobin A1c levels. CAD was considered present on the basis of a clinical history of retrosternal pains on exertion, electrophysiologically and clinically documented myocardial infarction, or angiographic evidence of coronary lesions. More than 53% of men (n = 103) with a waist circumference >or=90 cm (35.4 inches) and nearly 80% of women (n = 122) with a waist circumference >or=85 cm (33.5 in.) with triglyceride levels >or=2 mmol/L (177 mg/dl) were diagnosed with glucose intolerance or type 2 diabetes. Survival models revealed that those with glucose intolerance or type 2 diabetes with the "hypertriglyceridemic waist" phenotype experienced their first CAD symptoms 5 years earlier than those without this phenotype. This elevated and earlier risk of CAD was statistically significant (hazard ratio 2.0, 95% confidence interval 1.2 to 3.7, p = 0.02). In conclusion, the "hypertriglyceridemic waist" phenotype, an inexpensive and simple tool identifying subjects with metabolic syndrome features, is a significant marker of CAD manifestations occurring at an earlier age in those with glucose intolerance or type 2 diabetes. 相似文献
57.
Chalmers RM; Howard RS; Wiles CM; Hirsch NP; Miller DH; Williams A; Spencer GT 《QJM : monthly journal of the Association of Physicians》1996,89(6):469-476
Twenty-nine patients with a neuronopathic or neuropathic disorder were
referred for assessment of respiratory insufficiency between 1978 and 1994.
Diagnoses included spinal muscular atrophy (6), chronic idiopathic
demyelinating neuropathy (4), Vialetto-van Laere syndrome (3), hereditary
motor and sensory neuropathy (3) and a miscellaneous group (5). We also
describe seven patients with Guillain-Barre syndrome (GBS) who required
long-term ventilatory support for over 6 months to 7 years after the
initial illness. Respiratory insufficiency occurred as a consequence of
respiratory muscle weakness, impaired bulbar function and restrictive lung
defects. In some groups presentation was with progressive nocturnal
hypoventilation culminating in acute respiratory failure. Five patients
with GBS or chronic idiopathic demyelinating neuropathy were weaned from
ventilatory support up to 18 months after the initial illness. The
remaining 24 patients required continuous or nocturnal ventilatory support
using intermittent positive-pressure ventilation (13), negative pressure
ventilation (4), nasal-mask-delivered intermittent positive-pressure
ventilation (4), nasal-mask-delivered continuous positive-pressure
ventilation (3), mouthpiece-assisted ventilation by day (2) and rocking bed
(1). None have been weaned from support after a period of ventilation
ranging from one month to 10 years. Eight patients have subsequently died.
相似文献
58.
Kirsten JE Asmus-Szepesi Paul L de Vreede Anna P Nieboer Jeroen DH van Wijngaarden Ton JEM Bakker Ewout W Steyerberg Johan P Mackenbach 《BMC geriatrics》2011,11(1):1-17
Background
Elderly persons admitted to the hospital are at risk for hospital related functional loss. This evaluation aims to compare the effects of different levels of (integrated) health intervention care programs on preventing hospital related functional loss among elderly patients by comparing a new intervention program to two usual care programs.Methods/Design
This study will include an effect, process and cost evaluation using a mixed methods design of quantitative and qualitative methods. Three hospitals in the Netherlands with different levels of integrated geriatric health care will be evaluated using a quasi-experimental study design. Data collection on outcomes will take place through a prospective cohort study, which will incorporate a nested randomised controlled trial to evaluate the effects of a stay at the centre for prevention and reactivation for patients with complex problems. The study population will consist of elderly persons (65 years or older) at risk for functional loss who are admitted to one of the three hospitals. Data is prospectively collected at time of hospital admission (T0), three months (T1), and twelve months (T2) after hospital admission. Patient and informal caregiver outcomes (e.g. health related quality of life, activities of daily living, burden of care, (re-) admission in hospital or nursing homes, mortality) as well as process measures (e.g. the cooperation and collaboration of multidisciplinary teams, patient and informal caregiver satisfaction with care) will be measured. A qualitative analysis will determine the fidelity of intervention implementation as well as provide further context and explanation for quantitative outcomes. Finally, costs will be determined from a societal viewpoint to allow for cost effectiveness calculations.Discussion
It is anticipated that higher levels of integrated hospital health care for at risk elderly will result in prevention of loss of functioning and loss of quality of life after hospital discharge as well as in lower burden of care and higher quality of life for informal caregivers. Ultimately, the results of this study may contribute to the implementation of a national integrated health care program to prevent hospital related functional loss among elderly patients.Trial registration
The Netherlands National Trial Register: NTR2317 相似文献59.
In clonogenic assays of hematopoietic progenitors, high concentrations (4 U/mL) of erythropoietin (epo) reduced the formation of granulocyte- macrophage (GM) colonies and diminished the number of granulocytes formed per culture plate. Fetal progenitors were more sensitive to these effects of epo than were progenitors from adults, displaying these reductions at greater than or equal to 1 U epo/mL. The mechanism was investigated by growing fetal progenitors stimulated by recombinant GM-CSF, in the absence of epo, and when eight-cell clones first appeared, mapping their location, then adding epo, and assessing its effect on the subsequent differentiation of the clones. In the absence of epo, the clones developed exclusively into GM colonies. However, if developing clones were presented with epo, 85% matured into GM colonies, but 15% became multilineage or normoblast colonies. In addition, developing clones that were presented with epo produced colonies that contained fewer neutrophils. These effects of epo on neutrophil generation were observed with each of three varieties of recombinant epo, and also with purified human epo, but were not observed using epo that had been neutralized with rabbit anti-epo antiserum. 相似文献
60.
Karelis AD St-Pierre DH Conus F Rabasa-Lhoret R Poehlman ET 《The Journal of clinical endocrinology and metabolism》2004,89(6):2569-2575
Obesity is thought to be a heterogeneous disorder with several possible etiologies; therefore, by examining subtypes of obesity we attempt to understand obesity's heterogeneous nature. The purpose of this review was to investigate the roles of metabolic, body composition, and cardiovascular disease risk in subtypes of obesity. We briefly consider two subtypes of obesity that have been identified in the literature. One subset of individuals, termed the metabolically healthy, but obese (MHO), despite having large amounts of fat mass compared with at risk obese individuals shows a normal metabolic profile, but remarkably normal to high levels of insulin sensitivity. Preliminary evidence suggests that this could be due at least in part to lower visceral fat levels and earlier onset of obesity. A second subset, termed the metabolically obese, but normal weight (MONW), present with normal body mass index, but have significant risk factors for diabetes, metabolic syndrome, and cardiovascular disease, which could be due to higher fat mass and plasma triglycerides as well as higher visceral fat and liver content. We also briefly consider the potential role of adipose and gastrointestinal hormonal profiles in MHO and MONW individuals, which could lead to a better understanding of potential factors that may regulate their body composition. This information will eventually be invaluable in helping us understand factors that predispose to or protect obese individuals from metabolic and cardiovascular disease. Collectively, a greater understanding of the MHO and MONW individual has important implications for therapeutic decision making, the characterization of subjects in research protocols, and medical education. 相似文献