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11.
Stoll  D; Cines  DB; Aster  RH; Murphy  S 《Blood》1985,65(3):584-588
We studied ten normal subjects and 20 patients with stable, untreated idiopathic thrombocytopenic purpura (ITP) and platelet counts in the range of 35,000 to 110,000/microL. The diagnosis was made by clinical criteria. Platelet-associated IgG was increased in all nine of the nine patients studied. Autologous platelets were labeled with chromium 51 and reinfused for measurement of mean cell life and platelet production rate. Mean cell life was calculated by two methods, weighted mean and multiple hit, with excellent agreement between the two. As expected, mean cell life was significantly reduced in ITP patients as compared to the normal subjects (2.9 days v. 8.0 days, P less than .001). However, mean platelet production rates in ITP patients and normal subjects, 3.5 and 3.8 X 10(9) platelets/k/d respectively, were not significantly different. Platelet production rate was above and below the normal range (2 to 5.6 X 10(9) platelets/k/d) in two and four patients, respectively. We conclude that the rate of platelet production is not increased in most patients with ITP who have platelet counts greater than 35,000/microL. We did find that platelet size was increased in eight of the 12 patients in whom it was measured, including two of the patients with low platelet production.  相似文献   
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BackgroundDespite increasing awareness within the medical community about the benefits of bariatric surgery for type 2 diabetes mellitus (T2DM), little is known about patients’ attitudes toward bariatric surgery as a treatment for T2DM. The objective of this study was to investigate the attitudes of individuals with T2DM and a body mass index of 30 to 40 kg/m2 concerning bariatric surgery for the treatment of T2DM.MethodsPatients identified from the Pennsylvania Integrated Clinical and Administrative Research Database (PICARD) were surveyed about perceptions of the safety profile and efficacy of bariatric surgery as a treatment for obesity and T2DM and their willingness to be randomly assigned to receive a surgical procedure.ResultsA total of 130 individuals of 513 (25.3%) responded. Respondents had a median (interquartile range) age of 58.0 (range 51.0–63.0) years and self-reported body mass index of 32.9 (range 30.9–35.2) kg/m2. Roughly half (66 of 130) were female. Overall, only 20.3% of respondents had positive views of bariatric surgery, with few reporting that it is a safe (14.3%) and effective (28.5%) treatment for T2DM. Less than 20% of respondents were willing to be randomly assigned to undergo a surgical procedure for the treatment of diabetes (16.1%) or obesity (17.5%).ConclusionsFew obese individuals with T2DM who responded to the survey had positive views about bariatric surgery. Patients’ concerns about the procedure’s safety profile and efficacy must be addressed to improve the acceptability of bariatric surgery as well as the feasibility of randomized, controlled trials of bariatric surgery for these individuals.  相似文献   
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The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone.  相似文献   
15.
目的:评估人工流产(指手术流产)对乳腺癌危险性的可能影响。方法:研究在上海267040例妇女的一项乳房自我检查随机试验的队列人群中进行,由队列研究和巢式病例对照研究两部分组成。结果:依据基线调查表采集的资料分析,人工流产不增加乳腺癌危险性。调整潜在的混淆因素后,OR=1.06(95%CI:0.91~1.25)。人工流产次数增加无危险性趋势增加。从更详细的652例乳腺癌病例和694例对照资料分析,得出相似的结果。人工流产发生在首次生育后不增加危险性;少数妇女在首次生育前人工流产以及妊娠13周后人工流产,虽然被观察到危险性有增加,但无显著性统计学意义。结论:在中国,人工流产不是乳腺癌发生的重要原因。  相似文献   
16.
[目的]调查产后抑郁症患者的现状及需求,探讨预防措施。[方法]定性与定量研究相结合,定性采用专题小组讨论和半结构性访谈,12人参加专题讨论、9人半结构性访谈;定量研究随机抽取本市各社区产后42d的产妇776例行问卷调查。[结果]产妇月子期间常发生头疼、恶心、焦虑、恐惧、失眠以及照顾新生儿困难;半结构性访谈中有1产妇处于产后抑郁症的临界,EPDS量表测定为12分;776例产妇月子里有身心健康问题者692例,求助者91.0%,其中需要社区护理人员帮助的71.7%,实际寻求帮助仅12.7%。[结论]预防产后抑郁症应实行社区医护人员培训与产后访视人员的准入制度,采取社区医护干预的三级预防,同时拓展社区产后保健服务的内涵。  相似文献   
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18.
1. 5-Hydroxytryptamine (5-HT) exerts both contractile and relaxant effects in the marmoset isolated aorta, actions that are unaffected by the 5-HT2 antagonist ketanserin. The aim of the present study was to define the receptors mediating the contractile activity of 5-HT in the marmoset aorta.
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A2 agonist U44069 in order to amplify the responses; or (ii) exposed to N ω-nitro- L -arginine (100 μmol/L) plus LY 53857 (0.1 μmol/L; a 5-HT2 receptor antagonist shown previously to inhibit relaxation). The effect of 5-HT on adenosine 3',5'-cyclic monophosphate (cAMP) formation was also investigated.
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT1D antagonist GR 127935; (iii) a contractile response to methysergide; (iv) a lack of effect of tropisetron, an antagonist of 5-HT3 and 5-HT4 receptors; and (v) inhibition of forskolin-stimulated cAMP formation by 5-HT (in the presence of LY 53857), indicative of negative coupling to adenylate cyclase.
4. The above effects fulfil the criteria for a 5-HT1-like receptor. In view of the previous finding that this contractile response is insensitive to ketanserin, it is concluded that the contractile effects of 5-HT in the marmoset aorta are mediated exclusively by a 5-HT1-like receptor.  相似文献   
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BACKGROUND: Some investigators fear that dieting may precipitate binge eating and other adverse behavioral consequences. OBJECTIVE: The objective of the study was to examine whether dieting would elicit binge eating and mood disturbance in individuals free of these complications before treatment. DESIGN: A total of 123 obese women were randomly assigned to 1) a 1000 kcal/d diet that included 4 servings/d of a liquid meal replacement (MR); 2) a 1200-1500 kcal/d balanced deficit diet (BDD) of conventional foods; or 3) a nondieting (ND) approach that discouraged energy restriction. All women attended weekly group sessions for 20 wk and biweekly sessions from week 20 to week 40. RESULTS: At week 20, participants in the MR, BDD, and ND groups lost 12.1 +/- 6.7%, 7.8 +/- 6.0%, and 0.1 +/- 2.4% of initial weight, respectively (P < 0.001). During the first 20 wk, there were no significant differences among groups in the number of persons who had objective binge episodes or in reports of hunger or dietary disinhibition. Symptoms of depression decreased significantly more (P < 0.001) in the MR and BDD groups than in ND participants. At week 28, significantly more (P < 0.003) cases of binge eating were observed in MR participants than in the 2 other groups. No differences, however, were observed between groups at weeks 40 or 65 (a follow-up visit). At no time did any participant meet criteria for binge-eating disorder. CONCLUSION: Concerns about possible adverse behavioral consequences of dieting should not dissuade primary care providers from recommending modest energy restriction to obese individuals.  相似文献   
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