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141.
Evidence of disseminated intravascular coagulation was recorded in eight patients with toxic epidermal necrolysis (TEN)--Lyell's syndrome. Patients were treated with low doses of heparin in combination with the usual treatment of TEN, i.e. maintenance of fluid and electrolyte balance, systemic corticosteroids, antibiotics and aseptic dressings, in the Intensive Care Unit environment. It is suggested that the alteration of haemostasis and inter-related biological systems, such as activation of components of complement, kinins and immunoglobulins, may affect the outcome of TEN.  相似文献   
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The association between polycystic ovary syndrome (PCOS) and recurrent miscarriage (RM) has been long established, but the relative importance of this condition as a cause of RM is far from clear. Previous studies on the prevalence of PCOS in RM have been hampered by a lack of objective and universally accepted criteria for the diagnosis of PCOS, resulting in considerable controversy. However, the Rotterdam criteria have since been accepted as the gold standard for diagnosis of PCOS, and therefore these criteria have been used to produce a much clearer and more objective assessment of the prevalence of PCOS in RM. Three hundred women with recurrent miscarriage were studied. A diagnosis of PCOS was established via measurement of cycle length and day 21 serum progesterone, determination of the free androgen index and pelvic ultrasonography. All ultrasound reports prior to publication of the Rotterdam criteria were reviewed, ensuring consistency in the diagnosis of a polycystic ovary. Ultrasound scans of 27 patients confirmed polycystic ovaries with a further 10 scans suggestive of polycystic ovaries, but with insufficient information for the Rotterdam criteria to be applied. Hence, 27–37 (9.0–12%) patients presented with ultrasonographic polycystic ovaries. Using the Rotterdam criteria, 25–30 (8.3–10%) patients had PCOS. It is concluded that the prevalence of PCOS in RM is considerably lower than has previously been accepted.  相似文献   
145.
Adrenomedullin (ADM) is closely related to calcitonin gene-related peptide, which has a known causative role in migraine. Animal studies have strongly suggested that ADM has a vasodilatory effect within the cerebral circulation. For these reasons, ADM is also likely to be involved in migraine. However, the hypothetical migraine-inducing property and effect on human cerebral circulation of ADM have not previously been investigated. Human ADM (0.08 µg kg−1 min−1) or placebo (saline 0.9%) was administered as a 20-min intravenous infusion to 12 patients suffering from migraine without aura in a crossover double-blind study. The occurrence of headache and associated symptoms were registered regularly 24 h post infusion. Cerebral blood flow (CBF) was measured by 133Xenon single-photon emission computed tomography, mean blood flow velocity in the middle cerebral artery (VMCA) by transcranial Doppler and the diameter of peripheral arteries by transdermal ultrasound (C-scan). ADM did not induce significantly more headache or migraine compared with placebo ( P  = 0.58). CBF was unaffected by ADM infusion (global CBF, P  = 0.32 and rCBFMCA, P  = 0.38) and the same applied for the VMCA ( P  = 0.18). The superficial temporal artery dilated compared with placebo ( P  < 0.001), and facial flushing was seen after ADM administration ( P  = 0.001). In conclusion, intravenous ADM is not a mediator of migraine headache and does not dilate intracranial arteries.  相似文献   
146.
Background: Left atrial (LA) endocardial voltage characteristics assessed during atrial fibrillation (AF) have not been previously compared in different AF types. This study was aimed at investigating the LA voltages and volumes in patients with paroxysmal and persistent AF. Methods: LA electroanatomic voltage maps acquired during AF were compared between consecutive patients without major structural heart disease undergoing first catheter ablation for paroxysmal AF (n = 100) or persistent AF (n = 100). The groups were comparable in baseline clinical characteristics. Results: Patients with persistent AF presented with lower median LA voltage (median 0.41, interquartile range [IQR] 0.31–0.51 mV versus median 0.99, IQR 0.47–1.56 mV; P < 0.001), and maximum LA voltage (4.07 ± 1.76 vs 6.42 ± 2.16 mV; P < 0.001). They also had a higher proportion of the LA points exhibiting voltage <0.2 mV (30 ± 20 vs 12 ± 11%; P < 0.001) and voltage 0.2–1.0 mV (55 ± 15 vs 42 ± 19%; P < 0.001). They further displayed higher LA volume/body surface area (75 ± 16 vs 58 ± 13 mL/m2; P < 0.001). In the multivariate regression model, both LA voltage (P < 10?9) and LA volume (P < 10?5) were significant determinants of AF type. Conclusion: Patients with persistent AF had significantly lower LA voltage compared with patients with paroxysmal AF even after adjustment for differences in indexed LA volume. LA voltage represents an independent covariate of clinical manifestation of AF. (PACE 2010; 541–548)  相似文献   
147.
Background Though the use of median stermotomy has been fairly standardized for the approach to the heart and great vessels, since the advent of cosmetically appealing incisions, thoracotomy has come to be a justifiable alternative incision. This paper presents our experience with this approach and the advantages over the conventional approach as well as over other incisions for the correction of intra-cardiac anomalies. Methods 93 patients underwent open cardiac procedures using the posterior thoracotomy approach since June 1997 to December 2000. There were 69 patients with ostium secundum atrial septal defects and 12 patients with sinus venous defects. Other anomalies included perimembranous ventricular septal defects in 3 patients, partial atrioventricular septal defects in 3 patients and transitional atrioventricular septal defects in 2 patients. Besides these, one patient each underwent atrial septectomy with right modified Blaloc—Taussing shunt and correction of hemianomalous pulmonary venous connection with intact atrial septum using this approach. The median age of the patients was 8 years with a range of 10 months to 41 years. 10 patients were males. Results The median operation time (skin to skin) was 236 minutes. Median bypass times and aortic cross clamp times were 63 minutes and 31.5 minutes respectively. The median ICU stay was 25.2 hours. There were no significant immediate post operative complications requiring intervention in any patient. The mean chest drainage was 80 ml per 24 hours. One patient had a superficial wound dehiscence which healed with daily dressings One patient had atelectasis of the right upper lobe which recovered with chest physiotherapy. All patients are on regular follow up to assess the status of their scars. One patients developed a mass on the right atrial free wall following closure of atrial septal defect one year earlier and the underwent reoperation for removal of the mass. Patients on follow up were interrogated and all were satisfied with the cosmesis of their scars. None of the patients had any physical disability due to their scars. Conclusions The limited posterior thoracotomy incision offers a cosmetically attractive approach to the heart in selected patients. The approach is easy and the techniques reproducible. The technique carries with it no additional risk and has the advantage of not interfering with future development of the breast in young pre pubertal girls.  相似文献   
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目的:验证二甲双胍治疗抗精神病药引起的血脂异常的疗效和安全性。方法:将两项随机、安慰剂的 对照研究纳入分析。共有201例服用抗精神病药物后出现血脂异常的首发精神分裂症患者,并将其分为1 000 mg/d 二甲双胍组(以下简称为二甲双胍组,n=103)和安慰剂组(n=98),观察24周。在基线、治疗后第12周和第24周进行 临床症状及体重、血糖、血脂等代谢指标的评估。结果:二甲双胍治疗后,二甲双胍组和安慰剂组之间低密度脂 蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的平均差异从基线时的0.16 mmol/L,降低到第24周结束时的 –0.86 mmol/L,降低了1.02 mmol/L,差异有统计学意义(P<0.01)。而24周结束时,二甲双胍组LDL-C≥3.37 mmol/L的 患者有25.3%,显著低于安慰剂组24周结束时的64.8%(P<0.01)。与安慰剂组相比,二甲双胍组的体重、体重指数、 胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油和高密度脂蛋白胆固醇也有显著变化,差异均有统计学意义(均 P<0.05)。治疗对体重和胰岛素抵抗的影响出现在第12周,并且在第24周进一步改善,但对改善血脂异常的作用在第 24周结束时才出现。结论:二甲双胍治疗对于改善抗精神病药物引起的血脂异常和胰岛素抵抗是有效的,并且改善 抗精神病药物诱导的胰岛素抵抗出现的时间早于降低血脂异常的时间。  相似文献   
150.
A novel system to study the effects of co-cross-linking CD23/FceRII and sIg on murine B lymphocytes utilizes a highly multivalent form of anti- Ig prepared by covalently linking anti-Ig antibodies to a DNP-dextran backbone. CD23-sIg co-cross-linking is accomplished by the addition of DNP-specific monoclonal IgE. Previous studies demonstrated that co- cross-linking CD23 and sIg significantly inhibited mouse B cell proliferation, especially at high doses of the multivalent anti-Ig. Interestingly, examination of early activation signals reveals no difference in B cells subjected to co-cross-linking conditions as compared to B cells activated with anti-Ig alone. Total cellular protein tyrosine phosphorylation levels are unchanged by co-cross- linking. Analysis of B cell mRNA reveals that co-cross-linking the receptors does not alter the expression levels of ornithine decarboxylase 8 h after stimulation as compared to the controls. In contrast, levels of the proto-oncogene c-myc were significantly elevated 1 h after inducing B cell activation under co-cross-linking conditions. However, it remains unclear whether this aberrant c-myc regulation plays any role in inducing apoptosis. In addition, on day 3 after stimulation, the co-cross-linking of CD23 and sIg resulted in the formation of apoptotic B cells, determined by both photomicroscopy of the B cell cultures and FACS analysis of B cell nuclei. B cells obtained from bcl-2 transgenic mice proliferated as well as controls, and failed to undergo apoptosis when CD23 and sIg were co-cross-linked on their surface. These studies indicate that co-cross-linking of CD23 with B cell sIg inhibits B cell proliferation by a mechanism that is distinct from that seen by co-cross-linking of the Fc gamma RII and sIg. In addition, these results suggest a means by which antigen- specific IgE can down-regulate additional B cell activation and IgE synthesis.   相似文献   
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