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Platelet count in 38 paired maternal venous and umbilical venous specimens were determined at delivery. Umbilical values were significantly higher than simultaneous maternal values (p = 0.004), and a significant relationship was demonstrated between umbilical values and maternal values (r = 0.54, p = 0.0004). Associations between platelet counts and acid-base variables were found to be insignificant in the mother and the umbilical cord.  相似文献   
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In 13 dogs, experimental obstructive lymphoedema of the lower limb was created by combined radiotherapy and radical groin dissection. Six months later, when the degree of lymphoedema was stable, the lymphatic obstruction was bridged by microvascular insertion of a free omental graft. Six months after grafting, circumferential measurements indicated a statistically significant 38% reduction in the magnitude of lymphoedema. Biopsies showed the omental grafts were alive but contained much fibrous tissue. Lymphatic vessels were identified in 10 of 11 biopsies but connections between these lymphatics and lymphatics proximal to the graft could not be demonstrated by either lymphangiography or dye-injection techniques. The findings indicate that experimental obstructive lymphoedema in the dog can be reduced significantly by insertion of a vascularised omental graft. However, it could not be established that improvement was due to union of graft lymphatics with those of the lymphoedematous limb, although this union may have consisted of lymphatics too small to be demonstrated.  相似文献   
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OBJECTIVE: To analyze the long-term effects of subcranial surgery for anterior skull base tumors on facial growth. STUDY DESIGN AND SETTING: Retrospective study (1994 to 2004) in a university-affiliated hospital. Of 108 patients who underwent a subcranial surgical approach for anterior skull base tumors, six adolescents and five young adults fulfilled study entry criteria for age and follow-up data availability (mean, 3.2 +/- 2 years). Cephalometric x-ray films monitored postoperative facial growth. Anteriorly and posteriorly measured horizontal and vertical maxillary growth were compared with normal values. RESULTS: All subjects had superiorly positioned maxillae (shorter in patients with long-standing pathologies). The upper incisor teeth were proclined relative to the cranial base reference planes. All cephalometric changes were within a 10 percent deviation of normal values. CONCLUSIONS: Subcranial surgery for these tumors minimally affects vertical facial skeleton growth. Early surgery is essential for unaffected horizontal growth. SIGNIFICANCE: Guidelines for anterior skull base tumor surgery in adolescents and young adults.  相似文献   
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Background

Intermittent intravenous dobutamine therapy is used to treat patients with decompensated end-stage chronic heart failure (CHF), in whom the vascular endothelium is usually impaired. Although it has been suggested that modification or reversal of endothelial dysfunction may be of significant therapeutic benefit, the impact of short-term intermittent intravenous dobutamine therapy on flow-mediated dilation (FMD) in patients with severe decompensated end-stage chronic CHF has not been assessed.

Methods

We prospectively assessed the impact of intermittent intravenous low-dose dobutamine therapy on endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin (NTG)-mediated vasodilation using high resolution ultrasound scanning in 20 consecutive male patients with severe CHF and ischemic cardiomyopathy (New York Heart Association functional class IV), at baseline and after 4 months, and compared them to 20 age- and sex-matched control subjects. The cardiac index (CI), stroke index (SI), and systemic vascular resistance (SVR) were assessed non-invasively with a thoracic electrical bioimpedance device before and after intravenous dobutamine therapy.

Results

Intermittent intravenous dobutamine therapy resulted in significant improvement in post-intervention FMD compared with baseline (7.7% ± 2.4% vs 1.1% ± 2.6%; P = .001), a finding not evident in control subjects (1.3% ± 2.6% vs 1.2% ± 2.1%; P = .78). There was no significant effect of dobutamine treatment compared with control subjects on NTG-induced vasodilation (7.6% ± 5.5% vs 7.5% ± 8.8%, P = .979). Short-term dobutamine therapy also significantly improved SVR (1797 ± 926 dyne sec/cm5 vs 2172 ± 1133 dyne sec/cm5, P = .05), CI (2. 4± 0.6 L/min/m2 vs 1.9 ± 0.6 L/min/m2, P = .01), and SI (33.5 ± 11.7 mL/m2 vs 27.2 ± 12.4 mL/m2, P = .02).

Conclusions

Short-term intermittent intravenous low-dose dobutamine therapy significantly improved vascular endothelial function, perhaps demonstrating an additional mechanism for improved SVR, CI, and SI in patients with severe CHF.  相似文献   
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