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11.
程富礼  贾志良 《医学争鸣》2005,26(16):1471-1471
1临床资料1997-10/2003-5采用Ilizarov外固定器结合足部小手术矫正足部畸形12例(12足),男9例,女3例,年龄3.3~9.2岁,平均5.5岁.其中先天性者8例(均为僵硬型,其他手术方法治疗后复发),神经源性3例(系脑脊膜膨出引起),外伤性者1例(烧伤引起).手术前根据患儿年龄、患足畸形程度、大小及X线片形态结构特点,选择合适的Ilizarov外固定器.  相似文献   
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Kretzer RM  Burger PC  Tamargo RJ 《Neurosurgery》2004,54(2):515-8; discussion 518-9
OBJECTIVE AND IMPORTANCE: Hypertrophic neuropathy of the cauda equina (HNCE) is a rare form of peripheral neuropathy. The diagnosis is complicated by an insidious clinical presentation and complex radiographic images. We present a case of HNCE caused by chronic inflammatory demyelinating polyneuropathy with symptomatic improvement after decompressive lumbar laminectomy and dural expansion. CLINICAL PRESENTATION: A 54-year-old woman with a history of back pain since she was in her 20s presented with low back and radicular pain that had increased during a period of 6 months, bilateral lower-extremity weakness, and sensory loss in the right thigh. Magnetic resonance imaging of the lumbosacral spine revealed multiple, poorly enhancing mass lesions and apparent intrathecal nerve root thickening from L1 to L5. INTERVENTION: An L1-L5 decompressive laminectomy, performed with continuous somatosensory evoked potential and electromyographic monitoring, revealed multiple segmentally enlarged nerve roots. One nerve root that did not respond to high levels of stimulation was identified. This root was resected and submitted for pathological analysis. The dura was expanded with an 11-cm-long dural patch. The pathological examination revealed hypertrophic neuropathy, with extensive S-100-positive "onion bulb" formation. The patient's symptoms improved postoperatively. CONCLUSION: HNCE is a rare disorder that can cause radicular pain and lower-extremity weakness, sensory loss, and hyporeflexia. One possible cause is demyelinating polyneuropathy. Although medical management is typically effective in the treatment of demyelinating polyneuropathy, it has little effect on compressive symptoms caused by intradural nerve root enlargement. As this case demonstrates, surgical management of symptomatic radiculopathy by lumbar laminectomy is a reasonable and effective approach to the treatment of HNCE.  相似文献   
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Dorcas Hager Padget was a pioneer in the fields of neurosurgical illustration and neuroembryology who practiced during the early 20th century at The Johns Hopkins University. Without a college degree, she trained as a medical illustrator in the Johns Hopkins School of Medicine's Department of Art as Applied to Medicine under Max Br?del. She began her career working for Walter Dandy as his medical artist, gaining worldwide recognition for her neurosurgical illustrations. With Dandy's encouragement, Hager Padget undertook her own scientific research, studying neurodevelopment and aneurysm formation in the circle of Willis by using human embryos from the world-renowned Carnegie Collection. She made lasting contributions to the field of neuroembryology, publishing the first major work on neurodevelopment of the cerebral arterial and venous systems. Following Dandy's death in 1946, Hager Padget began a full-time career as a scientific researcher, first at the Department of Embryology at the Carnegie Institution of Washington in Baltimore and later at the University of Maryland School of Medicine. She continued to make contributions to the field of congenital malformations of the brain and spine, coining the term "neuroschisis" to describe a possible mechanism of neural tube damage leading to the creation of a myelomeningocele. The authors describe Dorcas Hager Padget's contributions to neurosurgical illustration and neuroembryology, as well as her remarkable career.  相似文献   
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BACKGROUND: Isotretinoin is a known teratogen, and when it is prescribed to women of childbearing potential, 2 forms of contraception must be used, commonly including hormonal contraception. Although isotretinoin and estradiol are metabolized largely by cytochrome P450 (CYP) 3A4 and glucuronidation, the potential for clinical drug interaction, with subsequent pharmacodynamic impact, has not been evaluated. METHODS: We enrolled 26 healthy women who were to receive isotretinoin for the treatment of severe, recalcitrant nodular acne and who were taking or planning to take oral contraceptives. The pharmacokinetics of ethinyl estradiol and norethindrone (INN, norethisterone) (the components of Ortho Novum 7/7/7; Ortho-McNeil Pharmaceutical, Inc, Raritan, NJ) and pharmacodynamic assessments of oral contraceptive effectiveness (concentrations of serum progesterone, luteinizing hormone, and follicle-stimulating hormone) were determined on days 6 and 20 of 2 separate oral contraceptive cycles, before and during isotretinoin treatment. RESULTS: The addition of isotretinoin to the oral contraceptive regimen resulted in small and inconsistent, although statistically significant (P <.04), decreases in the concentrations of both ethinyl estradiol (9% decrease in area under the plasma concentration-time curve from time 0 to 24 hours after the dose on day 6) and norethindrone (11% decrease in maximum plasma concentration on day 20). Isotretinoin did not cause any statistically significant increases in pharmacodynamic markers, although a majority of women had increases in these measures. Although there was no correlation between isotretinoin (or metabolite) levels and oral contraceptive levels (P >.05), there was a correlation between progesterone level and oral contraceptive levels (P <.05). Variability was large for both pharmacokinetic measures (median coefficients of variation of 44%-69% [for each time point within a study period]) and pharmacodynamic measures (median coefficients of variation of 64%-114%). One woman in each study phase, one before and one during isotretinoin treatment, had a progesterone elevation consistent with possible ovulation. No serious or unexpected adverse events were observed. CONCLUSIONS: The small reduction in ethinyl estradiol and norethindrone levels associated with isotretinoin was not associated with any pharmacodynamic changes in our study. The combination of the teratogenic risk of isotretinoin and the large variability of and correlation between oral contraceptive levels and pharmacodynamic measures, however, strongly reinforces the necessity of additional contraceptive methods during concomitant administration of these drugs.  相似文献   
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Dipeptidyl peptidase IV (DPPIV) is a transmembrane serine protease which is involved in the process of tumor invasion and development of metastases in human cancers. The aim of this study was to investigate the expression of DPPIV in cancer and stromal cells of both esophageal adenocarcinoma and squamous cell carcinoma (SCC). Tissue material from 159 patients was analyzed using immunohistochemistry. Western blotting was performed on cell lines and fresh frozen tissue sections. Results were compared with clinicopathological features. Evaluation of the immunohistochemical findings revealed significant differences between DPPIV expression in carcinoma cells and stromal cells, depending on the histological tumor type. A significantly higher level of DPPIV was found in adenocarcinomas compared to SCCs while no DPPIV was detected in normal esophageal epithelium. Overexpression of DPPIV in patients with adenocarcinoma was additionally associated with distant metastases. Thus, differences of DPPIV level in esophageal carcinomas compared with normal epithelium showed that esophageal malignancies were associated with an increased amount of cell surface‐bound DPPIV. Radiotherapy in patients had no impact on DPPIV expression in analyzed tissue samples. There was no correlation between DPPIV expression in cancer or stromal cells and survival of the patients.  相似文献   
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Four hours of complete normothermic ischemia in the rat hindlimb has been thought to produce extensive and irreversible damage and no possibility of salvage by reperfusion. This study tests the hypothesis that, in contrast to conventional wisdom, the cellular integrity is preserved after 4 hours of complete warm ischemia and control of the initial reperfusion can restore immediate contractility in these limbs. Ninety-two rat hindlimbs were isolated and 26 of the 92 did not undergo ischemia or reperfusion and served as controls. Sixty-six limbs were subjected to 4 hours of complete warm ischemia; of those 34 were assessed after the ischemic period without reperfusion and 32 were reperfused after the ischemic period. Nineteen hindlimbs were reperfused with Krebs-Henseleit buffer at a pressure of 100 mmHg to simulate embolectomy (uncontrolled reperfusion). In 13 legs a modified reperfusate at a pressure of 60 mmHg was used during the initial 30 minutes followed by an additional 30 minutes of reperfusion with 100 mmHg using Krebs-Henseleit buffer (controlled reperfusion). At the end of each experimental protocol, limbs were assessed by the following methods: muscle contraction, water content, volume, high energy phosphate content, muscle pH, effluent pH, mitochondrial function, ultrastructure, flow, and creatinkinase activity in the effluent. Data are expressed as mean +/- SEM. Significant differences were defined as probabilities for each test of p less than 0.05. Four hours of complete warm ischemia resulted in a severe reduction of adenosine triphosphate (4.0 +/- 0.8 vs 27.1 +/- 6.7 mumol/gm protein, p less than 0.001) and no contractions could be stimulated (0.0 +/- 0.0% CC). Muscle pH fell to 6.3 +/- 0.1 (p less than 0.001), and ultrastructural damage occurred (score 3.3 +/- 0.4 vs 0.8 +/- 0.1, p less than 0.002). However, there was only a slight increase in water content of the soleus muscle (78.7 +/- 0.2% vs 74.8 +/- 1.1%, p less than 0.05) without increase in limb volume (103.6 +/- 0.6% CV). In addition mitochondrial function was preserved well: mitochondrial oxidative phosphorylation capacity remained at 94% of control levels, ST3 at 93%, and ADP/O at 100% of control. Most importantly, controlled reperfusion restored immediate contractility in all limbs and was superior in all parameters investigated compared to uncontrolled reperfusion. These data support our inference that necrosis of skeletal muscle does not invariably occur after four hours of complete warm ischemia and suggest that muscle salvage by controlled reperfusion is possible after at least 4 hours of warm ischemia.  相似文献   
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Changes in heart transplantation (HT) donor and recipient demographics may influence the incidence of primary graft dysfunction (PGD). We conducted a retrospective study to evaluate PGD incidence, trends, and associated risk factors by analyzing consecutive adult patients who underwent HT between January 2009 and December 2014 at our institution. Patients were categorized as having PGD using the International Society for Heart & Lung Transplantation (ISHLT)–defined criteria. Variables, including clinical and demographic characteristics of donors and recipients, were selected to assess their independent association with PGD. A time‐trend analysis was performed over the study period. Three‐hundred seventeen patients met inclusion criteria. Left ventricular PGD, right ventricular PGD, or both, were observed in 99 patients (31%). Risk factors independently associated with PGD included ischemic time, recipient African American race, and recipient amiodarone treatment. Over the study period, there was no change in the PGD incidence; however, there was an increase in the recipient pretransplantation use of amiodarone. The rate of 30‐day mortality was significantly elevated in those with PGD versus those without PGD (6.06% vs 0.92%, = .01). Despite recent advancements, incidence of PGD remains high. Understanding associated risk factors may allow for implementation of targeted therapeutic interventions.  相似文献   
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