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991.
992.
OBJECTIVE: To assess high-sensitivity C-reactive protein (hsCRP) level as a measure of low-grade inflammation in relation to Modic vertebral end-plate marrow signal change on magnetic resonance imaging (MRI) in patients with chronic low back pain. METHODS: All patients hospitalized for chronic low back pain in our institution were prospectively enrolled in this pilot study. Serum hsCRP concentration was measured by immunoturbidimetric assay. MR images were evaluated independently by a panel of 2 spine specialists and a radiologist. Recording of clinical parameters, MRI evaluation, and hsCRP level of each patient was blinded. RESULTS: Three groups of 12 consecutive patients (Modic 0, Modic I, and Modic II signal changes on MRI) were prospectively selected. Serum hsCRP level was significantly different in the 3 groups (P = 0.002) and especially high in the Modic I group (P = 0.002 compared with Modic 0 and II groups): mean +/- SD 1.33 +/- 0.77 mg/liter in the Modic 0 group, 4.64 +/- 3.09 mg/liter in the Modic I group, and 1.75 +/- 1.30 mg/liter in the Modic II group. The only difference in clinical parameters among the 3 groups (P = 0.001) was that the worst painful moment during the previous 24 hours occurred during the late night and morning for all Modic I patients (P = 0.001 compared with Modic 0 and P = 0.002 compared with Modic II). CONCLUSION: Low-grade inflammation indicated by high serum hsCRP level in patients with chronic low back pain could point to Modic I signal changes. This result could help physicians predict the patients with Modic I signals to more precisely prescribe the correct imaging procedure and local antiinflammatory treatment in such patients.  相似文献   
993.
Understanding of the maternal syndrome of pre-eclampsia has greatly improved over the past 5 years. Specifically, the notion has emerged that the placenta is a source of antiangiogenic factors, such as soluble fms-like tyrosine kinase 1, that can progressively impair the mother's vascular and glomerular function throughout pregnancy. This impairment can be harmless during normal pregnancy, but in cases of defective placentation, concentrations of antiangiogenic factors increase to a level that compromises vital vascular functions in the short term and jeopardizes long-term maternal and fetal outcomes. In both pre-eclamptic and healthy pregnancies, the transient imbalance between angiogenic and antiangiogenic factors elicited by pregnancy acts as a 'stress test' for the endothelium, particularly in the glomerular capillary bed. Women who do not pass this test (i.e. those who develop pre-eclampsia or gestational hypertension) should be screened for glomerular disease, and their cardiovascular risk should be carefully monitored throughout life.  相似文献   
994.
An ultrasonographic study was carried out in 25 infants (50 knees) with Down syndrome, whose age ranged from zero to 24 months, average being 13.2 months; 13 were males and 12 were females. The ultrasonographic investigation was performed with the knee being in full extension for the transversal view and in 30 degrees flexion for the sagittal view. The Insall-Salvati index and femoral cartilaginous sulcus angle were measured. Insall-Salvati index values ranged from 1.06 to 1.15 (average 1.10), with standard deviation of 0.16. No significant differences were observed with regard to Insall-Salvati index values in normal children. The femoral cartilaginous sulcus angle in infants with Down syndrome ranged from 152.7 to 155.8 degrees (average 154.3) with standard deviation of 7.959. In Down syndrome we noticed significant difference as compared to the normal values. The authors suggest that ultrasonography is useful in Down syndrome for an early diagnosis of instability of the patella.  相似文献   
995.
Background The aim of this study was to assess the incidence, characteristics, treatment, and survival of patients with tracheal malignancies in the Netherlands. Methods All cases of tracheal cancer entered into the database of the Netherlands Cancer Registry in the period 1989–2002 were selected. Data on histological type, age at time of diagnosis, treatment, and survival were analyzed retrospectively. Results The annual incidence was 0.142 per 100,000 inhabitants (308 cases, of which 15 were found incidentally at autopsy). Of these, 72% were men. In 52.9%, the histological type was squamous cell carcinoma and in only 7.1% adenoid cystic carcinoma (ACC). Mean age at time of diagnosis was 64.3 years. Of the 293 patients diagnosed while alive, 34 patients underwent surgical resection (11.6%), 156 patients received radiotherapy (53.2%), and 103 patients neither (35.4%). Median survival of all 293 patients was 10 months (mean 28 months) with 1-year, 5-year, and 10-year survival rates of 43%, 15%, and 6%, respectively. The prognosis of patients with ACC was significantly better. The 5-year survival rate in patients who underwent surgical resection was 51%, and the 10-year survival rate in these patients was 33%. Conclusion The prognosis of patients with a tracheal malignancy is usually poor. Surgical treatment, however, can lead to good survival rates; still, this is currently only used in selected patients, even though it would seem to be possible in more cases in view of the technical advances in the field of tracheal surgery. Centralizing the care and treatment of tracheal cancers and implementing a more assertive attitude towards this disease could make surgery accessible to a larger number of patients. Data from the literature show that this would lead to better survival in patients with a tracheal malignancy.  相似文献   
996.
Background The value of spleen preservation during distal pancreatectomy (DP) still remains controversial. Spleen-preserving DP with excision of the splenic artery and vein is a simplified technique for spleen preservation. The aim of this study was to compare the postoperative course of DP with or without splenectomy. Patients and Methods From 1990 to 2005, 38 consecutive patients with benign or low-grade malignant disease underwent a spleen-preserving DP operation with excision of the splenic artery and vein (Conservative Group). They were compared with 38 patients who underwent conventional DP with splenectomy over the same time period (Splenectomy Group) and who had been matched for age, American Society of Anesthesiologists (ASA) score, and pathological diagnosis. Postoperative courses were analyzed and compared between the Conservative Group and Splenectomy Group. Results Spleen preservation was effective in 36 of the 38 attempts (95%). Postoperative complications – in particular, infectious intra-abdominal complications – were significantly higher in the Splenectomy Group (34 and 18%, respectively) than in the Conservative Group (13 and 3%, respectively) (P = 0.03 and P = 0.02, respectively). The length of the surgery, perioperative blood loss or transfusions, perioperative mortality and length of hospital stay did not differ between the two groups. Univariate analysis showed that splenectomy was the only risk factor for postoperative complication. Conclusions Spleen-preserving DP with excision of the splenic artery and vein is a fast, safe and effective procedure associated, in this series, with a reduction of postoperative complications relative to conventional DP with splenectomy. This technique should be considered in patients with benign or low-grade malignant disease of the pancreas. The authors declare that there are no competing interests.  相似文献   
997.
998.
Necrotizing enterocolitis (NEC) is the most common and lethal disease that affects the gastrointestinal (GI) tract of the premature infant. The etiology of NEC remains undefined. The only consistent epidemiological precursors for NEC are prematurity and enteral alimentation. Various inflammatory mediators, including tumor necrosis factor (TNF)-a, interleukin (IL)-1, IL-6, IL-8, IL-10, IL-18, platelet-activating factor (PAF), and nitric oxide (NO) have been implicated in the pathogenesis of NEC, but the kinetics and role of these agents are ill-defined. Currently, there are no biomarker predictors of NEC risk and severity. Sera or tissue from early time points in the development of the disease may help delineate early inflammatory events that predispose an individual to NEC, thus providing an interventional opportunity. We suggest that the lack of diagnostic and therapeutic modalities for NEC are due to the absence of a systems view of the disease, which in turn is hindered by a lack of sensitive physiological measurements that predict perturbations in the intestinal tissue compartment and an inability to reliably test serial samples for the presence of inflammatory mediators in small volumes and in a high-throughput manner. Computational modeling is a useful tool in the study of complex systems such as the inflammatory process. Computation models provide an “existence proof” for a given mechanism, uncover subtle inconsistencies between the underlying hypotheses and quantitative data, and force one to ask how much is known. We suggest that a properly validated and calibrated mathematical model of inflammation and its pathologic consequences in NEC will be useful for predicting the physiologic and biologic response in infants suffering from the disease.  相似文献   
999.
1000.
The added precision and steadiness of a robotically held camera enables the performance of more complex procedures laparoscopically. In contrast to typical laparoscope holders, the modified lightweight robotic endoscope, the ViKY system is particularly compact, simple to set up and use, and occupies no floor space. Ease and safety of setup was confirmed in a porcine model and several common general surgical procedures were performed. The sterilizable endoscope manipulator is sufficiently small to be placed directly on the operating room table without interfering with other handheld instruments during minimally invasive surgery. The endoscope manipulator and its user interface were tested and evaluated by several surgeons during a series of 5 minimally invasive surgical training procedures in a porcine model. The endoscope manipulator described has been shown to be a practical device with performance and functionality equivalent to those of commercially available models, yet with greatly reduced size, weight, and cost.  相似文献   
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