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901.

Purpose

Wedging of the vertebral body on radiological examination is a valuable indicator of a vertebral compression fracture, although it can also be observed in subjects with no history of trauma. The purpose of this study was to elucidate the normative value of vertebral wedging at the thoracolumbar junction in asymptomatic healthy subjects for differential diagnosis of vertebral compression fractures using MRI.

Methods

A total of 115 subjects without back pain at the time of the examination and without history of spinal trauma was included (68 males, 47 females, mean age 49.5?years). They underwent MRI of the thoracic and lumbar spine, and the ratio of anterior vertical height to posterior vertical height of the vertebral body (APR) was determined from T10 to L2 on T2 weighted sagittal images.

Results

APR was 0.92?±?0.08 at T10, 0.92?±?0.08 at T11, 0.90?±?0.06 at T12, 0.89?±?0.06 at L1, and 0.90?±?0.07 at L2, indicating that vertebral bodies at the thoracolumbar junction appear wedge-shaped rather than rectangular. Males, thinner subjects, smokers, and subjects with abnormalities of the endplates such as a Schmorl nodule had a significantly smaller APR than females, fatter subjects, non-smokers, and those without endplate abnormalities.

Conclusion

The normative values of APR obtained in the present study can represent a valuable reference in the diagnosis of vertebral compression fracture to help prevent confusion with physiological vertebral wedging.  相似文献   
902.
At the end of August 2008, many areas in Japan were hit by concentrated downpour. Okazaki City, Aichi, where our hospital is located, suffered serious damage, including two fatalities. The resulting flooding inundated Okazaki City Hospital. Hospital functioning did not stop, but some devices were damaged by the water. There was no direct damage to the clinical laboratory area, but an abnormality in the measurement of Troponin-I occurred after the downpour. It was suggested that this measurement abnormality was caused by the pollution of the supplied water to the analyzer. In this report, I will describe the situation regarding the clinical laboratory during hospital flooding, and also report the unexpected measurement abnormalities that occurred after the downpour.  相似文献   
903.
Here we investigated the biomechanical properties of spinal segments in patients with degenerative lumbar spondylolisthesis (DLS) using a novel intraoperative measurement system. The measurement system comprised spinous process holders, a motion generator, a load cell, an optical displacement transducer, and a computer. Cyclic displacement of the holders produced flexion-extension of the segment with all ligamentous structures intact. Stiffness, absorption energy (AE), and neutral zone (NZ) were determined from the load-deformation data. Forty-one patients with DLS (M/F = 15/26, mean age 68.6 years; Group D) were studied. Adjacent segments with normal discs in six patients (M/F = 3/3, mean age 35 years) were included as a control group (Group N). Flexion stiffness was significantly lower in Group D than in Group N. The NZ, however, was significantly greater in Group D than in Group N. Thus, compared to normal segments, spinal segments with DLS had a lower flexion stiffness and a higher NZ. NZs in Group D were, however, widely distributed compared to those in Group N that showed NZ <2 mm/N in all cases, suggesting that the segment with DLS is not always unstable and that the segments with NZ >2 mm/N can be considered as unstable. A patent application for the intraoperative measurement system has been submitted.  相似文献   
904.
Background/Purpose  To examine whether vertical retrocolic duodenojejunostomy is superior to antecolic duodenojejunostomy with respect to gastric emptying in a prospective, randomized, controlled study of patients undergoing pylorus-preserving pancreaticoduodenectomy (PpPD). Methods  Thirty-five patients undergoing PpPD between March 2005 and July 2007 were enrolled in the study. All provided informed consent. During PpPD, the patients were randomly assigned to either the antecolic (antecolic group, n = 17) or vertical retrocolic route (vertical retrocolic group, n = 18) just before the reconstruction. Each patient ingested 13C-acetate in a liquid meal before surgery and on postoperative day (POD) 30. Gastric emptying variables (Tmax, T1/2) were determined and compared between groups. Results  Clinical delayed gastric emptying, defined as an inability of patients to take in an appropriate amount of solid food orally by POD 14, was found in 1 of 17 patients (6%) in the antecolic group and in 4 of 18 patients (22%) in the vertical retrocolic group, but the difference was not significant (P = 0.34). Tmax and T1/2 on POD 30 were prolonged in both groups in comparison to preoperative levels, but no significant difference was found between the two groups. Follow-up examinations revealed that gastric emptying had recovered to the preoperative level by POD 30 in approximately 80% of the patients, regardless of the reconstruction route. Conclusions  Vertical retrocolic duodenojejunostomy does not seem to offer an advantage with respect to gastric emptying.  相似文献   
905.
906.

Background

The authors present a modified interhemispheric approach for the distal ACA aneurysm to resolve several problems including the narrow surgical corridor, the difficulty of proximal control, and the aneurysmal projection toward the surgeon.

Methods

We refined the positions of the patient's head and the surgeon. The patient's head is fixed with flexion and tilted to the contralateral side. The surgeon sits on the contralateral side of the patient and not on the cranial side.

Results

The present approach allows the surgeon to comfortably use both hands in the horizontal operative filed, to obtain a minimum retraction of the brain, and to easily secure the proximal artery.

Conclusions

This modified interhemispheric approach is useful for a patient with the distal ACA aneurysm.  相似文献   
907.
908.
Mammary glands develop postnatally in response to the hypothalamic‐pituitary‐gonadal axis. Obesity‐induced changes in the local environment, however, retard mammary gland development during late pregnancy and lactation. To clarify the effects of obesity on fundamental duct development, we compared the mammary glands of nulliparous nonpregnant obese mice fed a high‐fat diet with those of lean mice fed a normal diet. Obese mice had enlarged mammary glands, reflecting fat pad size, whereas the ducts in obese mice showed a less dense distribution with less frequent branching. Additionally, the ducts were surrounded by thick collagen layers, and were incompletely lined with myoepithelium. Because leptin receptors were localized in the epithelium region and leptin that was highly expressed in the obese glands suppressed mammary epithelial cell proliferation in vitro, the present results suggest that obesity disrupts mammary ductal development, possibly by remodeling the mammary microenvironment and promoting the expression of such paracrine factors as leptin. Developmental Dynamics 238:1092–1099, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
909.
Neoplasm of follicular dendritic cells (FDC), follicular dendritic cell sarcoma (FDCS), is a rare tumor of intermediate to high-grade malignancy in lymph nodes and visceral organs. Reported herein is a case of FDCS arising from cervical lymph nodes in a 16-year-old Japanese boy, who died of the disease 3 years after diagnosis. The tumor cells were pale eosinophilic and elongated with euchromatic nuclei and were positive for CD21, clusterin, and CNA-42 on immunohistochemistry, as well as desmosome-like junctions on electron microscopy. The presence of microtubuloreticular structures (MTRS) in the tumor cells and associated lymphocytes characterized this case, suggesting some viral infection, although qualitative polymerase chain reaction of genomic and complementary DNA obtained from the tumor failed to demonstrate any viral infection at the laboratory level. The stimulation of dispersed tumor cells and peripheral blood mononuclear cells with mAb to CD3 and interleukin-2 was attempted; and the cell line established by the authors (FDCS-Sa) was stimulated with iododeoxyuridine. Virus-like particles (VLP) were successfully induced from each cellular source. The VLP, 100 nm in diameter, showed an electron-dense thorny envelope and granular core. This is the first case of FDCS with MTRS accompanying VLP production in vitro .  相似文献   
910.
Rationale  Surgical strategy for patients with hepatocellular carcinoma and portal vein tumor thrombus (PVTT) remains to be established. Methods  From 1990 to 2008, 48 hepatocellular carcinoma patients with PVTT detected by preoperative imaging underwent hepatic resection, and their clinical data were retrospectively analyzed. Possible prognostic factors for survival were analyzed with postoperative survival curves, and significant factors were determined by univariate and multivariate analysis. The frequency of postoperative severe complications was investigated for each prognostic factor. Results  Significant prognostic factors included patient age <60 years, serum total bilirubin (T-Bil) >0.8 mg/dl, serum aspartate aminotransferase >30 IU/L, serum alkaline phosphatase (ALP) >300 IU/L, tumor size >4 cm, PVTT in the main trunk (Vp4), and a surgical margin <1 mm by univariate analysis, and independent prognostic factors were serum T-Bil, ALP, and Vp4. No patient with Vp4 survived for more than 400 days after surgery, and frequency of postoperative severe complications in these Vp4 patients was significantly higher than in other Vp1–3 patients. Conclusion  Hepatic resection as a first-choice treatment should be carefully selected in patients with Vp4 unless emergent removal of the PVTT is required.  相似文献   
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