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101.
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Background

Although radiographic coxa profunda has been considered an indicator of acetabular overcoverage, recent studies suggest that radiographic coxa profunda is a nonspecific finding seen even in hip dysplasia. The morphologic features of coxa profunda in hip dysplasia and the frequency with which the two overlap are not well defined.

Questions/purposes

We determined (1) the prevalence of radiographic coxa profunda in patients with hip dysplasia; (2) the morphologic differences of the acetabulum and pelvis between patients with hip dysplasia and control subjects; and (3) the morphologic differences between hip dysplasia with and without coxa profunda.

Methods

We retrospectively reviewed the pelvic radiographs and CT scans of 70 patients (70 hips) with hip dysplasia. Forty normal hips were used as controls. Normal hips were defined as those with a lateral center-edge angle between 25° and 40°. Coxa profunda was defined as present when the acetabular fossa was observed to touch or was medial to the ilioischial line on an AP pelvic radiograph. CT measurements included acetabular version, acetabular coverage, acetabular depth, and rotational alignment of the innominate bone.

Results

The prevalence of coxa profunda was 44% (31 of 70 hips) in dysplastic hips and 73% (29 of 40 hips) in the control hips (odds ratio, 3.32; 95% CI, 1.43–7.68). Dysplastic hips had a more anteverted and globally shallow acetabulum with inwardly rotated innominate bone compared with the control hips (p < 0.001). Dysplastic hips with coxa profunda had a more anteverted acetabulum (p < 0.001) and inwardly rotated innominate bone (p < 0.002) compared with those without coxa profunda, whereas the acetabular coverage and depth did not differ between the two groups, with the numbers available.

Conclusions

Radiographic coxa profunda was not a sign of increased acetabular coverage and depth in patients with hip dysplasia, but rather indicates classic acetabular dysplasia, defined by an anteverted acetabulum with anterolateral acetabular deficiency and an inwardly rotated pelvis. Thus, the presence of coxa profunda does not indicate a disease in addition to hip dysplasia, and the conventional maneuvers during periacetabular osteotomy are adequate for these patients.

Level of Evidence

Level IV, diagnostic study.  相似文献   
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No reports have described experiments designed to determine the strength characteristics of spinal nerve roots and rami radiculares for the purpose of explaining the complexity of symptoms of medullary cone lesions and cauda equina syndrome. In this study, to explain the pathogenesis of cauda equina syndrome, monoaxial tensile tests were performed to determine the strength characteristics of spinal nerve roots and rami radiculares, and analysis was conducted to evaluate the stress-strain relationship and strength characteristics. Using the same tensile test device, the nerve root and ramus radiculares isolated from the spinal cords of pigs were subjected to the tensile test and stress relaxation test at load strain rates of 0.1, 1, 10, and 100 s-1 under identical settings. The tensile strength of the nerve root was not rate dependent, while the ramus radiculares tensile strength tended to decrease as the strain rate increased. These findings provide important insights into cauda equina symptoms, radiculopathy, and clinical symptoms of the medullary cone.  相似文献   
108.
Cyclin D1 overexpression is remarkably frequent in several human carcinomas and is believed to be a critical event in oncogenesis. We examined cyclin D1 expression, p53 expression, and the Ki-67 labeling index by immunostaining in human gallbladder mucosa in conditions varying from normal to malignant tissue. We also examined K-ras codon 12 mutations in these tissues with a two-step polymerase chain reaction. Nuclear cyclin D1 overexpression was observed in 48% of carcinomas occurring independently of adenoma, but not in adenomas, carcinomas arising in adenomas, or nonneoplastic lesions. Cytoplasmic cyclin D1 overexpression was observed in about 15% of abnormal specimens, irrespective of the type of epithelial abnormality. Carcinomas showing nuclear cyclin D1 overexpression had significantly higher Ki-67 labeling indexes than those with no overexpression. Moderately to poorly differentiated adenocarcinomas showed a higher incidence of nuclear cyclin D1 overexpression than papillary to well differentiated carcinomas. Specimens with cyclin D1 overexpression showed a high incidence of lymph permeation, venous permeation, and lymph node metastasis. We conclude that nuclear cyclin D1 overexpression is a critical event importantly associated with cell proliferation and invasive growth in gallbladder carcinogenesis, and that cyclin D1 immunostaining may become a useful marker for evaluating gallbladder carcinomas. Received: March 9, 1999 / Accepted: July 23, 1999  相似文献   
109.
A case of acinar-islet cell carcinoma presenting as insulinoma is reported. The patient was a 28-year-old man who presented with two convulsive episodes. Fajans' index [immunoreactive insulin (IRI; μU/ml/ glucose mg/dl)] and Turner's [IRI (μU/ml) × 100/glucose (mg/dl)—30] index were high (2.8 and 308, respectively), as were serum proinsulin levels (550pg/ml). Abdominal computed tomography and angiography revealed a highly vascular tumor in the pancreatic tail and several similar tumors in the liver. Histologic features of a biopsy specimen from a hepatic tumor were those of a malignant pancreatic endocrine tumor. Insulin secretion by the liver metastases was confirmed by venous sampling after arterial stimulation with calcium. These findings led us to diagnose malignant insulinoma with liver metastases. Serum levels of α-fetoprotein and trypsin were markedly elevated, to 2234ng/ml (normal <10) and 22000ng/ml (normal<460) respectively, and these levels continued to rise with further growth of the liver metastases. Immunohistochemically, the metastatic liver tumor specimen was positive for α-fetoprotein, α1-antichymotrypsin, chromogranin A, and neuron-specific enolase. These findings of amphicrine features in the tumor were indicative of acinar-islet cell carcinoma that produced α-fetoprotein and trypsin in addition to insulin.  相似文献   
110.
The purpose of this study was to test the hypothesis that tumor necrosis factor-alpha (TNF-alpha) rapidly antagonizes the beta-adrenergic responses of the chloride current and to clarify the intracellular mechanisms responsible for the anti-adrenergic action. The whole-cell patch-clamp technique was used to monitor the anti-adrenergic effects of TNF-alpha on the cAMP-dependent chloride current (I(Cl)) recorded from isolated guinea-pig ventricular myocytes. Ramp pulses (+/-120 mV; dv/dt = +/-0.4 V/s) were applied from the holding potential of -40 mV. TNF-alpha rapidly (<15 min) inhibited the isoproterenol (Iso, 0.1 micromol/L)-induced I(Cl) in a concentration-dependent manner (30-1,000 U/ml, IC (50) = 144 U/ml, n=30). The inhibitory action of TNF-alpha was also observed when I(Cl) had been previously stimulated by 1 micromol/L forskolin (n=5). Prior exposure of myocytes to 5 microg/ml pertussis toxin (PTX) hardly affected the anti-adrenergic action of TNF-alpha (n=4). However, when I(Cl) was induced by both 8-bromo-cAMP (100 micromol/L) and isobutylmethylxanthine (0.1 mmol/L), TNF-alpha (1,000 U/ml) failed to decrease I(Cl) amplitude (n=5). Prior exposure of myocytes to 5 mg/ml pertussis toxin (PTX) hardly affected the anti-adrenergic action of TNF-alpha (n=4). Furthermore, despite of the presence of nitro-L-arginine methyl ester (0.1 mmol/L), a nitric oxide synthase (NOS) inhibitor, TNF-alpha reversed the Iso-induced increase in I(Cl) (n=5). These results suggest that TNF-alpha rapidly antagonizes the beta-adrenergic responses of I(Cl) by reducing cAMP concentration. This anti-adrenergic action is mediated by neither the PTX-sensitive G proteins regulatory pathway nor constitutive NOS activation.  相似文献   
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