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81.
A 11-year-old female with Noonan syndrome presented with occipito-atlantal dislocation and upper cervical cord compression due to C1 dysplasia and basilar invagination. Computed tomography (CT) of the cervical spine showed dysplasia of the C1 posterior arch and bilateral dislocation of the occipito-atlantal joints. Dynamic lateral radiography revealed no instability at the occipito-atlantal joints. CT also demonstrated basilar invagination. The tip of the odontoid process extended above the Chamberlain line by 9 mm and the McGregor line by 10 mm. Whole spinal radiography showed no scoliosis. C1 laminectomy was performed with instrumented occipito-C2 fixation. The postoperative course was uneventful, and magnetic resonance imaging revealed sufficient decompression of the upper cervical cord at 2 months after surgery. CT demonstrated solid bony fusion between the occipital bone and C2 at 8 months after surgery. Cervical neuraxial malformations are rare in patients with Noonan syndrome.  相似文献   
82.
A lobectomy with systemic lymphadenectomy is a standard surgical procedure for a resectable lung cancer. However there is not a consensus on the limited surgery. A 60-year-old man underwent left upper lobe partial resection for small size lung adenocarcinoma under video assisted thoracic surgery (VATS). Fifty-six months after the operation, a computed tomography (CT) scan showed a local recurrence on the staple-line. A positron emission tomography (PET) scan showed an additional port site recurrence, which wasn't showed by a CT scan. He underwent left upper lobectomy and port site resection.  相似文献   
83.
Tracheal chondrosarcomas are rare, with only 14 cases previously documented. We report a case of chondrosarcoma of the trachea and review other published cases. Our patient was a 34-year-old man who began to feel shortness of breath 8 months after initial hemoptysis. Transverse and coronal computed tomography demonstrated a tumor that was obstructing nearly 80% of the tracheal lumen at the thoracic inlet. A bronchoscopic biopsy specimen led to an initial diagnosis of chondroma. Five tracheal rings from the third to the seventh including the tumor were completely resected, and an end-to-end anastomosis was performed. The histological diagnosis of the surgical specimen showed it to be a chondrosarcoma. The patient was alive without recurrence at 6 years 4 months after surgery. Because recurrence after incomplete resection and malignant transformation can occur with chondromas, radical resection of the trachea is recommended for all cartilaginous tumors of the trachea.  相似文献   
84.
BACKGROUND: Sepsis is an arginine-deficient state and is associated with overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). It has been indicated that low plasma levels of arginine are related to high mortality rates in sepsis. Arginine, however, is also known to be a precursor of NO. Therefore, administration of arginine in septic patients remains controversial. We examined the effects of co-administration of arginine and aminoguanidine, a selective iNOS inhibitor, on sepsis, using rat models. METHOD: Sepsis was induced in rats by cecal ligation and puncture (CLP). Effects of separate and combined administration of arginine and aminoguanidine were investigated by comparing plasma levels of arginine, expressions of heme oxygenase (HO)-1 and HO-2 in liver and lung, and nitrite + nitrate (NOx) excretion in urine, as well as neuroendocrine responses in urine in the early phase of sepsis. Seven-day survival rates were also examined. RESULTS: A combination of arginine and aminoguanidine recovered the plasma level of arginine at 6 h post-CLP, decreased expression of HO-1 in liver and lung at 24 h post-CLP, decreased urinary excretion of epinephrine, norepinephrine, dopamine, and 17-hydroxycorticosteroid in the first 24 h post-CLP, and increased 7-d survival. CONCLUSION: It is demonstrated that administration of arginine together with the selective iNOS inhibitor in the early phase of sepsis restores plasma arginine, reduces oxidative stress by probably maintaining NO derived from constitutive NOS, and attenuates neuroendocrine stress responses. This co-administration may be a beneficial treatment approach against sepsis.  相似文献   
85.
We report two cases of prostatic carcinoma presenting as neck lymph node metastases. Case 1: A 56-year-old man was admitted to our hospital with the chief complaint of left lower abdominal pain. A lymph node was palpable on the left side of the neck swollen. Rectal examinations revealed prostatic stony-hard mass. Computed tomography showed a swollen neck and paraaortic lymph nodes on the left side. PSA level was 380 ng/ml. Transperineal prostatic biopsy revealed moderately differentiated adenocarcinoma, and neck lymph node biopsy also revealed metastatic adenocarcinoma. We diagnosed him with prostatic carcinoma stage D2 (LYM). He underwent hormonal therapy (TAB) but died 13 months later. Case 2: A 66-year-old man was admitted to our hospital with the chief complaint of a large palpable mass on the left side of the neck. Resection of this mass revealed metastatic adenocarcinoma. Rectal examination revealed no malignant lesions, but the PSA level was high, 1,700 ng/ml. Transperineal prostatic biopsy revealed moderately differentiated adenocarcinoma. Computed tomography revealed paraaortic and pelvic lymph node metastases and bone scintigram revealed abnormal uptake, bone metastases. We diagnosed him with prostatic carcinoma stage D2 (LYM OSS). We performed bilateral testectomy followed by hormonal therapy (TAB). The lymph node metastases disappeared after 4 months of therapy.  相似文献   
86.
N Furusawa  H Baba  N Miyoshi  Y Maezawa  K Uchida  Y Kokubo  M Fukuda 《Spine》2001,26(10):1110-1116
STUDY DESIGN: Surgically obtained cervical herniated intervertebral discs were examined histologically and immunohistochemically. The production of nitric oxide (NO) in the local tissue was examined using the electron spin resonance (ESR) method. OBJECTIVES: To investigate the local histologic and immunohistochemical changes in cervical disc herniation, including NO production, and to compare such changes with those in autopsy cases. SUMMARY OF BACKGROUND DATA: Very little is known about the histopathologic processes of cervical disc herniation. In addition, no information is available on the level of in vivo NO production in cervical disc herniation. METHODS: Thirty-six herniated cervical discs obtained from 31 patients were immunohistochemically examined for localization of blood vessels, matrix metalloproteinase (MMP)-3, and inducible NO synthetase (iNOS). We also compared the production of NO, measured by the ESR method, in eight specimens with that of five control discs obtained from fresh cadavers. RESULTS: The presence of herniated discs correlated with the degeneration of cartilaginous endplate and torn anulus fibrosus. Formation of new blood vessels around the herniated discs was detected, using von Willebrand factor antibody, in seven uncontained hernias and 20 contained hernias. Immunohistochemical studies showed the presence of cells positive for MMP-3 (chondrocytes), iNOS (chondrocytes and granulation tissue) in cervical disc hernias. ESR analysis showed a significantly higher NO production in herniated cervical discs than in disc samples of fresh cadavers. CONCLUSIONS: Herniated cervical intervertebral disc is characterized by the presence of an inflammatory process associated with neovascularization and increased expression of MMP-3. Production of NO was markedly high in both contained- and uncontained-type hernias.  相似文献   
87.
In cruciate-retaining (CR) type TKA, the increase in posterior condylar offset (PCO) is considered to be correlated to flexion angle acquired postoperatively according to the article reported by Bellemans (J Bone Joint Surg Br 84:50–53, 2002). However, the significance of PCO seems to differ according to the size of joints. We therefore have defined a new parameter of posterior condylar offset ratio (PCOR) on the lateral view of plain X-ray photographs and studied the relationship between PCOR and postoperative flexion status in posterior-stabilized (PS) type TKA. Flexion status includes two parameters, such as postoperative flexion angle (FA) and flexion achievement rate (AR). The subjects of this study were 160 knees (16 males and 144 females, average 75 years.) with PS type TKA for osteoarthritic knees between 1999 and 2003 at our institution, more than at least 1 year postoperative follow-up. In the study of FA, patients with FA of less than 100° were divided into Group L (n = 28), patients with FA of 130° and greater were divided into Group H (n = 58). In the study of AR, patients with AR of less than 100% were divided into Group P (n = 46), patients with AR of 120% and greater were divided into Group G (n = 22). PCOR was statistically compared in each group, respectively. In FA, PCOR in Group L (0.385) was significantly lower (P = 0.027) than that in Group H (0.428). In AR, PCOR in Group P (0.376) was significantly lower (P = 0.0018) than that in Group G (0.456). We have concluded, though there are many factors influencing the range of movement after TKA, our newly defined PCOR could possibly serve as a parameter of postoperative flexion status of PS type TKA on plain X-ray photographs. No benefits or funds were received in support of the study.  相似文献   
88.
STUDY DESIGN: A human cadaveric biomechanical study of fixation strength of an improved novel pedicle screw (NPS) with cement and a conventional screw. OBJECTIVE: To clarify whether the NPS has adequate fixation strength without leakage in vertebrae with low bone quality. SUMMARY OF BACKGROUND DATA: The fixation strength of pedicle screws decreases in frail spines of elderly osteoporotic patients. Augmentation of screw fixation with bone cement must be balanced against increased difficulty of screw removal and risk of cement leakage. We developed the NPS consisting of an internal screw and an outer sheath to mitigate the disadvantages of cement augmentation. METHODS: The T12 and L1 vertebrae obtained from 18 formalin preserved cadavers (11 males and 7 females; mean age, 82.7 y) were used. The mean bone mineral density was 0.39 +/- 0.14 g/cm2. The NPS was inserted into one pedicle of each vertebra and the control screw, a Compact CD2 screw, was inserted into the contralateral pedicle. Both screws were 6mm in diameter and 40 mm in length. Pull-out tests were performed at a crosshead speed of 10 mm/min. Cyclic loading tests were performed with a maximum 250 N load at 2 Hz until 30,000 cycles. RESULTS: Cement leakage did not occur in any of the specimens tested. The mean maximum force at pull-out was 760 +/- 344 N for the NPS and 346 +/- 172N for the control screw (P < 0.01). Loosening of 50% of the screws was observed after 17,000 cycles of the NPS and after 30 cycles of the control screw. The hazard ratio of loosening was 19.6 (95% confidence interval 19.3-19.9) (P < 0.001). CONCLUSIONS: The NPS showed a significantly higher mechanical strength than the control screw in both pull-out tests and cyclic loading tests. The NPS showed more than adequate strength without cement leakage.  相似文献   
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