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31.
BACKGROUND: Our previous study reported that cerebral oxygen extraction fraction (OEF) increased in hemodialysis patients with anemia. The increased OEF suggests that the cerebral vasodilatory capacity might be impaired in these patients. To clarify this issue, we measured the CO2 response in patients with anemia secondary to chronic renal failure (CRF) using positron emission tomography (PET). METHODS: Ten anemic patients with CRF (6 females and 4 males) and 6 age-matched normal controls were studied. The underlying diseases of CRF were glomerulonephritis in 8 patients, systemic lupus erythematosus (SLE) in one patient, and hypertension in one patient; in this cohort, 5 patients were on hemodialysis treatment and the remaining 5 patients were in a pre-hemodialysis state. The cerebral blood flow (CBF) was measured by the O-15 H2O bolus injection method with each patient in a resting state and during 5% CO2 inhalation. The CO2 response was estimated as the percentage change of CBF per 1 mm Hg change of PaCO2. RESULTS: The CO2 response was significantly attenuated in anemic patients with CRF in comparison to the normal controls, and it inversely correlated with the severity of anemia. There was no significant difference in the CO2 response between the hemodialysis and pre-hemodialysis patients. The CO2 response significantly correlated with CBF and the cerebral metabolic rate for oxygen (CMRO2) at rest, however, it did not correlate with OEF and cerebral blood volume (CBV). CONCLUSIONS: The present study revealed the existence of a reduced cerebral vasodilatory capacity in anemic patients with CRF, suggesting that chronic hypoxic brain damage might play a role in the impaired cerebrovascular response to CO2.  相似文献   
32.
Pathological fractures caused by metastatic malignant disease have been the subject of increasing interest in recent years. This article describes our experience with the treatment of metastatic bone disease of the upper extremity and our attempt to clarify the indications for different surgical procedures. Of 53 patients with metastatic lesions to the upper extremity, 20 who had been surgically treated were analyzed retrospectively. These comprised 13 men and 7 women with a mean patient age of 62 years. The most common primary tumors to metastasize were lung and liver, with the humerus involved in 12 cases and the scapula and forearm in 4 cases each. Four patients with scapula and forearm involvement underwent tumor resection due to uncontrollable tumor size, while 3 were successfully treated by selective arterial embolization. Three metastases to the humeral head were reconstructed with endoprosthesis, but functional restriction was noted. Five cases with metastases to the humeral shaft were treated with tumor curettage, internal fixation using intramedullary nailing, adjuvant cryosurgery, and cementing. This achieved good results for pain relief and functional restoration with minimal complications. Two metastases to the humeral condyle were unable to be stabilized with plate and locking screws. Metastatic lesions to the scapula and forearm are commonly treated nonsurgically, but some patients with uncontrollable tumor mass require surgical resection. Endoprosthetic replacement is recommended if the lesion involves the humeral head or condyle. Most patients with the humeral shaft lesion are likely to benefit from tumor curettage, intramedullary nailing with locking screw, and cementing.  相似文献   
33.
Hypothermia is a potential therapy for cerebral hypoxic ischemic injury of not only adults but also neonates. However, the side effects of hypothermia in the developing brain, where a massive amount of neurogenesis occurs, remain unclear. We investigated the proliferation of neural progenitor cells by systemic application of the thymidine analog 5-bromodeoxyuridine (BrdU) in neonatal rats in a severe hypothermic environment. The rat pups were divided into two groups, a hypothermia group (30 degrees C: n=10) and a normothermia group (37 degrees C: n=10). After the pups were placed for 21 h in each environment, 100 mg/kg/day of BrdU was injected intraperitoneally to label dividing cells, and then the pups were sacrificed at 24 h. We examined the number of BrdU-labeled cells in the subventricular zone of the periventricle and the subgranular zone of the dentate gyrus. In the hypothermic environment, BrdU-labeled cells significantly decreased in number in the dentate gyrus, but not in the periventricular region. Thus, the severe hypothermic environment induced a decrease of neurogenesis in the neonatal rat. These observations are noteworthy regarding clinical hypothermia therapy following cerebral hypoxic ischemic injury during the perinatal period.  相似文献   
34.
Intramuscular hemangioma of the upper extremity in infants and children   总被引:1,自引:0,他引:1  
PURPOSE: Intramuscular hemangiomas (IMHs) are benign tumors comprising just 0.8% of all hemangiomas and are extremely rare in the upper limbs. These tumors can pose diagnostic as well as therapeutic challenges for orthopaedic surgeons, especially in younger children. We reviewed cases of IMH of the upper extremity in infants and children from our institute. METHODS: Six consecutive patients underwent surgical treatment for IMH in our hospital. There were 4 girls and 2 boys. Long-standing pain and swelling were common symptoms except in a 1-year-old boy. Tumors were evaluated by radiography, computed tomography, magnetic resonance imaging, and angiography. RESULTS: After a mean follow-up of 42 months, all patients except one were free of pain and without tumor recurrence or functional impairment. Minimal symptoms remained in a 6-year-old boy who underwent biopsy only. CONCLUSION: Magnetic resonance imaging is the most useful evaluation for IMH because it not only delineates the extent of tumor but also reveals characteristic structures. For young children with IMH, wide excision is the treatment of choice to prevent local recurrence, but every patient should be treated individually after evaluating the patient's age, tumor location and invasion, and cosmetic considerations. LEVEL OF EVIDENCE: Therapeutic study-level III.  相似文献   
35.
A rare case of cecal volvulus in cerebral palsy that was preoperatively diagnosed and surgically treated without complications is herein reported. A 45-year old man, who had been treated for cerebral palsy as a result of a neonatal cerebral hemorrhage, was admitted to our hospital because of abdominal pain and vomiting. A plain abdominal X-ray film showed evidence of a huge quantity of gas in the left abdomen. Using a gastrographin enema from the colonoscope, an obstruction of the ascending colon was revealed with tapering of the lumen. A computed tomography scan showed a grossly dilated air-distended bowel in the left abdomen and soft tissue with internal architecture containing swirling strands of soft tissue and fat attenuation. An emergency laparotomy was performed. During the laparotomy the ileocecal region, which was unfixed at the retroperitoneum, was found to be twisted counterclockwise by 360° around the mesentery with the terminal ileum, thus resulting in a diagnosis of cecal volvulus. We therefore conducted an ileocecal resection. Cecal volvulus is an uncommon form of intestinal obstruction with a high mortality rate and may present considerable difficulty in diagnosis. Although cecal volvulus is rare as a cause of intestinal obstruction, it should be included in the differential diagnosis of bowel obstruction in cerebral palsy.  相似文献   
36.
This study was designed to determine the optimum treatment for a superficial esophageal cancer involving the mucosal or submucosal layer of the esophagus. The subjects were 150 patients with a superficial esophageal cancer who underwent endoscopic mucosal resection (EMR) or esophagectomy in Kurume University Hospital from 1981 to 1997. The mortality and morbidity rates, survival rate, and recurrence rate were retrospectively compared for (1) 35 patients who underwent EMR and 37 patients who underwent esophagectomy for a mucosal esophageal cancer and (2) 45 patients who underwent extended radical esophagectomy and 33 patients who underwent less radical esophagectomy for a submucosal esophageal cancer. Among the 72 patients with a mucosal cancer, lymph node metastasis/recurrence was observed in only one (1%); whereas of 78 patients with a submucosal cancer it was observed in 30 (38%). Among patients with a mucosal cancer the mortality and morbidity rates after EMR were lower than for those after esophagectomy. The survival rate after EMR was the same as that after esophagectomy. No recurrence was observed after either treatment modality. Among the patients with a submucosal cancer, the survival rate was higher and the recurrence rate lower after extended radical esophagectomy; than after less radical esophagectomy; the mortality and morbidity rates after extended radical esophagectomy were the same as those after less radical esophagectomy. Multivariate analysis demonstrated that the treatment modality (EMR versus esophagectomy) did not influence the survival of patients with a mucosal esophageal cancer, whereas it strongly influenced the survival of patients with a submucosal esophageal cancer. We concluded that EMR was the mainstay of treatment for a mucosal esophageal cancer, and extended radical esophagectomy was the mainstay of treatment for a submucosal esophageal cancer.  相似文献   
37.
Background: It is recognized that matrix metalloproteinase‐3 (MMP‐3) is abundantly expressed in active rheumatoid synovium, and that serum level of MMP‐3 is a useful marker for diagnosis of rheumatoid arthritis and for evaluation of prognosis in joint destruction. Little is known about serum MMP‐3 levels in haemodialysis (HD) patients, and thus, the association between serum MMP‐3 and dialysis‐related amyloidosis (DRA) has yet to be elucidated. Methods: Serum levels of MMP‐3 were measured by enzyme immunoassay in 150 HD patients, 90 without DRA and 60 with DRA, before HD. Simple regression analysis was performed to investigate the relationship between serum level of MMP‐3 and clinical parameters, including age, HD duration, C‐reactive protein and β2 microglobulin (BMG). Results: Serum levels of MMP‐3 were significantly higher in HD patients with DRA than in HD patients without DRA (258.2 ± 118.1 vs 201.5 ± 98.4 pg/mL, P = 0.0017), and both levels were significantly higher than those of healthy subjects (45.6 ± 13.4 pg/mL, P < 0.0001). Serum MMP‐3 levels significantly correlated with serum levels of BMG (r = 0.197, P = 0.0164) and HD duration (r = 0.168, P = 0.0427). Moreover, serum MMP‐3 levels significantly correlated with serum BMG levels in HD patients without DRA (r = 0.341, P = 0.0012), but not in HD patients with DRA. Conclusion: Our results suggest that matrix metalloproteinase activity increases in HD patients, which may be associated with BMG and DRA.  相似文献   
38.
OBJECTIVE: To compare postoperative maxillary stability following Le Fort I osteotomy for the correction of occlusal cant as compared with conventional Le Fort I osteotomy for maxillary advancement. STUDY DESIGN: The subjects were 40 Japanese adults with jaw deformities. Of these, 20 underwent a Le Fort I osteotomy and intraoral vertical ramus osteotomy (IVRO) to correct asymmetric skeletal morphology and inclined occlusal cant. The other 20 patients underwent a Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO) to advance the maxilla. Lateral and posteroanterior cephalograms were taken postoperatively and assessed statistically. Thereafter, the 2 groups were followed for time-course changes. RESULTS: There was no significant difference between the 2 groups with regard to time-course changes during the immediate postoperative period. CONCLUSION: This suggests that maxillary stability after Le Fort I osteotomy for cant correction does not differ from that after Le Fort I osteotomy for maxillary advancement.  相似文献   
39.
Fatty acid-binding proteins (FABPs) bind unsaturated fatty acids and lipid peroxidation products during tissue injury from hypoxia. We evaluated the potential role of L-type FABP (L-FABP) as a biomarker of renal ischemia in both human kidney transplant patients and animal models. Urinary L-FABP levels were measured in the first urine produced from 12 living-related kidney transplant patients immediately after reperfusion of their transplanted organs, and intravital video analysis of peritubular capillary blood flow was performed simultaneously. A significant direct correlation was found between urinary L-FABP level and both peritubular capillary blood flow and the ischemic time of the transplanted kidney (both P < 0.0001), as well as hospital stay (P < 0.05). In human-L-FABP transgenic mice subjected to ischemia-reperfusion injury, immunohistological analyses demonstrated the transition of L-FABP from the cytoplasm of proximal tubular cells to the tubular lumen. In addition, after injury, these transgenic mice demonstrated lower blood urea nitrogen levels and less histological injury than injured wild-type mice, likely due to a reduction of tissue hypoxia. In vitro experiments using a stable cell line of mouse proximal tubule cells transfected with h-L-FABP cDNA showed reduction of oxidative stress during hypoxia compared to untransfected cells. Taken together, these data show that increased urinary L-FABP after ischemic-reperfusion injury may find future use as a biomarker of acute ischemic injury.  相似文献   
40.
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   
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