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791.
At this institution a new procedure has been developed that involves anastomosing one of the branches of the superficial temporal artery to one of the major trunks of the middle cerebral artery in the Sylvian fissure. This procedure has been performed in 22 cases to date. Clinical indications for this procedure have fallen into four major categories. This new type of anastomosis produces greater bypass flow than conventional cortical middle cerebral artery anastomoses, and may be a better therapeutic alternative in certain clinical situations. The preoperative and postoperative angiographic evaluation of these patients is discussed. The radiologic results in this series of patients are reviewed.  相似文献   
792.
In this study we have assessed sodium-calcium exchanger (NCX) protein over-expression on cell viability in primary rat cortical neuronal and HEK293 cell cultures when subjected to oxygen-glucose deprivation (OGD). In cortical neuronal cultures, NCX2 and NCX3 over-expression was achieved using adenoviral vectors, and following OGD increased neuronal survival from ≈20% for control vector treated cultures to ≈80% for both NCX isoforms. In addition, we demonstrated that NCX2 and NCX3 over-expression in cortical neuronal cultures enables neurons to maintain intracellular calcium at significantly lower levels than control vector treated cultures when exposed to high (9mM) extracellular calcium challenge. Further assessment of NCX activity during OGD was performed using HEK293 cell lines generated to over-express NCX1, NCX2 or NCX3 isoforms. While it was shown that NCX isoform expression differed considerably in the different HEK293 cell lines, high levels of NCX over-expression was associated with increased resistance to OGD. Taken together, our findings show that high levels of NCX over-expression increases neuronal and HEK293 cell survival following OGD, improves calcium management in neuronal cultures and provides additional support for NCX as a therapeutic target to reduce ischemic brain injury.  相似文献   
793.
OBJECTIVE: To determine safe and appropriate alarm limits for the Marquette 8000 pulse oximeter to prevent hyperoxic and hypoxic episodes in neonates. It is necessary to define these limits for each brand of oximeter because of the variance in nonuser adjustable calibration algorithms used in pulse oximeters. METHODOLOGY: Oxygen saturation values obtained from a Marquette 8000 pulse oximeter (SpO2) were compared with simultaneous arterial blood gas PaO2 values obtained from blood gas analysis, for 322 samples in 24 consecutive neonates (median 30 weeks' gestation). RESULTS: In order to prevent 95% of hyperoxic episodes (PaO2 > 90 mmHg), the upper alarm limit was 95% SpO2. Similarly, to prevent 95% of hypoxic episodes (PaO2 < 40 mmHg), the lower alarm limit was 95% SpO2. A sensitivity lower than 95% had to be accepted to develop an alarm range which prevented both hyperoxic and hypoxic episodes. To maintain PaO2 values between 40 and 90 mmHg, an appropriate alarm range of 94-97% SpO2 (90% sensitivity, 28% specificity) was established. CONCLUSIONS: The relative merits of high sensitivity versus high specificity should be considered when determining appropriate alarm limits. Alarm limits which represent a balance between sensitivity and specificity will minimise false alarms and provide a clinically practical range. It would be useful for this type of information to be available for each brand of oximeter, to assist the user in determining appropriate alarm settings.  相似文献   
794.
Helicobacter pylori is accepted as an important factor in the pathogenesis of peptic ulcer disease. Infection is probably most commonly acquired in early life but there is still limited information on the prevalence or symptomatology of H. pylori infection in childhood. The aim of the present study was to establish the prevalence of H. pylori infection in a large sample of urban school children and to determine its relationship, if any, to a history of recurrent abdominal pain. Using a commercial ELISA significant levels of anti- H , pylori IgG antibody were detected in 107/640 (16.7%) of school children (M, 383; F, 257; mean age 9.15 years, range 4-13). No relationship was demonstrated between H. pylori seropositivity and a personal or family history of recurrent abdominal pain or the nature of the pain.  相似文献   
795.
796.

Objective

To evaluate the safety and efficacy of long‐term intraarticular (IA) steroid injections for knee pain related to osteoarthritis (OA).

Methods

In a randomized, double‐blind trial, 68 patients with OA of the knee received IA injections of triamcinolone acetonide 40 mg (34 patients) or saline (34 patients) into the study knee every 3 months for up to 2 years. The primary outcome variable was radiologic progression of joint space narrowing of the injected knee after 2 years. Measurements of minimum joint space width were performed by an automated computerized method on standardized fluoroscopically guided radiographs taken with the patient standing and with the knee in a semiflexed position. The clinical efficacy measure of primary interest was the pain subscale from the Western Ontario and McMaster Universities OA Index (WOMAC). Efficacy measures of secondary interest were the total score on the WOMAC, physician's global assessment, patient's global assessment, patient's assessment of pain, range of motion (ROM) of the affected knee, and 50‐foot walking time. Clinical symptoms were assessed just before each injection.

Results

At the 1‐year and 2‐year followup evaluations, no difference was noted between the two treatment groups with respect to loss of joint space over time. The steroid‐injected knees showed a trend toward greater symptom improvement, especially at 1 year, for the WOMAC pain subscale, night pain, and ROM values (P = 0.05) compared with the saline‐injected knees. Using area under the curve analyses, knee pain and stiffness were significantly improved throughout the 2‐year study by repeated injections of triamcinolone acetonide, but not saline (P < 0.05).

Conclusion

Our findings support the long‐term safety of IA steroid injections for patients with symptomatic knee OA. No deleterious effects of the long‐term administration of IA steroids on the anatomical structure of the knee were noted. Moreover, long‐term treatment of knee OA with repeated steroid injections appears to be clinically effective for the relief of symptoms of the disease.
  相似文献   
797.
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