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1.
Objective: Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions. Methods: An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test. Results: The mean horizontal distances in the 10 specimens were 19.5 ± 1.8 mm by microscope and 27.5 ± 2.2 mm by endoscope, and the mean vertical distances were 25.8 ± 1.9 mm by the microscope and 34.5 ± 3.5 mm by the endoscope. Conclusion: The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery.  相似文献   
2.
Background: The aim of this study was to investigate the postoperative hemodynamic effects of nitroglycerin inhalation on patients with pulmonary hypertension undergoing mitral valve replacement surgery.

Methods: Twenty patients who underwent mitral valve replacement surgery were included in the study. In the surgical intensive care unit, at T0 (before the inhalation of nitroglycerin), basal systemic and pulmonary hemodynamics were recorded. Then, 2.5 [mu]g [middle dot] kg-1 [middle dot] min-1 nitroglycerin liquid nebulized by a 2-l gas flow of 40% oxygen and air mixture was administered to the patients who were diagnosed as having pulmonary hypertension (mean pulmonary arterial pressures > 25 mmHg). The same parameters were measured at the first (T1), third (T2), and fifth (T3) hours after the beginning of this treatment and 1 h after the end of nitroglycerin inhalation (T4).

Results: There were no statistically significant differences at T0, T1, T2, T3, or T4 with respect to heart rate, mean arterial pressure, systemic vascular resistance, cardiac index, mixed venous oxygen saturation, arteriovenous oxygen content difference, or arterial carbon dioxide tension. However, mean pulmonary artery pressure, pulmonary vascular resistance, and intrapulmonary shunt fraction were significantly lower, and the arterial oxygen tension/fraction of inspired oxygen ratio was higher at T1, T2, and T3 when compared to that of T0 and T4.  相似文献   

3.
OBJECTIVE: Calcium channel blockers are commonly used in some cardiovascular disorders. These drugs can act at neuromuscular transmission, at both pre- and postsynaptic levels and may produce neuromuscular dysfunction. Therefore, they may result in misdiagnosis in electrophysiological testing of healthy subjects. This study aimed to investigate the influence of calcium channel blockers on neuromuscular transmission, using single fiber electromyography, in subjects who were healthy excepting controlled arterial hypertension condition. METHODS: Single fiber electromyography during voluntary contraction of the extensor digitorum communis muscle, nerve conduction studies of upper and lower extremities, and concentric needle electromyography of the extensor digitorum communis were performed on 16 verapamil users, 16 amlodipine users, and 16 age-matched normal controls. Twenty potential pairs were recorded from each subject. Twenty individual jitter values and a mean jitter value were calculated for each subject. Both mean jitter values and numbers of abnormal individual jitter values were compared in verapamil and amlodipine users versus normal controls. RESULTS: Eight of 16 verapamil users and 7 of amlodipine users showed evident neuromuscular transmission abnormalities by single fiber electromyography. Two subjects from verapamil and one subjects from amlodipine users group had borderline dysfunction of neuromuscular transmission. CONCLUSIONS: These results suggest that both verapamil and amlodipine impair neuromuscular transmission in subjects without neuromuscular disease. SIGNIFICANCE: The effects of verapamil and amlodipine are at a level, which may cause misinterpretation of single fiber electromyography studies carried out to investigate neuromuscular junction disorders.  相似文献   
4.
The Harmonized Alert Sensing Technology (HASTE) device was developed to overcome the primary shortcomings of interval based noninvasive blood pressure (BP) monitoring. This study was conducted to assess the reliability of the HASTE system compared with standard cuff BP values in patients on hemodialysis. A total of 1,370 HASTE measurements were compared with oscillometric standard cuff systolic BP values in 42 sessions of 15 patients on hemodialysis. The average discrepancy between the HASTE and cuff systolic BP was 1.41 +/- 16.90 mm Hg. Compared with cuff measurements, 31% of systolic BP fell within a range of 5 mm Hg difference, 57% of systolic BP fell within 10 mm Hg, and 73% of systolic BP fell within a 15 mm Hg band. According to British Hypertension Society standards or Association for the Advancement of Medical Instrumentation criteria, the current HASTE method did not perform well. Technology to provide noninvasive hemodynamic monitoring is, however, in its developmental stage. The effort at continuous systolic pressure monitoring using existing, readily available, and frequently used techniques is exciting. Although the HASTE system as currently configured and calibrated did not adequately perform, variations in site analysis and conversion factors may increase pressure sensitivity and tracking over the course of a standard dialysis treatment.  相似文献   
5.
To compare retrospectively the recurrence rates of TUR alone versus different intravesical chemotherapy modalities in superficial bladder cancer cases, 187 patients with stage Ta and T1 bladder tumours were treated with transurethral resection followed by adjuvant intravesical chemotherapy with mitomycin, BCG or epirubicin or by transurethral resection alone. All patients in this study had historically proven transurethrally resectable primary, category Ta and T1 transitional cell carcinoma (TCC) of the bladder. Group I included transurethral resection alone, and the other groups included intravesical mitomycin-C(Group II), BCG (Group III) and epirubicin (Group IV) therapies after transurethral resection. 146 male and 41 female patients (78% male and 22% female patients) in this study were diagnosed as primary TCC bladder tumours. Only 52 of them were stage Ta and 135 of them were stage T1 bladder tumours. Examining the histological grade of the bladder tumours, 88 (47%) of the patients had grade I, 53 (28%) had grade IIa, 30 (16%) had grade IIb and remaining 16 (9%) had grade III bladder cancers. The recurrence rates were 25% for Group I, 23.8% for Group II, 26.2% for Group III and 22.7% for Group IV. These values were given with disregarding the grade and volume of the bladder tumours. For solitary, less than 3 cm low grade tumours (grade I, IIa) recurrence rates were 16% for Group I, 15.4% for Group II, 17.8% for Group III, 17.2% for Group IV (p> 0.05). As a result of this retrospective study, for patients with low grade, stage Ta and T1 tumours TUR alone may be the best treatment modality. Although intravesical chemotherapy is effective in decreasing short-term incidences of tumour recurrence, it has not decreased long-term incidences of tumour recurrence. The high cost and adverse side effects of intravesical chemotherapy should also be taken into consideration in superficial, single, low grade tumours of bladder. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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The fact thatH. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whetherH. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients withH. pylori gastritis before and one month after the eradication therapy and also in 15H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients withH. pylori gastritis before the eradication were significantly (P<0.05) higher than those in theH. pylori-negative controls. After the eradication ofH. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P<0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P<0.001). These results suggest thatH. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.Presented in part as an abstract at the 8th Balkan Congress of Endocrinology, Bursa, Turkey, May 3–5, 1995.  相似文献   
9.

Purpose

The aim of our study is to research the role and efficacy of cerebral oximetry in predicting neurologic prognosis when applied during TTM to patients experiencing coma after CA.

Methods

This study was performed on surviving adult comatose patients after CA treated with TTM. The average scores of rSO2 was measured at 6 h intervals for the first 2 days and once a day for the following 3 days with a NIRS device during TTM. The CPC scale was used to define the neurologic outcomes of patients. We compared the correlations of rSO2 values between good (CPC 1–2) and poor (CPC 3–5) neurologic outcomes in CA patients.

Results

There was no statistically significant difference identified between the prognosis groups in terms of rSO2, CPR durations, hemoglobin values and admission body temperature (p > 0.05). When the variation in rSO2 values over time is investigated, though there was no significant difference between the good and poor prognosis groups, it appeared to fall in the first 6 h in both prognosis groups. The median NT-proBNP and lactate values were observed to be higher in the poor prognosis group.

Conclusion

There is no significant correlation between rSO2 values and neurologic outcomes. Multimodal monitoring methods may be useful and further studies with a larger patient population are necessary in this area.  相似文献   
10.
In some countries, Hydatidosis is a common public health problem but cardiac hydatid cysts are rarely observed. The evaluations of operative results and follow up of cardiac hydatid cases. Twenty-five consecutive unselected patients suffering from cardiac hydatidosis and operated on between 1967 and 2006 in Siyami Ersek Cardiothoracic and Vascular Surgery Center were retrospectively analyzed. In 10 of these patients the hydatid cyst was intracardiac, while in 13 patients cysts were extracavitary but located into the pericardium. In 2 patients the hydatid cyst was both intra and extracavitary. Mean age of the patients was 31+/-9.2. The female/male ratio was 17/8. The 12 patients with intracavitary and 2 patients wit extracavitary hydatid cysts were operated on with the aid of extracorporeal circulation. One patient died postoperatively. In one patient recurrence of the hydatidosis was observed. The majority of cases in previous publications were located in the left side of the heart. In our series, most were located in the right heart. In such cases clamping the pulmonary artery is mandatory to prevent pulmonary migration. Careful resection is important for prevention of recurrence.  相似文献   
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