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51.
52.
Using the transcranial Doppler technique to assess postnatal changes in cerebral blood flow velocity, we studied the anterior cerebral artery, middle cerebral artery, and internal carotid artery of 31 healthy, term newborn infants. Normative values for the 1st, 3rd, and 5th days of life were determined. Cerebral blood flow velocity values in all three arteries examined correlated well with each other and we observed a statistically significant increase only in middle cerebral artery blood flow velocity between the 1st and 3rd, and 1st and 5th postnatal days. Thus, if we assume that flow velocities in various cerebral arteries undergo similar change, only one representative artery need be examined. The middle cerebral artery appears to be the vessel of choice. This choice simplifies the recording procedure, particularly in repeated examinations.  相似文献   
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The purpose of this retrospective investigation is to compare vertical growth component of craniofacial structure of subjects with early and late adenoidectomy history. The study consisted of 93 lateral cephalometric radiographs of three groups of randomly selected patients. The first group was made up of 12 patients (10 male and two female) with an average age of 11.16 +/- 2.08 years, who had been operated upon between 1.5-4 years of age. The second group was made up of 54 patients (25 maleand 29 female) with an average age of 12.18 +/- 2.6 years, who had been operated upon after four years of age. The third group of 27 patients (7 male and 20 female) with clear airway with an average age of 11.18 +/- 2.35 years was used as the control. The data obtained from two adenoidectomy groups were compared and because no statistically significant difference was found except for ANSMe/NMe, the two groups were pooled and compared with the growth pattern in the control sample. There were statistically significant differences in the following parameters: SNGoMe, PPGoMe angle, Gonial angle, Gonial ratio, sigma of inner angles, ANSMe/NMe ratio, Jarabak ratio, PNS-adl distance, PNS-ad2 distance, OAW1 distance. When compared with the control group, the adenoidectomy group showed a more vertically directed growth pattern, however, there were no vertical growth pattern differences between the two groups of children who had adenoidectomy before and after four years of age.  相似文献   
55.
BACKGROUND: The ascending aortic dilatation secondary to aortic valve disease may be a risk for rupture or dissection unless it is not corrected with a graft replacement during valve surgery. This additional procedure requires prolonged operation time that can be harmful for the critical patient. External reinforcement of diseased aorta is an old but simple method with debated long term results, providing brief duration and lower complication rate of the aneurysm operation for critically ill patients whose life expectancy is poor. METHODS: Twenty-two patients underwent aortic valve replacement and external aortic wrapping procedure in our clinic. All of the patients had severe associated risk factors to complicate the classical aortic graft replacement procedure. In this prospective clinical study, the follow-up period of the patients is 79.91 patient-years. RESULTS: There was no operative mortality. The average hospital stay was 8.6+/-2.6 days. There was no late death or cardiac morbidity. All of the patients were in NYHA Class 1 at postoperative 3rd month and thereafter. In CT scans the mean preoperative ascending aortic diameter was 5.12+/-0.38 cm while the mean diameter at 3rd month postoperatively was 3.19+/-0.25 cm. The reduction in diameter showed a significant difference (p<0.0001). The time related changes in luminal diameters showed some enlargement within the first year of the operation (p=0.03) that remained the same thereafter. CONCLUSIONS: The early results and 4 years follow-up suggest that the technique can be regarded as safe and effective in selected high risk patients.  相似文献   
56.
We report a case of suprasellar papillary craniopharyngioma metastatic to the temporoparietal region 2 years after its initial resection. The literature documents examples of craniopharyngioma recurrences along the surgical tract, as well as remote ipsi- and contralateral metastases via cerebrospinal fluid seeding. Ours is the second report of a craniopharyngioma of papillary type to exhibit metastatic behavior. The tumor spread opposite the side of craniotomy. Although a rare occurrence, it confirms the limited capacity of histologically benign craniopharyngiomas to undergo meningeal seeding, likely the result of surgical manipulation. Immunohistochemical demonstration of increased microvascular density and vascular endothelial growth factor expression, as well as a high vascular endothelial growth receptor (VEGFR2) signal by in situ hybridization, suggests that tumor vascularity facilitated angiogenesis and may have been involved in the establishment and growth of the metastatic deposit.  相似文献   
57.
Coronary by-pass on a beating heart may provide a safer form of surgical revascularization by avoiding the well-documented side effects of cardiopulmonary by-pass. In addition, off-pump bypass is suggested to be a good alternative to on-pump especially in high risk patients. This study reviews the feasibility of coronary by-pass on the beating heart in all patients referred to surgery. Two hundred and ninety-four patients operated on the beating heart were prospectively followed and compared to the control group of 100 consecutive patients operated with the conventional method. There were no significant differences between the groups with respect to risk factors, except the incidence of chronic obstructive pulmonary disease and ejection fraction which were higher in the conventional group, whereas peripheral vascular disease was higher in the beating heart group. There was more distal anastomosis in the conventional group. Postoperative inotrope requirement, peak creatine phosphokinase- MB, ventilation time, blood loss in the first 24 h, transfusion needs, new atrial fibrillation and length of hospital stay were significantly lower in the beating heart operations. However, there were no significant differences between the groups in terms of neurological complications, chest infection, intraaortic balloon pump usage and mortality. In conclusion, multivessel off pump coronary by-pass is feasible with the same or better results as it is observed in the conventional technique when postoperative bleeding, neurogenic complications, arrythmias, hospital stay, overall morbidity and mortality are compared.  相似文献   
58.
The primitive trigeminal, otic, hypoglossal, and proatlantal intersegmental arteries are fetal anastomoses between the carotid and vertebrobasilar systems. Persistent trigeminal artery (PTA) is the most frequent embryonic communication between the vertebrobasilar and carotid systems in adults. We report a case of PTA compressing the left side of the pituitary gland and stalk, in a patient with elevated blood prolactin level. Received: 28 February 2000 Revised: 7 June 2000 Accepted: 9 June 2000  相似文献   
59.
Intestinal tuberculosis is a major problem in many regions of the world. The incidence of it is rising in Western countries due to immigration from Third World countries and human immunodeficiency virus infection. The difference between the simple closure and resection and anastomosis was evaluated in this study. Retrospectively, 12 patients with intestinal tuberculosis diagnosed histopathologically among 50 patients with free intestinal perforations operated on between 1995 and 2003 at Turgut Ozal Medical Center were evaluated. Each patient underwent routine laboratory tests and radiologic studies. The most common symptoms of patients were abdominal pain, night sweats, and weight loss. Sites of perforation were ileum in 10 patients (multiple perforation in 4) and jejunum in 2 patients (both had multiple perforations). The perforation was closed by primary closure in 7 patients. Resection-anastomosis was performed in 5 patients. Leaks occurred in overall 3 of 7 patients with primary closure. Three of the 7 patients with leaks due to septicemia died. The mortality rate among all patients was 25%. Intestinal tuberculosis should be kept in mind as a cause in free intestinal perforations. Because of high mortality rate, the resection of the affected area and anastomosis may be the treatment of choice rather than primary closure.  相似文献   
60.
Subaortic stenosis (SAS) is a wide spectrum of anatomical derangements ranging from a discrete fibrous membrane to tortuous fibrous tunnel with or without aortic annulus hypoplasia. We have reviewed 88 patients undergoing surgery for SAS over a 15-year period. There were 47 male and 41 female patients with a mean age of 19.8 +/- 10.6 years (range 11 to 39). Fifty-eight patients had discrete subaortic membrane, and 30 patients had diffuse tunnel subvalvular stenosis. The mean systolic pressure gradients were found to be 86.5 +/- 31.4 mmHg (range 48 to 145 mmHg). Ten patients had mild and 13 patients had moderate-to-severe aortic insufficiency (AI) preoperatively. Nine patients had bicuspid aortic valve. Forty patients (45.4%) had associated cardiac lesions. Isolated membranectomy was performed in six patients. Membranectomy associated with septal myectomy was done in 52 patients. Fifteen patients of them associated hypoplasia of the aortic orifice necessitated aortic valve replacement (AVR) using the Konno-Rastan procedure. Fifteen patients with tunnel SAS and normal aortic valves underwent a combined approach for valve sparing, a modified Konno procedure with patch septoplasty. Also eight patients required AVR because of the severity of AI and five patients aortic reconstruction procedures. Aortic commissurotomy was performed to relief of stenosis in four patients. There were three early deaths (3.4%) and one late death (1.1%) all after the Konno-Rastan procedure. Eight patients (9.1%) had permanent conduction abnormalities. Postoperative left ventricle-aorta gradient was significantly decreased at early postoperative period (p < 0.001) and ranged from 10 to 25 mmHg (mean 14.1 +/- 4.3). Fourteen patients (16.5%) were reoperated for recurrent obstruction or progression of AI. The mean reoperation interval was 4.4 +/- 1.7 years (range 2 to 8 years). Five-year reoperation-free survival was 88.0 +/- 3.6% and 12.5-year reoperation-free survival was 75.5 +/- 7.0%. Our results of aggressive surgical approach of subvalvular aortic stenosis produces relief of obstruction and frees the valve leaflets, significantly reducing associated AI with long-term survival and long-term adequate relief of left ventricular outflow tract obstruction.  相似文献   
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