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1.
The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders.  相似文献   
2.
Summary The effect of dexfenfluramine (dF) on body weight, blood pressure and noradrenergic activity were studied in 30 obese hypertensive patients randomly divided into two groups and treated for 3 months either with dF (30 mg daily; 16 subjects) or placebo (Pl; 14 subjects). 11 patients from the dF group and 9 patients given Pl completed the entire experimental protocol, including monthly visits for metabolic and hormonal measurements, as well as a bicycle exercise test with arterial catheterisation for haemodynamic and catecholamine measurements performed before and after 3 months of treatment.A progressive significant decrease in body weight, averaging 6.0 kg after 3 months was observed in the dF-treated group, whereas loss of weight in the placebo group (1.4 kg) was not significant. While blood pressure and noradrenergic activity, assessed as changes in the plasma levels and urinary excretion of norepinephrine, remained unaffected in the Pl group, a significant drop in the supine systolic and diastolic blood pressures, as well as in the resting venous norepinephrine level and in urinary norepinephrine excretion was found after the first month of dF administration. In addition, the exercise-induced rise in systolic and diastolic blood pressure, as well as in arterial plasma norepinephrine and epinephrine concentrations, was significantly reduced after 3 months of dF administration; there were no such changes in the Pl-treated group.The results of the present study indicate that, in addition to the weight-reducing effect of dexfenfluramine, its hypotensive effect may be mediated by a decrease in noradrenergic activity.  相似文献   
3.

Background  

A total of 137 consecutive patients with recent uncomplicated myocardial infarction (n=31) or unstable angina (n=106) were studied to determine the relative prognostic value of predischarge clinical risk stratification and intravenous dipyridamole stress sestamibi (MIBI) myocardial tomography in patients unable to exercise maximally after an acute ischemic coronary event.  相似文献   
4.
PURPOSE: To present a complex case involving an infected carotid-carotid bypass graft that was successfully treated with a stent-graft and subsequent surgical removal of the infected graft. CASE REPORT: A 75-year-old woman presented with persistent purulent drainage of an infected and exposed carotid-carotid prosthetic bypass graft. Wound cultures revealed methicillin-resistant Staphylococcus aureus. She was treated with appropriate intravenous antibiotic therapy without improvement in wound drainage. Because of her comorbid conditions, a decision was made to pursue endovascular revascularization of her left and right common carotid arteries (CCA), with subsequent surgical removal of the infected prosthetic graft. The patient underwent balloon angioplasty; a 7x18-mm Omnilink stent was deployed in the innominate artery and a 7x18-mm Herculink stent in the ostial left CCA. During the same procedure, the carotid-carotid bypass graft was excluded with deployment of an 8x50-mm Viabahn stent-graft in the right CCA. Several days later, the infected and now thrombosed carotid-carotid bypass graft was surgically removed, and an area of adjacent muscle was used to patch the previously excluded connection of the bypass from the right CCA. A saphenous vein patch was used to repair the defect in the left CCA. Her postoperative course was uneventful. At 1 year, the clinical and duplex examinations revealed satisfactory wound healing and patent left and right CCAs. CONCLUSION: This case indicates that a combined endovascular and surgical approach may be a safe and effective option in the treatment of carotid-carotid bypass graft infection.  相似文献   
5.
30余种氨基酸、40余种非挥发性有机酸和20余种碱基核苷类化合物在一块薄层板上完成多相同步色谱分析;用紫外灯-吖啶试剂-镉茚三酮试剂实行组合显色定位分析。改善了尿液中非挥发性有机酸的溶剂萃取法,尿中三类化合物提取物的同步多相色谱分离效果良好。  相似文献   
6.
Genetic polymorphism in the ABO blood group gene of Han, Kazak and Uygur populations inhabiting the most northwestern part of China was investigated using polymerase chain reaction-based techniques. The present study enrolled 43 healthy unrelated Han, 37 Kazak and 59 Uygur volunteers. The allele in A1 blood group is distinguished A0101 and A0102 in difference of nucleotide position 467. The A0101 allele is more frequent in Caucasian and the A0102 allele is characteristic in Mongoloid. It must be notable that A0201 in the A2 group (with a single base deletion at nucleotides 1059 to 1061) which was characteristic of Caucasian was observed in Kazak and Uygur populations but not in Han. Further, 00201 (with no nucleotide deletion at 261 and three nucleotide differences), which is frequent in different races including Caucasian except for Mongoloid, was detected also in Kazak and Uygur populations. The frequencies of B0101 in Kazak, Uygur and Han were comparable to those of other Asian populations but higher than those of Caucasian populations. Collectively, these results reveal that the allele frequencies of Kazak and Uygur at the ABO blood group locus are an intermediate between those of Mongoloid and Caucasian, suggesting the admixed feature of Kazak and Uygur with Mongoloid and Caucasian.  相似文献   
7.
The effect of growth hormone addition to human menopausal gonadotrophin(HMG), after pituitary down-regulation, on granulosa cell function,in in-vitro fertilization (IVF) was evaluated. Growth hormoneor placebo were added in a prospective, randomized and double-blindmanner to an existing IVF stimulation protocol. Forty-two normalovulatory women (38 years old) with mechanical factor infertilityand normal male factor were included in the study. Gonadotrophin-releasinghormone agonist (GnRHa) was given from day 21 of the previouscycle until human chorionic gonadotrophin (HCG) administration.Follicular stimulation with HMG was started after pituitarydown-regulation. Growth hormone 12 IU/day or placebo were administeredon alternate days, beginning day 1 until day 7 of HMG treatment.Granulosa cell function was evaluated, in all patients, by follicularfluid levels of ovarian steroids and insulin-like growth factor-I(IGF-I). In 14 patients, chosen arbitrarily granulosa luteincells were cultured in the presence and absence of additionalHCG. Follicular fluid levels of oestradiol, progesterone, testosteroneand IGF-I were similar in both growth hormone and placebo groups.Basal and post-HCG levels of oestradiol and progesterone didnot differ significantly between the two groups of granulosalutein cell cultures. We conclude that after pituitary down-regulation,in-vivo administration of growth hormone with HMG in young ovulatorywomen does not seem to affect granulosa cell function when comparedto the administration of HMG alone.  相似文献   
8.
BackgroundHolmium laser enucleation of the prostate (HoLEP) has been a widely utilized minimally invasive surgical procedure for benign prostate hyperplasia. The current study aimed to compare surgical outcomes and King’s Health Questionnaire (KHQ) assessment scores following HoLEP between younger men and those aged ≥75 years.MethodsThis prospective single-center study compared perioperative complications, postoperative urinary conditions, and KHQ scores (nine categories) between men aged ≥75 years (group A) and men aged <75 years (group B) before and 1, 3, and 6 months after surgery.ResultsA total of 100 patients were included for analysis (group A, n=38 and group B, n=62). No differences in patient backgrounds, perioperative complications, such as perioperative decrease in hemoglobin, postoperative fever, postoperative indwelling catheterization duration, or postoperative hospitalization duration, and KHQ were observed between both groups. Both groups showed significantly better International Prostate Symptom Scores, quality of life, maximum urinary flow rate, and postvoid residual volume 1, 3, and 6 months after HoLEP compared to their respective preoperative levels (P<0.01). Regarding KHQ categories, both groups showed significantly better general health perceptions, impact on life, emotions, and sleep/energy 1 month after HoLEP; role limitations, physical limitations, and social limitations 3 months after HoLEP; and personal relationships and incontinence severity measures 6 months after HoLEP compared to their respective preoperative levels (P<0.05).ConclusionsHoLEP could be safe and effective even for men aged ≥75 years, comparing complications, urinary condition, and KHQ scores.  相似文献   
9.
Younis M  Vivian A  Lee JP 《Strabismus》1995,3(2):85-88
Background: The Fells modification of the Harada-lto procedure is usually performed bilaterally for the correction of excyclotorsion secondary to acquired bilateral superior oblique paresis. Excyclotorsion is not usually a major complaint in true unilateral superior oblique paresis. Occasional cases, however, may find this symptom bothersome and it may interfere with fusion. The purpose of the present study is to determine the effect of the unilateral modified Harada-lto procedure on the correction of symptomatic excyclotorsion in unilateral superior oblique paresis. Method: A retrospective case-note review of patients with unilateral superior oblique paresis undergoing unilateral modified Harada-lto procedures during the five-year period 1988-1993 was performed. Results: Six patients fulfilled the inclusion criteria. Superior oblique paresis was congenital in one case, secondary to trauma in two cases and idiopathic acquired in three cases. There were four males and two females aged from 25 to 63 years and all but one had previous surgery. The mean pre-operative excyclotorsion was approximately 10 degrees (range 8-14 degrees). Mean post-operative excyclotorsion was 3 degrees (range 2 degrees incyclotorsion -10 degrees excyclotorsion). Conclusion: The unilateral modified Harada-lto procedure is an effective surgical treatment of excyclotorsion resulting from superior oblique paresis and may improve sensory and motor fusion.  相似文献   
10.
Fifty four patients presenting by huge splenomegaly were admitted to Tropical Medicine Department, El-Minia University Hospital. Tissue biopsy revealed pure bilharziasis due to S. hematobium in 10 (19%) cases, liver cirrhosis in 23 (42%), mixed schistosomiasis and cirrhosis in 8 (15%), hepatoma in 3 (6%), lymphoma in 6 (11%) and hematological diseases in the form of chronic myeloid leukemia in 2 (3.5%) and thalassemia major in 2 (3.5%) cases. The sensitivity and specificity of abdominal ultrasonography was 100% and 97% in cases of schistosomiasis, 100% and 100% in cases of hepatoma, 87% and 100% in cases of liver cirrhosis, 33% and 100% in cases of lymphoma respectively. There was a positive significant correlation between endoscopic variceal grading, portal vein diameter, splenic vein diameter, size of the spleen and the grading of the portal tract thickenings. The pathological and ultrasonographic diagnosis was the same in 38 (70%) cases. Splenogram was characteristic but not diagnostic in cases of schistosomiasis and liver cirrhosis. It was diagnostic and similar to peripheral blood picture in the 2 cases of chronic myeloid leukemia and was normal in cases of thalassemia major. Splenic aspiration was able to diagnose all cases of lymphomas. It can be considered as a useful adjunct to the usual diagnostic procedures, both in staging and follow up, especially in cases presenting only by splenomegaly.  相似文献   
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