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41.
OBJECTIVE: A wide range of Doppler threshold values for carotid stenosis is found in the literature. We undertook this study to compare methods of derivation and to determine if an optimum strategy of threshold selection exists for a high-risk population. MATERIALS AND METHODS: From the sonograms of all patent internal carotid arteries, peak systolic velocity in the internal carotid artery (ICA(PSV)) and the ratio of peak systolic velocity in the internal carotid artery to that of the common carotid artery (ICA(PSV)/ CCA(PSV)) were compared with the percentage of angiographically determined stenosis. Receiver operating characteristic curves were generated for levels of stenosis > or =60% and > or =70%. Doppler thresholds were chosen on the basis of maximum accuracy and on the basis of > or =90% sensitivity and specificity. Patients were then segregated into symptomatic and asymptomatic cohorts, and the above process was repeated. An effectiveness analysis was also conducted using various Doppler thresholds. Thresholds derived using these three methods were compared and optimal values chosen. RESULTS. Of 333 carotid arteries that fit inclusion criteria, 132 were found in asymptomatic patients and 201 in symptomatic patients. Maximum accuracy, > or =90% sensitivity and specificity, and effectiveness analysis each produced different ranges of thresholds. We chose final thresholds that maintained patient outcome profiles. For asymptomatic patients at the > or =60% stenosis level, thresholds were ICA(PSV) = 200 cm/sec and ICA(PSV)/CCA(PSV) = 3.0. For symptomatic patients with stenosis > or =70%, thresholds were ICA(PSV) = 175 cm/sec and ICA(PSV)/CCA(PSV) = 2.5. CONCLUSION: Considerable latitude exists in the choice of carotid Doppler thresholds. We propose a rational strategy for threshold selection based on a combination of three commonly used methods. Our observations indicate that it appears advisable to consider symptomatic and asymptomatic patients separately and to apply appropriately derived thresholds.  相似文献   
42.
43.
Microbial investigation of 30 samples of sausage meat and 30 samples of hamburger meat, freshly prepared, were collected randomly from different markets in Alexandria city, to determine the bacteriological status of these products. The average counts/gm of total bacteria, total coliforms and fecal coliform in sausage meat were 1.33 x 10(7), 9.16 x 10(5) and 1.11 x 10(3) respectively, and in hamburger samples were 8.47 x 10(5), 2.63 x 10(3) and 1.35 x 10(3) respectively. Shigella, Escherichia coli, Staphylococcus aureus and Proteus spp were isolated with various percentages, whereas Salmonella spp was isolated from sausage only. The public health importance of the isolated microorganisms are fully discussed.  相似文献   
44.
GABAergic presynaptic inhibition has been investigated in primary afferents using an in vitro preparation of the crayfish, Procambarus clarkii. Presynaptic terminals of a leg proprioceptor, the coxo-basal (CB) chordotonal organ, were impaled in the neuorpil of the 5th thoracic ganglion. Pressure ejection of small volumes of the GABAA or GABAB receptor agonists, muscimol and 3-aminopropylphosphinic acid (3-APA), both induce depolarizing responses in the impaled CB sensory terminal. These depolarizations are not blocked by the specific GABAA and GABAB receptor antagonists, SR-95531 and phaclofen, but they are abolished by picrotoxin. Both muscimol- and 3-APA-induced depolarizations are carried by an increase in conductance to Cl-. The presynaptic increase in conductance to Cl- by GABA receptor activation leads to a depression of sensory synaptic transmission through a shunting of the incoming spikes. Monosynaptic EPSPs elicited in motor neurons by CB sensory nerve stimulation are depressed by muscimol and 3-APA. GABA-mediated presynaptic modulation occurs in crayfish primary afferents which can adjust the gain of reflexes. These results show that GABA-activated Cl- channels can induce a modulation of synaptic transmission, but also that the distinction between GABAA and GABAB receptors, as in vertebrates, is not applicable to the crustacean primary afferents.  相似文献   
45.
This paper deals with the cultural elements of the delusions of a sample of Egyptian psychiatric patients. After examination of clinical records, interviewing psychiatrists and reviewing literature, the author reaches the conclusion that the content of the patient's delusion varies directly in relation to his social class. For most of the low class men and women, the delusional symptoms, either megalomaniac or persecutory were fantasied in terms of the cultural religious institutions. Middle and upper class patients, however, much more frequently "secularized" their restitutive narcissistic and self esteem delusions in terms of science and class conception of power.  相似文献   
46.
47.
Current expansion of the recipient population and increased utilization of left ventricular assist devices as a bridge-to-transplantation have resulted in HLA sensitization becoming an increasingly important clinical problem in cardiac transplantation. We evaluated the impact of HLA sensitization and donor cause of death on survival in 500 cardiac transplant recipients. Donor cause of death was grouped into two categories, trauma and nontrauma. Panel reactive antibodies at the time of transplant were assayed and used as a marker for sensitization if more than 10%. Sensitized recipients had a poorer 1-year survival than those not sensitized (76 vs. 89%, respectively, P=0.2). Donor cause of death had an overall significant impact on survival with 1-year survival for recipients of trauma organs of 92 and 82% for recipients of nontrauma hearts (P=0.02). Trauma hearts transplanted into sensitized recipients yielded a survival of 93% at 1 year whereas if nontrauma donor hearts were transplanted into these recipients, survival was only 52% at 1 year, P<0.001. These intriguing results suggest that graft survival in HLA-sensitized recipients could be significantly improved through the use of hearts from trauma death donors.  相似文献   
48.
Olfactory groove meningioma: surgical techniques and pitfalls   总被引:8,自引:0,他引:8  
  相似文献   
49.
Talic RF  El Tiraifi A  El Faqih SR  Hassan SH  Attassi RA  Abdel-Halim RE 《Urology》2000,55(6):1503-90; discussion 890-1
Objectives. Transurethral vaporization resection of the prostate (TUVRP) is a recent modification of the standard transurethral prostatectomy (TURP). The procedure uses one of the novel, thick resection loops coupled to augmented electrocutting energy. We evaluated the safety and efficacy of TUVRP in comparison with TURP.Methods. Sixty-eight patients with prostatic outflow obstruction were prospectively randomized between equal TUVRP and TURP treatment groups. Safety parameters evaluated included changes in serum hemoglobin, hematocrit, and sodium 1 and 24 hours after resection. Operative time, catheterization time, and incidence of complications were noted. Efficacy parameters included evaluation by the International Prostate Symptom Score and maximum flow rate.Results. Patients of both groups were balanced for the different baseline variables. One hour after TURP, patients had significantly lower levels of hemoglobin, hematocrit, and sodium (P = 0.03, 0.03, and 0.01, respectively). The prostate resection weight was similar in both groups; however, the difference in the mean operative time was significant (TUVRP group 42.4 minutes and TURP group 35.9 minutes, P = 0.02). The postoperative catheterization time was significantly shorter for the TUVRP group (23.1 ± 10.3 versus 36 ± 17.3 hours, P <0.0001). All patients were followed up for an average of 9 months. The International Prostate Symptom Score was 4 ± 3.4 and 5.6 ± 3.1 and the maximum flow rate was 19 ± 6.5 and 15.2 ± 10 mL/s for the TUVRP and TURP groups, respectively; these differences were statistically significant (P = 0.03 and 0.01, respectively). Complications included urethral strictures (6 patients) and delayed hemorrhage with clot retention (2 patients); no differences in the incidence of complications were noted between the two groups.Conclusions. The results of the present study have demonstrated that TUVRP is as safe and efficacious as TURP in the treatment of men with prostatic outflow obstruction. The shorter catheterization time observed after TUVRP may be clinically significant, considering the demand for lower morbidity profiles by patients. The longer operative time in TUVRP was related to the slower motion of the Wing electrode needed to add the advantages of electrovaporization.  相似文献   
50.
Angiocentric lymphoma of the face is a rare malignancy. During 11 years, only two patients were treated for a lymphoma of the face. The first patient, 31-year-old, had an angiocentric lymphoma of the nasal cavity, the second patient, 40-year-old, had an angiocentric lymphoma of the nasopharynx and the maxillary sinuses, with an extension the hard palate. According to the Ann Arbor classification, the disease was stage IEab and stage IIEbb, respectively. The first patient was treated by chemotherapy alone (COP regimen) and the second patient underwent combined chemotherapy (CHOP) and radiotherapy. The follow-up was marked by progression of the disease 7 and 9 months after the end of the treatment in the two cases. For the angiocentric lymphoma, treatment based on radiotherapy or chemotherapy alone or combined does not often provide local control and the overall survival rate does not exceed 40% at 5 years.  相似文献   
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