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91.
Among the 1,892 patients who underwent cerebrovascular digital subtraction angiography at our hospital over the past 18 months, there was a subgroup of 34 patients (65 carotid arteries) for whom noninvasive cerebrovascular test results and standard cerebral arteriograms were also available. These patients were reviewed retrospectively and the ability of both methods to detect hemodynamically significant lesions, defined as a greater than 50 percent reduction in the diameter of the carotid artery, was determined using the arteriograms as the "gold standard." Noninvasive cerebrovascular tests had a sensitivity of 81 percent, a specificity of 95 percent, a positive predictive value of 92 percent, a negative prediction value of 88 percent, and an overall accuracy of 89 percent. Digital subtraction angiography had a sensitivity of 84 percent, a specificity of 92 percent, a positive predictive value of 88 percent, a negative predictive value of 89 percent, and an overall accuracy of 89 percent. If the four cases of hemodynamically significant stenosis of the carotid siphon not detected by digital subtraction angiography had been considered as false-negatives, its sensitivity would have been reduced to 72 percent. In patients with hemispheric cerebral ischemia, we found noninvasive cerebrovascular tests neither necessary nor cost-effective. Digital subtraction angiography, on the other hand, often provided definitive diagnostic information in such patients if the intracranial circulation was well defined and the extracranial lesion corresponded to the patients' symptoms. Noninvasive cerebrovascular testing was the safest and most cost-effective technique for screening patients with asymptomatic bruits, atypical, nonhemispheric cerebral symptoms, and those who have undergone carotid endarterectomy. If the noninvasive cerebrovascular test result was positive or equivocal, digital subtraction angiography was performed to localize the responsible lesion and exclude carotid occlusion. 相似文献
92.
Recent work has shown that vasoactive intestinal peptide (VIP), one of the many candidate hormones of the gut, also occurs widely in neurones. To determine whether the neuronal peptide may have a neurotransmitter function, we studied changes in immunoreactive VIP in dog plasma and human cerebrospinal fluid after the infusion of choline esterase inhibitors (neostigmine and physostigmine, respectively). Immunoreactive VIP was released in both situations. The systemic changes (in VIP levels) were enhanced five weeks after portacaval shunting in dogs. Our results demonstrate that the immunoreactive VIP level increases as a result of choline esterase inhibitors. The plasma "release" may originate either from peripheral peptidinergic nerve terminals or from APUD cells of the gastroenteropancreatic system. The increase in immunoreactive cerebrospinal fluid VIP may very well originate from central neurons, since the peptide does not apparently cross the blood-brain barrier. 相似文献
93.
Despite immediate operation, patients with abdominal aortic injuries and profound hypovolemic shock do not respond to the usual methods of resuscitation and die soon after celiotomy, prior to control and repair of the aortic injury. The rate of aortic hemorrhage exceeds the ability to restore blood volume. Shock becomes "irreversible." In such patients tamponade of the aortic injury may be effected by the use of an external counterpressure device such as a G-suit or MAST suit. These devices, used in conjunction with transthoracic aortic occlusion, may raise blood pressure sufficiently to perfuse the sritical coronary and cerebral circulation, allowing time to correct acidosis and locate, control, and repair the aortic injury. Early aggressive therapy should result in increased survival. 相似文献
94.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis. 相似文献
95.
Hemodialysis in elderly patients 总被引:1,自引:0,他引:1
Brown WW 《International urology and nephrology》2000,32(1):127-135
International Urology and Nephrology - 相似文献
96.
电子病历书写的质量管理与对策 总被引:4,自引:0,他引:4
侯微 《国际医药卫生导报》2004,10(18):243-244
目的 探讨和总结电子病历(Eleetronic Medical Record,EMR)使用中医生记录的质量控制方法。方法 对EMR中医生记录进行质量分析,找出存在的常见主观性和客观性错误,采用软件设计与建立管理制度的方法提高质量。结果 通过改进软件设计和建立健全规章制度可以达到EMR质量控制。 相似文献
98.
Murakami T Kikugawa D Endou K Fukuhiro Y Ishida A Morita I Masaki H Inada H Fujiwara T 《Artificial organs》2000,24(12):953-958
In this study, we analyzed the extent and pattern of regression of left ventricular (LV) hypertrophy after aortic valve replacement in patients with aortic stenosis (AS) and compared the results with those of another group of patients with aortic regurgitation (AR). Seventy patients who underwent isolated aortic valve replacement were divided into 2 groups. Group 1 was comprised of 29 patients who underwent aortic valve replacement for aortic stenosis, and Group 2 of 41 patients who underwent aortic valve replacement for aortic regurgitation. A third group of 10 healthy subjects served as a healthy control group. Echocardiographic studies were done before the operation and 5 years postoperatively. At follow-up, a significant reduction in the left ventricular mass was found in both groups, but it remained significantly greater than in the healthy control group. The ratio of LV wall thickness to radius (th/r) in Group 1 decreased significantly, and at follow-up it was within the normal value. In Group 2, the th/r ratio increased, and at follow-up it was within the normal value. After aortic valve replacement, the wall thickness remained significantly greater than normal for patients with AS, and the chamber radius remained significantly greater than normal for patients with AR. For these reasons, LV hypertrophy still existed in both groups at postoperative follow-up. The actuarial survival rate was 85.3% at 16 years for Group 1 and 83.4% at 18 years for Group 2. There was no significant difference in the long-term survival rates between the 2 groups. Actuarial freedom from valve-related events was 91.9% at 16 years for Group 1 and 82% at 18 years for Group 2. There was no significant difference in the valve-related event free curves between groups. After 5 years of follow-up, th/r reached normal for both groups, indicating remodeling of the LV geometry after aortic valve replacement. 相似文献
99.
The aim of this study was to elucidate undergraduate university students' views on clinical xenotransplantation. A total of 1875 students from eight faculties at Uppsala University and the Swedish University of Agricultural Sciences answered a questionnaire. Three out of four respondents would be prepared to receive a transplant from an animal on medical grounds if necessary. Forty percent had signed an organ donation card. There was no difference in attitude between those who had signed an allotransplantion card and those who had not. According to gender, age, length of university program, and faculty, results showed that a higher proportion of those who approved were male, young, and studying on programs longer than three years; also, they were more likely to study programs in the Faculties of Agriculture and Pharmacy. At the Medical Faculty, nursing students seemed to be less approving, compared to future biomedical analysts, biomedical scientists, and physicians. The acceptance of xenotransplantation also tended to be positively associated with morally accepting and understanding the use of animals in biomedical research, the approval of euthanasia, the approval of early abortion, and the use of human fetuses in research, as well as clinical testing of humans. 相似文献
100.
John A. Enbom MD Claire D. Thomas MS MBA 《American journal of obstetrics and gynecology》1997,176(6):1340-1348
OBJECTIVE: In 1991 the Oregon Board of Medical Examiners initiated a separate category for the complaint of sexual misconduct. Investigated complaints of sexual misconduct brought to the Oregon Board of Medical Examiners were analyzed for the years 1991 to 1995 to serve as a baseline. Comparison was made to the Federation of State Medical Boards sexual misconduct data for 1991 and 1992.STUDY DESIGN: One hundred complaints brought against 80 licensees were evaluated by practitioner's degree, age group, sex, specialty, and disposition of complaints for the years 1991 to 1995. The allegations were classified into behavior categories of sexual impropriety, sexual transgression, and sexual violations.RESULTS: Sexual misconduct was the allegation in 5.9% of the complaints investigated for the study period. Oregon had more sexual misconduct complaints than the average reported to the Federation of State Medical Boards for the years 1991 and 1992. Most (72%) complaints came from the patients or their families. Two female physicians (2.4%) had sexual boundary complaints. Sexual misconduct complaints increased by a risk ratio of 1.44 with advancing age by decades. Allegations classified into behavior categories according to severity revealed 39% sexual impropriety, 31% sexual transgression, and 30% sexual violation. Reportable disciplinary actions occurred only with multiple allegations of sexual impropriety (6.5%) and for sexual transgression (27%) whereas sexual violation allegations often had one complainant but there were 54% reportable disciplinary actions. Family practice, obstetrics and gynecology, and psychiatry had the highest incidence of sexual misconduct complaints whereas psychiatry and obstetrics and gynecology had the highest incidence of reportable disciplinary actions. Twenty-five percent of the closed cases resulted in reportable disciplinary actions. This analysis is discussed in relationship to legal and ethical issues and the goal of zero tolerance.CONCLUSIONS: Oregon has a higher percentage of sexual misconduct complaints than the average for 42 states reporting to the Federation of State Medical Boards for the years 1991 and 1992. Analysis of the Oregon Board's experience for the study years will provide a baseline for future evaluation and as an educational resource for the Oregon Board of Medical Examiners and professional and specialty societies. Ethical standards, the reporting and investigative processes, and the legal framework are in place and lessen the incidence of sexual misconduct and work toward zero tolerance. (Am J Obstet Gynecol 1997;176:1340-8.) 相似文献