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41.
微乳液反应法制备磺胺嘧啶银均匀微晶及其质量评价 总被引:1,自引:0,他引:1
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,并评价其质量。方法:利用磺胺嘧啶钠微乳和硝酸银微乳混合后反应的方法,制备磺胺嘧啶银均匀微晶,用透射电镜观察其形态和大小,以X-射线衍射分析、红外光谱、核磁共振、差热分析等手段检测磺胺嘧啶银均匀微晶各种理化特性。结果:磺胺嘧啶银均匀微晶的粒径大小约为2~4μm,均匀微晶的结晶性好,纯度高。体外抑菌实验表明该品比市售磺胺嘧啶银具有更好的抑菌效果。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
42.
OBJECTIVE: Nationwide data were collected concerning serious, disabling injuries requiring hospitalization (SDIH) or deaths among urban emergency medical services (EMS) providers. DESIGN AND SETTING: A mail survey of EMS systems was conducted among the 200 most populated U.S. cities. PARTICIPANTS: Participants were training and operations officers of urban EMS systems. MEASUREMENTS AND MAIN RESULTS: Ninety forms (45%) were returned with 88 evaluable (44%). There were 81 SDIHs for a rate of one in 31,616 dispatches. No deaths were reported. Body parts most frequently injured were the hand (22%), head (19%), foot (16%), and eye (14%). Although 90% of fire-based EMS systems (fire-EMS) provided helmets, eye protection, safety shoes, and gloves, less than half (45%) of nonfire-EMS did so. Three (4%) SDIHs resulted from acts of violence. CONCLUSION: Occupational injuries of EMS personnel are at a serious level. Fire-based EMS systems experienced a higher rate of hand SDIHs despite the provision of protective equipment. Few nonfire-EMS staff are provided with safety equipment, which may have resulted in a relatively high number of head and hand SDIHs. Fire-EMS medical directors need to take an active role in verifying that protective equipment is adequate and appropriate to allow the performance of field EMS duties without being too cumbersome. Medical directors of nonfire-EMS must be advocates for the provision of basic protective equipment aimed at mitigating SDIHs of EMS staff. 相似文献
43.
Effects of diabetes mellitus on the biomechanical properties of human ankle cartilage 总被引:3,自引:0,他引:3
Athanasiou KA Fleischli JG Bosma J Laughlin TJ Zhu CF Agrawal CM Lavery LA 《Clinical orthopaedics and related research》1999,(368):182-189
Metabolic changes attributable to diabetes mellitus affect numerous organ systems in the body. For example, patients with diabetes have an increased number of musculoskeletal injuries and afflictions compared with patients without diabetes and experience more morbidity associated with injury and treatment. Although diabetes also may afflict articular cartilage, no studies have shown a conclusive link between diabetes and cartilage structural integrity. The objective of this study was to obtain and compare the intrinsic material properties of human ankle articular cartilage from patients with diabetes and those without diabetes. These biomechanical properties (aggregate modulus, Poisson's ratio, shear modulus, and permeability) were found to differ significantly between specimens from patients with diabetes and patients without diabetes. Specifically, cartilage from patients with diabetes was significantly softer and more permeable than cartilage from control subjects. For example, in the central portion of the talus, cartilage from patients with diabetes had a 38% smaller aggregate modulus, 37% smaller shear modulus, and 111% larger permeability than did tissue from patients without diabetes. These results provide evidence that joint pathologic processes in patients with diabetes may be associated with compromised structural integrity of articular cartilage. 相似文献
44.
Martino K Merrit S Boyakye K Sernas T Koller C Hauser CJ Lavery R Livingston DH 《The Journal of trauma》1999,46(3):369-71; discussion 372-3
45.
Clostridium difficile colitis in the critically Ill 总被引:1,自引:1,他引:0
S. Grundfest-Broniatowski M.D. M. Quader M.D. F. Alexander M.D. R. M. Walsh M.D. I. Lavery M.D. J. Milsom M.D. 《Diseases of the colon and rectum》1996,39(6):619-623
Morbidity and treatment of
Clostridium difficile
colitis (CDC) continue to be controversial. Some claim minimum morbidity, which may be a function of differences in patient population and/or bacterial virulence. METHODS: To evaluate the effect of CDC in the critically ill, we retrospectively reviewed the records of 59 intensive care unit patients with CDC who were diagnosed by fecal toxin assays or clinical evidence of pseudomembranous colitis from January 1991 to October 1994. Symptoms, signs, antibiotic regimens, diagnostic tests, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, morbidity, and mortality were analyzed, and results of surgical treatment were compared with the literature. RESULTS: Mean age was 66.4 (17–95) years, with a male to female ratio of 1.81. First treatment was metronidazole by mouth in 15 patients (25.4 percent), vancomycin by mouth in 30 patients (50.8 percent), sequential by mouth vancomycin/metronidazole in 3 patients (5.1 percent), and intravenous metronidazole in 5 patients (8.5 percent). Six patients had no medical therapy before surgery or discharge. Ten patients (17 percent) had recurrence and 12 (20.3 percent) required surgery for progressive toxicity or peritonitis. Of three patients who were initially treated by diverting stomas, one died and two required total colectomy (TAC). Two underwent partial resection (1 that was nearly a total colectomy), and seven others had a TAC. Surgical patients had worse mean APACHE II scores at diagnosis (24.4
vs.
199;P<0.001). Thirty-day mortality in surgical patients was 41.7
vs.
14.7 percent in medical patients (P<0.5).CONLUSION: Twenty percent of critically ill patients with CDC required operation. TAC and diversion appeared to be more effective surgical treatments than diversion alone.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Montreal, Quebec, Canada, May 7 to 12, 1995. 相似文献
46.
STUDY OBJECTIVE: Blood pressure (BP) in the out-of-hospital setting is one of the most important diagnostic tools used by emergency medical services (EMS) providers. Conventional methods of palpation and auscultation can be time consuming, and the measurements often are inaccurate because of the adverse working conditions encountered. Pulse oximetry waveform systolic blood pressure (POWSBP) measurement has been used successfully in emergency departments to monitor BP. The objective of this study was to compare the accuracy of field POWSBP measurements obtained by noninvasive electronic BP measurement (NIBPM), auscultation, and palpation in the out-of-hospital environment. DESIGN: Blood pressure measurements used for this study were obtained by POWSBP, NIBPM (PROPAQ model 102; Protocol Systems, Beaverton, Oregon USA), auscultation, and palpation on patients in moving ambulances. Measurement of POWSBP was accomplished by observing the return of the waveform on the pulse oximeter at the time of cuff deflation. The order in which the readings were obtained as well as the arm chosen for measurement were randomized. SETTING AND PARTICIPANTS: Paramedics and emergency medical technicians in an urban, inner-city emergency medical services (EMS) system. MEASUREMENTS AND MAIN RESULTS: Blood pressure measurements were sampled from 69 patients. Regression analysis identified significant correlation between POWSBP and the four methods utilized, with r = 0.92 for NIPBM, r = 0.95 for auscultation, and r = 0.97 for palpation, all significant at p < 0.0001. CONCLUSIONS: The use of POWSBP measurement is a fast, easy, and accurate technique with which to measure systolic BP in the field. It may have special importance for noisy environments and moving vehicles in which conventional methods of auscultation or palpation may be difficult. 相似文献
47.
INTRODUCTION: There is a paucity of data comparing injured pediatric patients transported by helicopter emergency medical services (HEMS) with patients transported by ground ambulance. The purpose of this study was to compare HEMS pediatric trauma patients to: 1) pediatric patients transported by ground to an urban level-1 trauma center (TC), and; 2) a similar cohort of adult patients. The managed-care consequences of these comparisons are highlighted. METHODS: All trauma patients flown directly from the scene by HEMS from January 1, 1990, to April 30, 1993, were compared to a cohort of trauma patients arriving by ground advanced life support (ALS). All patients were transported to the same level-1 TC. The data collected included the mechanism of injury and the prehospital procedures performed, the injury severity score (ISS), and outcome. RESULTS: There was no difference in the ISS between the HEMS (n = 216) and ground ALS (n = 355) pediatric patients (16.8 vs 17.1; p = 0.55). Adult HEMS patients (n = 202) had significantly higher ISS than did injured adults (n = 1652) transported by ground (18.0 vs 13.6; p < 0.0001). Overall, trauma patients transported by air directly from the scene have a higher ISS than patients transported by ground (17.5 vs 13.6; p < 0.001). CONCLUSIONS: Pediatric patients transported by HEMS were as severely injured as those transported by ground, in contrast to adult patients. We conjecture that since trauma triage schemes classically focus on adults, ground personnel are more selective about which patients are flown to a TC, and less selective for pediatric patients. Trauma centers and HEMS programs should develop pediatric trauma triage protocols that do not overemphasize physiologic parameters. 相似文献
48.
49.
Economic costs of functional dyspepsia 总被引:5,自引:0,他引:5
Dyspepsia is defined as chronic or recurrent symptoms believed to originate in the upper gastrointestinal tract. When routine investigation results in no identifiable explanation for those symptoms patients are labelled as having functional dyspepsia. In community-based surveys, approximately 30% of the otherwise apparently healthy population report dyspeptic symptoms and the majority are believed to have functional dyspepsia. Although only 1 in 4 or 5 patients make use of healthcare resources, this patient category is one of the largest in ambulatory care (1.6 to 5% of all consultations in general practice). The annual frequency of consultations for functional dyspepsia in Sweden has been estimated at 47 per 1000 population. In consequence of its high prevalence and associated absenteeism, the total costs of functional dyspepsia are considerable. In Sweden in 1981, the costs were estimated at $US55 000 per 1000 population ($US113 630 in 1991 dollars). The most cost-effective management strategy remains to be defined. Evidence is accumulating that the traditional 'wait-and-see' policy with initial empirical therapeutic trials without investigation may not be the most cost conserving strategy. 相似文献
50.