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991.
Zeigler DW Wang CC Yoast RA Dickinson BD McCaffree MA Robinowitz CB Sterling ML;Council on Scientific Affairs American Medical Association 《Preventive medicine》2005,40(1):23-32
BACKGROUND: Adolescents and college students are at high risk for initiating alcohol use and high-risk (or binge) drinking. There is a growing body of literature on neurotoxic and harmful cognitive effects of drinking by young people. On average, youths take their first drink at age 12 years. METHODS: MEDLINE search on neurologic and cognitive effects of underage drinking. RESULTS: Problematic alcohol consumption is not a benign condition that resolves with age. Individuals who first use alcohol before age 14 years are at increased risk of developing alcohol use disorders. Underage drinkers are susceptible to immediate consequences of alcohol use, including blackouts, hangovers, and alcohol poisoning and are at elevated risk of neurodegeneration (particularly in regions of the brain responsible for learning and memory), impairments in functional brain activity, and the appearance of neurocognitive deficits. Heavy episodic or binge drinking impairs study habits and erodes the development of transitional skills to adulthood. CONCLUSIONS: Underage alcohol use is associated with brain damage and neurocognitive deficits, with implications for learning and intellectual development. Impaired intellectual development may continue to affect individuals into adulthood. It is imperative for policymakers and organized medicine to address the problem of underage drinking. 相似文献
992.
Paul S Mihaljevic T Leacche M Landzberg M Ho CY Blake GJ Byrne JG 《The Annals of thoracic surgery》2005,79(2):701-703
Ventricular septal defect with intramyocardial dissection of the ventricular free wall is a rare complication of myocardial infarction associated with poor prognosis. We describe a patient who developed a ventricular septal defect with intramyocardial dissection of the right ventricular free wall. Initially the patient was successfully stabilized by the placement of a percutaneous closure device. The placement of the device allowed initial hemodynamic recovery of the patient and subsequent definitive surgical repair. This case illustrates the importance of collaboration between interventional cardiologists and cardiac surgeons in the treatment of complex postinfarction ventricular septal defects. 相似文献
993.
Stewart RM Johnston J Geoghegan K Anthony T Myers JG Dent DL Corneille MG Danielson DS Root HD Pruitt BA Cohn SM 《Annals of surgery》2005,241(6):969-977
OBJECTIVE: We set out to compare the malpractice lawsuit risk and incidence in trauma surgery, emergency surgery, and elective surgery at a single academic medical center. SUMMARY AND BACKGROUND DATA: The perceived increased malpractice risk attributed to trauma patients discourages participation in trauma call panels and may influence career choice of surgeons. When questioned, surgeons cite malpractice risk as a rationale for not providing trauma care. Little data substantiate or refute the perceived high trauma malpractice risk. We hypothesized that the malpractice risk was equivalent between an elective surgical practice and a trauma/emergency practice. METHODS: Three prospectively maintained institutional databases were used to calculate and characterize malpractice incidence and risk: a surgical operation database, a trauma registry, and a risk management/malpractice database. Risk groups were divided into elective general surgery (ELECTIVE), urgent/emergent, nontrauma general surgery (URGENT), and trauma surgery (TRAUMA). Malpractice claims incidence was calculated by dividing the total number of filed lawsuits by the total number of operative procedures over a 12-year period. RESULTS: Over the study period, 62,350 operations were performed. A total of 21 lawsuits were served. Seven were dismissed. Three were granted summary judgments to the defendants. Ten were settled with payments to the plaintiffs. One went to trial and resulted in a jury verdict in favor of the defendants. Total paid liability was 4.7 million dollars(391,667 dollars/year). Total legal defense costs were 1.3 million dollars(108,333 dollars/year). The ratio of lawsuits filed/operations performed and incidence in the 3 groups is as follows: ELECTIVE 14/39,080 (3.0 lawsuits/100,000 procedures/year), URGENT 5/17,958, (2.3 lawsuits/100,000 procedures/year), and TRAUMA 2/5312 (3.1/100,000 procedures/year). During the study period, there were an estimated 49,435 trauma patients evaluated. The incidence of malpractice lawsuits using this denominator is 0.34 lawsuits/100,000 patients/year. CONCLUSIONS: These data demonstrate no increased risk of lawsuit when caring for trauma patients, and the actual risk of a malpractice lawsuit was low. 相似文献
994.
Waitzkin H Jasso-Aguilar R Landwehr A Mountain C 《Social science & medicine (1982)》2005,61(5):893-906
Focusing mainly on the United States and Latin America, we aimed to identify the constructions of social reality held by the major stakeholders participating in policy debates about global trade, public health, and health services. In a multi-method, qualitative design, we used three sources of data: research and archival literature, 1980-2004; interviews with key informants who represented major organizations participating in these debates, 2002-2004; and organizational reports, 1980-2004. We targeted several types of organizations: government agencies, international financial institutions (IFIs) and trade organizations, international health organizations, multinational corporations, and advocacy groups. Many governments in Latin America define health as a right and health services as a public good. Thus, the government bears responsibility for that right. In contrast, the US government's philosophy of free trade and promoting a market economy assumes that by expanding the private sector, improved economic conditions will improve overall health with a minimum government provision of health care. US government agencies also view promotion of global health as a means to serve US interests. IFIs have emphasized reforms that include reduction and privatization of public sector services. International health organizations have tended to adopt the policy perspectives of IFIs and trade organizations. Advocacy groups have emphasized the deleterious effects of international trade agreements on public health and health services. Organizational stakeholders hold widely divergent constructions of reality regarding trade, public health, and health services. Social constructions concerning trade and health reflect broad ideologies concerning the impacts of market processes. Such constructions manifest features of "creed," regarding the role of the market in advancing human purposes and meeting human needs. Differences in constructions of trade and health constrain policies to address the profound changes generated by global trade. 相似文献
995.
Quantitative autoradiographic methods for in vivo measurement of regional rates of cerebral blood flow, glucose metabolism, and protein synthesis contribute significantly to our understanding of phsysiological and biochemical responses of the brain to changes in the environment. A disadvantage of these autoradiographic methods is that experimental animals can be studied only once. With the advent of small animal positron emission tomography (PET) and with increases in the sensitivity and spatial resolution of scanners it is now possible to use adaptations of these methods in experimental animals with PET. These developments allow repeated studies of the same animal, including studies of the same animal under different conditions, and longitudinal studies. In this review we summarize the tradeoffs between the use of autoradiography and small animal PET for functional brain imaging studies in animal research. 相似文献
996.
Sofka CM Saboeiro G Adler RS 《Journal of vascular and interventional radiology : JVIR》2005,16(8):1121-1123
PURPOSE: The authors believe that ultrasound as a primary method of image guidance for performing hip aspirations is underutilized, and the authors report their experience in performing ultrasound-guided hip injections in 358 patients, using a free-hand technique. MATERIALS AND METHODS: A retrospective review of all adult ultrasound-guided hip injections performed at the authors' institution over a four-year period was performed. RESULTS: Retrospective review of an ultrasound database revealed 358 adult hip aspirations/injections were performed at the authors' institution from October 2000-October 2004. All procedures were performed using a longitudinal, anterior approach and without the use of a needle guide. There were no reported cases of inadvertent vascular or femoral nerve puncture. CONCLUSIONS: To the authors' knowledge, this is the largest reported series of sonographically-guided adult hip aspirations/injections without the use of a needle guide. The authors believe that ultrasound as a primary method of image guidance for performing hip aspirations is underutilized. The absence of radiation and relatively short procedure time of ultrasound-guided hip injections are favorable factors to both the authors' referring clinician population as well as the patients. 相似文献
997.
Bryan JN Jia F Mohsin H Sivaguru G Miller WH Anderson CJ Henry CJ Lewis MR 《Nuclear medicine and biology》2005,32(8):851-858
Copper-64-labeled monoclonal antibodies (mAbs) have previously demonstrated unexpectedly effective tumor control in rodent models of cancer at relatively low tumor-absorbed radiation doses. This property has been associated with delivery platforms resulting in cellular internalization. The purpose of the present studies was to evaluate the in vitro internalization and in vivo distribution of a two-antibody model of 64Cu radioimmunotherapy (RIT) in the same cell and animal models of cancer. Biodistributions of an internalizing antibody, cBR96, and a noninternalizing antibody, cT84.66, labeled with 64Cu, were obtained in nude mice bearing LS174T colon carcinoma xenografts from 15 min to 48 h. The 64Cu-DOTA-cBR96 conjugate demonstrated rapid tumor uptake, reaching 20.2% ID/g at 3 h and peaking at 35.4% ID/g by 24 h. Tumor accumulation of 64Cu-DOTA-cT84.66 was more gradual, 8.19% ID/g at 3 h and 43.8% ID/g by 24 h, but maximum uptake was not statistically different from 64Cu-DOTA-cBR96. Mouse xenograft dosimetry was estimated to be 1128 rad/mCi (304.9 mGy/MBq) for 64Cu-DOTA-cBR96 and 1409 rad/mCi (380.5 mGy/MBq) for 64Cu-DOTA-cT84.66. In LS174T cells, internalized radioactivity increased by a factor of 3.8 over 4 h for 64Cu-DOTA-cBR96, but remained unchanged 64Cu-DOTA-cT84.66. When normalized to uptake at 1 h, cellular efflux of 64Cu was essentially identical for both mAbs. The biodistributions and tumor dosimetry of these internalizing and noninternalizing radiolabeled mAbs were sufficiently similar for direct comparison of the therapeutic efficacies of low doses of 64Cu RIT agents in the same animal model of cancer. 相似文献
998.
Stretch JR Somorjai R Bourne R Hsiao E Scolyer RA Dolenko B Thompson JF Mountford CE Lean CL 《Annals of surgical oncology》2005,12(11):943-949
Background Nonsurgical assessment of sentinel nodes (SNs) would offer advantages over surgical SN excision by reducing morbidity and
costs. Proton magnetic resonance spectroscopy (MRS) of fine-needle aspirate biopsy (FNAB) specimens identifies melanoma lymph
node metastases. This study was undertaken to determine the accuracy of the MRS method and thereby establish a basis for the
future development of a nonsurgical technique for assessing SNs.
Methods FNAB samples were obtained from 118 biopsy specimens from 77 patients during SN biopsy and regional lymphadenectomy. The specimens
were histologically evaluated and correlated with MRS data. Histopathologic analysis established that 56 specimens contained
metastatic melanoma and that 62 specimens were benign. A linear discriminant analysis–based classifier was developed for benign
tissues and metastases.
Results The presence of metastatic melanoma in lymph nodes was predicted with a sensitivity of 92.9%, a specificity of 90.3%, and
an accuracy of 91.5% in a primary data set. In a second data set that used FNAB samples separate from the original tissue
samples, melanoma metastases were predicted with a sensitivity of 87.5%, a specificity of 90.3%, and an accuracy of 89.1%,
thus supporting the reproducibility of the method.
Conclusions Proton MRS of FNAB samples may provide a robust and accurate diagnosis of metastatic disease in the regional lymph nodes of
melanoma patients. These data indicate the potential for SN staging of melanoma without surgical biopsy and histopathological
evaluation. 相似文献
999.
BACKGROUND: Multi-drug-resistant bacteria are rarely isolated from patients with acute appendicitis. METHODS: Case report and literature review. RESULTS: We report an unusual case of post-appendectomy intra-abdominal abscess with intra- operative cultures that grew multi-drug-resistant Acinetobacter baumannii. An 11-year-old boy underwent open appendectomy for perforated appendicitis. He developed a superficial surgical site infection at the Penrose drain site on the seventh postoperative day; cultures grew multi-drug-resistant Acinetobacter baumannii. A computed tomography scan revealed an intra- abdominal abscess. Open drainage was performed, and intra-operative cultures grew the same multi-drug-resistant A. baumannii along with Escherichia coli. CONCLUSIONS: Post-operative therapy with ceftriaxone may have predisposed the patient to nosocomial infection caused by multi-drug-resistant A. baumannii. 相似文献
1000.
Sengupta S Myers RP Slezak JM Bergstralh EJ Zincke H Blute ML 《The Journal of urology》2005,174(6):2191-2196
PURPOSE: Prostate specific antigen (PSA) is a useful marker for predicting outcomes following treatment for prostate cancer but, given the evolving nature of prostate cancer, there is an ongoing need to refine its use. We assessed preoperative PSA doubling time (PSADT) and PSA velocity (PSAV) as predictors of outcome following radical retropubic prostatectomy (RRP). MATERIALS AND METHODS: We identified 2,290 men who were treated with RRP for prostate cancer between 1990 and 1999 with multiple preoperative PSA measurements available. PSADT was calculated by log linear regression and PSAV was calculated by linear regression. These parameters were used in preoperative and postoperative multivariate models for the end points of biochemical and clinical progression, and cancer death. RESULTS: At a median followup of 7.1 years (range 0.1 to 14.5) biochemical progression, clinical progression and death from prostate cancer were observed in 583, 156 and 42 patients, respectively. The HR for death from prostate cancer was 6.22 (95% CI 3.33 to 11.61) in men with PSADT less than 18 months vs 18 or greater and 6.54 (95% CI 3.51 to 12.19) in men with PSAV greater than 3.4 ng/ml yearly vs 3.4 or less. On multivariate analysis adjusting for preoperative or postoperative variables PSADT and PSAV remained significant predictors of each outcome. When assessed jointly, PSAV was significant as a predictor of biochemical progression, while PSADT was a significant predictor of clinical progression and cancer death. CONCLUSIONS: This study confirms the usefulness of preoperative PSA kinetics for predicting post-RRP outcomes, which may be useful for stratifying patients, so that rational management decisions can be made with respect to observation, intervention and adjuvant treatment. While PSADT maybe biologically more accurate and stronger on multivariate analysis, PSAV is clinically easier to use and a good approximation in the short term. 相似文献