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201.
Ruth A. Etzel David L. Ashley 《International archives of occupational and environmental health》1994,66(2):125-129
Between March and November of 1991, approximately 9000 workers from 43 different countries battled the burning oil wells in Kuwait. To document the exposure of persons in Kuwait during the oil well fires to volatile organic compounds (VOCs), we obtained samples of blood from 14 U.S. personnel in Kuwait City in May of 1991 (group I) and 40 American firefighters working in the oil fields in October of 1991 (group II). Concentrations of VOCs in group I and group II were compared with those of a random sample of 114 persons in the United States (reference group). The median concentrations of VOCs in group I were equal to or lower than those in the reference group. We found significant differences between the median concentrations of several VOCs in group 11 and the reference group. Median levels of ethylbenzene were about 10 times higher among group II than among the reference group (0.53 g/I vs 0.052 g/l). Median levels of benzene, m-/p-xylene, o-xylene, styrene, and toluene among group II were more than double those of the reference group. Although firefighters had higher median concentrations of VOCs than the reference group, those American personnel in Kuwait not involved in fighting the oil fires had concentrations of VOCs comparable to those in the reference group. Blood VOC measurements indicate a significant increase in exposure to VOCs in firefighters, but do not demonstrate this in personnel in Kuwait City. 相似文献
202.
Ruth Chadwick 《Health, risk & society》1999,1(3):293-300
This paper addresses two competing perspectives choice and responsibility for the individual undergoing genetic resting and counselling, and the tension between them. A comparison with models applied to vaccination demonstrates the changes in ethical frameworks considered appropriate over time. The move from choice to responsibility, it is argued, is due to a number of reasons, including the value impact of new technology, which affect how concepts are interpreted. From a contrast between choice and coercion, with autonomy interpreted as self-determination, there has been a shift, through autonomy versus paternalism, to tensions between choice and responsibility, which depend on rival notions of autonomy. Thus, while the public health model of vaccination has been problematised, and the individual choice model in genetics has been questioned, the challenge to choice in the genetic context however tends not to be framed explicitly in public health terms so much as in the form of individual responsibility and solidarity. 相似文献
203.
Tailoring Antireflux Surgery: A Randomized Clinical Trial 总被引:6,自引:0,他引:6
A hypothesis has been formulated that mandates the adjustment of antireflux surgery to either a total or a partial wrap depending
on the motor function of the esophagus to avoid dysphagia and other obstructive complaints. This hypothesis has been tested
in a randomized, clinical trial where 106 chronic gastroesophageal reflux patients were allocated to either a total Nissen-Rossetti
(n= 53) or a Toupet partial posterior (n= 53) fundoplication, irrespective of their preoperative esophageal motor function. All patients were followed at least 3
years, during which time none had a relapse of moderate to severe reflux symptoms. Motor dysfunctions defined as peristaltic
amplitude ≤ 30 mmHg in the distal third and failed primary peristalsis with or without > 20% simultaneous contractions were
noted in 67 patients preoperatively, but these patients did not have a specific symptom profile (e.g., dominated by obstructive
symptoms) nor did seven patients with “aperistaltic esophagus.” The incidence of dysphagia decreased from 20% preoperatively
to 8% (mild) at 3 years after the operation with no difference between the surgical procedures. We were unable to demonstrate
a relation between preoperative manometric findings and postoperative symptoms when assessed in the total group or when subdivided
by the type of fundoplication (r < 0.3). Flatulence occurred more frequently among those with a total fundic wrap (p < 0.01). When patients representing motor dysfunction (see above) were specifically analyzed, we again observed no difference
in outcome between those having a total or a partial fundic wrap. In conclusion, the concept of tailoring antireflux surgery
based on the preoperative motor function of the esophagus in patients with chronic gastroesophageal reflux disease was not
supported by the results of this clinical trial. 相似文献
204.
The Ultrapulse CO2 laser (Coherent Inc., Palo Alto, CA, USA) was used in 239 patients, from March 1996 to July 1998, for full-face laser resurfacing.
In 106 (43%) of these patients rhytidectomy was performed in the same procedure. All patients submitted to laser resurfacing
were prepared for 1 to 2 months beforehand with retinoic acid and hydroquinone. The procedures were done under local anesthesia
controlled by an anesthesiologist. A clear film dressing impregnated with silicone gel (Silon TSR; Bio-Med Sciences, Bethlehem,
PA, USA) was used for 6 to 7 days and complete healing was observed in 7 to 10 days. Complications were exclusively dermatologic,
without relation to surgery. No necrosis of the cutaneous flap was observed. Skin biopsies of 10 consecutive patients undergoing
the combined procedures revealed no vascular impairment to the dermis. The patients were able to resume their activities 2
weeks after the procedure. 相似文献
205.
Ba 《Health & social care in the community》1999,7(3):216-224
There are increasing numbers of children with a disability living in the community who require enteral tube feeds to optimize their nutritional status. Whilst there appears to be evidence of health gains, for some children there may also be serious and unintended social deprivations resulting from the need to be tube fed. This paper reviews the literature on support for children who are tube fed and makes a case for more coordinated and effective support services for families who are tube feeding a child at home. It is argued that national guidance should be developed which clarifies the position of all non-parent carers and staff who are willing to administer enteral tube feeds. Such guidance should also ensure that enterally-fed children have the same rights to educational and social services as other children and that families are given the opportunity to make informed decisions about the implications of enteral feeding prior to it being established. 相似文献
206.
Howard Hochster Ruth Oratz David S. Ettinger Ernest Borden 《Investigational new drugs》1999,16(3):259-263
Purpose: Didemnin B is a novel marine natural product cyclic depsipeptide containing unusual amino acid moieties. This agent demonstrates promising preclinical antitumor activity, including activity against B16 melanoma and against melanoma isolates in the human tumor stem cell assay.Methods: We conducted a phase II study of Didemnin B, given in Cremophor, at a starting dose of 4.2 mg/m2/IV q 28 days. Patients with measurable metastatic or advanced malignant melanoma were eligible. All patients were previously untreated with chemotherapy and had performance status 0 or 1. Doses were escalated to 4.9 and 5.6 mg/m2 in cycles 2 and 3, respectively.Results: Nineteen patients were entered and treated with a median of one cycle per patient. Eight of these patients went off study for toxicity including 7 with anaphylactoid reactions in the first or second cycle. One patient went off study after 3 cycles with severe myopathy, a newly described toxicity. Two were not evaluable for response and five were considered stable, including one patient with a transient PR of soft tissue disease in the first cycle. Another patient had stable disease for twelve cycles before progressing and one went off study electively after 3 cycles, for a total of 7 patients with stable disease. One patient with a measurable partial remission (PR) and went off study after three cycles due to severe myopathy, a then newly-described toxicity. No hematologic toxicity was seen. Nausea and vomiting were controlled with anti-emetics.Conclusions: This study was indeterminate with respect to the activity of Didemnin B in melanoma. Signs of activity were seen, particularly in soft tissue masses, though a large number of patients could not be evaluated fully for activity due to the occurrence of anaphylactoid reactions. This study does not preclude a clinically important level of activity for Didemnin B. 相似文献
207.
Stephen Brady Ph.D. C. Michael Hiam Ph.D. Ruth Saemann Psy.D. Laurie Humbert Ph.D. Michael Z. Fleming Ed.D. K. Dawkins-Brickhouse Ph.D. 《Community mental health journal》1996,32(6):573-578
The treatment of dual diagnosis, co-occurring substance abuse and mental illness, calls for addressing two serious and often confounding problems. The authors introduce an expanded version of the transtheoretical model of change as formulated by J.O. Prochaska and C.C. DiClemente, and suggest that this new version offers a pragmatic approach to the conceptualization and treatment of dual diagnosis. The potential utility of the treatment model is presented through the authors' experiences in working with inner-city, chronic mentally ill individuals with substance abuse problems. Practical guidelines for dual diagnosis group therapy are discussed.Dr. Brady is an assistant research professor at the Boston University School of Medicine and the deputy superintendent for research and training at the Dr. Solomon Carter Fuller Mental Health Center. Drs. Hiam, Saemann, Humbert, Fleming and Brickhouse were senior members of the clinical/administrative staff at the Fuller MHC. 相似文献
208.
Dr. Douglas B. Evans MD Marsha L. Frazier PhD Chusilp Charnsangavej MD Ruth L. Katz MD Lilly Larry BS James L. Abbruzzese MD 《Annals of surgical oncology》1996,3(3):241-246
Background: The K-ras oncogene is activated by point mutations at codon 12 in most patients with exocrine pancreatic cancer. Mutant-enriched
polymerase chain reaction (PCR) amplification can enhance the detection of mutated K-ras. This technique was applied to patients
undergoing percutaneous fine-needle aspiration (FNA) biopsy of suspect pancreatic lesions.
Methods: Twenty-five patients underwent percutaneous FNA of the pancreas for cytologic and molecular analysis. After preparing cytologic
smears, the 22-gauge needle and syringe used for FNA were rinsed in RPMI-1640. The specimen was centrifuged, and DNA was extracted
from the supernatant and subjected to mutant-enriched PCR using appropriate mismatched primers that introduce a BstNI restriction
endonuclease cleavage site at codon 12 of wild-type, but not mutant, K-ras. After digestion with BstNI, the DNA was reamplified. To increase assay sensitivity, the final five PCR cycles were completed
incorporating 5 μCi of (α-32P)dCTP. The DNA was then redigested and subjected to gel electrophoresis and autoradiography.
Results: The median amount of DNA retrieved per specimen was 3.33 μg. Mutant K-ras was detected as a band of 143 bps; residual wild-type DNA was seen as a 114-bp fragment. Twenty-one of 25 specimens demonstrated
mutated K-ras DNA. Two patients with nondiagnostic cytology results had mutated K-ras DNA; adenocarcinoma of pancreatic origin was confirmed in both cases after pancreatectomy.
Conclusion: The molecular diagnosis of pancreatic cancer through identification of mutations in K-ras can be readily performed on specimens obtained by percutaneous FNA. As aggressive multimodality management of this disease
becomes more common, pretreatment analysis of molecular determinants may have greater clinical significance.
Presented at the 48th Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995. 相似文献
209.
E. Louise R. Phillips MN Ruth E. Little ScD Robert S. Hillman MD Robert F. Labbe PhD Caryl Campbell BS 《Alcoholism, clinical and experimental research》1984,8(2):233-237
The sweat patch is a new, noninvasive method designed to estimate the ethanol consumption of drinking subjects. It consists of salt-impregnated absorbent pads protected by a plastic chamber with attached water-tight adhesive. The patch reportedly collects transepidermal fluid at a steady rate for up to 10 days. Recent laboratory research has indicated a linear relationship between the concentration of ethanol in transepidermal fluid and mean concentration of ethanol in blood. Levels of ethanol in the sweat patch allowed identification of persons drinking at least 0.5 g of ethanol/kg/day with 100% sensitivity and specificity. The study reported here was conducted to test the field effectiveness of this sweat patch in normal, active research subjects. First, several pretests were conducted to determine the optimal location of the patch on the body and its fluid uptake at various sites. A laboratory experiment using nonalcoholic subjects was conducted to replicate previous work, and methods of measuring ethanol concentration in the patch were refined. A field test of the patch was then carried out. Healthy active volunteers drank a single "moderate" dose of ethanol (0.5 g of ETOH/kg of body weight) and then remained abstinent for the next 3 days. A week later, a "heavy" dose (1.0/kg of body weight) was consumed. Only a trace of ethanol was detected in any of the patches worn in either experiment. The patch did not measure ethanol in the transepidermal fluid under field conditions. Thus, further design modifications and pilot testing are required before the full benefits of this unobtrusive measure of drinking can be realized. 相似文献
210.