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41.
S Manam R D Storer S Prahalada K R Leander A R Kraynak B J Ledwith M J van Zwieten M O Bradley W W Nichols 《Cancer research》1992,52(12):3347-3352
We compared the profile of ras gene mutations in spontaneous CD-1 mouse liver tumors with that found in liver tumors that were induced by a single i.p. injection of either 7,12-dimethylbenz(a)anthracene (DMBA), 4-aminoazobenzene, N-hydroxy-2-acetylaminofluorene, or N-nitrosodiethylamine. By direct sequencing of polymerase chain reaction-amplified tumor DNA, the carcinogen-induced tumors were found to have much higher frequencies of ras gene activation than spontaneous tumors. Furthermore, each carcinogen caused specific types of ras mutations not detected in spontaneous tumors, including several novel mutations not previously associated with either the carcinogen or mouse hepatocarcinogenesis. For example, the model compound DMBA is known to cause predominantly A to T transversions in Ha-ras codon 61 in mouse skin and mammary tumors, consistent with the ability of DMBA to form bulky adducts with adenosine. Our results demonstrate that the predominant mutation caused by DMBA in mouse liver tumors is a G to C transversion in Ki-ras codon 13 (DMBA is also known to form guanosine adducts), illustrating the influence of both chemical- and tissue-specific factors in determining the type of ras gene mutations in a tumor. 4-Aminoazobenzene and N-hydroxy-2-acetylaminofluorene also caused the Ki-ras codon 13 mutation. In addition, we found that N-nitrosodiethylamine, 4-aminoazobenzene, and N-hydroxy-2-acetylaminofluorene all caused G to T transversions in the N-ras gene (codons 12 or 13). This is the first demonstration of N-ras mutations in mouse liver tumors, establishing a role for the N-ras gene in mouse liver carcinogenesis. Finally, comparison of the ras mutations detected in the direct tumor analysis with those detected after NIH3T3 cell transfection indicates that spontaneous ras mutations (in Ha-ras codon 61) are often present in only a small fraction of the tumor cells, raising the possibility that they may sometimes occur as a late event in CD-1 mouse hepatocarcinogenesis. 相似文献
42.
S F Bradley 《Clinics in Geriatric Medicine》1992,8(4):853-868
Elderly patients with chronic illnesses are at increased risk of becoming colonized or infected with methicillin-resistant Staphylococcus aureus (MRSA). Therapeutic choices for the treatment of MRSA have been limited by the ever-expanding resistance of organisms and drug toxicity. In hospitals, the MRSA carrier state has been associated with increased risk of infection and possible dissemination of the organism to other patients. The epidemiology of MRSA and its significance in long-term care have been less well defined. Isolation procedures and steps to contain or eradicate MRSA should be accommodated to the individual needs of the facility and its resources. 相似文献
43.
R L Becker J F Norfray G P Teitelbaum W G Bradley J B Jacobs L Wacaser R L Rieman 《AJNR. American journal of neuroradiology》1988,9(5):885-889
Four patients with intracranial aneurysm clips made from a variety of alloys were studied without incidence by MR imaging at field strengths ranging from 0.35 to 0.6 T. Knowledge of the type of alloy used in the manufacturing of an aneurysm clip is important in determining whether the clip will or will not deflect in a magnetic field. Ferromagnetic clips show deflection and torque in a magnetic field and have the potential to dislodge from the aneurysm. Nonferromagnetic or weakly ferromagnetic aneurysm clips such as the Sugita (Elgiloy), Yasargil (316 LVM stainless steel), Heifetz (Elgiloy), Yasargil (Phynox), and Vari-Angle McFadden (MP35N) do not deflect or deflect weakly in the magnetic field and therefore would not be expected to dislodge during MR. The option of imaging many patients with intracranial aneurysm clips with MR extends the usefulness of the technique to a previously excluded population. 相似文献
44.
The swab count has traditionally used a swab rack. A new alternative 'bag' method involves placing used swabs in batches of five into plastic bags which are sealed and stored in a bin. A randomized prospective study was carried out to compare these two methods. Twenty consecutive ear, nose and throat cases were randomized to rack or bag collection. Swab-related activities were divided into three categories and analysed by formal time-and-motion criteria. Blood contamination of operating theatre and circulating personnel was recorded. The time involved in all three swab-related activities was significantly less using the bag technique. There was no theatre blood contamination using this method, but significant contamination occurred using the rack. Circulating theatre personnel were minimally contaminated in two cases using the bag method but were grossly contaminated in all ten cases using the rack method. The bag technique is therefore safe and time efficient. 相似文献
45.
S E Kowalski B D Bradley R A Greengrass J Freedman M K Younes 《Anesthesia and analgesia》1992,75(3):400-404
Several authors have questioned the potential for phrenic nerve paralysis with interpleural analgesia. This study was designed to examine the potential for phrenic nerve paralysis with the use of interpleural bupivacaine in dogs. Seven dogs were anesthetized, tracheally intubated, and allowed to breathe spontaneously with halothane/oxygen while in the supine position. After a midline laparotomy, two wires were inserted into the costal portion of each hemidiaphragm for measurement of electromyographic (EMG) signals. A balloon catheter was placed in the abdominal cavity to measure abdominal pressure. The abdomen was then closed. Airway pressure was measured through a side port in the endotracheal tube. Bilateral interpleural catheters were inserted with the loss-of-resistance technique. Each dog was used for two experiments, one on each side, except for one animal. To assess the contribution of the ipsilateral diaphragm to total respiratory effort, the airway was occluded at functional residual capacity for three consecutive breaths, and EMG, airway pressure, and abdominal pressure were measured. In five of nine experiments with bupivacaine, there was complete loss of EMG activity on the side of the injection. In two dogs, there was partial loss of diaphragmatic function, and in the remaining two, there was no change in EMG. In the normal saline solution group (n = 4), there was no change in the EMG. Two dogs that received bilateral bupivacaine injections developed paradoxical respiration with negative inspiratory intraabdominal pressures. Phrenic nerve paralysis or paresis can occur with interpleural blockade. The factors affecting the occurrence of this complication remain to be elucidated. 相似文献
46.
Masahiko Yanagita Bradley J Willcox Kamal H Masaki Randi Chen Qimei He Beatriz L Rodriguez Hirotsugu Ueshima J David Curb 《The American journal of geriatric psychiatry》2006,14(12):1060-1068
OBJECTIVE: The objective of this study was to examine the relation of physical performance measures with depressive symptoms in older men. METHOD: A cross-sectional, multivariate comparison of several measures of upper- and lower-extremity performance and their relation with depressive symptoms was performed in 2,856 older Japanese American men, aged 71-93 years, who participated in the fourth examination of the Honolulu Heart Program. Depressive symptoms were measured using an 11-item version of Center for Epidemiologic Studies Depression (CES-D) Scale. A score of at least 9 (from a maximum score of 33) is considered clinically significant. Timed functional performance tests, including walking and repeated chair stands, were used to assess lower-extremity performance; handgrip strength was used as an indicator of upper-extremity performance. RESULTS: Two hundred eighty-three participants (9.9%) had a score of 9 or greater on the 11-question CES-D Scale and were considered to be at high risk for depression. Time to walk 10 feet and time to complete five chair stands were significantly longer in those with depressive symptoms, whereas handgrip strength was significantly lower. Only the association of gait speed (time to walk 10 feet) and depressive symptoms remained significant when all physical performance measures were simultaneously included in a multivariate analysis. CONCLUSION: These results demonstrate physical performance measures, particularly gait speed, may be important potential correlates of depression in community-dwelling older men. 相似文献
47.
April R. Bradley Elizabeth A. Yeater William O’Donohue 《The journal of primary prevention》2009,30(6):697-715
This study evaluated the short-term effectiveness of a mixed-gender sexual assault prevention program developed for college
students. Program participants (n = 177) were compared to non-program participants (n = 132) prior to the program and during a 2-week follow-up period on measures of rape myths, victim empathy, perceived negative
consequences and estimated likelihood of committing rape, sexual communication, sexual assault awareness, and risky dating
behavior. The prevention program was effective at increasing men’s victim empathy and decreasing their adherence to rape myths
but ineffective at changing women’s assault-related knowledge, participation in risky dating behaviors, and sexual communication
strategies. Limitations of the study and directions for future research in sexual assault prevention are addressed. Editors’ Strategic Implications: This study provides an important example of the limitations of a single session prevention programming approach (even if
it is well designed and executed) in addressing a systemic and pervasive problem like sexual assault on college campuses. 相似文献
48.
Bradley J Katz John R Burroughs Richard L Anderson Shannon Bownds John D McCann 《Movement disorders》2007,22(2):231-234
We present a patient with a facial movement disorder that has characteristics of both blepharospasm and bilateral asynchronous hemifacial spasm. Because of the increased incidence of blepharospasm in patients with hemifacial spasm, our patient's clinical presentation is probably not a chance occurrence, but rather a manifestation of some predisposition for these two movement disorders. This unusual constellation of signs and symptoms challenges the current diagnostic criteria and suggests that some of these facial movement disorders may lie on a spectrum, rather than represent distinct entities. 相似文献
49.
Bryce A Johnson Maneesh R Amancharla Bradley R Merk 《American journal of orthopedics (Belle Mead, N.J.)》2007,36(8):439-441
Dislocation of the proximal tibiofibular joint (PTFJ) in association with a displaced tibial shaft fracture and an intact fibula is an exceedingly rare injury. We present 2 cases of tibia fractures associated with an intact fibula and a PTFJ dislocation. The first case involves a man who sustained a closed spiral fracture of the distal tibial shaft, with an intact fibula, an anterolaterally dislocated PTFJ, and a partial tear of the lateral collateral ligament. The tibia was percutaneously plated, and the PTFJ was reduced and then stabilized with temporary screw fixation. The second case involves a woman who sustained a closed fracture of the tibia in association with a PTFJ dislocation. The tibia was fixed with an intramedullary nail, and the PTFJ was similarly reduced and fixed with a temporary screw. We also provide a brief literature review focusing on classification of PTFJ dislocations, mechanism of injury, associated injuries, and treatment options. 相似文献
50.