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排序方式: 共有864条查询结果,搜索用时 31 毫秒
81.
Tehei M Franzetti B Wood K Gabel F Fabiani E Jasnin M Zamponi M Oesterhelt D Zaccai G Ginzburg M Ginzburg BZ 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(3):766-771
Intracellular water dynamics in Haloarcula marismortui, an extremely halophilic organism originally isolated from the Dead Sea, was studied by neutron scattering. The water in centrifuged cell pellets was examined by means of two spectrometers, IN6 and IN16, sensitive to motions with time scales of 10 ps and 1 ns, respectively. From IN6 data, a translational diffusion constant of 1.3 x 10(-5) cm(2) s(-1) was determined at 285 K. This value is close to that found previously for other cells and close to that for bulk water, as well as that of the water in the 3.5 M NaCl solution bathing the cells. A very slow water component was discovered from the IN16 data. At 285 K the water-protons of this component displays a residence time of 411 ps (compared with a few ps in bulk water). At 300 K, the residence time dropped to 243 ps and was associated with a translational diffusion of 9.3 x 10(-8) cm(2) s(-1), or 250 times lower than that of bulk water. This slow water accounts for approximately 76% of cell water in H. marismortui. No such water was found in Escherichia coli measured on BSS, a neutron spectrometer with properties similar to those of IN16. It is hypothesized that the slow mobility of a large part of H. marismortui cell water indicates a specific water structure responsible for the large amounts of K(+) bound within these extremophile cells. 相似文献
82.
Heuer GG Gabel BC Bhowmick DA Stiefel MF Hurst RW Schuster JM 《Journal of neurosurgery. Spine》2008,8(4):381-384
Spinal arteriovenous fistulas (AVFs) are relatively uncommon lesions that are often diagnosed in a delayed fashion. The authors present a cause of a symptomatic high-flow AVF that developed in a patient after traumatic injury to the upper cervical spine. The patient presented to the trauma bay after a motor vehicle collision, and was found to have a C-2 fracture involving the transverse foramen. Although the patient was neurologically intact on presentation, 6 hours after admission weakness developed on his left side. Imaging studies demonstrated complete transection of the distal cervical aspect of the right vertebral artery (VA) at the base of C-2, with antegrade and retrograde flow into a direct AVF, resulting in early filling of the right internal jugular vein and other external draining veins. The patient was treated endovascularly with coil occlusion of the VA both proximal and distal to the transection. The patient's weakness improved over the next 7 days. At the 12-week follow-up examination, the patient's fractures had healed and he was neurologically intact. 相似文献
83.
Kourosh Jafarnia Gerard T. Gabel Bernard F. Morrey 《Operative Techniques in Sports Medicine》2001,9(4):217-221
Elbow extension is very critical for the throwing athlete. The extensor mechanism of the elbow is a relativelyuncommon source of clinical dysfunction. However, two primary processes may affect the triceps tendon, triceps tendonitis, and triceps avulsion injuries. Triceps tendonitis, the more common of the two, is manifested by chronic posterior elbow pain with extension activities. It occurs almost exclusively in males, usually in the fourth decade of life, and especially in individuals who perform forceful repetitive extension activities, eg, throwing athletes. Two distinct subsets of patients exist: those with and those without an olecranon traction spur. Conservative management involves avoidance of repetitive forceful elbow extension, nonsteroidal anti-inflammatories, and time. Splinting in 45° of elbow flexion may be useful if tolerated. Counterforce bracing is typically unsuccessful because the cross-section of the arm changes with biceps contraction. Corticosteroid injection is contraindicated. Although conservative management is limited in scope, it is usually successful in triceps tendonitis in the absence of an olecranon traction spur. The presence of an olecranon traction spur is associated with a higher failure rate of conservative treatment necessitating surgical intervention. Surgical management, when required, involves subperiosteal exposure and excision of the spur and the olecranon tip and formal repair of the triceps tendon. 相似文献
84.
K. Gabel PhD RD R. Newman PhD RD G. Lauritzen PhD RD G. Auld PhD RD M. Bock PhD RD C. Bruhn PhD Y. Lee PhD D. Medeiros PhD RD J. McNulty DrPH RD S. Nitzke PhD RD M. Ortiz PhD E. Sheehan PhD Rd 《Nutrition Research》1997,17(11-12)
Numerous dietary recommendations aim to decrease fat and increase fiber in the American diet, yet obesity remains a major public health problem in the United States as indicated by excessive weight for height ratios. The purpose of the Western Regional Project 182 was to examine knowledge, attitudes, and practices of the general population in 11 states and the District of Columbia regarding dietary fat and fiber. This paper specifically discusses the survey results related to the relationships of fat and fiber knowledge and food behavior to body mass index (BMI). Using self-reported weight and height, it was estimated that more than one third of the respondents (n = 1297, 42%) had a BMI ≥ 26. Subjects with BMI scores less than 26 generally had the highest knowledge scores of all BMI groups, but no significant differences in fat knowledge were found among the BMI classifications. Behavior that was related to fat intake was significantly (p < 0.05) different in respondents with a BMI < 26 as compared to those with higher BMI scores. Gender differences for fat, fiber, and overall behavior were also highly significant (p < 0.0001) with favorable diet-related behaviors exhibited by females. Education, income level, residence, and age were consistently related to the BMI of females, but not males. Women who graduated from college, earned more than $50,000 per year, and lived in an urban location of >250,000 people were most likely to have a lower BMI than females with other educational levels, lower economic categories, and from less populated areas. Results support continued use of government and private funds to educate Americans to improve diet and achieve acceptable weights for heights. 相似文献
85.
86.
87.
Abstract The objective of this study was to evaluate the utility of a polymerase chain reaction (PCR) assay in detecting Mycobacterium tuberculosis in bronchoalveolar lavage (BAL) specimens of patients suspected of having active pulmonary tuberculosis (TB) but who were sputum smear-negative. Patients undergoing investigation for suspected pulmonary TB at the University Hospital, Kuala Lumpur, and who were sputum smear-negative underwent fibreoptic bronchoscopy and BAL. One portion of each lavage specimen was submitted for smear examination for acid-fast bacilli and mycobacterial culture and the other portion assayed by PCR for the presence of a 562-base pair DNA segment belonging to the insertion sequence IS986, unique to the M. tuberculosis complex. As controls, lavage specimens from patients with other lung lesions were also similarly tested. The PCR assay gave a positivity rate of 80.9% (55 of 68) compared with 8.8% of smear examination and 7.4% of culture for detecting M. tuberculosis in BAL specimens. The assay was positive in two of 45 BAL specimens from 35 control subjects. The PCR assay was more sensitive than smear and culture in detecting M. tuberculosis in BAL specimens of patients with sputum smear-negative pulmonary TB. 相似文献
88.
Bernard MY Cheung THY Au SY Chan CM Lam SH Lau RP Lee SF Lee WS Lo EHF Sin MY Tang HH Tsang 《Experimental & Clinical Cardiology》2005,10(1):21-24
BACKGROUND:
Psychosocial stress can be the cause or the consequence of hypertension.OBJECTIVE:
To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.SUBJECTS AND METHODS:
Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.RESULTS:
The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.CONCLUSIONS:
Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong. 相似文献89.
Norman I. Levenson Robert J. Adolph Donald W. Romhilt Marjorie Gabel Vincent J. Sodd Leon S. August 《The American journal of cardiology》1975,35(2):251-257
The effect of regional myocardial ischemia and hypoxia on myocardial scintigraphy was studied in patients and dogs after intravenous administration of cesium-129. Seven men with angiographically proved ischemic heart disease underwent exercise testing and 129Cs was given immediately when ischemia was manifested in the electrocardiogram. Defects were not evident in the scintigrams of any patient. Failure to visualize a defect might be related to delayed uptake of 129Cs by the myocardium (maximal uptake in 45 minutes). The ischemic state was dissipated before the disparity in uptake between normal and ischemic myocardium could be visualized. Cesium-129 is useful for identifying acute myocardial infarcts but should not be used to visualize transient exercise-induced regional ischemia.Six dogs were given 129Cs after induction of regional myocardial hypoxia by perfusion of the anterior descending coronary artery with venous blood. In each, scintigraphy revealed a defect that resolved after reperfusion with arterial blood. Two other dogs were given 129Cs before perfusion with hypoxemic blood; neither dog manifested a defect. Since perfusion was maintained by a pump these results suggest that the major cause of the scintigraphically observed defect was inadequate cellular uptake of 129Cs rather than excessive cellular loss. Since regional myocardial hypoxia produced a reversible defect, scintigraphic studies might overestimate the size of an acute myocardial infarct in man by including the ischemic zone surrounding the infarct. 相似文献
90.
Pneumatosis cystoides intestinalis is a rarely observed disorder on plain abdominal X-ray or colonoscopy examination. Although causing few complaints in adults, it can nevertheless lead to gastrointestinal bleeding. In the reported case, gastrointestinal bleeding was observed with coinciding pneumatosis and phenprocoumon therapy. After stopping anticoagulant therapy, pneumatosis vanished completely, thus suggesting that phenprocoumon is probably a further cause of the cystic disease. In the known list of drugs able to provoke pneumatosis, this case adds a new mechanism of affliction different to either immunosuppression or gas production. 相似文献