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排序方式: 共有653条查询结果,搜索用时 15 毫秒
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J D Helman J M Leung W H Bellows N Pineda G W Roach J D Reeves J Howse M T McEnany D T Mangano 《Anesthesiology》1992,77(1):47-62
Desflurane, a coronary vasodilator, may induce myocardial ischemia in patients with coronary artery disease. To determine whether desflurane is safe to administer to the at-risk patient population (with known coronary artery disease), we compared the incidence and characteristics of perioperative myocardial ischemia in 200 patients undergoing coronary artery bypass graft (CABG) surgery randomly assigned to receive desflurane (thiopental adjuvant) versus sufentanil anesthesia. Under conditions of hemodynamic control, perioperative ischemia was assessed using continuous echocardiography (precordial: during induction; transesophageal: during surgery) and Holter electrocardiography (ECG); hemodynamics (including pulmonary artery pressure) were measured continuously. Hemodynamic results: During induction, no significant changes in hemodynamics occurred in the sufentanil group, while in the desflurane group, heart rate, systemic and pulmonary arterial pressure increased and stroke volume decreased significantly. During the intraoperative period, the incidence of hemodynamic variations was low in both anesthetic groups; however, the prebypass incidence of tachycardia (greater than 120% of preoperative baseline heart rate) was greater in the desflurane group (4 +/- 7% of total time monitored) than in the sufentanil group (1 +/- 6%) (P = 0.0003). Similarly, the incidence of prebypass hypotension (less than 80% of preoperative baseline systolic arterial blood pressure) was greater in the desflurane group (21 +/- 14%) than in the sufentanil group (15 +/- 16%) (P = 0.01). ECG results: Preoperatively, 15% (28/191) of patients developed ECG ischemia, with no difference between patients who received desflurane, 13% (12/96) or sufentanil, 16% (16/95) (P = 0.6). During anesthetic induction, 9% (9/99) of patients who received desflurane developed ECG ischemia, compared with 0% (0/98) who received sufentanil (P = 0.007). During the prebypass period, 5% (10/197) of patients developed ECG ischemia, with no difference between patients who received desflurane, 7% (7/99) or sufentanil, 3% (3/98) (P = 0.3). Postbypass, 12% (24/194) of patients developed ECG ischemic changes, with no difference between patients who received desflurane, 13% (13/97) or sufentanil, 11% (11/96) (P = 0.9). Echocardiographic results: The incidence of precordial echocardiographic ischemia during anesthetic induction was 13% (5/39) in the desflurane group versus 0% (0/29) in the sufentanil group (P = 0.1). Moderate to severe transesophageal echocardiographic (TEE) ischemic episodes occurred in 12% (21/175) of patients during prebypass, with no significant difference between the desflurane group, 16% (15/91) and the sufentanil group, 7% (6/84) (P = 0.09). TEE ischemic episodes occurred in 27% (49/178) of patients during the postbypass period, with no difference between the desflurane, 29% (27/92) and sufentanil, 25% (22/86) groups (P = 0.7).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
3.
Savanah Elliott Morgan L. McCloskey Susan L. Johnson Noereem Z. Mena Taren Swindle Laura L. Bellows 《Journal of nutrition education and behavior》2021,53(2):164-173
ObjectiveExplore using food photography to assess packed lunches in a university-based Early Childhood Center and contextualize these photographs through parent interviews.MethodsAn explanatory sequential design was used. Packed lunches were photographed to assess the type and quantity of foods offered and consumed by Child and Adult Food Care Program components (fruit, vegetable, grain, and protein) and quality of foods offered using the Healthy Meal Index. Parent interviews aimed to understand motivations and behaviors related to packing lunch.ResultsData were collected on 401 lunches. Only 16.2% of lunches met all Child and Adult Food Care Program requirements. Most lunches included fruit (84%) and grains (82%), whereas fewer included vegetables (44%). Portion sizes were large, especially for grains (2.7 ± 1.5 servings). In interviews (n = 24), parents expressed tension between offering healthful items and foods they knew their child would eat, as well as concern about children going hungry.Conclusions and ImplicationsFood photography is a feasible methodology to capture parent-packed lunches for preschoolers and may have utility in nutrition education, particularly related to age-appropriate portion sizes. 相似文献
4.
Ann K. Blanc Katharine J. McCarthy Charlotte Warren Ashish Bajracharya Benjamin Bellows 《Studies in family planning》2021,52(1):77-93
Population‐based indicators of the coverage of key elements of high‐quality family planning services are tracked via household surveys with female respondents, yet little work has been done to establish their validity. We take advantage of existing data sets from Cambodia and Kenya to compare women's responses at exit interviews following a health facility visit against the observations of a trained third‐party observer during the visit. The results, which treat the observations as the reference standard, show that indicators that measure contraceptive methods received are accurately reported while indicators of whether the woman received her preferred method and whether information was “discussed” or “explained” during counseling are less reliably reported. Studies designed explicitly to assess the validity of family planning questions in household surveys, especially questions in large survey programs critical for monitoring demographic trends and programmatic coverage, are needed. 相似文献
5.
6.
van Kranen HJ; van Iersel PW; Rijnkels JM; Beems DB; Alink GM; van Kreijl CF 《Carcinogenesis》1998,19(9):1597-1601
The variation in colorectal cancer (CRC) incidence worldwide strongly
suggests a role for dietary influences. Based on epidemiological data,
protective effects of vegetables and fruit intake on CRC are widely
claimed, while other data indicate a possible increased CRC risk from
(higher) dietary fat intake. Therefore, we have investigated single and
interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in
the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this
study, four different diets (A-D) were compared, which were either low in
fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In
addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced
by a freeze-dried VFM. The diets were balanced so that they only differed
among each other in fat/carbohydrate content and the presence of specific
plant-constituents. Because the initiation of intestinal tumors in ApcMin
mice occurs relatively early in life, exposure to the diets was started in
utero. Without the addition of VFM, mice maintained at a high-fat diet did
not develop significantly higher numbers of small or large intestinal
adenomas than mice maintained at a low-fat diet. VFM added to a low-fat
diet significantly lowered multiplicity of small intestinal polyps (from
16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male
ApcMin mice only. Strikingly, addition of VFM to female mice maintained on
a low-fat diet and to both sexes maintained on a high-fat diet
significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7
polyps/mouse). In conclusion, our results indicate that neither a lower fat
intake nor consumption of VFM included in a high-fat diet decreases the
development of polyps in mice genetically predisposed to intestinal tumor
development.
相似文献
7.
Long-term efficacy of argon laser trabeculoplasty 总被引:3,自引:0,他引:3
B J Shingleton C U Richter A R Bellows B T Hutchinson R J Glynn 《Ophthalmology》1987,94(12):1513-1518
Long-term efficacy of 360 degrees argon laser trabeculoplasty was studied in 118 eyes of 93 patients with uncontrolled chronic open-angle glaucoma. The mean intraocular pressure (IOP) decrease was 8.9 +/- 5.4 mmHg (mean +/- standard deviation [SD] in 71 eyes at 1 year, 9.3 +/- 4.3 mmHg (mean +/- SD) in 51 eyes at 3 years, and 10.3 +/- 3.9 mmHg (mean +/- SD) in 28 eyes at 5 years. The probability of success at 4 years (decrease in IOP greater than or equal to 3 mmHg, IOP less than or equal to 19 mmHg, stable visual field, stable optic nerve, and no further laser or surgical intervention) was 52%. Pretreatment IOP, diagnosis, previous operations, age, and sex were not significant determinants for success or failure. Eyes receiving argon laser trabeculoplasty before cataract surgery maintained control of IOP after surgery. Failure was most common in the first year after treatment (23%), and thereafter failure occurred at a rate of 7 to 10% per year. 相似文献
8.
Controversy exists in the literature concerning the potentiating effect of heparin on the inactivation rate of factor XIa by antithrombin III (AT III) in both purified systems and in plasma. We have analyzed the factors that could influence this reaction and found that ionic strength of the medium, as well as the type and concentration of the heparin preparations accounted for the major discrepancies in the literature. At I = 0.43 N, a preparation of bovine lung heparin at 1 U/mL did not augment the inactivation rate of factor XIa by inhibitors in plasma or by purified AT III. However, when ionic strength was decreased, a progressive increase in the potentiating effect was observed, reaching 6.5-fold at I = 0.15 N. At saturating concentrations of heparin, which results in the formation of 100% AT III-heparin complex, (greater than ten-fold molar excess over AT III) in purified systems, all heparin preparations (porcine, bovine, low molecular weight [LMW], and high affinity) yielded an approximately 30-fold augmentation of the factor XIa inactivation rate. However, when heparin was less than saturating, we observed that various heparin preparations affected the AT III-induced inactivation of factor XIa to different degrees even though they exhibited the same inhibitory activity (1 U/mL) against thrombin. This variation resulted from differences in the number of AT III binding sites in each heparin preparation, despite a similar Kd for each. Addition of high molecular weight kininogen (HK) to AT III-heparin complexes did not enhance their ability to inhibit factor XIa, and high concentrations of HK decreased the inactivation rate. A high therapeutic dose of heparin only permits the formation of 2.5% to 16.5% of the AT III-heparin complexes that can be achieved at saturation. We observed that 1 U/mL heparin (bovine lung heparin) (high therapeutic concentration) in virtually undiluted plasma only accelerated the inactivation rate of factor XIa (in the absence of other active enzymes) less than two-fold. These new observations further support our previous conclusion that therapeutic levels of heparin have little to no influence on the inactivation rate of factor XIa in plasma. 相似文献
9.
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis. 相似文献
10.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797