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排序方式: 共有162条查询结果,搜索用时 15 毫秒
1.
Use of the Neodymium: yttrium -aluminum -garnet (Nd:YAG) laser to recanalize stenosed arteries may require delivery of the beam through blood. To assess the degree of hemolysis and debris formation, 54 samples of citrated whole blood were exposed to Nd:YAG laser radiation of varying powers (10, 20 and 30 watts) and duration (1, 2.5 and 5 seconds). Compared to control samples which were not subjected to laser light, there was no significant decrease in hematocrit (41 to 40.5 +/- 5%), hemoglobin concentration (13.8 to 13.8 +/- .06 g/1OO ml), or increase in "free" hemoglobin concentration. Debris weight (from .45 +/- .002 to .45 +/- .002 mg), as well as the white blood cell count, was also not significantly changed (from 5,400 to 5,200 +/- 240 WBC/cm). Light microscopy examination of debris from samples of whole blood, washed erythrocytes, and platelet-rich plasma subjected to the laser at 30 watts for five seconds failed to demonstrate the presence of membrane denaturation of blood elements, as compared with the morphologic changes observed in whole blood samples exposed to a "hot tip" rather than Nd:YAG laser radiation. Nd:YAG laser can be used intravascularly without fear of hemolysis or debris "micro-embolization" up to a power of 30 watts for five seconds.  相似文献   
2.
Massive pulmonary embolism: triple-armed therapy   总被引:2,自引:0,他引:2  
Many patients who suffer a massive pulmonary embolus die despite emergent therapy. In these desperately ill patients an aggressive, combined method of management was initiated to improve their chances and quality of survival. During a 5-year period 10 patients were treated with (1) low-dose topical, intrapulmonary thrombolytic therapy to dissolve thrombus, (streptokinase or urokinase); (2) anticoagulation to prevent thrombus propagation (heparin); and (3) the simultaneous insertion of a Greenfield filter to prevent the early, recurrent, and therefore potentially fatal pulmonary embolus--"triple-armed therapy." Thrombolytic therapy was administered through a Swan-Ganz catheter wedged against the pulmonary embolus. During the same interval 10 other patients also sustained massive pulmonary emboli but were treated only with systemic heparin. Serial pulmonary arteriography was performed daily. The patients treated by triple-armed therapy responded favorably with a rapid (less than 6 hours), significant improvement in PaO2, pulmonary artery pressure, cardiac output, pulmonary vascular resistance, and blood pressure, compared with patients treated with continuous heparin alone. Nine patients in the triple-armed therapy group survived whereas only six in the heparin group survived. Two additional patients were treated by triple-armed therapy and had thrombolysis with triple-armed therapy with tissue plasminogen activator; these patients demonstrated the most rapid improvement in cardiorespiratory dynamics and arteriographic clearance of emboli. This management protocol shows promise for patients who sustain a massive pulmonary embolus, because it reduces the morbidity associated with pulmonary embolectomy while avoiding the hazards associated with systemic thrombolytic therapy.  相似文献   
3.
ObjectiveTo review the pathophysiology of Fontan-associated liver disease, its histologic changes, and its radiologic manifestations.ConclusionsFontan-associated liver disease is the result of a set of structural and functional changes in the liver that occur secondary to hemodynamic changes brought about by Fontan surgery. The radiologic manifestations of Fontan-associated liver disease consist of changes in the size and shape of the liver, alterations in the signal intensity or pattern of enhancement, abnormalities in the vascular structures, and focal lesions, which include benign nodules with intense uptake in the arterial phase and hepatocellular carcinoma. Radiologists need to be familiar with this disease and its complications, because the number of patients who undergo Fontan surgery continues to increase, and these patients undergo an increasing number of imaging tests.  相似文献   
4.
Mycobacterium smegmati s (Ms) is a nonpathogenic mycobacteria of rapid growth, which shares many characteristics with Mycobacterium tuberculosis (MTB), the major causative agent of tuberculosis. MTB has several cell wall glycolipids in common with Ms, which play an important role in the pathogenesis of tuberculosis and the induction of a protective immune response against MTB infection in some animal models. In this study, the humoral immune response and cross reactivity against MTB, of liposomes containing a mixture of cell wall glycolipids of Ms and commercial lipids was evaluated, in order to study its possible use as a component of a vaccine candidate against tuberculosis. Liposomes containing total lipids extracted from Ms, distearoyl phosphatidyl choline and cholesterol were prepared by the dehydration-rehydration technique. Balb/c mice were immunized with the liposomes obtained and the antibody response and cross reactivity against MTB were tested by ELISA. Total lipids extract from Ms showed the presence of several polar glycolipids in common with MTB, such as phosphatidylinositol mannosides. Liposomes that contained glycolipids of Ms were capable of inducing a specific IgG antibody response that allowed the recognition of surface antigens of MTB. The results of this study demonstrated the presence of immunogenic glycolipids in Ms, which could be included to enhance the protective effects of subunit vaccine formulations against tuberculosis.  相似文献   
5.
The development of a new tuberculosis (TB) vaccine has become one of the main objectives of the scientific community. Protein antigens have been widely explored as subunit TB vaccines, however lipid antigens could be equally important to be used or included in such a vaccine. The aim of this study was to demonstrate the potential of a liposome formulation composed of an extract of lipids from Mycobacterium smegmatis (Ms) as a TB vaccine candidate. We evaluated the immunogenicity of this formulation as well as the cross reactive response against antigens from Mycobacterium tuberculosis (MTb) in BALB/c mice. We determined the anti-liposome IgG response in sera from TB patients and from healthy subjects who displayed a positive (PPD+) or negative (PPD-) tuberculin skin test. A significant increase in anti-liposome IgG (p<0.05) was detected in animals immunized with Bacille Calmette-Guérin (BCG) compared with all groups, and in the group immunized with liposomes from Ms (LMs) compared to animals immunized with either LMs adjuvanted with aluminium (LMs-A) or the negative control group (phosphate buffered saline, PBS) respectively. With respect to the cross reactive response against a cocktail of cell wall antigens (CWA) from MTb, significantly higher IgG levels were observed in animals immunized with BCG and LMs compared to negative controls and either, aluminium-adjuvanted liposomes (LMs-A) or montanide (LMs-M) (p<0.05). Furthermore, the anti-liposome IgG response was significantly superior in sera from pulmonary TB patients compared to PPD+ and PPD- healthy subjects (p<0.001) suggesting the expression of these antigens in vivo during active MTb infection. The results obtained provide some evidence for the potential use of liposomes containing total lipid extracts of Ms as a TB vaccine candidate.  相似文献   
6.
Patient centeredness is an increasingly recognized aspect of quality health care. The application of this framework to contraceptive counseling and care has not been well described. We propose a definition of patient-centered contraceptive counseling that focuses on and prioritizes each patient’s individual needs and preferences regarding contraceptive methods and the counseling experience. Guided by this definition, we review recent research that has advanced our understanding of how patient-centered contraceptive counseling can be delivered in practice, focusing on how women decide on a contraceptive method, their preferences for counseling, and their experiences with counseling. This research provides evidence that women have diverse preferences around attributes of their contraceptive methods and value personal, supportive relationships with their family planning providers that focus on their individual preferences. We discuss the implications of this research for practice and review recent interventions that incorporate patient centeredness to varying degrees.  相似文献   
7.

Background

Unintended pregnancy (UIP) is a persistent public health concern in the United States disproportionately experienced by racial/ethnic minorities and women of low socioeconomic status. UIP often occurs with experiences of reproductive coercion (RC) and intimate partner violence (IPV). The purpose of the study was to qualitatively describe and compare contexts for UIP risk between low-income Black and White women with histories of IPV/RC.

Study Design

Semistructured interviews were conducted with low-income Black and White women with histories of IPV or RC, ages 18 to 29 years, recruited from family planning clinics in Pittsburgh, Pennsylvania.

Results

Interviews with 10 non-Hispanic Black women and 34 non-Hispanic White women (N = 44) were included in the analysis. Differences between White and Black women emerged regarding IPV/RC experiences, gender roles in intimate relationships, and trauma histories, including childhood adversity. Fatal threats and IPV related to childbearing were most influential among White women. Among Black women, pregnancy was greatly influenced by RC related to impending incarceration, subfertility, and condom nonuse, and decisions about contraception were often dependent on the male. Sexual abuse, including childhood sexual assault, in the context of sexual/reproductive health was more prominent among White women. Childhood experiences of neglect impacted pregnancy intention and love-seeking behaviors among Black women.

Conclusions

Racial differences exist in experiences of IPV/RC with regard to UIP even among women with similar economic resources and health care access. These findings provide much-needed context to the persistent racial/ethnic disparities in UIP and illustrate influences beyond differential access to care and socioeconomic status.  相似文献   
8.

Background

Although pregnancy intention is strongly associated with contraceptive use, little is known about the interaction between pregnancy intention and attitude, or how they jointly affect contraceptive use.

Methods

Cross-sectional data from a national survey of women veterans who receive care within the Veterans Affairs Healthcare System were used to examine relationships among pregnancy intention (in next year, in >1 year, never, not sure), attitude toward hypothetical pregnancy (worst thing, neutral, best thing), and contraceptive use among women at risk for unintended pregnancy. Bivariate and multivariable analyses assessed associations between pregnancy intention and attitude, both separately and jointly, with contraceptive use. Multinomial regression assessed the relationship of intention and attitude with contraceptive method effectiveness.

Results

Among 858 women at risk of unintended pregnancy, bivariate analysis demonstrated that pregnancy intention and attitude were associated, but not perfectly aligned. In logistic regression models including both variables, intention of never versus in next year (adjusted odds ratio [aOR], 2.78; 95% confidence interval [CI], 1.34–5.75) and attitude of worst thing versus best thing (aOR, 2.86; 95% CI, 1.42–5.74) were each positively associated with contraception use. Among women using contraception, intention of never (aOR, 3.17; 95% CI, 1.33–7.59) and attitude of worst thing (OR, 2.09; 95% CI, 1.05–4.17) were associated with use of highly effective (e.g., intrauterine devices and implants) versus least effective (e.g., barrier) methods.

Conclusions

These findings support prior research suggesting that pregnancy intention alone does not fully explain contraceptive behaviors and imply that attitude toward pregnancy plays an important role in shaping contraceptive use independent of pregnancy intentions.  相似文献   
9.
10.
OBJECTIVE: To examine the independent effects of race or ethnicity and insurance status on use of tubal sterilization rates. METHODS: This study used cross-sectional data collected by the 2002 National Survey of Family Growth. The survey is designed to represent women and men aged 15-44 years in the household population of the United States. Our main outcome measure was tubal sterilization at any time before interview. A multivariable logistic regression model was used to estimate the effects of race or ethnicity and insurance status on rates of tubal sterilization after adjusting for important confounders. RESULTS: The sample consisted of 7,643 women: 66% were white, 15% were Hispanic, and 14% were African American; 68% had private insurance and 32% had public or no insurance. After adjusting for age, insurance status, parity, income, education, marital status, and religion, African-American women were more likely than white women to undergo tubal sterilization (adjusted odds ratio 1.43, 95% confidence interval 1.08-1.88). After adjusting for age, race or ethnicity, parity, income, education, marital status, and religion, women with public or no insurance were more likely to undergo sterilization compared with women with private insurance (adjusted odds ratio 1.38, 95% confidence interval 1.09-1.74). CONCLUSION: African-American women and women with no or public insurance were more likely to have undergone tubal sterilization compared with white women and women with private insurance, respectively. Additional research to identify factors that influence women's decision to undergo sterilization is warranted. LEVEL OF EVIDENCE: II.  相似文献   
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