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1.
A patent foramen ovale (PFO) is an embryological remnant found in 27% of adults. It is a potential right-to-left intracardiac shunt. Shunting may be the result of reversal in the interatrial pressure gradient or abnormal streaming of blood in the right atrium. The pathologic consequences of right-to-left shunting include hypoxemia and paradoxical embolism. PFO may exacerbate preexisting hypoxemia or be its primary cause. Paradoxical embolism through a PFO is well documented. Its role in cryptogenic stroke remains controversial. A PFO may be detected by both invasive and noninvasive techniques. Contrast transesophageal echocardiography with provocative maneuvers is the diagnostic method of choice allowing visualization of the shunt. Patients with cryptogenic stroke should be screened for a PFO. If detected, noninvasive studies for deep vein thrombosis are recommended. Treatment must be tailored to the presentation. Surgical or transcatheter closure is recommended for hypoxemia. Prevention of venous embolism (air or thrombus) with or without closure of the PFO is recommended for paradoxical embolism.  相似文献   
2.
Adjuvant chemotherapy for breast carcinoma: psychosocial implications.   总被引:6,自引:0,他引:6  
B E Meyerowitz  F C Sparks  I K Spears 《Cancer》1979,43(5):1613-1618
Fifty women receiving adjuvant chemotherapy after surgery for Stage II breast carcinoma were interviewed in an effort to describe the psychosocial effect of the treatment. Perceptions of emotional distress and behavioral disruption were rated in five areas, yielding a rating of overall level of disruption and distress. Results showed that all women experienced adverse changes while receiving adjuvant treatments. Of the 50 women, 88% described a decrease in activities related to the effects of adjuvant chemotherapy; 54% reported an increased financial burden; and 41% claimed that their family and/or sexual life had been adversely affected. Despite these adverse changes, 74% of these patients "would definitely" recommend the treatment to friends in a similar situation. Results from this preliminary study may provide useful information to potential participants in adjuvant trials and to the physicians who conduct such trials.  相似文献   
3.

Background

Cracked teeth are ubiquitous in the adult dentition. The objective of this study was to determine which patient traits and behaviors and external tooth and crack characteristics correlate with cracked teeth being symptomatic.

Methods

Dentists in The National Dental Practice-Based Research Network enrolled a convenience sample of patients each with a single, vital posterior tooth with at least 1 observable external crack in this observational study; they enrolled 2,975 cracked teeth from 209 practitioners. The authors collected data at the patient level, tooth level, and crack level. They used generalized estimating equations to obtain significant (P < .05) independent odds ratios (OR) associated with teeth that were symptomatic for a crack.

Results

Characteristics positively associated with cracked tooth symptoms, after adjusting for demographics, included patients who clenched, ground, or pressed their teeth together (OR, 1.30; 95% confidence interval [CI], 1.12-1.50), molars (OR, 1.58; 95% CI, 1.30-1.92), teeth with a wear facet through enamel (OR, 1.22; 95% CI, 1.01-1.40), carious lesions (OR, 1.31; 95% CI, 1.07-1.60), cracks that were on the distal surface of the tooth (OR, 1.31; 95% CI, 1.13-1.52), and cracks that blocked transilluminated light (OR, 1.31, 95% CI, 1.09-1.57). Teeth with stained cracks were negatively associated with having cracked tooth symptoms (OR, 0.68; 95% CI, 0.55-0.84).

Conclusions

The greatest likelihood of a cracked tooth being symptomatic was found when patients reported clenching or grinding their teeth and had a molar with a distal crack that blocked transilluminated light.

Practical Implications

This information can help inform dentists in the decision-making process regarding the prognosis for a cracked tooth.  相似文献   
4.
We have constructed a restriction fragment length polymorphism linkage map for the nuclear genome of the flowering plant Arabidopsis thaliana. The map, containing 90 randomly distributed molecular markers, is physically very dense; greater than 50% of the genome is within 1.9 centimorgans, or approximately 270 kilobase pairs, of the mapped DNA fragments. The map was based on the meiotic segregation of markers in two different crosses. The restriction fragment length polymorphism linkage groups were integrated with the five classically mapped linkage groups by virtue of mapped mutations included in these crosses. Markers consist of both cloned Arabidopsis genes and random low-copy-number genomic DNA clones that are able to detect polymorphisms with the restriction enzymes EcoRI, Bgl II, and/or Xba I. These cloned markers can serve as starting points for chromosome walking, allowing for the isolation of Arabidopsis genes of known map location. The restriction fragment length polymorphism map also can associate clones of unknown gene function with mutant phenotypes, and vice versa.  相似文献   
5.
The plant hormone ethylene regulates a variety of processes of growth and development. To identify components in the ethylene signal transduction pathway, we screened for ethylene-insensitive mutants in Arabidopsis thaliana and isolated a dominant etr2-1 mutant. The etr2-1 mutation confers ethylene insensitivity in several processes, including etiolated seedling elongation, leaf expansion, and leaf senescence. Double mutant analysis indicates that ETR2 acts upstream of CTR1, which codes for a Raf-related protein kinase. We cloned the ETR2 gene on the basis of its map position, and we found that it exhibits sequence homology to the ethylene receptor gene ETR1 and the ETR1-like ERS gene. ETR2 may thus encode a third ethylene receptor in Arabidopsis, transducing the hormonal signal through its “two-component” structure. Expression studies show that ETR2 is ubiquitously expressed and has a higher expression in some tissues, including inflorescence and floral meristems, petals, and ovules.  相似文献   
6.
7.
BACKGROUND: Tissue-sparing approaches to primary treatment and reconstructive options provide improved cosmetic outcomes for women with breast cancer. Earlier research has suggested that conservation or restitution of the breast might mitigate the negative effects of breast cancer on women's sexual well-being. Few studies, however, have compared psychosocial outcomes of women who underwent lumpectomy, mastectomy alone, or mastectomy with reconstruction. To address some of these issues, we examined women's adaptation to surgery in two large cohorts of breast cancer survivors. METHODS: A total of 1957 breast cancer survivors (1-5 years after diagnosis) from two major metropolitan areas were assessed in two waves with the use of a self-report questionnaire that included a number of standardized measures of health-related quality of life, body image, and physical and sexual functioning. All P: values are two-sided. RESULTS: More than one half (57%) of the women underwent lumpectomy, 26% had mastectomy alone, and 17% had mastectomy with reconstruction. As in earlier studies, women in the mastectomy with reconstruction group were younger than those in the lumpectomy or mastectomy-alone groups (mean ages = 50.3, 55.9, and 58.9, respectively; P: =.0001); they were also more likely to have a partner and to be college educated, affluent, and white. Women in both mastectomy groups complained of more physical symptoms related to their surgeries than women in the lumpectomy group. However, the groups did not differ in emotional, social, or role function. Of interest, women in the mastectomy with reconstruction group were most likely to report that breast cancer had had a negative impact on their sex lives (45.4% versus 29.8% for lumpectomy and 41.3% for mastectomy alone; P: =. 0001). CONCLUSIONS: The psychosocial impact of type of primary surgery for breast cancer occurs largely in areas of body image and feelings of attractiveness, with women receiving lumpectomy experiencing the most positive outcome. Beyond the first year after diagnosis, a woman's quality of life is more likely influenced by her age or exposure to adjuvant therapy than by her breast surgery.  相似文献   
8.
Psychosocial implications of adjuvant chemotherapy. A two-year follow-up   总被引:1,自引:0,他引:1  
Transsphenoidal hypophysectomy was performed in 13 patients with advanced malignant melanoma. Although three minor responses were observed, there were no complete or partial responses. All three patients with bone pain had a decrease in discomfort lasting 1-2 months. All five patients with minor responses or stable disease had postoperative decreases in the excretion of the dihydroxyphenylalanine (DOPA) metabolite 3-O-methyldopamine; all but one patient with clinical progression had postoperative increases in excretion. Average survival of those whose postoperative excretion fell (143 +/- days; range, 60-217+) was significantly longer (P less than 0.004) than that of those whose postsurgical values rose (30 days; range, 15-58).  相似文献   
9.
B R Meyerowitz 《Surgery》1966,60(3):521-535
  相似文献   
10.
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