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61.
An increasing number of Lesbians are choosing to have children. Do nurses interact with the couples differently during the childbirth experience?  相似文献   
62.
Transient evoked otoacoustic emissions (TEOAEs) are low amplitude sound waves produced by the healthy cochlea. They can be recorded with a microphone in the external ear. TEOAEs are abolished by hearing losses of 30 dB or more. The feasibility of using TEOAEs as a screening test for hearing loss in children was studied. TEOAE recordings were attempted in 56 children attending an audiology clinic. Recordings were possible from both ears in 52 children; of these 104 ears, 32 had hearing deficits of 30 dB or more. Hearing status was compared with the results of six TEOAE screening criteria. All criteria had a sensitivity of 1.00. Four standard TEOAE criteria yielded specificities of 0.46-0.58. Two new criteria derived from analysis of limited frequencies from the TEOAE waveform gave specificities of 0.76 and 0.82. It can be concluded that, when appropriate pass/fail criteria are employed, TEOAEs are a feasible screening test in children.  相似文献   
63.
In our department 24 patients underwent treatment of invasive trophoblastic tumours from 1975 to 1984. In 13 cases we were dealing with invasive bladder moles and in 11 cases with chorionic carcinoma. Nine women became pregnant, among them one case of chorionic carcinoma. Eight women were delivered of a viable child on average 30 months after the end of the treatment, whereas one patient wanted termination of pregnancy. Six women had undergone a methotrexate monotherapy before, two women a sequential treatment with methotrexate + actinomycine D. The undisturbed pregnancies and births of eight healthy babies point to an unimpaired fertility after chemotherapy of trophoblastic tumours.  相似文献   
64.
BACKGROUND: Single-photon emission computed tomography (SPECT) sestamibi (MIBI) is an excellent tool for detection of coronary artery disease (CAD), preoperative risk assessment, and follow-up management after coronary revascularization. While the sensitivity of MIBI SPECT for detecting CAD has been reported to exceed 90%, the specificity ranges between 53-100%. HYPOTHESIS: The study was undertaken to assess characteristics of patients with abnormal stress technetium Tc99m sestamibi SPECT (MIBI) studies without significant coronary artery diameter stenoses (< 50%). METHODS: Between January 1999 and November 2000, 270 consecutive patients were referred for coronary angiography due to reversible MIBI uptake defects during exercise. In 41 patients (15%; 39% women, mean age 59 +/- 9 years), reversible MIBI uptake defects were assessed although coronary angiography showed no significant CAD. These patients were compared with age- and gender-matched patients with perfusion abnormalities (39% women, mean age 60 +/- 9 years), due to significant CAD (coronary artery stenosis > 50%). RESULTS: There were no significant differences between the two groups regarding body mass index, left bundle-branch block (LBBB), or method of stress test (dipyridamole in patients with LBBB or physical inactivity [n = 11] and exercise in all the others [n = 30]). Left ventricular hypertrophy (44 vs. 23%, p = 0.05) and left anterior fascicular block (LAFB) (17 vs. 0%, p = 0.005) were more common in patients with perfusion abnormalities with no significant CAD, whereas ST-segment depression during exercise (17 vs. 37% p = 0.05) and angina during exercise (15 vs. 29%, p = 0.02) were significantly less common than in patients with abnormal MIBI perfusion studies and angiographically significant CAD. Sestamibi uptake defects during exercise were significantly smaller in patients without significant CAD than in matched controls with significant CAD (p < 0.0004). CONCLUSION: Of 270 consecutive patients, 41 (15%) referred to coronary angiography due to reversible MIBI uptake defects showed coronary artery stenoses < 50%. Twenty-six (10%) of these presented angiographically normal coronary arteries. The significantly higher proportion of left ventricular hypertrophy and LAFB in patients with reversible MIBI uptake defects without significant CAD suggest microvascular disease, angiographically underestimated CAD, and conduction abnormalities as underlying mechanisms.  相似文献   
65.
The aging process at the cellular, organ and whole organism levels is in many respects a mystery. A common bias among those who study aging is that cellular homeostasis "generally falls apart". The assumption of a general deterioration in cellular homeostasis does not take into account that many individuals age quite well maintaining even robust physiological and mental functions. One facet of aging studies that has come to the forefront is the impact of age on the control of the ion messenger, calcium. Emerging evidence suggests that despite age-related declines in any one component or multiple components of the calcium buffering systems, compensatory mechanisms may be able to maintain overall calcium homeostasis. This brief review focuses specifically on the ability of peripheral neurons to maintain control of the ion messenger calcium with advancing age. In addition, the idea that the impact of age on calcium homeostasis may be more subtle due to complex and integrated mechanisms that control this ion is discussed.  相似文献   
66.
BACKGROUND: To distinguish true local recurrences (TR) from new primary tumors (NP) and to assess whether this distinction has prognostic value in patients who develop ipsilateral breast tumor recurrences (IBTR) after breast-conserving surgery and radiotherapy. METHODS: Between 1970 and 1994, 1339 patients underwent breast-conserving surgery at The University of Texas M. D. Anderson Cancer Center for ductal carcinoma in situ or invasive carcinoma. Of these patients, 139 (10.4%) had an IBTR as the first site of failure. For the 126 patients with clinical data available for retrospective review, we classified the IBTR as a TR if it was located within 3 cm of the primary tumor bed and was of the same histologic subtype. All other IBTRs were designated NP. RESULTS: Of the 126 patients, 48 (38%) patients were classified as NP and 78 (62%) as TR. Mean time to disease recurrence was 7.3 years for NP versus 5.6 years for TR (P = 0.0669). The patients with NP had improved 10-year rates of overall survival (NP 77% vs. TR 46%, P = 0.0002), cause-specific survival (NP 83% vs. TR 49%, P = 0.0001), and distant disease-free survival (NP 77% vs. TR 26%, P < 0.0001). Patients with NP more often developed contralateral breast carcinoma (10-year rate: NP 29% vs. TR 8%, P = 0.0043), but were less likely to develop a second local recurrence after salvage treatment of the first IBTR (NP 2% vs. TR 18%, P = 0.008). CONCLUSIONS: Patients with NP had significantly better survival rates than those with TR, but were more likely to develop contralateral breast carcinoma. Distinguishing new breast carcinomas from local disease recurrences may have importance in therapeutic decisions and chemoprevention strategies. This is because patients with new carcinomas had significantly lower rates of metastasis than those with local disease recurrence, but were more likely to develop contralateral breast carcinomas.  相似文献   
67.
Background Our aim was to identify predictors of locoregional recurrence (LRR) in patients with early-stage breast cancer treated with breast-conserving therapy (BCT) and long-term follow-up. Methods From 1970 to 1994, 1153 patients with stage I to II breast cancer underwent BCT and radiotherapy at our institution. Patients with prior breast cancer or other primary malignancies were excluded. Clinical and pathologic characteristics evaluated were age, race, tumor size, stage, pathologic tumor margins, axillary nodal involvement, estrogen and progesterone receptor status, Black's nuclear grade, type of surgery, and use of adjuvant therapy. Results Of 1083 patients, 54% presented with stage I disease and 46% with stage II disease. Median age was 50 years, and median follow-up was 9 years. Axillary nodes were positive in 31% of the patients who underwent axillary dissection. LRR developed in 6%, LRR followed by systemic recurrence in 5%, and systemic recurrence alone in 13%, 76% had no evidence of recurrence at last follow-up. Age, tumor size, positive lymph nodes, and not receiving chemotherapy or hormonal therapy were independent predictors of LRR. Disease-specific survival among patients with LRR was similar to that among patients with no recurrence. Conclusions Multidisciplinary treatment strategies should be used to accomplish durable locoregional control after BCT. Presented at the 54th Annual Cancer Symposium of the Society of Surgical Oncology, Washington, DC, March 15–18, 2001.  相似文献   
68.
69.
Background Breast-conservation surgery plus radiotherapy has become the standard of care for early-stage breast cancer; we evaluated its long-term complications. Methods We selected patients treated with surgery and radiotherapy between January 1990 and December 1992 (an era in which standard radiation dosages were used) with follow-up for at least 1 year. Patients were prospectively monitored for treatment-related complications. Median follow-up time was 89 months. Results A total of 294 patients met the selection criteria. Grade 2 or higher late complications were identified in 29 patients and included arm edema in 13 patients, breast skin fibrosis in 12, decreased range of motion in 4, pneumonitis in 2, neuropathy in 2, fat necrosis in 1, and rib fracture in 1. Arm edema was more common after lumpectomy plus axillary node dissection than after lumpectomy alone. Arm edema occurred in 18% of patients who underwent surgery plus irradiation of the lymph nodes and 10% who underwent surgery without nodal irradiation. Conclusions Breast-conservation surgery plus radiotherapy was associated with grade 2 or higher complications in only 9.9% of patients. Half of these complications were attributable to axillary dissection, it is hoped that lower complication rates can be achieved with sentinel lymph node biopsy.  相似文献   
70.
Background: Although preoperative chemotherapy has become the standard of care for inoperable locally advanced breast cancer, its role for downstaging resectable primary tumors is still evolving. The purpose of this study was to determine whether the prognostic information from an axillary node dissection in patients with clinical T3N0 breast cancer was altered by preoperative chemotherapy compared with surgery de novo.Methods: Between 1976 and 1994, 91 patients with clinically node-negative operable T3 breast cancer received doxorubicin-based combination chemotherapy on protocol at one institution. Fifty-three patients received both preoperative and postoperative chemotherapy (PreopCT), and 38 received postoperative chemotherapy only (PostopCT). All patients underwent axillary lymph node dissection as part of their definitive surgical treatment. There were no differences between the PreopCT and PostopCT groups in median age (51 vs. 49 years), median tumor size at presentation (6 cm vs. 6 cm), tumor grade, or estrogen receptor status (estrogen receptor negative 38% vs. 32%). The median follow-up time was 7 years.Results: Patients in the PreopCT group had fewer histologically positive lymph nodes (median, 0 vs. 3, P < .01), and a lower incidence of extranodal extension (19% vs. 42%, P 5 .02). By univariate analysis, the number of pathologically positive lymph nodes (P < .01) and extranodal extension (P < .01) were predictors of disease-specific survival in PreopCT patients. Multivariate analysis showed that extranodal extension was the only independent prognostic factor in PreopCT patients (P < .01). Overall, PreopCT and PostopCT patients had similar 5-year disease-free survival rates (66% vs. 57%); however, PreopCT patients had worse disease-free (P 5 .01) and diseasespecific survival (P 5 .04) when survival was compared after adjustment for the number of positive lymph nodes. Furthermore, PreopCT patients with 4–9 positive lymph nodes had a lower 5-year disease-free survival rate than PostopCT patients with 4–9 positive nodes (17 vs. 48%, P 5 .04).Conclusions: Axillary lymph node status remains prognostic after chemotherapy. Pathologically positive lymph nodes after preoperative chemotherapy are associated with a worse prognosis than the same nodal status before chemotherapy.  相似文献   
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