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991.
In the companion paper, we showed that the spontaneous firing activity of DRN 5-HT neurons is significantly higher in male (M) than in freely cycling female (CF) rats. Moreover, during pregnancy, it increased in parallel to circulating levels of progesterone, peaking at day 17 of pregnancy (P17). In this second part, we assessed the role of three regulatory mechanisms potentially involved in these modifications of the 5-HT neurons firing activity. During pregnancy, the ED(50) for the response to LSD was decreased by about 70%, indicating a partial desensitization of 5-HT(1A) autoreceptors, which is consistent with the 5-HT neurons higher firing activity. The GABAergic tonic inhibition of 5-HT neurons was assessed using the responses to GABA, bicuculline and isoniazid. Together, they indicate a lower GABAergic tonic inhibition in males and P17 as compared to CF, which is in agreement with their greater 5-HT neurons firing rate. Finally, the efficacy of the long feedback loop, involving postsynaptic 5-HT(1A) receptors, did not seem affected by gender, ovariectomy or pregnancy since the response to systemic 8-OH-DPAT was similar. These results constitute strong evidence of mechanisms by which gender and hormonal fluctuations can modulate the 5-HT neurons function and influence vulnerability to mood disorders. 相似文献
992.
Jon F. Kerner Jeanne S. Mandelblatt Rebecca A. Silliman John J. Lynch Ruby Senie Caryn Cohen Yi-Ting Hwang 《Breast cancer research and treatment》2001,69(1):81-91
Objective.To examine the impact of mammography screening on treatment options received by a cohort of older breast cancer patients.
Setting and population.We studied 718 newly diagnosed breast cancer patients, 67 years and over, diagnosed with TNM Stage I and II disease between 1995 and 1997 at 29 hospitals in five regions.
Methods.Data were collected from patients, surgeons, and medical records. A breast cancer diagnosis was considered to have been by screening mammography if so reported by both patient and medical records. Bivariate and logistic regression were used to identify predictors of a women having her cancer detected by screening mammography and the relationships between mode of detection, stage of disease at diagnosis, and local treatment.
Results.Women with high school or greater education were 1.75 times (95%, CI 1.11–2.75) more likely to have their cancers diagnosed by screening mammography than women who had not completed high school, controlling for other factors. Screening found earlier stage disease: 96% of women with mammographically diagnosed cancer had T1 lesions, compared to 81% of women diagnosed by other means (p=0.001). Women with mammography detected lesions were more likely to have ductal cancer, and to be referred to radiation oncologists more than women diagnosed by other means. Controlling for stage and histology, screening remained associated with a higher likelihood of receiving breast conserving surgery (BCS) with radiation (RT) (OR 1.56, 95%, CI 1.10–2.22) than other local therapies.
Conclusions.Beyond the impact on stage, ductal cancers were more likely to be diagnosed by screening. Mammographically detected lesions were associated with referrals to radiation oncologists and higher rates of BCS and RT. Research is needed to explain the residual independent effects of mammography screening on breast cancer treatment. 相似文献
993.
Madan-Sharma R Kloppenburg M Kornaat PR Botha-Scheepers SA Le Graverand MP Bloem JL Watt I 《Skeletal radiology》2008,37(9):805-811
PURPOSE: The purpose of the study was to relate magnetic resonance imaging (MRI) features at baseline with radiographically determined joint space narrowing (JSN) in the medial compartment of the knee after 2 years in a group of patients with symptomatic osteoarthritis at multiple joint sites. MATERIALS AND METHODS: MRI of the knee and standardized radiographs were obtained at baseline and after 2 years in 186 patients (81% female; aged 43-76 years; mean 60 years). MRI was analyzed for bone marrow lesions, cysts, osteophytes, hyaline cartilage defects, joint effusion, and meniscal pathology in the medial compartment. Radiographs were scored semiquantitatively for JSN in the medial tibiofemoral joint using the Osteoarthritis Research Society International (OARSI) atlas. Radiological progression was defined as >/=1 grade increase. Associations between baseline magnetic resonance (MR) parameters and subsequent radiographic JSN changes were assessed using logistic regression. Relative risk (RR) was then calculated. RESULTS: Radiographic progression of JSN was observed in 17 (9.1%) of 186 patients. Eleven patients had a Kellgren and Lawrence (KL) score of >/=2. A significant association was observed between all patients and meniscal tears (RR 3.57; confidence interval (CI) 1.08-10.0) and meniscal subluxation (RR 2.73; CI 1.20-5.41), between KL < 2 and meniscal subluxation (RR 11.3; CI 2.49-29.49) and KL >/= 2 and meniscus tears (RR 8.91; CI 1.13-22.84) and radiographic JSN 2 years later. Follow-up MR in 15 of 17 patients with progressive JSN showed only new meniscal abnormalities and no progression of cartilage loss. CONCLUSION: Meniscal pathology (tears and/or meniscal subluxation) was the only MRI parameter to be associated with subsequent radiographic progression of JSN in the medial tibiofemoral compartment on a radiograph 2 years later, as assessed by the OARSI score. 相似文献
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Alex D. Federman MD E. Francis Cook ScD Russell S. Phillips MD Ann Louise Puopolo RN BSN Jennifer S. Haas MD MSPH Dr. Troyen A. Brennan MD JD MPH Dr. Helen R. Burstin MD MPH 《Journal of general internal medicine》2001,16(10):668-674
BACKGROUND: Specific elements of health care process and physician behavior have been shown to influence disenrollment decisions in HMOs, but not in outpatient settings caring for patients with diverse types of insurance coverage. OBJECTIVE: To examine whether physician behavior and process of care affect patients' intention to return to their usual health care practice. DESIGN: Cross-sectional patient survey and medical record review. SETTING: Eleven academically affiliated primary care medicine practices in the Boston area. PATIENTS: 2,782 patients with at least one visit in the preceding year. MEASUREMENT: Unwillingness to return to the usual health care practice. RESULTS: Of the 2,782 patients interviewed, 160 (5.8%) indicated they would not be willing to return. Two variables correlated significantly with unwillingness to return after adjustment for demographics, health status, health care utilization, satisfaction with physician's technical skill, site of care, and clustering of patients by provider: dissatisfaction with visit duration (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4 to 7.4) and patient reports that the physician did not listen to what the patient had to say (OR, 8.8; 95% CI, 2.5 to 30.7). In subgroup analysis, patients who were prescribed medications at their last visit but who did not receive an explanation of the purpose of the medication were more likely to be unwilling to return (OR, 4.9; 95% CI, 1.8 to 13.3). CONCLUSION: Failure of physicians to acknowledge patient concerns, provide explanations of care, and spend sufficient time with patients may contribute to patients' decisions to discontinue care at their usual site of care. 相似文献
996.
BACKGROUND: Mohs micrographic surgery is a highly successful technique for removing skin cancers while conserving normal tissue. However, conservation of the deep margins can often be difficult to achieve when using a standard scalpel. An inability to conserve normal tissue at the deep margins can greatly impact the complexity of repair, duration of surgery, aesthetic result, and patient morbidity. OBJECTIVE: To find an alternative method of obtaining Mohs specimens that offers greater control of the depth of incision when compared to the standard scalpel. METHODS: We utilized a flexible scalpel to obtain Mohs levels on patients with superficial cutaneous malignancies in anatomic locations where careful conservation of the deep margins would allow for less extensive repair. RESULTS: For those patients who had tumor-free margins after one level of Mohs surgery, the shallower defects achieved with the flexible scalpel allowed for excellent cosmetic outcomes and decreased patient operative time and morbidity. CONCLUSION: The flexible scalpel is both effective and efficient in obtaining thin Mohs specimens when conservation of the deep margin is of utmost importance. 相似文献
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999.
Lawrence M. Fallat J. Todd Cox Ruby Chahal Pamela Morrison John Kish 《The Journal of foot and ankle surgery》2013,52(3):288-290
Minimally invasive surgery for the treatment of recalcitrant heel pain is a relatively new approach. To compare the 2 approaches, a retrospective chart review was conducted of 53 patients (55 feet) who had undergone surgical treatment of plantar fasciitis by either open fasciotomy with heel spur resection or percutaneous medial fascial release. The outcomes measures included perioperative pain and the interval to return to full activity. Pain was measured on a subjective 10-point visual analog scale. Of the 55 fasciotomies performed, 23 were percutaneous and 32 were open, with adjunctive heel spur resection. The percutaneous group experienced a mean pain reduction of 5.69 points at the first postoperative visit, whereas open fasciotomy group experienced a mean pain reduction of 3.53 points. At 12 months postoperatively, no statistically significant difference was found in the pain levels between the 2 groups. The results also showed that the percutaneous group returned to normal activity an average of 2.82 weeks (p < .001) faster than the open group. In the patient cohorts studied, percutaneous medial fascial release was as effective at resolving recalcitrant plantar fasciitis pain as the open procedure and involved less postoperative pain and a faster return to full activity. 相似文献
1000.