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991.
Investigations of breast carcinogenesis often rely upon comparisons between cancer tissue and nonmalignant breast tissue. It is unclear how well common reference sources of nonmalignant breast tissues reflect normal breast tissue. Breast tissue samples were evaluated from three sources: (1) normal donor tissues in the Susan G. Komen for the Cure Tissue Bank at Indiana University Simon Cancer Center (KTB), (2) women who underwent reduction mammaplasty (RM) at Mayo Clinic Rochester, and (3) the Mayo Clinic Benign Breast Disease Cohort Study (BBD). Samples were examined histologically and assessed for proliferative disease and degree of lobular involution. Univariate comparisons were performed among the study groups, and multivariate analyses were performed with logistic regression to assess the association between study group and the presence of epithelial proliferative disease and complete lobular involution. Histologic data were collected for 455 KTB samples, 259 RM samples, and 319 BBD samples. Histologic findings and the frequency of epithelial proliferation were significantly different among the groups. Histologic abnormalities were seen in a minority of the KTB samples (35%), whereas an abnormality was present in 88% of RM tissues and 97.5% of BBD samples. The presence of proliferative disease (with or without atypical hyperplasia) was present in 3.3% of normal donors (3.3%), 17% of RM samples, and 34.9% of BBD samples (P < 0.0001 for each comparison). Multivariate analyses confirmed that these differences remained significant and also showed higher likelihood of complete lobular involution in the normal donor samples compared to RM and BBD tissues. Compared to benign breast disease tissues and reduction mammaplasty tissues, breast tissue samples from normal donors have significantly fewer histologic abnormalities and a higher frequency of more complete lobular involution. Breast tissue samples from normal donors represent a unique tissue resource with histologic features consistent with lower breast cancer risk.  相似文献   
992.
AIM: There are few data on seasonal variation in stroke and seasonal variation in mortality after stroke in patients with atrial fibrillation. We examined the seasonal pattern in stroke occurrence and the effect of the season on mortality after stroke in patients with a history of nonvalvular atrial fibrillation. METHODS: We identified all individuals, aged 40-89 years, with an incident diagnosis of stroke of any nature (ischemic or hemorrhagic) in the 1980-2002 period and no history of heart valve disease and a previous or concomitant diagnosis of atrial fibrillation or flutter in the Danish National Registry of Patients. Subjects were followed in the Danish Civil Registration System for emigration and vital status. We used periodic regression models to estimate the peak-trough ratio stratified by sex, age and comorbid medical conditions. Seasonal effect on mortality after stroke was analyzed in a Cox proportional hazards model. RESULTS: The relative incidence of stroke estimated as the ratio of the incidence in the month of the peak (January) to the incidence in the month of the trough (July) was 1.11 (95% confidence interval: 1.07-1.15). The relative incidence of stroke was similar for men and women, did not differ by age (stratified by age 75 years) and was essentially similar for comorbid conditions considered. There was no seasonal effect on mortality after stroke. CONCLUSIONS: The occurrence of stroke in patients with atrial fibrillation is modestly higher during the winter. Stroke-associated mortality does not vary by season.  相似文献   
993.
A retrospective review was performed of all osteochondroma excisions at our institution from 1994 to 2007. Postoperative functional assessment was completed with use of the Disabilities of the Arm, Shoulder and Hand (DASH) survey and a self-report questionnaire. Eight osteochondromas were excised at a mean patient age of 21.63 years. Presenting reports included pain, mass, pseudowinging, and snapping of the scapula. Physical examination identified pseudowinging, palpable mass, and pain with shoulder motion. The lesions arose from the ventral surface of the scapula in 5 patients, the dorsal surface in 2, and the inferior acromion in 1. The resected specimen averaged 10.8cm(3). A reactive bursa was found and resected in 4 patients. At mean of 4.17 years postresection, no signs of recurrence were found in 7 patients (88%). The single patient with a recurrence had undergone 2 additional surgical procedures. Six patients (75%) reported no/mild pain with routine and strenuous activities. One patient reported moderate and 1 patient reported moderate/severe pain with routine and strenuous activities. Four patients reported post-resection function as excellent, 2 as good, 1 as average/good, and 1 as average/poor. Six patients (75%) reported feeling very satisfied with the results, 1 reported feeling satisfied, and 1 reported feeling unsatisfied. The average DASH score was 11.7 (range, 0.00-46.67). No winging or pseudowinging was identified in those available for examination, and no difference was identified in range of motion comparing the operative to the nonoperative upper extremity. Near normal functional outcomes can be expected following excision of scapular osteochondromas.  相似文献   
994.
目的:探讨腹腔镜胆囊切除术(LC)与开腹胆囊切除术(OC)对伴有肥胖病人的效果对比,确定手术原则。方法:对87例伴有肥胖症行腹腔镜胆囊切除术或开腹胆囊切除术病人,统计术中、术后一般情况及术后并发症,分为LC组和OC组进行对比。结果:LC组术中、术后一般情况中大部分指标以及术后并发症发生率指标都优于OC组。结论:在充分的术前准备和丰富的手术经验前提下,对一般肥胖患者实施胆囊切除术首选LC。  相似文献   
995.
996.
目的:评估各种尿道修复术式在不同程度后尿道狭窄中的运用及治疗效果。方法:从1997年1月~2006年12月共有296例外伤性骨盆骨折导致的后尿道狭窄患者接受后尿道端端吻合术,其中单纯端端吻合70例(Ⅰ组);阴茎海绵体中隔切开结合端端吻合70例(Ⅱ组);海绵体中隔+耻骨下缘切除结合端端吻合154例(Ⅲ组);耻骨下缘切除+尿道从一侧阴茎海绵体旁绕结合端端吻合2例(Ⅳ组)。结果:296例后尿道端端吻合术中,254例成功,42例失败。Ⅰ组成功率78.6%,Ⅱ组成功率90.0%,Ⅲ组成功率88.3%,Ⅳ组成功率为0。结论:经会阴途径的不同辅助手术方法可有效地治疗后尿道狭窄。  相似文献   
997.
目的:提高对阴茎头硬化性苔藓样变(LS)及由此引起的前尿道狭窄的认识,并探讨合理的手术治疗方法。方法:15例LS并发前尿道狭窄的患者,年龄27~75岁,尿道狭窄段长4~16cm。采用舌黏膜尿道成形11例、结肠黏膜尿道成形2例;尿道外口切开及前尿道劈开术各1例。所有患者手术同时行LS病变组织病理学检查。结果:术后随访6~12个月(平均10.07个月)。1例游离结肠黏膜尿道成形患者术后2月发生尿道外口狭窄。行尿道外口切开后排尿道通畅;余者术后排尿通畅,Qmax:17.2~32ml/s(平均18.70ml/s)。结论:采用游离黏膜尿道成形治疗LS性尿道狭窄可取得较好效果,但需密切随访病变迁延致尿道再狭窄。  相似文献   
998.
Direct measurement of neuropeptides in the hypothalamus is essential for neuroendocrine studies. However, the small quantities of peptides released at their neuroterminals and relatively large molecular sizes make these measurements difficult. We have evaluated microdialysis probes with two membrane materials (polycarbonate and polyarylethersulfone, both: molecular cut off 20,000 Da) in vitro, and adapted the method for in vivo hypothalamic sample collection in non-human primates. The results of in vitro experiments showed that the polyarylethersulfone membrane yielded a several fold higher recovery rate than the polycarbonate membrane. In in vivo experiments, a guide cannula with stylet was inserted into the medial basal hypothalamus through the permanently implanted cranial pedestal under light sedation. The stylet was replaced by a microdialysis probe and artificial CSF was infused. The results indicated that the neuropeptide luteinizing hormone-releasing hormone was readily measurable in dialysates collected at 10 min-intervals, and responded to neuroactive substances applied through the probe. The animals were fully conscious except for the initial hour of sampling. After the experiment the animal was returned to the home cage, and later similarly examined during several additional experiments. Therefore, the microdialysis method described here is a highly useful tool for neuroendocrine studies in non-human primates.  相似文献   
999.
The aim of the present study was to determine the economic and social burden of compulsive hoarding in a large sample of individuals with self-identified hoarding, as well as a separate sample of family members of individuals who hoard. Self-identified hoarding participants (N=864, 94% female, 65% met research criteria for clinically relevant compulsive hoarding) and family informants (N=655, 58% described a relative who appeared to meet research criteria for compulsive hoarding), completed an internet survey. Questions were derived in part from those used in the National Comorbidity Survey (NCS), and when possible, hoarding participants were compared to NCS participants. Compulsive hoarding was associated with an average 7.0 work impairment days in the past month, equivalent to that reported by individuals with psychotic disorders and significantly greater than that reported by female NCS participants with all other anxiety, mood, and substance use disorders. Severity of hoarding predicted the degree of work impairment after controlling for age, sex, and non-psychiatric medical conditions. Hoarding participants were nearly three times as likely to be overweight or obese as were family members. Compared to female NCS participants, hoarding participants were significantly more likely to report a broad range of chronic and severe medical concerns and had a five-fold higher rate of mental health service utilization. Eight to 12% had been evicted or threatened with eviction due to hoarding, and 0.1-3.0% had a child or elder removed from the home. These results suggest that compulsive hoarding represents a profound public health burden in terms of occupational impairment, poor physical health, and social service involvement.  相似文献   
1000.
Summary. Lithium and valproate are the prototypic mood stabilizers and have diverse structures and targets. Both drugs influence inositol metabolism. Lithium inhibits IMPase and valproate inhibits MIP synthase. This study shows that MIP synthase inhibition does not replicate or augment the effects of lithium in the inositol sensitive pilocarpine-induced seizures model. This lack of effects may stem from the low contribution of de-novo synthesis to cellular inositol supply or to the inhibition of the de-novo synthesis by lithium itself. Correspondence: Haim Einat, 376 Kirby Plaza, 1208 Kirby Drive, Duluth, MN 55812, USA  相似文献   
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