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71.
Depression is a highly recurrent disorder with significant personal and public health consequences. Prevention of recurrence would be extremely desirable, and thus researchers have begun to identify risk factors that are specific to recurrence, which may be different from risk factors for first onset of depression. Methodological issues in this area of research are briefly reviewed (e.g., the various definitions of "recurrence" and "depression"), followed by a review of studies on specific risk factors, including demographic variables (gender, socio-economic status, and marital status), clinical variables (age at first onset, number of prior episodes, severity of first/index episode, and comorbid psychopathology), family history of psychopathology, and psychosocial and psychological variables (level of psychosocial functioning, cognitions, personality, social support, and stressful life events). In addition, scar theories are evaluated for their potential to explain how these variables and recurrent depression are linked. Our review suggests that recurrent depression reflects an underlying vulnerability that is largely genetic in nature and that may predispose those high in the vulnerability not only to recurrent depressive episodes, but also to the significant psychosocial risk factors that often accompany recurrent depression.  相似文献   
72.
BACKGROUND: In patients with cow's milk protein intolerance (CMPI), delayed clinical reactions to cow's milk (CM) ingestion may be misdiagnosed if the clinical symptoms are not "classical" and there is a long time lapse between ingestion of CM and the clinical reaction. The aim was to evaluate the clinical outcome of CMPI in a cohort of CM-intolerant children, with particular attention to the occurrence of clinical manifestations beyond 72 h after CM challenge. METHODS: Eighty-six consecutive patients (44 boys, 42 girls) with new CMPI diagnoses were enrolled; median age at diagnosis was 4 months. Patients were followed up for a mean period of 40 months. In all patients, CMPI diagnosis was made on the observation of symptoms, their disappearance after elimination diet, and their reappearance on double-blind CM challenge. At CMPI diagnosis, immunologic tests to demonstrate IgE-mediated hypersensitivity were performed. After 12 months of CM-free diet, CM tolerance was re-evaluated with a CM challenge continued at home for up to 30 days, according to a double-blind, placebo-controlled method. Patients who did not achieve CM tolerance continued a CM-free diet and subsequently underwent yearly CM challenge. RESULTS: The percentages of CMPI patients who became CM-tolerant after 1, 2, and 3 years of CM-free diet were 30%, 54.5%, and 70%, respectively. At the end of the follow-up period, 26/86 subjects showed persistent CMPI; these patients had a higher percentage of positivity of total serum IgE (P<0.05), RAST (P<0.01), and cutaneous prick tests for CM antigens (P<0.001) than all the others. At CMPI diagnosis, all patients had a clinical reaction within 72 h from the beginning of the CM challenge; at the subsequent "cure" challenges, we observed patients who first reacted to CM more than 72 h after ingestion. In total, 10 out of 86 patients showed "very delayed reactions"; in these patients, the mean time between the beginning of CM challenge and the onset of a clinical symptom was 13.3 days (range 4-26 days). The number of "very late reactors" increased from the first to the third of the "cure" CM challenges, performed at yearly intervals. The "very delayed" CMPI manifestations in these subjects were constipation (five cases), wheezing (two cases), dermatitis plus constipation (two cases), and dermatitis alone (one case); in 6/10 patients, the symptoms observed at the "cure challenge" were different from those at CMPI onset. CONCLUSIONS: Very delayed clinical reactions to reintroduction of CM in the diet can occur in CMPI patients; thus, accurate follow-up and frequent outpatient observation in patients with a long history of CMPI are probably more useful and safer than prolonged CM challenge.  相似文献   
73.
The Equal Environments Assumption (EEA) in twin studies of eating pathology was investigated by examining the hypothesis that twin resemblance for eating attitudes and behaviors is affected by their degree of physical similarity. Eating attitudes and behaviors were assessed in 338 female adolescent twin pairs with a revised version of the Eating Disorder Inventory (EDI). General physical similarity as well as body size/shape similarity were assessed using ratings of color photographs, ratings of body shape, and body mass index. All physical similarity assessments were conducted blind to twin zygosity. Significant associations between physical similarity and twin similarity for eating attitudes and behaviors were not found. Mean EDI within-twin pair absolute difference scores did not differ significantly among more versus less physically-similar groups. Additionally, correlation and regression analyses failed to find a significant association between EDI absolute difference scores and physical similarity indices. The current findings provide support for the EEA in twin studies of eating attitudes and behaviors.  相似文献   
74.
Genetic and environmental influences on adolescent substance use and abuse   总被引:10,自引:0,他引:10  
The inheritance of substance use and abuse among adolescents was investigated in a sample of 626 male and female 17-year-old twin pairs. Both licit (tobacco) and illicit (e.g., marijuana, amphetamines) substance use and abuse was assessed and analyzed using standard biometric methods. The heritability of use and abuse of illicit substances was modest (25% or less), whereas the heritability of tobacco use and nicotine dependence was substantial (40% to 60%). There was no evidence that gender moderated the strength of genetic influences. Shared environmental influences were substantial for all substance use measures. The finding of greater genetic influence on the use and abuse of a licit substance than on the use and abuse of illicit substances suggests that inherited risk to drug abuse is considerably moderated by environmental control, at least in adolescence. The finding of significant environmental influences on all substance use measures underscores the importance of intervention on early adolescent substance use, a known predictor of adult substance abuse and dependence.  相似文献   
75.
Background: The present study was designed to determine whether exclusion of the gingival connective tissue (CT) and periosteum with contained stem cells has a positive or negative effect on periodontal regeneration by comparing the use of a novel modified perforated collagen membrane with a traditional cell occlusive barrier membrane. Methods: Twenty non‐smoking patients with severe chronic periodontitis were included in the study. Single deep intrabony defects from each of the patients were randomly divided into two groups, as follows: occlusive bovine collagen membranes (OM control group, 10 sites) and modified perforated bovine collagen membranes (MPM test group, 10 sites). Plaque index, gingival index, probing depth (PD), clinical attachment level (CAL), defect base level (DBL), and crestal bone level (CBL) were measured at baseline and were reassessed at 6 and 9 months after therapy to evaluate the quantitative changes in the defect. Results: At 6‐ and 9‐month observation periods, the MPM‐treated sites showed a statistically significant improvement in PD reduction and CAL gain compared with the OM control group. DBL was significantly reduced with no significant difference between the two groups at 6‐ and 9‐month observation periods. CBL was significantly higher in the MPM group when compared with that of the OM group at both observation periods. The postoperative differences between the two groups were 2 and 1.7 mm at 6 and 9 months, respectively, in favor of the MPM‐treated sites. Conclusions: The present study demonstrated enhanced clinical outcomes when using novel MPMs compared to OMs in guided tissue regeneration procedures. These results may be affected by the penetration of gingival CT contained stem cells and periosteal cells and their differentiation into components of the attachment apparatus.  相似文献   
76.
A substantial body of experimental evidence indicates that serotonin (5-HT) and several synthetic 5-HT receptor agonists activate the hypothalamic-pituitary-adrenal (HPA) axis. To explore the mechanism(s) by which 5-HT or 5-HT agonists enhance the activity of the HPA axis in vitro, we examined the stimulatory effects of the 5-HT1a agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), the 5-HT1c/5-HT1b agonist m-chlorophenylpiperazine (m-CPP), and the 5-HT2/5-HT1c agonist 1-(2,5-dimethoxy-4-iodophenyl)2-amino-propane (DOI) on plasma ACTH and corticosterone secretion in the rat. To test whether 8-OH-DPAT, m-CPP, or DOI increase plasma ACTH levels by stimulating the release of endogenous CRH, catheterized conscious male Sprague-Dawley rats were pretreated with hyperimmune CRH rabbit serum (TS-6) or normal rabbit serum and subsequently challenged with a maximally stimulatory dose of the above 5-HT agonists. Pretreatment with TS-6 completely suppressed the ACTH response to m-CPP and significantly blunted the responses to 8-OH-DPAT or DOI. To examine whether the remaining ACTH response to 8-OH-DPAT or DOI was also mediated by a pituitary site of action, we administered each of these agents to pituitary stalk-transected or sham-operated rats. The ACTH responses to 8-OH-DPAT and DOI in stalk-transected rats were preserved, although significantly blunted, compared to those in sham-operated rats. This suggested that both of these 5-HT agonists may also act at the pituitary level to stimulate ACTH release in vivo. Although the ACTH responses to 8-OH-DPAT, m-CPP, and DOI were blunted after both TS-6 pretreatment and pituitary stalk transection, corticosterone responses were only slightly affected, suggesting that some of these compounds may cause corticosterone release in the rat through another mechanism. To evaluate this hypothesis, ACTH and corticosterone responses to 8-OH-DPAT, m-CPP, and DOI were examined in rats whose HPA axis had been suppressed by a single high dose injection of dexamethasone. The corticosterone responses to 8-OH-DPAT and DOI were blunted compared to those of saline-pretreated rats, but were inappropriately high compared to the ACTH responses observed in these rats. On the other hand, both ACTH and corticosterone responses to m-CPP were completely abolished by dexamethasone.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
77.
78.
There is a significant difference in the extent of treatment offered to the elderly with breast cancer; in the United States, while 98% of patients less than 65 years of age receive standard treatment, 81% of those older than 65 years were treated according to protocol. This study's goal was to evaluate disease-specific survival and local-regional recurrence in breast cancer patients more than 65 years of age at diagnosis. A total of 1500 patients with invasive breast carcinoma were treated consecutively from May 1971 to July 2002 at the University of Florence, Florence, Italy. All patients were more than 65 years of age. The median age was 70.6 years (range 65.1-87.3 years).The median follow-up was 8.7 years (range 1-30 years). The crude probability of survival (or relapse occurrence) was estimated using the Kaplan-Meier method and survival (or relapse occurrence) comparisons were carried out using Cox proportional hazard regression models. The Cox regression model by stepwise selection showed as independent prognostic factors for disease-specific survival (DSS), the occurrence of a local relapse (p < 0.0001), pN status (p < 0.0001), the type of surgery (p < 0.0001), and the use of radiotherapy (p < 0.0006) and chemotherapy (p = 0.01). For local disease-free survival (LDFS), the Cox regression model by stepwise selection showed that mastectomy (p < 0.0001), histotype (p < 0.0001), pN status (p < 0.0001), and pT status (p = 0.001) were the only independent prognostic factors. Age was not a prognostic factor for DSS nor LDFS. We suggest treating patients with appropriate treatment for their prognostic factors.  相似文献   
79.
BackgroundPeyonie’s disease (PD) mostly affects males in the fifth decade of life, with a prevalence in the general population ranging between 0.5% and 20.3%. The pathology of PD is characterized by fibrosis of the tunic albuginea of the cavernous bodies of the penis, with the presence of pain in the erection and penile deformity. This is associated with decreased sexual function for both participants. The objective of the study was to investigate the influence of PD pathology on both male patients’ and their female partners’ sexual spheres, and analyze changes in sexual function and perception following penile correction surgery.MethodsProspective study, we included male patients with PD and their female partner sexually active. Patients underwent corporoplasty with multiple plications. The male and female sexuality was evaluated before surgery and three months after male treatment by the Female sexual Function Index (FSFI); International Index of Erectile Function (IIEF); Visual Analogical Scale (VAS).ResultsFrom January 2018 to November 2019 we included 35 couple. The female subjects before partner’s surgery presented dyspareunia, loss of sexual desire, inability to achieve orgasm, and sexual dissatisfaction. At three months after surgical treatment there was an improvement of sexual function in both male patients and female partners (desire P<0.0001, arousal P<0.0001, lubrification P<0.0001, orgasm P<0.0001, satisfaction P<0.0001, pain P<0.0001). As regarding male patients the pain decreased significantly (VAS score from 6 to 2.5), while there was no statistically significant improvement in erectile function (P=0.05).ConclusionsOur findings suggest that a viable approach to treatment of PD patients that involves their partners could lead to better functional and psychological results.  相似文献   
80.

Purpose

Recently, the functional flexion axis has been considered to provide a proper rotational alignment of the femoral component in total knee arthroplasty. Several factors could influence the identification of the functional flexion axis. The purpose of this study was to analyse the estimation of the functional flexion axis by separately focusing on passive flexion and extension movements and specifically assessing its orientation compared to the transepicondylar axis, in both the axial plane and the frontal plane.

Methods

Anatomical and kinematic acquisitions were performed using a commercial navigation system on 79 patients undergoing total knee arthroplasty with cruciate substituting prosthesis design. The functional flexion axis was estimated from passive movements, between 0° and 120° of flexion and back. Intra-observer agreement and reliability, internal–external rotation and the angle with the surgical transepicondylar axis, in axial and frontal planes, were separately analysed for flexion and extension, in pre- and post-implant conditions.

Results

The analysis of reliability and agreement showed good results. The identification of the functional flexion axis showed statistically significant differences both in relation to flexion and extension and to pre- and post-implant conditions, both in frontal plane and in axial plane. The analysis of internal–external rotation confirmed these differences in kinematics (p < 0.05, between 25° and 35° of flexion).

Conclusions

The identification of the functional flexion axis changed in relation to passive flexion and extension movements, above all in frontal plane, while it resulted more stable and reliable in axial plane. These findings supported the possible clinical application of the functional flexion axis in the surgical practice by implementing navigated procedures. However, further analyses are required to better understand the factors affecting the identification of the functional flexion axis.

Level of evidence

IV.
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