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71.
BACKGROUND: The complaint of chronic hair loss frequently affects female subjects and there is little or no objective technology available in the general dermatology or even in the hair clinics to guide the observer in the management of the patient. The purpose of this report is to share the results of refined hair growth measurements that were collected in 92 female subjects complaining about hair loss. METHODS: Clinically they were classified as having a patterned hair loss according to Ludwig (L; n=50), diffuse hair loss (D; n=13) or no visible hair loss but complaining of hair shedding (N; n=29). Two scalp sites on the top of the head and one occipital site were investigated after clipping by close-up photography before and after a hair dye (contrast enhancement, CE). Forty-eight hours later a new photograph was taken after CE in view of phototrichogram analysis (CE-PTG). Finally a last hair clip was performed 30 days later and hair thickness and length determined for linear growth measurements (LHGR). RESULTS: Herein we confirm that the top of the head shows usually a higher hair density than occipital sites, a physiological observation that applies both to men and women. From the technological perspective, we also document that CE improves hair detection in all sites. Interestingly, in affected patients (L and D) the relative increase of hair counts after CE was much higher (range +22.4% to +28.3%) compared with apparently unaffected females (N; range +8.2% to +9.7%). This increase in hair counts was only due in part to the presence of less pigmented thinning hair (thickness less than 40 microm). Such thin hairs were found in statistically significantly higher proportions in younger patients with mildly severe (grade I) patterned alopecia (Ludwig: L). In other patients with hair loss and in more severe forms of patterned alopecia - especially in older patients - the thin hair is not detected in abnormal proportions. In all sites slower growth rates and decreased anagen percentages indicate a defective hair replacement programme distinguishing L patterns from diffuse hair loss and from apparently unaffected patients complaining of chronic hair loss. Globally, we also noted that increasing age is associated with significant regression of scalp hair (decreased hair counts, thinner hair and slower LHGR). CONCLUSION: On the basis of the present data together with female data from the literature and our own studies in male subjects, we suggest a three-step mechanism leading to hair loss 1.Shortening of growth phase the hair cycle with maintained thick hair, i.e. more frequent hair cycling that leads to more hair shedding. 2.Intermittent production of short thin hair, i.e. morphological evidence of miniaturisation. 3.Very occasional or almost no hair production, i.e. dormant follicles or irreversible follicular atrophy. Depending on the genetic background, hormonal microenvironment in the scalp and conditioning of individual hair follicle bio-responses, female and male patterned hair loss may end up into different phenotypes.  相似文献   
72.
OBJECTIVE: To describe the dieting histories of bariatric surgery candidates. RESEARCH METHODS AND PROCEDURES: One hundred seventy-seven individuals with extreme obesity who sought bariatric surgery completed the Weight and Lifestyle Inventory, a self-report instrument that assesses several variables, including weight and dieting history. Patients' dieting histories were further explored with an aided recall during a preoperative behavioral/psychological evaluation performed by a mental health professional. RESULTS: Participants who completed the Weight and Lifestyle Inventory reported an average of 4.7 +/- 2.9 successful dieting attempts, defined as those that resulted in a loss of 10 lbs (4.5 kg) or more. These individuals reported a mean total lifetime weight loss of 61.1 +/- 41.3 kg. Despite these efforts, their weight increased from 89.4 +/- 27.4 kg at the time of their first diet (age 21.2 +/- 10.1 years) to 144.5 +/- 30.8 kg at the time they underwent their behavioral/psychological evaluation (age 43.0 +/- 11.0 years). Results of the aided recall revealed that participants had made numerous other efforts to lose weight that were unsuccessful. Self-directed diets and commercial programs were used more frequently. DISCUSSION: Individuals who sought bariatric surgery reported an extensive history of dieting, beginning in adolescence, that was not successful in halting progressive weight gain. Thus, the recommendation often made by insurance companies that patients delay surgery to attempt more conservative treatment options may be unwarranted, particularly in the presence of significant obesity-related comorbidities. Weight loss histories should be routinely examined during a behavioral evaluation to determine whether additional attempts at non-surgical weight loss are advisable. Future studies also are needed to explore the potential relationship between dieting history and postoperative outcome.  相似文献   
73.
探讨keratin 13基因在喉癌发生中的作用。方法在keratin 13基因内部及附近选择5个微卫星引物进行LOH分析,于DNA水平间接检测100例喉癌患者中该基因的缺失情况。结果5个STR位点均存在LOH,其中D17S1964E、D17S2092、D17S791、D17S1665及D17S808位点的LOH频率分别为30.48%、26.02%、21.62%、37.66%和21.51%,以D17S1665位点的LOH频率最高,杂合性丢失与临床分期无显著相关。结论Keratin13基因在喉癌的发生中具有重要作用,具体机制有待进一步研究。  相似文献   
74.
The objective of this study was to report a novel exon-1 mutation in the myelin protein zero (MPZ) gene, resulting in axonal Charcot–Marie–Tooth neuropathy with recurrent hyper-CK-emia. In a 64-year-old woman slowly progressive distal lower limb weakness, muscle cramps in the lower limb muscles, and stocking-type numbness had developed from the age of 61. Neurologic examination revealed discrete hip flexor weakness, weakness for foot extension, diffuse wasting of the distal lower limb muscles, reduced patella tendon reflexes, and absent Achilles tendon reflexes. There was recurrently elevated creatine kinase with a maximum of 607 U/l ( n , <145 U/l). Stimulation of the peroneal and tibial nerves did not evoke a muscular response. Electromyography was neurogenic. Biopsy of the right sural nerve showed diffuse axonal degeneration and loss of axons of all diameters. Muscle biopsy showed increased fiber-size variability, angulated fibers, internalized nuclei, accumulations of nuclei, grouped atrophic muscle fibers, and fiber splitting. Molecular genetic analysis by PCR and direct nucleotide sequencing revealed the heterozygous C59T exon-1 MPZ gene mutation, resulting in the amino acid exchange S20F of the MPZ signal protein domain (leader peptide). The novel C59T mutation in the leader peptide of the MPZ gene is pathogenic and manifests as severe, late-onset, axonal, symmetric sensorimotor polyneuropathy (CMT2) and hyper-CK-emia.  相似文献   
75.
Abstract Although numerous investigators have reported on self-perceived oral health status in adult and older adult populations, few have examined how these perceptions change over time. This paper uses data from a longitudinal oral health survey of community-dwelling Canadians aged 50 years and over to explore this issue. Data were collected at baseline and after 3 years. Change was assessed using a global transition judgement and change scores on four subjective oral health status indicators. These indicators addressed chewing capacity, oral and facial pain symptoms, other oral symptoms, and the psychosocial impact of oral disorders. Overall, 23.0% reported that their oral health had worsened over this period, 66.5% that it had remained the same and 10.5% that it had improved. Change scores on the four indicators showed a similar pattern and were significantly associated with these global judgements. Over the same period, substantial proportions lost one or more teeth, acquired new coronal or root DPS increments or experienced loss of periodontal attachment. An additional 17% complained of dry mouth. However, the only clinical indicator associated with changing perceptions of oral health was tooth loss. Of interest was the fact that rates of tooth loss were equally high among those who reported a worsening of oral health and those who reported an improvement. This suggests that the impact of tooth loss on health status may be positive or negative depending upon the condition of the teeth lost.  相似文献   
76.
PROBLEM: To determine if heparin may act directly with antiphospholipid antibodies (APA) to prevent recurrent pregnancy loss (RPL). METHOD: Patients were seen at the University of Texas Southwestern Medical Center. Twenty women with a history of RPL (≥3 miscarriages), positive APA, and an otherwise normal evaluation were treated with heparin in two daily subcutaneous dosages during a successful pregnancy. APA levels were obtained prior to conception and again at 6, 20, and 30 weeks. RESULTS: Heparin reduced APA binding to cardiolipin and phosphatidylserine in a dose-dependent fashion in ELISA. Heparin affinity chromatography absorbed over 80% of the IgG anticardiolipin antibody in serum from women with high levels of APA. Women treated with increasing dosages of heparin during pregnancy had inversely decreasing levels of IgG anticardiolipin antibody. CONCLUSION: Heparin may act by directly binding APA in vivo, thereby decreasing the adverse effects of APA in women with APA associated RPL.  相似文献   
77.
Abstract A female patient exhibiting functional hearing loss in her left ear demonstrated reduced amplitude of P3 component in event-related potentials (ERP) to left monaural stimulation, with preserved N1 and N2 components to stimulation of either ear. This result suggested that stimuli in the affected ear were conducted successfully up to the auditory cortex but that further processing in higher brain regions was 'repressed'. Event-related potential examination for such hysterical disorders could be useful in clarifying their brain mechanism and offer a useful diagnostic clue to its nature.  相似文献   
78.
A prospective hearing survey was performed in a sample of 102 diabetic patients. The hearing data were compared with the hearing thresholds of three control population groups. A significant difference was found in the average hearing thresholds between the diabetic patients and all of the three control populations. Diabetic patients have worse hearing threshold levels especially at low and mid frequencies (P < 0.001). There was also a correlation between the duration of diabetes and hearing loss. No significant correlation was found between the different stages of diabetic retinopathy and the degree of hearing loss.  相似文献   
79.
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine.  相似文献   
80.
Data from 4,300 consecutive cases following prenatal diagnosis by transcervical (TC) CVS (n = (1,570) and transabdominal (TA) CVS (n = 2,370) were evaluated. In the follow-up study only infants examined by a physician were included. Gestational age varied between 8.5 and 11.6 weeks (mean 10.3 weeks) for TC-CVS and between 9.3 and 20 weeks (mean 12.3 weeks) for TA-CVS 98% of TC-CVS was performed at 9–10 weeks, 80.7% of TA-CVS procedures were carried out at 12–15 weeks. Selective termination took place in 97 cases of TC-CVS (6.1%) and in 72 cases of TA-CVS (2.6%). Another 8 Women had a termination for psychosocial reasons, resulting in 4,123 (1,469 TC, 2,645 TA) continuing pregnancies. The overall fetal loss rare <28 weeks was 5.4% (n = 80) for TC-CVS and 2.6% (n = 70) for TA-CVS. The overall incidence of congenital abnormalities after birth was 0.9%. Two terminal transversal limb defects were detected in the TC-CVS group (0.14%) against one (0.04%) in the TA-CVS group. © 1993 Wiley-Liss, Inc.  相似文献   
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