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991.
Micronodular basal cell carcinoma (BCC) may be more difficult to eradicate and prone to recurrence than nodular subtype. The aim of the study was to compare anatomical and histological characteristics of the basal cell carcinomas subtypes and the relationship of the micronodular BCC with other subtypes. Primary BCCs (n = 3074) were classified as superficial, nodular, micronodular, morpheic/infiltrative. The location was head/neck, limbs, chest/abdomen, back or genitals. Fifty‐one micronodular BCCs were matched randomly with nodular and infiltrative cases, by age, sex, and tumor site. A modified Clark level was used to classify the tumor depth. Micronodular, nodular and infiltrative BCC were prevalently located in the head/neck (P < 0.0001), while superficial in the other regions (P < 0.0001). The Clark level was comparable between micronodular and infiltrative BCC, while nodular BCC showed a more superficial level than micronodular (P < 0.001) and infiltrative (P < 0.001) BCC. No nodular BCC had level IV and only 37.3% level III, while 92% of both micronodular and infiltrative BCC were level III or IV. The percentage of level IV was 11.8% and 25.5% in micronodular and infiltrative BCC, respectively. In the mid‐face/periauricular region, 95.5% of micronodular and 100% of infiltrative cases of were level III or IV, compared to 50% of nodular BCC (P < 0.001). The Clark level of nodular subtype was higher for BCC of mid‐face/periauricular than other regions (P < 0.05). It can be concluded that micronodular BCC shows intermediate characteristics compared with nodular and infiltrative subtypes but appears to have a specific individuality making it a distinct subtype.  相似文献   
992.
The objective of this study was to evaluate the relationship between REM sleep behavior disorder (RBD), hallucinations, and cognitive impairment in Parkinson's disease (PD). One hundred and ten PD patients, divided into three groups (without RBD or hallucinations; with RBD but no hallucinations; with RBD and hallucinations), were submitted to neuropsychological evaluation. The group without RBD and hallucinations showed normal neuropsychological tests when compared to normal controls. The group with hallucinations was characterized by a more severe cognitive impairment affecting both short- and long-term memory, logical abilities, and frontal functions, while the RBD-only group presented frontal impairment. The hypothesis that RBD in PD can be considered a risk factor not only of the hallucinations but also of more severe and diffuse cognitive abnormalities needs to be strengthened through a longitudinal evaluation.  相似文献   
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994.
In the past two decades, growth hormone (GH) has been considered as a performance-enhancing drug in the sport world, certainly favoured by the awareness that there is not yet an approved method for detecting its abuse. Because resting or random measurements of plasma GH concentrations per se are meaningless, new methods have been devised to evaluate plasma levels of GH-sensitive substances that are more stable, and hence detectable, than the hormone itself. This review discusses some of the most recently proposed approaches, including a diagnostic algorithm, based on the timed application of different tests, which, collectively, would have a high diagnostic capability.  相似文献   
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996.

Background  

Carcinosarcoma of the colon is a rare histopathological entity with uncertain histogenesis, that shows both epithelial and mesenchymal malignant differentiation. Carcinosarcoma rarely affects the gastrointestinal tract and only few cases are reported in the colon. Herein we describe a carcinosarcoma of the ascending colon, with morphological, ultrastructural and molecular analysis.  相似文献   
997.
The ISCD recommends that bone mineral density (BMD) be monitored in patients undergoing antiresorptive therapy to identify patients with a significant BMD loss. This analysis compares the proportions of postmenopausal women treated with raloxifene 60 mg/d (n=82) or alendronate 10 mg/d (n=83) who had significant BMD loss in a randomized, double-blind, placebo-controlled trial that assessed changes in lumbar spine and femoral neck BMD from baseline to 1 yr, measured using dual-energy X-ray absorptiometry. According to ISCD criteria, significant BMD loss was defined as greater than the least significant change, calculated as precision multiplied by 2.77 (95% confidence interval). Assuming a 1% precision at the lumbar spine, the proportions of women with a loss of BMD greater than the least significant change (3%) were similar (p>0.05) between the raloxifene (3%) and alendronate (2%) groups. Assuming 2% precision at the femoral neck, the proportions of women with a loss greater than the least significant change (6%) were similar (p>0.05) between the raloxifene (1%) and alendronate (2%) groups. In conclusion, similar proportions of women did not respond to raloxifene or alendronate therapy, as measured by changes in lumbar spine or femoral neck BMD, when precision error was taken into account.  相似文献   
998.
Deficiency of 17beta-hydroxysteroid dehydrogenase type 3 (17beta-HSD3), due to mutations in the gene encoding the enzyme, results in a rare autosomal recessive form of male-to-female sex reversal. Mutated genes encode an abnormal enzyme with absent or reduced ability to convert Delta4-androstenedione to testosterone in the testis. Affected individuals are genetically males who developed internal male Wolffian structures but female external genitalia. Such individuals are usually raised as females and diagnosis is made at puberty, when they show virilization. Correct diagnosis is mandatory to optimize treatment and follow-up. In the present paper we report the clinical history, endocrine evaluation and molecular genetics of a prepubertal girl affected by 17beta-HSD3 deficiency, in whom an erroneous diagnosis of androgen insensitivity syndrome was made. The clinical, endocrine and genetic features of 17beta-HSD3 deficiency are also reviewed.  相似文献   
999.
Athletic training in adolescent females is important for their well-being; indeed, it may have both positive and negative effects on some physiological processes, as growth, reproductive axis and bone health. Adequate physical activity likely exerts neither a positive nor a negative effect on growth. By contrast, intensive training and insufficient diet may have a negative influence on growth, probably due to energy deficiency and impairment of the growth hormone-insulin-like growth factor-I axis; net long term-effects of such alterations remain to be established. Adolescents who perform regular athletic training present with normal or slightly advanced sexual maturation, because increased strength and power associated with earlier maturation advantage them. However, intensive training and inadequate energy intake may induce delayed menarche and menstrual dysfunctions. The consequent hypoestrogenism, in association with the nutritional deficiencies, may affect bone health. On the contrary, regular physical activity increases the amount of bone mass gained during childhood and adolescence mainly at the bone sites which are trained. Since the number of adolescent females involved in strenuous sports from an early age is increasing, physicians must be aware of such effects, explain to girls and their parents the 'right' sports training and appropriate dietary regimens, and recognize problems due to excessive training as soon as possible. These issues should not be a cause of lesser involvement in athletic participation of young people.  相似文献   
1000.
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