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1.
We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK. We propose that homozygosity for a single mutational event, possibly including contiguous genes, may cause PPK/SCC in both XY or XX individuals and sex reversal in XX individuals. The family is informative for linkage analysis for the PPK trait and allows linkage exclusion for the sex reversal trait. Here we show that 15 loci involved in PPK etiology, skin differentiation, function or malignancy, and nine loci involved in sex determination/differentiation are not implicated in the phenotype of this family.  相似文献   
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The authors sought to determine whether measurement of plasma Müllerian inhibiting substance (MIS) is a suitable substitute for measurement of serum MIS. Eighteen samples of serum and plasma were examined that were drawn simultaneously. Levels of MIS were measured with an ELISA kit, and plasma levels were studied in parallel to serum samples. A 98.5% correlation was found between serum and plasma MIS values.  相似文献   
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BACKGROUND: Jugular vein thrombosis has been reported to occur in pregnant women who conceived with assisted reproductive technology (ART). CASE: A 28-year-old woman at 17 weeks' gestation presented to the emergency room with a syncopal episode. She reported no arm pain or swelling, no neck pain or swelling, and no dyspnea or difficulty swallowing. Doppler sonography of the neck vasculature revealed acute bilateral internal jugular vein thromboses. Thrombophilia workup was normal. Intravenous anticoagulation with heparin was initiated, and the patient was discharged on low-molecular-weight heparin. CONCLUSION: Though rare, jugular vein thrombosis should be considered in the differential diagnosis of syncopal episodes even in women who conceive without ART.  相似文献   
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As surgical weight loss becomes more commonly performed in fertile women, adequate contraception is more frequently becoming an issue. The purpose of this article is to appraise the literature to ascertain whether the use of oral contraception is effective and adequate after bariatric surgery. The literature search revealed that the combination of lower oral contraception dosages and surgical gastrointestinal disturbances might place patients at higher risks of unintended pregnancy. Until clinical trials show its efficacy, physicians should use oral contraception with prudence after bariatric surgery.  相似文献   
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We have shown previously that electrical stimulation of the motor cortex reduces spontaneous painlike behaviors in animals with spinal cord injury (SCI). Because SCI pain behaviors are associated with abnormal inhibition in the inhibitory nucleus zona incerta (ZI) and because inactivation of the ZI blocks motor cortex stimulation (MCS) effects, we hypothesized that the antinociceptive effects of MCS are due to enhanced inhibitory inputs from ZI to the posterior thalamus (Po)—an area heavily implicated in nociceptive processing. To test this hypothesis, we used a rodent model of SCI pain and performed in vivo extracellular electrophysiological recordings in single well-isolated neurons in anesthetized rats. We recorded spontaneous activity in ZI and Po from 48 rats before, during, and after MCS (50 μA, 50 Hz; 300-ms pulses). We found that MCS enhanced spontaneous activity in 35% of ZI neurons and suppressed spontaneous activity in 58% of Po neurons. The majority of MCS-enhanced ZI neurons (81%) were located in the ventrorateral subdivision of ZI—the area containing Po-projecting ZI neurons. In addition, we found that inactivation of ZI using muscimol (GABAA receptor agonist) blocked the effects of MCS in 73% of Po neurons. Although we cannot eliminate the possibility that muscimol spread to areas adjacent to ZI, these findings support our hypothesis and suggest that MCS produces antinociception by activating the incertothalamic pathway.PerspectiveThis article describes a novel brain circuit that can be manipulated, in rats, to produce antinociception. These results have the potential to significantly impact the standard of care currently in place for the treatment of patients with intractable pain.  相似文献   
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A study was carried out to investigate whether testosterone treatment is able to influence tumour growth in a rat prostatic adenocarcinoma previously treated with castration and high-dose fractionated irradiation. Copenhagen × Fisher rats bearing the androgen-sensitive, well-differentiated Dunning R3327-PAP tumour were castrated and thereafter treated with external beam radiation with photons from a 4-MV linear accelerator. One month after irradiation, substitution with subcutaneous testosterone was started. Tumour volumes and rat weights were monitored up to 256 days after castration, and at the end of the study a microscopic analysis of the tumours was performed. Irradiation delayed tumour growth as compared with untreated tumours. Castration delayed tumour growth, but a hormone-refractory relapse to doubled tumour volume was seen within 45 days. If testosterone was added after castration, the tumours grew rapidly. However, testosterone failed to increase tumour growth when given to rats treated with orchiectomy and irradiation. Histological examination showed that the irradiated tumours still contained tumour epithelial cells, but these cells apparently do not respond to testosterone stimulation. The well-differentiated and androgen-sensitive rat prostatic adenocarcinoma did not grow after irradiation despite stimulation with testosterone. This indicates that the malignant cells lose their androgen sensitivity after high-dose irradiation. Received: 7 October 1998 / Accepted: 11 March 1999  相似文献   
10.
Identification of an individual plays a vital part of any medico-legal investigation. Fingerprints are considered to be one of the most reliable methods of identification. The present study was conducted on 752 healthy adult Egyptian subjects (380 males and 372 females) with age ranged from 20 to 30 years. Consents were obtained from all participants and their 10 digits were photographed to determine the sexual dimorphism by some fingertip features (ridge count, square area, finger breadth and finally ridge density) in Egyptians. Statistical analysis was made using a multivariate logistic regression variation analyses. Results showed that females tend to have statistically significant shorter (narrower) finger breadth (right: male > 9.54 ≥ female, left: male > 9.38 ≥ female), smaller square area (right: male ≥ 16.1 > female, left: male > 15.1 ≥ female), more ridge count (right: female > 21.0 ≥ male, left: female > 21.2 ≥ male), and higher ridge density (right: female >1.35 ≥ male, left: female > 1.5 ≥ male) when compared with males. The ridge density of the left hand was the most single accurate parameter in correct sex determination. The best classification accuracy of 82% was generated upon combining ridge count, square area and ridge density. It was concluded that fingertip features of Egyptians can be used by medico-legal experts for accurate sex identification.  相似文献   
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