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991.
A mouse monoclonal antibody against the N-terminal region of human androgen receptor (AR) was used to identify receptors by immunoperoxidase staining in frozen serial sections of skin from scalp, face, limb and genitalia of men and women aged 30-80 years. AR staining was restricted to cell nuclei. In sebaceous glands, AR were identified in basal and differentiating sebocytes. The percentage of receptor-positive basal sebocyte nuclei in the temple/forehead region was greater in males (65%) than in females (29%). AR staining was restricted to the cells of dermal papillae in anagen and telogen hair follicles. The percentage of dermal papillae containing AR was greater in males (58%) than in females (20%). The number of positively stained dermal papillae was lowest in female scalp skin. In 163 hair follicles sectioned, AR were absent from germinative matrix, outer root sheath (including the bulge region), inner root sheath, hair shaft and hair bulb, and from the capillaries present in some large dermal papillae. AR were present in pilosebaceous duct keratinocytes, suggesting that androgens may influence pilosebaceous duct keratinization. AR were also identified in interfollicular epidermal keratinocytes and dermal fibroblasts although, in both cell types, intensity and frequency of staining were greatest in genital skin. AR were identified in luminal epithelial cells of apocrine glands in genital skin and in certain cells of the secretory coils of eccrine sweat glands in all body sites. This study indicates that androgens regulate sebaceous gland and hair growth by acting upon two different types of target cells, the epithelial sebocytes of sebaceous glands and the mesenchymal cells of the hair follicle dermal papilla.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BackgroundCorticosteroids are an integral part of immunosuppression following solid organ transplantation, despite their metabolic complications. We conducted a randomized trial to evaluate the efficacy of steroid-free immunosuppression following live donor liver transplantation (LDLT).MethodsWe randomized 104 patients stratified based on pre-transplant diabetic status to either a steroid-free arm (SF-arm) (Basiliximab + Tacrolimus and Azathioprine,n = 52) or Steroid arm (S-Arm) (Steroid + Tacrolimus + Azathioprine,n = 52). The primary endpoint was the occurrence of metabolic complications (new-onset diabetes after transplant (NODAT), new-onset systemic hypertension after transplant (NOSHT), post-transplant dyslipidemia) within 6 months after transplant. Secondary endpoints included biopsy-proven acute rejection (BPAR) within six months, patient and graft survival at 6 months.ResultsThe incidence NODAT was significantly higher in S-arm at 3 months (64.5%vs. 28.1%,p-0.004) and 6 months (51.6% vs. 15.6%,p-0.006). Likewise, the incidence of NOSHT (27.8% vs. 4.8%,p-0.01) and hypertriglyceridemia (26.7% vs. 8%,p-0.03) at six months was significantly higher in S-arm. However, there were no differences in BPAR (19.2% vs. 21.2%, p-0.81), time to first rejection (58 vs. 53 days, p-0.78), patient and graft survival (610 vs. 554 days,p- 0.22).ConclusionFollowing LDLT, basiliximab induction with tacrolimus and azathioprine maintenance resulted in significantly lower metabolic complications compared to the triple-drug regimen of steroid, tacrolimus, and azathioprine.  相似文献   
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Background: Accurate measurement of polyp size during colonoscopy is important because of the direct correlation of size with colon cancer. Major studies of colorectal neoplasms have measured polyp size differently. It is also well documented that endoscopists underestimate polyp size frequently. The goal of this prospective study was to determine which one of the five methods of estimating polyp size during colonoscopy is most accurate. Methods: One hundred colon polyps were measured by means of visual estimation, open biopsy forceps methods, linear probe, a ruler immediately after excision, and after fixation in formalin. The size of the polyps measured outside the body immediately after excision was considered the “gold standard” against which all measurements were compared. Results: Forty-seven polyps were 5 mm or less in diameter, 33 polyps were 5.01 mm to 10 mm, and 20 polyps were more than 10 mm in size. For all polyps the mean difference versus the actual size of the polyps was 3.4% for linear probe, 6.4% for visual estimation, and 12.3% for the forceps. Conclusion: Measurement of polyp size by linear probe agreed best with the actual polyp size, followed closely by visual estimation. The open biopsy forceps method was the least accurate. (Gastrointest Endosc 1997;46:497-502.)  相似文献   
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Introduction

The purpose of this study was to analyze the relation of tooth length and distal wall thickness of mesial roots in mandibular molars at different locations (ie, 2 mm below the furcation and at the junction between the middle and apical third).

Methods

Forty-five mandibular first molars were taken, and the length of each tooth was measured. Then, specimens were divided into three groups according to their length: group I–long (24.2 mm ± 1.8), group II–medium (21 mm ± 1.5) and group III–short (16.8 mm ± 1.8). mesial root of each marked at two levels - at 2 mm below the furcation as well as at junction of apical and middle third of roots. The minimum thickness of the distal root dentine associated with the buccal and lingual canals of the mesial roots was measured, The distance between the buccal and lingual canals and the depth of concavity in the distal surface of the mesial roots were also measured.

Results

Statistical analysis was performed by using analysis of variance and the Student-Newman-Keuls test. The minimum thickness of the distal wall of the mesiobuccal canal was significantly different (P < .001) between groups 1 (long) and 3 (short).

Conclusions

Distal wall thickness of the mesiobuccal root and distal concavity of the mesial root of mandibular first molars were found to be thinner in longer teeth compared with shorter teeth.  相似文献   
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