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61.
62.
Ghrelin strongly stimulates growth hormone release in humans   总被引:47,自引:0,他引:47  
Ghrelin is a recently identified endogenous ligand for the GH secretagogue receptor and is involved in a novel system for regulating GH release. However, little is known about its GH-releasing activity and other endocrine effects in humans. To address this issue, we studied the GH, ACTH, cortisol, PRL, LH, FSH, and TSH responses to synthetic human ghrelin. In four normal male adults (28-37 yr), iv ghrelin administration released GH in a dose-dependent manner and 0.2, 1.0, and 5.0 microg/kg ghrelin produced 43.3 +/- 6.0, 81.5 +/- 12.7, and 107.0 +/- 10.7 ng/mL of the GH peak values at 30 min, respectively. ACTH, cortisol, and PRL levels were also elevated after ghrelin injection, while the lowest dose (0.2 microg/kg) resulted in only minimum peak values of these hormones (22.8 +/- 3.0 pg/mL, 9.4 +/- 1.9 microg/dL, and 4.6 +/- 0.6 ng/mL, respectively). There were no significant changes in LH, FSH, or TSH levels. This is the first study showing evidence that ghrelin strongly stimulates GH release in humans.  相似文献   
63.
Cells obtained from malignant lymph nodes and the peripheral blood of 106 patients with non-Hodgkin's lymphomas were examined for T- and B-cell characteristics. Surprisingly, 79 cases were of the T-cell type on the basis of spontaneous rosette formation with sheep erythrocytes (E-rosettes). Of the remaining cases, 15 were B-cell in nature (monoclonal S-Ig positive), seven were non T-, non B-cell and four cases were undetermined. Forty-nine (62.0%) of the T-cell malignancies were of a leukemic variety, characterized by pleomorphism in the peripheral blood cell size, and histological appearance. Most of the leukemic T-cells showed obvious lymphocytic differentiation, with condensed nuclear chromatin and scant cytoplasm, although in many of the cases, the lymphomatous infiltrate was dominated by large or pleomorphic lymphoid cells. All tumors were of a diffuse variety, and on histologic examination included a mixed type (21 cases), PDLL forms (15 cases), a large lymphoid cell type (eight cases), and WDLL forms (five cases). Although the mixed type with a pleomorphic lymphoid infiltrate was distinctive, there has been considerable variation from case to case. Clinically this unusual T-cell, leukemic variety of non-Hodgkin's lymphomas primarily involved middle-aged and elderly subjects, and was characterized by wide spread organ invasion (preferentially to the liver, spleen and skin), resistence to chemotherapy, and a poor prognosis. A mediastinal mass was not observed in all cases. The patients had a median survival of only ten months.  相似文献   
64.

Background

This study aimed to determine the radiologic predictors and clarify the clinical features related to survival in patients with combined pulmonary fibrosis and emphysema (CPFE) and lung cancer.

Methods

We retrospectively reviewed the medical chart data and high-resolution computed tomography (HRCT) findings for 81 consecutive patients with CPFE and 92 primary lung cancers (70 men, 11 women; mean age, 70.9 years). We selected 8 axial HRCT images per patient, and visually determined the normal lung, modified Goddard, and fibrosis scores. Multivariate analysis was performed using the Cox proportional hazards regression model.

Results

The major clinical features were a high smoking index of 54.8 pack-years and idiopathic pulmonary fibrosis (n = 44). The major lung cancer profile was a peripherally located squamous cell carcinoma (n = 40) or adenocarcinoma (n = 31) adjacent to emphysema in the upper/middle lobe (n = 27) or fibrosis in the lower lobe (n = 26). The median total normal lung, modified Goddard, and fibrosis scores were 10, 8, and 8, respectively. TNM Classification of malignant tumors (TNM) stage I, II, III, and IV was noted in 37, 7, 26, and 22 patients, respectively. Acute exacerbation occurred in 20 patients. Multivariate analysis showed that a higher normal lung score and TNM stage were independent radiologic and clinical predictors of poor survival at the time of diagnosis of lung cancer.

Conclusions

A markedly reduced area of normal lung on HRCT was a relevant radiologic predictor of survival.  相似文献   
65.
In the management of patients with craniosynostosis, it is important to understand growth curve of the normal cranium. Although three-dimensional (3D) computed tomography (CT) images taken in thin slices are easily available nowadays, data on the growth curves of intracranial volume (ICV), cranial length, cranial width, and cranial height in the normal cranium are mainly based on older studies using radiography, and there are insufficient reports using CT images especially taken in thin slices. The purpose of this study was to establish growth curves in the normal cranium of Japanese children using thin-slice images. Cranial images of 106 subjects (57 males, 49 females; aged 0–83 months) without significant cranial abnormalities were retrospectively analyzed. Using thin-slice CT images, the ICV and two-dimensional parameters such as cranial length, cranial width, and cranial height were measured by iPlan, followed by generating growth curves and calculating cephalic index (CI). ICV calculated from thin-slice CT images was compared with that obtained by substituting two-dimensional parameters into Mackinnon formula. The ICV growth curves for males and females were similar in shape. As with the ICV, the two-dimensional parameters increased most rapidly in the first year after birth. There was no significant difference in CI between the sexes or among any age groups. ICV calculated from thin-slice 3D CT images was 60% of that obtained from Mackinnon formula. These data will enable us to compare these specific measurements in craniosynostosis patients directly with those of normal children, which will hopefully help in managing these patients.  相似文献   
66.
67.
A combination of molecular docking and molecular dynamics simulation (250 ns) has been carried out to study the interaction of stilbenoid trimer compounds with the SIRT1 enzyme as the target protein. SIRT1 expression regulates cellular stress responses that lead to the development of cancer. Redocking showed a good native ligand pose with an RMSD value of 1.40 Å at the receptor active site''s coordinates. The molecular docking score uses a grid score functional (kcal mol−1), which shows results of 1NS: 79.56, TS1: −26.83, TS2: −87.77, and TS3: −83.67. The TS2 and TS3 candidates were chosen for further analysis because they had a lower grid score than the native ligand (1NS). Furthermore, prediction of binding free energy (kcal mol−1) using the Quantum Mechanics/generalized Born Surface Area (QM/MM-GBSA) method shows the results of 1NS: −31.52 ± 0.39, TS2: −58.99 ± 0.34, and TS3: −43.38 ± 0.35. These results indicate that the TS2 and TS3 compounds have good potential as inhibitors of the SIRT1 enzyme. Additionally, the amino acid residues were responsible for the inhibition mechanism through hydrogen bond interactions at the molecular level, including ASP22, PHE91, PRO11, ILE165, ASP166, and VAL230. The observations made in this study provide theoretical information for exploring the stilbenoid trimers as anticancer agents by targeting the SIRT1 enzyme.

A combination of molecular docking and molecular dynamics simulation (250 ns) has been carried out to study the interaction of stilbenoid trimer compounds with the SIRT1 enzyme as the target protein.  相似文献   
68.
69.
We have cloned a pyr4 gene encoding orotidine-5-monophosphate decarboxylase of the filamentous fungus Rhizopus niveus. The pyr4 gene of R. nivens has an open reading frame composed of 265 amino-acid residues and has two putative introns. We have also isolated a pyr4 mutant of Rhizopus delemar from 5-fluoroorotic acid-resistant mutants and transformed it with the pyr4 gene of R. niveus as a selectable marker. Introduced DNA was integrated into the chromosome in a multiple tandem array. The mitotic stability of the introduced DNA was increased by a repeated sporulation process. The expression of the Escherichia coli -glucuronidase gene in R. delemar was successfully obtained under the control of the pgk2 gene promoter of R. niveus by co-transformation with the pyr4 gene.  相似文献   
70.
Purpose Total pelvic exenteration (TPE) is the standard procedure for locally advanced rectal cancer involving the prostate and seminal vesicles. We evaluated the feasibility of bladder-sparing surgery as an alternative to TPE. Methods Eleven patients with advanced primary or recurrent rectal cancer involving the prostate or seminal vesicles, or both, underwent bladder-sparing extended colorectal resection with radical prostatectomy. The procedures performed were abdominoperineal resection (APR) with prostatectomy (n = 6), colorectal resection using intersphincteric resection combined with prostatectomy (n = 4), and abdominoperineal tumor resection with prostatectomy (n = 1). Local control and urinary and anal function were evaluated postoperatively. Results Cysto-urethral anastomosis (CUA) was performed in seven patients and catheter-cystostomy was performed in four patients. Coloanal or colo-anal canal anastomosis was also performed in four patients. There was no mortality, and the morbidity rate was 38%. All patients underwent complete resection with negative surgical margins. After a median follow-up period of 26 months there was no sign of local recurrence, and ten patients were alive without disease, although distant metastases were found in three patients. Five patients had satisfactory voiding function after CUA, and three had satisfactory evacuation after intersphincteric resection (ISR). Conclusion These bladder-sparing procedures allow conservative surgery to be performed in selected patients with advanced rectal cancer involving the prostate or seminal vesicles, without compromising local control.  相似文献   
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