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41.
42.
The Raman spectra of solutions of poly(N-vinyl-2-pyrrolidone) (PVP; M?w = 1 000, 10 000, 40 000 and 360 000) in D2O and dimethyl sulfoxide (DMSO) were measured at various concentrations. PVP is hydrated by D2O in a manner different from N-ethyl-2-pyrrolidone (NEP) and N-methyl-2-pyrrolidone (NMP), monomer analogues of PVP. The self-association of DMSO molecules in the solution of PVP was found to be different from that in the solution of NMP by using difference spectroscopy. These phenomena were attributed to a net-like structure of concentrated solutions of PVP.  相似文献   
43.
After serial passage of adenovirus type 12 in cells of the human melanoma line Nki4 virus mutants with enhanced growth potential have been isolated which carry additional sequences of regularly increasing size at the right end of the genome. DNA sequence analysis was performed'to characterize these genomic alterations as well as those of the previously described Ad12 C41 mutants adapted to growth in the human carcinoma cell line C41 (I. Kruczek, E. Schwarz, and H. zur Hausen (1981)Int. J. Cancer27, 139–143). Duplication of the inverted terminal repetition (ITR) emerged as the common feature of the right terminal alterations of all the mutant genomes analyzed. The sequences present between the ITR repeats were of either right-end or left-end origin, the latter suggesting that left-end sequences comprising the ITR and parts of the adjacent unique sequences have been transferred to the right end of the genome. The different sizes of the additional sequences in Ad12 Nki-4 DNA could be explained by varying degrees of amplification of a basic additional sequence of 342 base pairs.  相似文献   
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45.
Islet transplantation is a promising option for the clinical treatment of insulin-dependent diabetes, but a reliable islet cryopreservation/transplantation protocol should be established to overcome the donor shortage. The current study reports that a silk fibroin (SF) sponge disk can be used as a cryodevice for vitrification of large quantity pancreatic islets and the scaffold for subsequent subrenal transplantation in a rat model. The marginal islet mass (550 islet equivalents [IEQs]) on an SF sponge disk was vitrified-warmed and transplanted beneath the kidney capsule of a streptozotocin-induced diabetic rat with or without vascular endothelial growth factor (VEGF). Subrenal transplantation (no scaffold) of 550 IEQ fresh islets and post-warm islets vitrified on a nylon mesh device resulted in achieving euglycemia of recipient rats at 60% and 0%, respectively. Transplantation of 550 IEQ islets vitrified-warmed on an SF sponge disk failed to achieve euglycemia of recipient rats (0%), but the VEGF inclusion in the SF sponge disk contributed to acquiring the euglycemic recipients (33%). All cured recipient rats regained hyperglycemia after nephrectomy, and the histopathologic analysis exhibited a well-developing blood vessel network into the islet engrafts. Thus, an SF sponge disc was successively available as the cryodevice for islet vitrification, the transporter of the angiogenic VEGF, and the scaffold for subrenal transplantation in the rat model.  相似文献   
46.
ObjectivesWe aimed to evaluate the effect of frailty on health-related quality-of-life (HRQOL) and lower urinary symptoms (LUTS) following robot-assisted radical prostatectomy (RARP) in patients with prostate cancer (CaP).Materials and MethodsWe longitudinally evaluated geriatric 8 (G8), HRQOL, and LUTS for 12 months in 118 patients with RARP from January 2017 to April 2020. Patients were divided into frail (G8 ≤14) and nonfrail (G8 >14) groups. We compared the effect of frailty on HRQOL and LUTS between the frail and nonfrail groups before and 12 months after RARP.ResultsThe median age of patients was 68 years. The number of patients in the frail and nonfrail groups were 41 and 77, respectively. No significant difference in patients’ background was observed between the groups, except for the presence of cardiovascular disease (22% vs. 7.8%, P = 0.041). There was no significant difference in HRQOLs and LUTS between the groups at baseline. Similarly, HRQOLs, LUTS, and pad-free continence rates were not significantly different between the groups at 12 months after RARP. In the nonfrail group, LUTS at 12 months following RARP significantly improved compared to those at the baseline, but it did not significantly improve in the frail group. Multivariable logistic regression analysis demonstrated that frailty was not significantly associated with LUTS worsening.ConclusionsFrailty was not significantly associated with the worsening of HRQOL, LUTS, and pad-free continence rates in patients treated with RARP.  相似文献   
47.
ObjectivesTo investigate the association between Ki67 index and programmed death-ligand 1 (PD-L1) expression in muscle-invasive bladder cancer (MIBC) patients after RC.Materials and MethodsWe retrospectively evaluated 262 MIBC patients treated with RC between April 2004 and April 2020. The impact of Ki67 index and PD-L1 expression on prognosis was evaluated by univariate Cox regression analysis. In addition, a pathomolecular risk score, including Ki67 and PD-L1, was developed to predict prognosis and pathological factors. We also evaluated the link between the Ki67 index and PD-L1 under the IL-6 stimulation in the bladder cancer cell lines of T24 and 5637 cells.ResultsThe median age and follow-up period was 69 years and 52 months, respectively. Ki67 index and PD-L1 expression were significantly associated with tumor recurrence. Univariate Cox regression analysis showed that pT3–4, mixed histology, lymphovascular invasion positive (LVI+), pN+, Ki67-high (>17%), and PD-L1+ were significantly associated with recurrence-free survival (RFS). The pathomolecular risk score was developed using resection margin+ (1 point), mixed histology (1 point), LVI+ (1 point), pN+ (1 point), and Ki67-high (1 point). RFS and overall survival were significantly shorter in patients with higher pathomolecular risk scores (>1) than in those with lower risk scores (≤1). Cell proliferation was significantly increased in the T24 and 5637 cells under the IL-6 stimulation, while PD-L1 expression was not.ConclusionsA significant effect of Ki67-high and PD-L1 expression on poor prognosis was observed in patients with MIBC. Further studies are necessary to elucidate the precise mechanisms of cell proliferation and PD-L1 expression in patients with MIBC.  相似文献   
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49.
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent.  相似文献   
50.

Purpose

It is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seem to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.

Materials and Methods

Isometric tension measurement with cavernous strips was performed in the presence or absence of 10 sup -5 to 10 sup -9 M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.

Results

Both PRL and GH produced dose-related elevations (p less than 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p greater than 0.05). When the tension rise produced by 120 mEq KCl was taken as 100 percent, the maximum contractions produced by PRL and GH were 80 percent and 110 percent. The minimum effective concentration was 10 sup -8 to 10 sup -7 M. for both PRL and GH. Pretreatment with indomethacin (10 sup -5 M.), but not tetrodotoxin (10 sup -5 M.), partially suppressed (p less than 0.05) the effects of PRL.

Conclusion

These results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.  相似文献   
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