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11.
BACKGROUND: Currently, there are no clear criteria for indicating repeat biopsies in patients with negative results at an initial biopsy of the prostate. The aim of the present study is to determine the clinical and pathological parameters which predict prostate cancer at repeat biopsies with special attention to the interval between biopsies in addition to prostate specific antigen (PSA) and its derivatives. METHODS: We reviewed 100 patients who underwent an initial biopsy that proved negative for prostate cancer and required repeat biopsies between November 1996 and November 2003. Clinical parameters such as age, PSA and its derivatives, interval between biopsies, number of cores taken and initial biopsy histology were analyzed. RESULTS: In total, 31 patients (31.0%) were found to have prostate cancer, 18 (25.7%) of 70 patients by the second biopsy and 13 (46.4%) of 28 patients by the third biopsy. Two patients underwent the fourth biopsy, which revealed no prostate cancer. The patients with a positive biopsy had a significantly longer interval between the biopsies than the patients with a negative biopsy (P=0.0036). Furthermore, in both univariate and multivariate logistic regression analysis, only the interval between the biopsies proved to be an independent predictor of positive results at repeat biopsies (P=0.0094 and 0.0019). CONCLUSIONS: Only the biopsy interval was a significant predictor of prostate cancer at repeat biopsies in both univariate and multivariate analysis.  相似文献   
12.
Aim: Hyaluronan (HA) is an important extracellular matrix (ECM) proteoglycan. The localization of HA and its binding receptors, CD44 and LYVE‐1, was evaluated in an experimental model of chronic cyclosporine A (CsA)‐induced nephropathy. Methods: Sprague–Dawley rats maintained on a low‐salt diet (0.05% sodium) received an s.c. injection of vehicle (1 mL/kg per day olive oil; VH groups) or CsA (15 mg/kg per day; CsA groups) for 1 or 4 weeks. Induction of chronic CsA nephropathy was evaluated according to renal function and pathology and expression of HA, CD44, LYVE‐1, ED‐1 and α‐smooth muscle actin (α‐SMA). Results: CsA treatment for 4 weeks caused renal dysfunction, which was accompanied by typical striped interstitial fibrosis. In the VH group, HA immunoreactivity was observed only in the inner medulla. However, the area of HA immunoreactivity increased with the duration of CsA treatment: CsA treatment for 1 week extended HA immunoreactivity to the outer medulla, and CsA treatment for 4 weeks caused a further extension of HA immunoreactivity to the cortex, which was vulnerable to CsA‐induced renal injury. HA binding receptor, CD44 and LYVE‐1 expression were also upregulated in the CsA groups, and were localized to the area of fibrosis and the peritubular capillaries of the cortex. In the CsA groups, ED‐1 and α‐SMA were predominantly expressed in fibrotic areas in which HA had accumulated. Conclusion: These findings suggest that upregulation of HA and its binding receptors are involved in interstitial fibrosis in chronic CsA‐induced renal injury.  相似文献   
13.
Growth of a hemangiopericytoma in syngeneic (CBA×C57BL/6j)F1 male mice led to regular changes in hematopoiesis: an increase in the weight and number of the spleen cells, an increase in the number of colony-forming units (CFU) in the spleen, intensification of myelopoiesis in the spleen, and the development of leukocytosis with a sharp increase in the number of polymorphonuclear granulocytes in the circulating blood, i.e., a leukemoid reaction syndrome. This syndrome developed also when tumor cells were injected into a splenectomized host. A leukemoid reaction, although less marked, also was found in the late stages of development of a hepatoma, transplanted into syngeneic (CBA×C57BL/6j)F1 male mice. Meanwhile, transplantation of a syngeneic strain of carcinoma of the bladder into the same mice did not lead to the development of a leukemoid reaction.Laboratory of Virology, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 3, pp. 346–349, March, 1978.  相似文献   
14.
In this study, the levels of salivary IgG1, IgG2, IgG3 and IgG4 from individuals with and without homozygous immunoglobulin heavy chain constant gene deletions were quantified by enzyme-linked immunosorbent assay (ELISA). To analyse the restriction of salivary IgG subclasses, we used unstimulated whole saliva and sera collected at the same time from individuals with homozygous gene deletions, two with G1 deletion, one with G4 deletion, six with both G2 and G4 deletions and from eight individuals without IGHG gene deletions and expressing all four IgG subclasses. The median values of salivary IgG from individuals with homozygous G1, or G4, or both G2 and G4 deletions, and from individuals expressing all four subclasses were 24.2 mg/l and 23.4 mg/l, respectively. The median values of serum IgG were 13.7 g/l and 15.9 g/l, respectively. Our results show that the salivary and serum IgG levels were both within the normal range in individuals with homozygous gene deletions of either G1, or G4, or both G2 and G4.  相似文献   
15.
Diospyros fischeri Gurke (Ebenaceae) is used in traditional medicine for the treatment of epilepsy. Dichloromethane, ethylacetate, and ethanol extracts of the roots, at doses between 100 and 1600 mg/kg BW, inhibited convulsions induced by the γ-aminobutyric acid type A (GABAa) receptor antagonist, pentylenetetrazole (PTZ), in a dose dependent manner. The extracts also exhibited low toxicity against brine shrimps giving LC50 values between 45.4 and 95.4 µg/ml. These results provide evidence for the potential of D. fischeri extracts to treat absence seizures, especially given their seemingly innocuous nature.  相似文献   
16.
Administration of a soluble protein into animals prior to challenge immunization induces immunological tolerance which is specific for the protein. In addition, chemical modification of proteins with polyethylene glycol (PEG) has been reported to convert the immunogenic proteins to become tolerogenic. However, differences in tolerogenic properties between PEG-modified proteins and the native counterparts have never been analysed. The ability of PEG-conjugated type II collagen (PEG-CII) to attenuate CIA, an animal model for rheumatoid arthritis, was compared with the native unconjugated CII. Groups of DBA/1 J mice were treated weekly with i.p. injections with PEG-CII, native CII, or vehicle alone for 3 weeks, before they were challenged with CII in adjuvants. The induction of tolerance was confirmed in both PEG-CII- and CII-pretreated mice when suppression of lymph node T cell proliferation in response to CII was noted. The degrees of suppression of T cell proliferation were comparable between the two pretreated groups. However, induction of arthritis and production of IgG anti-CII antibody were more markedly suppressed in PEG-CII-pretreated mice than in native CII-pretreated mice, although the severity of arthritis and antibody levels in the latter group were also lower than in control mice. IgG2a and IgG2b antibody levels were equally suppressed in the two pretreated groups, whereas the IgG1 level was significantly lower in the PEG-CII-pretreated group than in the native CII-pretreated group. The results provide the first evidence that attachment of PEG to CII renders the protein more tolerogenic.  相似文献   
17.
A set of monoclonal antibodies with specificity for hepatitis B surface antigen (HBsAg) was used for subtyping this antigen in sera from indigenous natives, blood donors, and drug users in Western Siberia with a modified commercial enzyme immunoassay kit for HBsAg detection. Three subtypes of HBsAg in a ratio of 36 (78%) ayw2:8 ayw3varB (18%):2 (4%) adw2 were found in 46 (100%) HBsAg-positive sera of different aboriginal populations of Western Siberia: the Tundra Nenets, Northern Khanty, Southern Altaians, and Kazakhs. Four subtypes of HBsAg in a ratio of 81 (57%) ayw2:58 (15 ayw3varA and 43 ayw3varB; 44%):2 (1%) adw2 were detected in 141 (100%) samples of blood donors from ten cities of Western Siberia. Three subtypes of HBsAg in a ratio of 34 ayw3:(both variants, 33 ayw3varA and 1 ayw3varB; 97.1%):1 (2.9%) ayw2 were found in blood of 35 injection drug users in Novosibirsk.  相似文献   
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限制饮食对健康和老化的益处已经逐渐被大家所认识。本文从学习、记忆、突触可塑性、神经再生等神经功能方面,回顾了最近有关限制饮食的基础及临床研究。目前认为限制饮食在神经功能方面发挥多种作用,其中较令人满意的解释是限制饮食作为一种应激原,能诱导机体内有利环境的形成。这个环境有利于促进神经可塑性,提高认知功能,刺激神经细胞再生和调节炎症反应。此外,许多分子包括热休克蛋白、神经营养因子、沉默调节蛋白1(SIRT1)等均参与了限制饮食对机体的保护作用。鉴于完全和长时间的限制饮食在人类实施的困难性,一些限制饮食模型的替代物开始被大家所重视。本文也对限制饮食模型的替代物的研究进行了分析和探讨。  相似文献   
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