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51.
Vitamin D3, having gained scientific interest for so long because of its role in mineral homeostasis, has now received great importance as a possible antitumor agent. This study was undertaken in an attempt to visualize the possible anticlastogenic potential of the vitamin in an ascitic mouse lymphoma model namely, Dalton's lymphoma. Frequencies of structural type chromosomal aberrations, sister chromatid exchanges and micronucleus assays have been chosen as the genotoxic endpoints in the proposed investigation. All these cytogenetic markers have been found to be markedly elevated during the progression of lymphoma in bone marrow cells. Vitamin D3 effectively suppressed the frequencies of chromosomal aberrations and sister chromatid exchanges in the lymphoma-bearing mice during the entire phase of tumor growth that significantly coupled with almost two-fold increase in survival time (37 +/- 2 and 68 +/- 2 days in lymphoma controls and vitamin D3-treated lymphoma-bearing mice, respectively), thus substantiating the antineoplastic efficacy of this secosteroid. The outcome of this study also is clearly reflected in the depletion of circulating (serum) vitamin D3 levels in the lymphoma control mice compared with normal (vehicle) controls while a still higher level was maintained in the VD3-treated lymphoma mice. This anticlastogenic property of the vitamin has so far been neglected and this is the first attempt to unravel the vitamin D3's effect in combating tumor development in vivo by limiting the frequencies of chromosomal aberrations, sister chromatid exchanges and micronuclei at least in transplantable murine model studied herein.  相似文献   
52.

Research question

Are high-responder IVF patients protected from the deleterious effect of prematurely elevated serum progesterone level on the probability of pregnancy?

Design

In this retrospective cohort study, 2971 autologous fresh embryo transfer IVF cycles with gonadotrophin-releasing hormone agonist long protocol were analysed to investigate whether the detrimental effect of prematurely rising progesterone levels on clinical pregnancy rate (CPR) varies depending on the magnitude of ovarian response. Nine different evenly spaced intervals were constructed for serum progesterone level on the human chorionic gonadotrophin day (<0.5/0.5–0.9/1–1.4/1.5–1.9/2–2.4/2.5–2.9/3–3.4/3.5–3.9/>4 ng/ml). Then, IVF cycles in each of these intervals were further divided into low (≤3 oocytes), normal (4–15 oocytes) and high responders (≥16 oocytes).

Results

The progressive rise of serum progesterone from the <0.5 to the >4 ng/ml interval caused a gradual and continuous decline in the CPR of all three types of ovarian response. The absolute difference in the CPR between the lowest and the highest progesterone groups was not related to the magnitude of ovarian response (–26.6%, –37.7% and –40.7% for the low, normal and high responders, respectively). On multivariate logistic regression analysis, the detrimental effect of progesterone started at 1.5–1.9 ng/ml, 3.0–3.4 ng/ml and 4.0–4.4 ng/ml intervals for the low, normal and high responders, respectively.

Conclusion

High responders are not exempt from the detrimental effects of prematurely rising serum progesterone levels but the threshold interval where the detrimental effect begins is higher in the high responders compared with the low and normal responders.  相似文献   
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Bovine lens aldose reductase, an enzyme important in sugar cataract formation, has been purified using a new procedure, and its optimum conditions of assay defined in both lens homogenates and purified preparations. Preliminary kinetic analysis shows that the degree of the rate equation is of a low order, and may be Michaelian under the standard conditions used.  相似文献   
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BACKGROUND: Intestinal milking is a frequently used method in abdominal surgery for various purposes; although it is frequently used for eliminating distension, moving faeces, bezoar or other foreign objects proximal or distal, there are no experimental or prospective studies in the surgical literature with respect to complications of the method. The purpose of the present study was to investigate complications of the milking process in an experimental model. METHODS: Forty-four outbred, 8-month old Wistar albino male rats with weights ranging between 195 and 225 g were used. Four rats were used for preliminary study. The other 40 rats were divided into two equal groups. In the study group (n = 20), a plastic sphere, 3 mm in diameter was sent to the stomach via oro-gastric tubes. This sphere was then moved into the cecum by milking. In the control group rats (n = 20) the small intestines were manipulated at 1-cm intervals but milking was not performed. RESULTS: In the study group six rats (30%) developed grade 1, 11 rats (55%) developed grade 2, and three rats (15%) developed grade 3 peritoneal adhesion. In the control group, 18 rats (90%) had no adhesions and only two rats (10%) developed grade 1 adhesion (chi(2) = 34, P < 0.0001). In the study group, four rats (20%) had small bowel obstruction, whereas no rats in the control group developed small bowel obstruction (Fisher's P > 0.05). Peritoneal smear culture was positive in 11 rats (55%) in the study group, whereas it was positive in two rats (10%) in the control group (Fisher's P < 0.01). CONCLUSIONS: Intestinal milking is a process that can cause severe peritoneal adhesions and peritoneal contamination, which may lead to small bowel obstruction. Avoiding milking to the extent possible in eliminating distension intraluminal material that may cause obstruction, and preferring alternative methods is important for reducing postoperative morbidity.  相似文献   
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Background Immune dysregulation has been shown to be one of the major aspects of the yet unknown pathogenesis of Behçet's disease. Interleukin-8 (IL-8), a major chemokine with pivotal effects concerning leukocytes and endothelial cells, has been found to be elevated in patients with Behçet's disease. Aim To evaluate the significance of elevated levels of IL-8 with respect to the activity of Behçet's disease. Methods Sixty-seven consecutive patients with Behçet's disease (37 males, 30 females; 32.5 ± 9.3 years) were enrolled in our study. The number of active clinical manifestations at the time of serum sampling was recorded. The degree of association between disease activity and IL-8, C-reactive protein, and erythrocyte sedimentation rate was assessed. Results Serum levels of IL-8 increased as the number of clinically involved organs increased (P < 0.05). C-reactive protein and the erythrocyte sedimentation rate showed no correlation with disease activity. Conclusions Our study confirms that the IL-8 level is a more sensitive marker of disease activity than the erythrocyte sedimentation rate and C-reactive protein. It may be assumed that IL-8 plays an important role in the pathophysiology of Behçet's disease.  相似文献   
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OBJECTIVE: To determine the distribution of 1,25-dihydroxyvitamin D receptor (VDR) in rat vaginal epithelium during the estrus cycle and in ovariectomized rats. DESIGN: Animal study performed in two groups of rats. The expression of VDR was examined in the first group during the estrous cycle and in the second group after ovariectomy. SETTING: University animal laboratory. ANIMAL(S): Balb/c female rats. INTERVENTION(S): Vaginas were removed and processed for immunohistochemical analysis. MAIN OUTCOME MEASURE(S): We recorded the localization, distribution, and expression of VDR in vaginal epithelium during the rat estrus cycle and in ovariectomized rats. RESULT(S): In cyclic rats, VDR was detected in basal and suprabasal cells during all of the cycle periods. In apical cells, VDR was positive in diestrus and estrus but negative in proestrous. In ovariectomized rats, VDR was not detected in any layers of vaginal epithelium. CONCLUSION(S): In vaginal epithelium, the presence of VDR was shown by using immunohistochemical techniques. During the estrous cycle, VDR has an important role in the proliferation and differentiation of vaginal squamous epithelium that is similar to the effects of estrogen.  相似文献   
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