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101.
This study compares two cultivation methods (Petri dishes vs. Phytotoxkit containers; tap water vs. Knop’s solution) for standard seedling growth tests. Seeds and young seedlings of Sinapis alba and Hordeum vulgare were used as study subjects and the adverse effect of Cd was assessed. Under testing conditions, only H. vulgare showed a significant decrease in seed germination in Petri dishes when tap water was used as the growth medium (70.8 % ± 46.4 %). No significant differences in IC50 values were found in either plant type for root growth between plants cultivated in Phytotoxkit containers and those cultivated in Petri dishes. The same findings were confirmed for shoot growth in H. vulgare, but not in S. alba. Suitability of Phytotoxkit containers over traditionally used Petri dishes for phytotoxicity determination was confirmed by higher correlation coefficients for all tests.  相似文献   
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BACKGROUND: Although several shortterm animal models of stunning and hibernation have been studied extensively, it has been difficult to produce a consistent animal model of chronic hibernation. The aim of the present study was to develop a nonsurgical porcine stent model of coronary stenosis in order to investigate the relationship between chronic dysfunctional myocardium and viability using 2D-echo, dobutamine stress echo (DSE) and positron emission tomography (PET). METHODS AND RESULTS: Focal progressive coronary stenosis was induced by implantation of an oversized stent in the left anterior descending (LAD) and/or circumflex (LCX) coronary artery in a total of 115 pigs, according to various experimental protocols: copper stent in the LAD (group I, n = 5); noncoated stainless steel stent in the LAD combined with balloon overstretch (group II, n = 7); poly(organo)phosphazene-coated stent in the LAD (group III, n = 77); and poly(organo)phosphazene-coated stent in both the LAD and the LCX (group IV, n = 26). Occurrence of left ventricular dysfunction was evaluated weekly by 2D-echo. At the time of left ventricular dysfunction the presence of viable myocardium within the dysfunctional region was investigated with DSE and PET, and confirmed by histology. The degree of coronary artery stenosis was measured by quantitative coronary angiography and morphometry. Severe coronary artery stenosis in the presence of dysfunctional, but viable, myocardium was induced in groups III and IV (47% and 11% of the animals, respectively). CONCLUSIONS: The authors developed a nonsurgical porcine stent model of progressive coronary stenosis using an oversized polymer-coated stent resulting in chronically decreased myocardial function, with residual inotropic reserve and viable myocardium. This condition may arise from repetitive periods of ischemia, or from sustained hypoperfusion, or a combination of these processes eventually leading to myocardial hibernation. (Int J Cardiovasc Intervent 2000; 3: 111-120)  相似文献   
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Autoimmune pancreatitis is a rare form of pancreatitis characterized by responsiveness to steroid therapy and an often relapsing disease course. The mainstay of therapy is oral corticotherapy. Associations of interstitial nephritis with various autoimmune disorders have been described. We hereby report the case of a 69-year-old Caucasian man with a 2-year history of autoimmune pancreatitis, who presented with impairment of kidney function, proteinuria, and hypertension. Renal histopathology showed severe diffuse interstitial nephritis. With oral prednisone and ACE inhibitor therapy, complete recovery of kidney function was not achieved and proteinuria persisted. Therefore, mycophenolate mofetil was initiated. After 8 weeks, serum creatinine decreased, and a nearly complete and sustained resolution of proteinuria was seen, while tapering oral steroid doses. With autoreactive T cells playing a major role in the pathogenesis of both diseases, a common etiology of pancreatitis and interstitial nephritis can be assumed, and the beneficial effects of an inhibitor of lymphocyte proliferation, such as mycophenolate mofetil, can be explained. We infer from our case that mycophenolate mofetil can be effective in the control of simultaneous autoimmune pancreatitis and interstitial nephritis.  相似文献   
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As part of the Mother-Infant Health Study, we describe infant feeding practices among HIV-infected and HIV-uninfected mothers over a 12-month period when the Western Cape Province prevention of mother-to-child transmission (PMTCT) program was transitioning from a policy of exclusive formula feeding to one of exclusive breastfeeding. Two hundred pairs of mother and HIV-uninfected infant were included in the analysis, among whom 81 women were HIV uninfected and breastfeeding. Of the 119 HIV-infected mothers, 50 (42%) were breastfeeding and 69 (58%) were formula feeding. HIV-infected mothers predominantly breastfed for 8.14 (7.71–15.86) weeks; HIV-uninfected mothers predominantly breastfed for 8.29 (8.0–16.0) weeks; and HIV-infected mothers predominantly formula fed for 50.29 (36.43–51.43) weeks. A woman’s HIV status had no influence on the time to stopping predominant breastfeeding (P?=?0.20). Our findings suggest suboptimal duration of breastfeeding among both HIV-infected and HIV-uninfected mothers. Providing support for all mothers postdelivery, regardless of their HIV status, may improve breastfeeding practices.  相似文献   
110.

Purpose

To compare recurrence frequency and location between different types of bowel resections in Crohn’s disease patients.

Methods

This was a retrospective study of consecutive patients undergoing bowel resection for Crohn’s disease between 2006 and 2016. Type of primary operation was recorded and grouped as ileocolic resection, small bowel resection, segmental colon resection with colocolic anastomosis or colorectal anastomosis, colectomy with ileorectal anastomosis, or end stoma operation. Binary logistic regression was used to compare surgical recurrence frequency between groups. We also investigated how Crohn’s disease location at reoperations was related to the primary bowel resection type.

Results

Altogether, 218 patients with a median follow-up of 4.7 years were included in our study. Reoperation was performed in 42 (19.3%) patients. The risk of reoperation using the ileocolic resection group as reference was the following: small bowel resection (odds ratio (OR) 2.95, 95% confidence interval (CI) 1.01–8.66; P?=?0.049), segmental colon resection with colocolic or colorectal anastomosis (OR 6.20, 95% CI 2.04–18.87; P?=?0.001), colectomy with ileorectal anastomosis (OR 26.57, 95% CI 2.59–273.01; P?=?0.006), and end stoma operation (OR 4.62, 95% CI 1.90–11.26; P?=?0.001). In case of surgical recurrence, the reoperation type and location correlated with the primary bowel resection type.

Conclusions

Reoperation frequency in Crohn’s disease is lower after ileocolic resection than after other types of bowel resections. Surgical recurrence in Crohn’s disease tends to maintain the disease location of the primary operation. One third of Crohn’s patients undergoing an end stoma operation will still need new bowel resections due to recurrence.
  相似文献   
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