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61.
I Martin-Kleiner Z Flegar-Mestric R Zadro D Breljak S Stanovic Janda R Stojkovic M Marusic M Radacic M Boranic 《Food and chemical toxicology》2001,39(7):717-727
Zeolites are natural or synthetic crystalline alumosilicates with ion exchanging properties. Supplied in fodder, they promote biomass production and animal health. Our aim was to assess the effects of the natural zeolite, clinoptilolite, on hematopoiesis, serum electrolytes and essential biochemical indicators of kidney and liver function in mice. Two preparations differing in particle size were tested: a powderized form obtained by countercurrent mechanical treatment of the clinoptilolite (MTCp) and normally ground clinoptilolite (NGCp). Young adult mice were supplied with food containing 12.5, 25 or 50% clinoptilolite powder. Control animals received the same food ration without the clinoptilolite. After 10, 20, 30 and 40 days, six animals from each group were exsanguinated to obtain blood for hematological and serum for biochemical measurements as well as to collect femoral bone marrow for determination of hematopoietic activity. Clinoptilolite ingestion was well tolerated, as judged by comparable body masses of treated and control animals. A 20% increase of the potassium level was detected in mice receiving the zeolite-rich diet, without other changes in serum chemistry. Erythrocyte, hemoglobin and platelet levels in peripheral blood were not materially affected. NGCp caused leukocytosis, with concomitant decline of the GM-CFU content in the bone marrow, which was attributed to intestinal irritation by rough zeolite particles. The mechanically treated clinoptilolite preparation caused similar, albeit less pronounced, changes. In a limited experiment, mice having transplanted mammary carcinoma in the terminal stage showed increased potassium and decreased sodium and chloride levels, severe anemia and leukocytosis, decreased bone marrow cellularity and diminished content of hematopoietic progenitor cells in the marrow. The clinoptilolite preparations ameliorated the sodium and chloride decline, whereas the effects on hematopoiesis were erratic. 相似文献
62.
Zoran Dudvarski Ivica Pendjer Vojko Djukic Ljiljana Janosevic Anton Mikic 《European archives of oto-rhino-laryngology》2008,265(8):923-927
The objective of our study was to analyze the intensity of subjective symptoms and objective findings of endoscopy and CT scanning in chronic rhinosinusitis, in the groups with and without nasal polyps. To evaluate the intensity of subjective symptoms visual analogue scale (VAS) was used, while scores were obtained by adding grades. Endoscopic finding was given in scores recommended by Lanza and Kennedy and CT results were presented by Lund-Mackay scoring system. The study included 90 consecutive adult patients, 47 males (52%) and 43 females (48%), mean age 45 years. The group with chronic rhinosinusitis without nasal polyps (uncomplicated form) consisted of 30 patients, while the group with polyps (complicated form) included 60 patients. Comparing mean intensity values of all subjective symptoms between these two groups we found out that nasal obstruction, nasal secretion and hyposmia were significantly more manifested in the polyp group (P < 0.01). Facial congestion was also more manifested in the polyp group (P < 0.05). Mean score value of major symptoms was 35.55 in the polyp group, and 23.13 in the group without polyps (P < 0.01). Mean value of total symptom scores was 48.68 in the polyp group, and 35.00 in the group without polyps (P < 0.01). Endoscopic score was approximately 9.03 in the polyp group, and 2.43 in the group without polyps (P < 0.01). CT score was 16.05 on an average in the polyp group, and 4.37 in the group without polyps (P < 0.01). Chronic rhinosinusitis complicated by nasal polyposis is characterized by higher degree of nasal obstruction, nasal secretion, hyposmia and facial congestion, which results in higher score of major and total score of symptoms, respectively. This form is also characterized by worse objective findings, which is reflected in higher endoscopic and CT scores. 相似文献
63.
Asim Kurjak Gordon Crvenkovic Aida Salihagic Ivica Zalud Mladen Miljan 《Journal of clinical ultrasound : JCU》1993,21(1):3-8
Transvaginal color Doppler was performed in 198 volunteer pregnant women whose menstrual age ranged from the fifth to the twelfth week. In all patients an attempt was made to obtain signals from both uterine arteries, peritrophoblastic/retroplacental vessels, umbilical arteries, fetal aorta, intracranial vessels, and corpus luteum flow. With the combination of color and pulsed Doppler transvaginal sonography, detection of vascular structures was greatly facilitated and the amount of time for examination significantly reduced. Flow velocity waveforms were measured and results were analyzed by calculation of the Resistance Index. During the early stage of pregnancy, we were able to locate both uterine arteries in all cases and continuous diastolic shift signal was found. Flow in the peritrophoblastic/retroplacental area was observed with an overall success rate of 94%. Blood flow in the umbilical artery and fetal aorta was visualized by color Doppler starting from the seventh week. Intracranial blood flow could be visualized starting from the tenth week in some cases. Diastolic flow in these vessels was detectable starting from the twelfth week. Corpus luteum flow was found in 148 cases (75%) and the Resistance Index decreased as pregnancy progressed © 1993 by John Wiley & Sons, Inc. 相似文献
64.
A randomized,double-blind trial of the effect of metronidazole on pain after closed hemorrhoidectomy
Balfour L Stojkovic SG Botterill ID Burke DA Finan PJ Sagar PM 《Diseases of the colon and rectum》2002,45(9):1186-1190
PURPOSE: Patients consider hemorrhoidectomy to be a painful operation. Attempts to reduce the length of inpatient stay have concentrated mainly on a reduction in postoperative pain. Metronidazole has been shown to reduce pain after open hemorrhoidectomy. The aim of this study was to evaluate the effect of metronidazole after closed hemorrhoidectomy.
METHODS: Thirty-eight patients undergoing closed hemorrhoidectomy were randomly allocated to receive metronidazole 400 mg (n = 18) or placebo (n = 20) three times daily for seven postoperative days. All patients received a stool softener and analgesics perioperatively. Linear analog scales were used to assess expected pain, actual pain and patient satisfaction. Time to first bowel movement, return to normal activity, complications, and use of additional analgesics were recorded.
RESULTS: Both groups of patients experienced less pain than expected. Patients in the metronidazole group required fewer additional analgesics postoperatively (6.3 vs. 26.3 percent), and satisfaction scores in the placebo group were higher at one week (0.5 vs. 2.5), although these differences were not statistically significant. There were no differences in pain actually experienced, time to first bowel movement, return to normal activity, or complications between the two groups. Satisfaction scores at six weeks for all patients were relatively high, with no significant difference between the groups.
CONCLUSION: Closed hemorrhoidectomy results in high patient satisfaction and low pain scores. The use of postoperative metronidazole did not reduce postoperative pain. 相似文献
65.
J. Mueller M. Stojkovic A. K. Berger K. D. Rosenberger C. L. Schlett H.-U. Kauczor T. Junghanss T. F. Weber 《Abdominal imaging》2016,41(2):221-230
Purpose
Hepatic alveolar echinococcosis (AE) resembles intrahepatic cholangiocarcinoma (ICC) on radiological imaging. The purpose of this study was to identify criteria to discriminate AE from ICC with CT and MR Imaging.Methods
One hundred and sixteen imaging studies of 94 patients (CT n = 65; MRI n = 51) diagnosed with AE (n = 55) or ICC (n = 39) were retrospectively reviewed by two blinded radiologists for lesion features including enhancement pattern and matrix composition. A consensus read was conducted in cases of disagreement. Uni- and multivariate logistic regression with bootstrapping were used for analysis.Results
Using CT, no or septal enhancement and calcification yielded the highest values of sensitivity/specificity (90.9%/90.6% and 81.8%/96.9%) for AE. Using MRI, no or septal enhancement and cystic components achieved the highest sensitivity/specificity (90.9%/100.0% and 84.8%/66.7%) for AE. Multivariate logistic regression identified the following strong independent predictors for AE: for MRI, no or septal enhancement (odds ratio [OR] 322.4; p < 0.001); for CT, no or septal enhancement and calcification (OR 35.9 and 42.5; p < 0.001 and p < 0.01, respectively). No or septal enhancement and calcification demonstrated the highest interreader agreement (>90%).Conclusion
Enhancement characteristics and matrix calcifications offer the strongest discriminating potential between AE and ICC with a high sensitivity, specificity, and interreader agreement.66.
Nataša Jovanov‐Milošević Zdravko Petanjek Davor Petrović Miloš Judaš Ivica Kostović 《The European journal of neuroscience》2010,32(9):1423-1432
The aim of this study was to investigate the morphology, molecular phenotypes, distribution and developmental history of interstitial neurons in the human corpus callosum, here defined as intracallosal neurons. We analysed 26 fetuses, three newborns, five infants and children, and eight adults [age range – 15 weeks postconception (PCW) to 59 years] by means of acetylcholinesterase (AChE) histochemistry and immunohistochemistry for neuron markers (MAP2, NeuN, NPY, calretinin and calbindin). We found a heterogeneous neuron population, positioned within the callosal trunk itself (aside from neurons present in the transient midline structures such as callosal sling, septa or subcallosal zone), which was most numerous during the second half of gestation and early postnatal years. We named these cells intracallosal neurons. At 15 PCW, the intracallosal neuron population consisted of poorly differentiated, small fusiform or bipolar, migratory‐like MAP2‐ or calretinin‐positive neurons which could be observed until mid‐gestation. Later the population comprised morphologically diverse, predominantly well‐differentiated MAP2‐, NPY‐, calbindin‐ and AChE‐positive neurons. The morphological differentiation of intracallosal neurons culminated in the newborns and remained pronounced in infants and children. In the adult brain, the intracallosal neurons were found only sporadically, with small somata and poorly stained dendrites. Thus, intracallosal neurons form part of a transitory neuron population with a developmental peak contemporaneous to the critical period of callosal formation. Therefore, they may be involved in processes such as axon guiding or elongation, withdrawal of exuberant axons, fasciculation, or functional tuning, which occur at that time. 相似文献
67.
Silvana Jukić Krmek Ivana Bogdan Paris Simeon Goranka Prpić Mehičić Davor Katanec Ivica Anić 《Lasers in medical science》2010,25(6):823-828
The aim of this study was to evaluate microleakage along resin restoration in cavities prepared with an erbium:yttrium–aluminium–garnet
(Er:YAG) laser, with and without acid etching, and to compare it with that in diamond-drilled cavities. Thirty intact molars
were divided into three equal groups. In the teeth in group I, class V cavities were prepared with a diamond drill. Cavities
in groups II and III were prepared with an Er:YAG laser (400 mJ/15 Hz for enamel and 250 mJ/10 Hz for dentine). The cavities
in groups I and II were acid-etched and adhesive and flowable composite were applied to all cavities. The specimens were first
immersed in dye for 24 h and then in 5% nitric acid for 72 h for softening. The fillings were extracted and photographed through
a dissecting microscope. The leakage area was measured with specially designed software. The Kruskal–Wallis test showed that
the best ranking was group II [mean range (m.r.) = 27.46], followed by group I (m.r. = 33.48) and, lastly, group III (m.r. = 45.15).
The differences between groups I and III (P = 0.023) and between groups II and III were statistically significant (P = 0.080). The least microleakage was found in those cavities prepared by Er:YAG laser and subsequently acid-etched, whereas
the most leakage was in the lased cavities that had not been etched; the traditional diamond-drilled acid-etched cavities
produced medium leakage. 相似文献
68.
Sinisa Stojkovic MD PhD Miodrag Ostojic MD PhD Milan Nedeljkovic MD PhD Goran Stankovic MD PhD Branko Beleslin MD PhD Vladan Vukcevic MD Dejan Orlic MD Aleksandra Arandjelovic MD PhD Jelena Kostic MD Miodrag Dikic MD Miloje Tomasevic MD PhD 《Catheterization and cardiovascular interventions》2010,75(3):317-325
Objectives : The aim of this study was to assess the role of short oral administration of rapamycin, without loading dose, in the reduction of restenosis rate after bare metal stent implantation. Background : Previous studies suggest that the administration of oral rapamycin reduces angiographic restenosis after bare metal stent implantation. Methods : This was prospective, open‐label study of 80 patients randomized to either oral rapamycin (2 mg/day for 30 days, starting within 24 hr of stent implantation) or no therapy after implantation of a coronary bare metal stent. The primary study end point was incidence of angiographic binary restenosis and late loss at six months. The secondary end points were target lesion revascularization (TLR), target vessel revascularization (TVR), and incidence of major adverse cardiovascular events (MACE) at 6 months. Results : Angiographic follow up was completed in 72/80 (90%) of patients. In the rapamycin group, the drug was well tolerated (22.5% minor side effects) and was maintained in 100% of patients. At six months, the in‐segment binary restenosis was 10.5% in rapamycin group vs. 51.4% in no‐therapy group, P < 0.001) and the in‐stent binary restenosis was 7.9% in rapamycin group vs. 48.7% in no‐therapy group, P < 0.001. The in‐segment late loss was also significantly reduced with oral therapy (0.29 ± 0.39 vs. 0.86 ± 0.64 mm, respectively, P < 0.001). Similarly, after six months, patients in the oral rapamycin group also showed a significantly lower incidence of TLR and TVR (7% vs. 22.7%, respectively, P = 0.039) and MACE (7% vs. 22.7%, respectively, P = 0.039). Conclusions : This study showed that the administration of oral rapamycin (2 mg/day, without loading dose) during 30 days after stent implantation significantly reduces angiographic and clinical parameters of restenosis. © 2009 Wiley‐Liss, Inc. 相似文献
69.
The purpose of this study was to evaluate vibrations induced by an erbium:yttrium–aluminum–garnet (Er:YAG) laser in the non-contact
mode and compare the vibrations with different pulse durations and energy parameters. The experiment was conducted on an extracted
tooth built up in silicone impression material. The vibrations were measured by piezoelectric accelerometer for a super-short
pulse (SSP), a very short pulse (VSP), and a short pulse (SP) at a frequency of 5 Hz for 1 s. For VSP and SP, the energy parameters
tested were 200 mJ, 300 mJ, and 400 mJ. Measurements were performed 15 times for each individual irradiation energy level.
The highest values of vibrations were measured for SP (0.160 ± 0.04 m/s2), and the lowest were measured for VSP mode at the energy parameter 200 mJ (0.05 ± 0.02 m/s2). There was a statistically significant (P < 0.01) difference between the various laser pulse modes (SSP, VSP, SP) at different energy parameters. At energy levels
of 300 mJ and 400 mJ, the least amount of vibration during cavity preparations with the non-contact Er:YAG laser was produced
by SSP mode. 相似文献
70.
Krebs S Medugorac I Röther S Strässer K Förster M 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(16):6746-6751
The bovine form of the autosomal recessive neurodegenerative disease spinal muscular atrophy (SMA) shows striking similarity to the human form of the disease. It has, however, been mapped to a genomic region not harboring the bovine orthologue of the SMN gene, mutation of which causes human SMA. After refinement of the mapping results we analyzed positional and functional candidate genes. One of three candidate genes, FVT1, encoding 3-ketodihydrosphingosine reductase, which catalyzes a crucial step in the glycosphingolipid metabolism, showed a G-to-A missense mutation that changes Ala-175 to Thr. The identified mutation is limited to SMA-affected animals and carriers and always appears in context of the founder haplotype. The Ala variant found in healthy animals showed the expected 3-ketodihydrosphingosine reductase activity in an in vitro enzyme assay. Importantly, the Thr variant found in SMA animals showed no detectable activity. Surprisingly, in an in vivo assay the mutated gene complements the growth defect of a homologous yeast knockout strain as well as the healthy variant. This finding explains the viability of affected newborn calves and the later neuron-specific onset of the disease, which might be due to the high sensitivity of these neurons to changes in housekeeping functions. Taken together, the described mutation in FVT1 is a strong candidate for causality of SMA in cattle. This result provides an animal model for understanding the underlying mechanisms of the development of SMA and will allow efficient selection against the disease in cattle. 相似文献