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211.
The synthesis and antimicrobial activity of a new class of macrolide antibiotics which consist of a macrolide scaffold and a quinolone unit covalently connected by an appropriate linker are described. Optimization of several synthetic steps and structural properties of lead compound 26 are discussed. Promising antibacterial properties of this compound and some of its analogues are reported.  相似文献   
212.
Intravascular lymphoma (IVL) is a rare disease characterized by the proliferation of neoplastic cells in the small blood vessels that frequently goes undiagnosed until the time of autopsy. The neoplastic cells are usually of B-cell origin. The clinical course was examined to determine factors that would facilitate antemortem diagnosis. IVL is observed with clinical, histopathological and immunohystochemical methods. This is a unique case because the thyroid gland is a rare place for IVL. Accent is given on immunohystochemical methods and tissue biopsy in the differential diagnosis of IVL when nervous system and thyroid gland dysfunction occur This report indicates that micro-ecosystem of multinodular goitrous might influence the expression of chemokines and/or adhesion moleculs on endothelial and lymphoma cells, leading to heavy infiltration of thyroid gland. Concurrently, that may guide the physician to tissue biopsy facilitating antemortem diagnosis and institution of appropriate therapy.  相似文献   
213.
The article describes the epidemiological characteristics of Q fever in Croatia, during the period before and after the Homeland War. In the ten years prior to the Homeland War (1983-1992) 1053 cases of Q fever were recorded, 16.2% (171) of which on islands and in coastal areas. In the period after the Homeland War (1995-2008), a total of 654 cases was recorded, 59.9% (392) of which on islands and in coastal areas. In addition to reduced incidence, geographic distribution of the disease also changed. Before the war, the highest morbidity rate was recorded in the Sisak-Moslavina County. After the war, the Split-Dalmatia County recorded the highest morbidity rate because in the post-war period sheep from Bosnia and Herzegovina went to this county for winter grazing. The disease might be relevant to the Croatian Army and other armed forces that stay in Croatia as part of NATO forces.  相似文献   
214.
Mucoepidermoid carcinoma (MEC) accounts for approximately 30% of malignant salivary gland tumors and approximately 30% occur in minor salivary glands. The palate is the most frequent localization for those arising in minor glands. A 33-year-old male patient with MEC of the hard palate was treated as an acute odontogenic infection, which was not cured after tooth endodontic treatments, repeated incisions and antibiotics. On the hard palate ovoid, a hard painless mass, which had not extended over the middle palatal line, was observed. Partial maxillectomy was performed. A review of the literature was performed in order to provide a coherent overview on the differential diagnosis of palatal lesions. To the best of authors' knowledge, this is the first report in English literature describing palatal MEC misdiagnosed and treated as odontogenic infection. Considering the extensive list of MEC's differential diagnoses on the hard palate, acute odontogenic infection can now be added to that list.  相似文献   
215.
The assembly of the photosynthetic apparatus was studied during the first six days of development of Fucus serratus L. embryos. HPLC analysis revealed that oospheres and zygotes contain the same photosynthetic pigments (i.e., chlorophyll a, chlorophyll c, fucoxanthin, violaxanthin, and β-carotene) as fully developed thalli. Total pigment amount increased after fertilization, mainly due to an active synthesis of Chl a and fucoxanthin. Spectral modifications revealing the progressive integration of Chl a and Chl c in the photosynthetic units are described. In particular, a distinct emission at 705 nm, reflecting the accumulation of LHC I, was clearly detected. The emission bands at 705 nm and 725 nm were characterized by 77 K excitation fluorescence measurements. Their spectra differed by the presence of a large band at approximately 550 nm due to fucoxanthin in the excitation spectrum of F705 nm. Room temperature variable fluorescence was first observed 30 h after fertilization indicating a functional Photosystem II electron transfer at this developmental stage. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
216.
Archaeobotanical analysis has been used to reconstruct the nest and diet of a small rodent from the Classical period (first century b.c. to second century a.d.) and most probably from Greece. The nest was found in the hollow interior of a very valuable bronze statue of a young athlete, recovered from the waters of the Northern Adriatic and named the Croatian Apoxyomenos. Apoxyomenos was probably the cargo of a Roman ship on one of highly frequented sea routes in ancient times, along which, among other things, a highly developed trade in artworks was maintained. All plant remains were non-carbonised and mineralised; encrusted with metallic salts, especially of copper, and preserved in excellent condition. The nest itself (wisps of “straw” found in the hollow interior of the left forearm of the statue) was mainly composed of stems and leaves of grasses (Poaceae), but also of laurel (Laurus nobilis) leaves and other plant remains. Along with “straw”, a further 837 individual plant remains were found and analysed and 41 different plant taxa were identified. Plant remains that presumably were part of the rodent’s diet belong to various wild and cultivated plants which indicate various anthropogenic habitats probably situated somewhere on the edge of human settlement. From zoological analysis of bite marks found on fruit stones of cherry and olive, and of the potential rodent fauna in the area the statue was assumed to be in prior to becoming submerged, it was established that the rodent was most probably one of the taxa of the Mus domesticus group.  相似文献   
217.
Intracranial hypertension is a severe therapeutic problem, as there is insufficient knowledge about the physiology of cerebrospinal fluid (CSF) pressure. In this paper a new CSF pressure regulation hypothesis is proposed. According to this hypothesis, the CSF pressure depends on the laws of fluid mechanics and on the anatomical characteristics inside the cranial and spinal space, and not, as is today generally believed, on CSF secretion, circulation and absorption. The volume and pressure changes in the newly developed CSF model, which by its anatomical dimensions and basic biophysical features imitates the craniospinal system in cats, are compared to those obtained on cats with and without the blockade of craniospinal communication in different body positions. During verticalization, a long-lasting occurrence of negative CSF pressure inside the cranium in animals with normal cranio-spinal communication was observed. CSF pressure gradients change depending on the body position, but those gradients do not enable unidirectional CSF circulation from the hypothetical site of secretion to the site of absorption in any of them. Thus, our results indicate the existence of new physiological/pathophysiological correlations between intracranial fluids, which opens up the possibility of new therapeutic approaches to intracranial hypertension.  相似文献   
218.
The aim of this study is to test the possible prognostic significance of p53 and Ki67 expression in inverted papilloma of the lateral nasal wall and adjacent sinuses regarding their malignant potential and recurrence. 49 biopsies of the lateral nasal wall and adjacent sinuses obtained from 41 patients from three hospitals were investigated. Immunohistochemically demonstrated p53 and Ki67 expression was measured and statistically evaluated. p53 immunoreactivity was demonstrated in most of papillomas with carcinomas but only in two benign papillomas, while Ki67 demonstrated stronger immunoreactivity in carcinomas and surrounding epithelium. Immunohistochemical staining of inverted sinonasal papillomas for p53 and Ki67 can give useful information concerning the existence of synchronous carcinoma and, in case of high Ki67, a hint toward possible recurrence.  相似文献   
219.
Small enkephalin-related peptides containing a 1-adamantanamine moiety coupled through an amide linkage at the C-terminus were synthesized. Several of the compounds showed high μ opioid activity and μ receptor selectivity. The new adamantanamine derivatives were also examined for antiviral activity against HIV-1 in a cell culture system. Some of them inhibited syncytia formation even when the antigen assay gave evidence for viral replication.  相似文献   
220.
After demonstration that cysteamine induced duodenal lesions in gastrectomized rats, while a number of antiulcer drugs mitigated these lesions, it was shown that one single intrarectal (i.r.) cysteamine application produced severe colon lesions in acute studies in rats. Thus, the further focus was on the protracted effect of cysteamine challenge (400 mg/kg b.w. i.r.) and therapy influence in chronic experiments in female rats. Regularly, cysteamine colon lesions were markedly mitigated by ranitidine (10), omeprazole (10), atropine (10), methylprednisolone (1), sulphasalazine (50; mg/kg), pentadecapeptide BPC 157 (PL-10, PLD-116; 10 microg or 10 ng/kg). Specifically, after 1 or 3 months following initial challenge (cysteamine 400 mg/kg i.r.) in female rat, the therapy [BPC 157 (PL-10, PLD-116 (10.0 microg or 10.0 ng/kg; i.g., i.p., i.r.), ranitidine, omeprazole, atropine, methylprednisolone, sulphasalazine (i.p.)] reversed the protracted cysteamine colon injury: the 1 week-regimen (once daily application) started after 1 month post-cysteamine, as well as the 2 weeks-regimen (once daily application), which started after 3 months. The effect on recidive lesion was also tested. These cysteamine lesions may reappear after stopping therapy (after stopping therapy for 3 weeks at the end of 2-weeks regimen started in 3 months-cysteamine female rats) in sulphasalazine group, while this reappearance is markedly antagonized in pentadecapeptide BPC 157 (PL-10, PLD-116)-rats (cysteamine-colon lesion still substantially low).  相似文献   
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