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51.
Popović Suić S Cerovski B Tojagić M 《Acta medica Croatica : c?asopis Hravatske akademije medicinskih znanosti》2004,58(5):407-409
The upper lid position is abnormal if it exposes a white band of sclera between the lid margin and the upper corneal limbus while the retracted lower lid lies below the inferior corneal margin and is tethered to the orbital margin. Lid retraction is a sign of many congenital and acquired diseases and is characterised by multifactorial etiology. The aim of this study was to discuss the etiology of lid retraction divided into four categories: neurogenic, myogenic, mechanical and miscellaneous, what suggests a successful differential diagnostic and therapeutic approach. 相似文献
52.
Basić-Jukić N Kes P Basić-Kes V Brunetta B 《Acta medica Croatica : c?asopis Hravatske akademije medicinskih znanosti》2004,58(1):63-66
Paraneoplastic neurologic syndromes are disorders of the nervous system function caused by cancer but not due to metastatic disease, vascular or metabolic deficits, infections, nutritive deficiency, nor side effects of antineoplastic drugs or irradiation. Immunologic factors probably play the crucial role in the pathogenesis of paraneoplastic neurologic syndromes, but nonimmunologic mechanisms that include metabolic abnormalities and competition for substrate are also involved. Paraneoplastic cerebellar degeneration most commonly occurs in the setting of gynecologic cancers, but it accompanies the small-cell lung cancer too. Other tumors are infrequently associated with cerebellar degeneration. Several paraneoplastic antibodies have been identified in patients with paraneoplastic cerebellar degeneration. Their association with particular cancers may help identify an occult lesion. Anti-Yo antibodies are directed against Purkinje cell antigens and occur in patients with cerebellar degeneration who have breast cancer or gynecologic tumors. A target antigen of anti-Yo antibody is CDR2 protein that is normally expressed only in the brain and testis. Patients with paraneoplastic cerebellar degeneration present with dizziness, nausea and vomiting followed by gait instability, diplopia, gait and appendicular ataxia, dysarthria and dysphagia. Therapeutic options include tumor excision, chemotherapy and/or irradiation, and adjuvant therapy with glucocorticoids, immunoglobulins and plasmapheresis. The role of plasmapheresis in the treatment of paraneoplastic cerebellar degeneration is still uncertain. Reports of its efficacy are anecdotal. We present patient with paraneoplastic cerebellar degeneration with positive anti-Yo antibodies and tumor of the ovaries whose neurologic status significantly improved after four daily plasmaphereses, which was accompanied by a fourfold decrease in the anti-Yo antibodies titer. Further investigations are needed to define a protocol for plasmapheresis in the treatment of patients with paraneoplastic syndromes. 相似文献
53.
Adenoviral vectors expressing siRNAs for discovery and validation of gene function 总被引:5,自引:0,他引:5 下载免费PDF全文
Arts GJ Langemeijer E Tissingh R Ma L Pavliska H Dokic K Dooijes R Mesić E Clasen R Michiels F van der Schueren J Lambrecht M Herman S Brys R Thys K Hoffmann M Tomme P van Es H 《Genome research》2003,13(10):2325-2332
RNA interference is a powerful tool for studying gene function and for drug target discovery in diverse organisms and cell types. In mammalian systems, small interfering RNAs (siRNAs), or DNA plasmids expressing these siRNAs, have been used to down-modulate gene expression. However, inefficient transfection protocols, in particular, for primary cell types, have hampered the use of these tools in disease-relevant cellular assays. To be able to use this technology for genome-wide function screening, a more robust transduction protocol, resulting in a longer duration of the knock-down effect, is required. Here, we describe the validation of adenoviral vectors that express hairpin RNAs that are further processed to siRNAs. Infection of cell lines, or primary human cells, with these viruses leads to an efficient, sequence-specific, and prolonged reduction of the corresponding target mRNA, resulting in a reduction of the encoded protein level in the cell. For knock-down of one of the targets, GalphaS, we have measured inhibition of ligand-dependent, G-protein-coupled signaling. It is expected that this technology will prove to be of great value in target validation and target discovery efforts. 相似文献
54.
Grgić O Matijević R 《Acta medica Croatica : c?asopis Hravatske akademije medicinskih znanosti》2005,59(2):129-135
Neonatal respiratory distress syndrome (RDS) is one of the biggest problems in modern obstetrics. The incidence of RDS is 1%-2%. RDS is a condition of insufficient surfactant production. Surfactant is a complex molecule which is responsible for maturation of fetal lungs. The most important factor for insufficient surfactant production and pulmonary immaturity is shortening of gestation, i.e. preterm delivery. Antenatal corticosteroids for maturation of fetal lungs are in use for over thirty years. Corticosteroids decrease the incidence and intensity of RDS, the severity of intracerebral hemorrhage, and overall neonatal morbidity and mortality. The mechanism of corticosteroid action is probably induction of fetal pulmonary enzyme complex that is responsible for adequate surfactant production and regulation of pulmonary interstitial fluids. In this literature review, we analyze long- and short-term benefits and risks of single and multiple antenatal corticosteroid administration. 相似文献
55.
nm23-H1 expression and loss of heterozygosity in colon adenocarcinoma 总被引:18,自引:0,他引:18
Kapitanović S Cacev T Berković M Popović-Hadzija M Radosević S Seiwerth S Spaventi S Pavelić K Spaventi R 《Journal of clinical pathology》2004,57(12):1312-1318
BACKGROUND: The discovery that genetic alterations in oncogenes and tumour suppressor genes accompany tumour formation in many human tumours has encouraged the search for genes that promote or suppress tumour spread and metastasis; nm23 is a promising candidate for a metastasis suppressing gene.AIMS: To evaluate whether expression of nm23-H1 protein or loss of heterozygosity (LOH) of the nm23-H1 gene is associated with colon cancer progression. MATERIALS/METHODS: Paraffin wax embedded tissue sections were analysed immunohistochemically. DNA isolated from normal and tumour tissue was used for LOH analysis using a variable nucleotide tandem repeat (VNTR) marker located in the untranslated 5' region of the nm23-H1 gene. RNA isolated from tumour and normal tissue was used for "real time" RT-PCR. RESULTS: Of 102 adenocarcinomas examined, 58.8% stained weakly for nm23-H1 protein. There was a negative correlation between nm23-H1 positivity and tumour histological grade. In VNTR analysis, 70.2% of patients were informative and 27.4% of tumours had nm23-H1 LOH. There was a positive correlation between nm23-H1 LOH and both tumour histological grade and Dukes's stage. Expression of nm23-H1 mRNA was increased in 22 of 30 colon tumours compared with normal tissue. No significant correlation was found between nm23-H1 mRNA expression and histological grade or Dukes's stage of tumours. CONCLUSIONS: These findings suggest that nm23-H1 protein expression in early stages may have a role in suppressing metastasis in sporadic colon cancer, whereas at a later stage both reduced nm23-H1 protein expression and LOH of the nm23-H1 gene may play role in colon cancer progression and metastasis. 相似文献
56.
Ivancic J Gulija TK Forcic D Baricevic M Jug R Mesko-Prejac M Mazuran R 《Virus research》2005,109(1):95-105
Eleven mumps vaccine strains, all containing live attenuated virus, have been used throughout the world. Although L-Zagreb mumps vaccine has been licensed since 1972, only its partial nucleotide sequence was previously determined (accession numbers , and ). Therefore, we sequenced the entire genome of L-Zagreb vaccine strain (Institute of Immunology Inc., Zagreb, Croatia). In order to investigate the genetic stability of the vaccine, sequences of both L-Zagreb master seed and currently produced vaccine batch were determined and no difference between them was observed. A phylogenetic analysis based on SH gene sequence has shown that L-Zagreb strain does not belong to any of established mumps genotypes and that it is most similar to old, laboratory preserved European strains (1950s-1970s). L-Zagreb nucleotide and deduced protein sequences were compared with other mumps virus sequences obtained from the GenBank. Emphasis was put on functionally important protein regions and known antigenic epitopes. The extensive comparisons of nucleotide and deduced protein sequences between L-Zagreb vaccine strain and other previously determined mumps virus sequences have shown that while the functional regions of HN, V, and L proteins are well conserved among various mumps strains, there can be a substantial amino acid difference in antigenic epitopes of all proteins and in functional regions of F protein. No molecular pattern was identified that can be used as a distinction marker between virulent and attenuated strains. 相似文献
57.
Kosmaczewska A Ciszak L Boćko D Frydecka I 《Archivum immunologiae et therapiae experimentalis》2001,49(1):39-46
The generation of an effective immune response involves antigen-specific T cell expansion and differentiation of effector function. T cell activation requires at least two distinct signals, including signaling via the antigen-specific T cell receptor (TCR) and a costimulatory pathway. Antigen stimulation of T cells can lead either to a productive immune response, characterized by proliferation, differentiation, clonal expansion and effector function, or, in the absence of an appropriate costimulation, to a state of long-lasting unresponsiveness, termed anergy. Anergic T cells fail to proliferate and secrete cytokines in response to secondary stimulation. The interaction between the costimulatory molecule CD28 on T cells and members of the B7 family on antigen-presenting cell results in upregulation of T cell proliferation and cytokine production and induces the expression of the anti-apoptotic protein Bcl-xl. Based of these findings, the two-signal requirement model for T cell activation is generally accepted today. The negative regulatory mechanisms during T cell activation are not well understood, but they are crucial for the maintainance of lymphocyte homeostasis. For several years the functional role of the enigmatic CD28 homologue cytotoxic T lymphocyte antigen-4 (CTLA-4) in T cell activation has been both obscure and controversial. CTLA-4 was initially supposed to provide a costimulatory signal in conjunction with TCR/CD3 signaling. Today we know that CD28 and CTLA-4 molecules may have diametrically opposed functions: signaling via CD28, in conjunctive with TCR, is required for T cell activation, while signaling via CTLA-4 is a negative signal that inhibits T cell proliferation. How the T cell integrates signals through the TCR/CD3 complex, CD28 and CTLA-4 to initiate, maintain and terminate antigen-specific immune response is in fact not fully clarified. In this review, we will focus on the emerging role of CTLA-4 as a negative regulator of T lymphocyte activation and its role in the dynamic interplay of activatory and inhibitory signals. 相似文献
58.
Whole cell patch-clamp recording and intracellular staining with biocytin allowed the morphological and electrophysiological characterization of "giant" cells, studied in stratum (st.) radiatum of the CA3 region in 17- to 21-day-old rat hippocampal slices. These neurons had extensive dendritic arborization, a triangular soma, and a bipolar vertical orientation with axons directed to the pyramidal layer or extended into the st. oriens. Giant cells had significantly higher input resistance and shorter action potentials compared with CA3 pyramidal cells. Evoked action potentials were typically followed by an afterdepolarizing potential (ADP). During depolarizing current injection, most (80%) of recorded giant cells displayed a regular firing pattern (maximum steady-state firing rate, approximately 30 Hz) characterized by a modest early accommodation, whereas irregular firing was observed in the remaining 20% of giant cells. Hyperpolarizing current pulses induced a slow inward rectification of the electrotonic voltage responses, blocked by 2 mM external Cs(+). N-methyl-D-aspartate (NMDA) and non-NMDA-mediated excitatory postsynaptic currents (EPSCs) measured under voltage clamp were distinguished on the basis of their voltage dependence and sensitivity to specific NMDA and non-NMDA glutamate receptor blockers. Non-NMDA EPSCs possessed a linear current-voltage relationship. EPSCs elicited by st. lucidum stimulation were reversibly reduced (mean, 23%) by the group II metabotropic glutamate receptor agonist (2S, 1'R, 2'R, 3'R)-2-(2,3-dicarboxyl-cyclopropyl)-glycine (DCG-IV, 1 microM). GABA(A)-mediated postsynaptic currents were subject to paired-pulse depression that was inhibited by the GABA(B) antagonist CGP 55845A (5 microM). We conclude that CA3 giant cells represent a particular class of hippocampal neuron located in st. radiatum that shares only some morphological and physiological properties with principal cells. 相似文献
59.
Bogdan Karakašević 《Medical microbiology and immunology》1955,142(1):27-37
Ohne Zusammenfassung 相似文献
60.
Countertransference in therapists working with patients with posttraumatic stress disorder (PTSD) differs from countertransference in other psychotherapeutical settings. In this article we discuss the specificities of counter- transference in treating PTSD patients and its relation to empathy. The most difficult countertransference problems occur in treating multiply traumatized patients. Countertransference may occur towards an event (e.g., war), patients who have killed people, as well as to colleagues who avoid treating PTSD patients, or towards a supervisor who avoids, either directly or indirectly, supervision of therapists working with PTSD patients. Our recommendation for the prevention of problems in treating PTSD patients include : 1) careful selection of the therapist or helper, both in the personality structure and training; 2) prevention by debriefing and team work and peer supervision; and 3) education - theoretical, practical, and therapeutical. 相似文献