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Contrast-induced nephropathy is a common cause of acute renal failure, and the mechanisms underlying this injury are not completely understood. We sought to determine how physicochemical properties of contrast media may contribute to kidney damage in rats. We administered contrast media of equivalent iodine concentrations but differing physiocochemical properties: the high-osmolality iopromide was compared to the high-viscosity iodixanol. In addition, the non-iodinated substances mannitol (equivalent osmolality to iopromide) and dextran (equivalent viscosity to iodixanol) were also studied. Both types of contrast media transiently increased renal and hindquarter blood flow. The high-osmolality agents iopromide and mannitol markedly increased urine production whereas iodixanol, which caused less diuresis, significantly enhanced urine viscosity. Only the high-viscosity agents iodixanol and dextran decreased renal medullary blood flux, erythrocyte concentration, and pO2. Moreover, iodixanol prolonged the tubuloglomerular feedback response and increased plasma creatinine levels to a greater extent than iopromide or dextran. Therefore, the viscosity of contrast media may play a significant role in contrast-induced nephropathy.  相似文献   
43.
The ceruminous glands in the skin of the human external auditory canal are modified apocrine glands, which, together with sebaceous glands, produce the cerumen, the ear wax. Cerumen plays an important role in the protection of the ear canal against physical damage and microbial invasion. We studied the morphology of the glandular cells by light and electronmicroscopy. Antimicrobial and cytoskeletal components of the ceruminous glands were investigated by immunohistochemical methods. Numerous antimicrobial proteins and peptides are present in the ceruminous glandular cells: beta-defensin-1, beta-defensin-2, cathelicidin, lysozyme, lactoferrin, MUC1, secretory component of IgA. These data indicate a crucial role in the innate host defense against diverse pathogens. The apocrine secretion mechanism is a special mode of secretion by which the apical part of the cell cytoplasm surrounded by a membrane is pinched off. We could show that the presence of actin filaments, CK 19 and CK 7, seems to play a role in the pinching-off mechanism. Finally, we showed the secretion of lipid vesicles from the ceruminous gland. We could extend the number of detected antimicrobial peptides and proteins in human ceruminous glandular cells that protect the surface of the external auditory meatus. In addition, we detected proteins involved in the apocrine secretion mode of the ceruminous gland.  相似文献   
44.
The author introduces both the concept and practice of Integrative Parent-Infant Psychotherapy (IPI-P), a treatment specifically designed for the most frequent developmental problems and psychological needs of infants and their parents. Based on growing knowledge from interdisciplinary infancy research, both basic and clinical, IPI-P has been developed and practised in the "Munich Interdisciplinary Research and Intervention Program" for early regulatory and relationship disorders since the early nineties. Preverbal parent-infant communication represents both the port of entry into the system and the main focus of diagnostics, developmental counselling, interaction guidance, or psychodynamic psychotherapy of distorted communication and distressed/disordered relationships. The method of videomicroanalysis during video-feedback with the parent has proven particularly efficient--while observing, reliving and working through brief episodes of recorded parent-infant interaction. The author illustrates the diagnostic and therapeutic procedures with excerpts from psychotherapy of a toddler with an age-specific regulatory disorder in the context of severely distressed primary relationships.  相似文献   
45.
OBJECTIVE: To investigate actual counseling models for gynecological patients in Switzerland and in Germany. METHODS: A questionnaire investigating psychosomatic care was sent to all Swiss (N=183) and German (N=1078) departments of gynecology, obstetrics, and/or endocrinology. RESULTS: One hundred twenty-eight (27%) completed questionnaires from Germany and 57 (31%) from Switzerland were available for statistical evaluation. Eighty-seven percent of the answering clinics from Switzerland and 93% of those from Germany (ns) considered psychosomatic counseling for gynecological and obstetrical patients as very important or important. Seventy-two percent of the Swiss and 70% of the German departments (ns) offered psychosomatic support. Models of counseling varied greatly between types of hospitals and both countries. Less than 15% of the medical doctors had a formation for psychosomatic counseling. CONCLUSION: Actual possibilities seem to be below the need for psychosomatic care. An adequate formation of medical doctors and considering the effects of psychosomatic care in the discussion on cost reduction for medical treatment would help to improve counseling structures.  相似文献   
46.
To date, six genes are known to cause nemaline (rod) myopathy (NM), a rare congenital neuromuscular disorder. In an attempt to find a seventh gene, we performed linkage and subsequent sequence analyses in 12 Turkish families with recessive NM. We found homozygosity in two of the families at 1q12-21.2, a region encompassing the gamma-tropomyosin gene (TPM3) encoding slow skeletal muscle alpha-tropomyosin, a known NM gene. Sequencing revealed homozygous deletion of the first nucleotide of the last exon, c.913delA of TPM3 in both families. The mutation removes the last nucleotide before the stop codon, causing a frameshift and readthrough across the termination signal. The encoded alphaTm(slow) protein is predicted to be 73 amino acids longer than normal, and the extension to the protein is hypothesised to be unable to form a coiled coil. The resulting tropomyosin protein may therefore be non-functional. The affected children in both families were homozygous for the mutation, while the healthy parents were mutation carriers. Both of the patients in Family 1 had the severe form of NM, and also an unusual chest deformity. The affected children in Family 2 had the intermediate form of NM. Muscle biopsies showed type 1 (slow) fibres to be markedly smaller than type 2 (fast) fibres. Previously, there had been five reports, only, of NM caused by mutations in TPM3. The mutation reported here is the first deletion to be identified in TPM3, and it is likely to be a founder mutation in the Turkish population.European Journal of Human Genetics (2008) 16, 1055-1061; doi:10.1038/ejhg.2008.60; published online 2 April 2008.  相似文献   
47.

Background

Chronic severe pulmonary regurgitation (PR) causes progressive right ventricular (RV) dysfunction and heart failure. Parameters defining the optimal time point for surgery of chronic PR are lacking. The present study prospectively evaluated the impact of preoperative clinical parameters, cardiorespiratory function, QRS duration and NT-proBNP levels on post operative RV function and volumes assessed by cardiac magnetic resonance imaging (CMR) in patients with chronic severe PR undergoing pulmonary valve replacement.

Methods and results

CMR was performed pre- and 6 months postoperatively in 27 patients (23.6 ± 2.9 years, 15 women) with severe PR. Postoperatively, RV endsystolic (RVESVI) and enddiastolic volume indices (RVEDVI) decreased significantly (RVESVI pre 78.2 ± 20.4 ml/m² BSA vs. RVESVI post 52.2 ± 16.8 ml/m²BSA, p < 0.001; RVEDVI pre 150.7 ± 27.7 ml/m²BSA vs. RVEDVI post 105.7 ± 26.7 ml/m²BSA; p < 0,001). With increasing preoperative QRS-duration, postoperative RVEF decreased significantly (r =−0.57; p < 0.005). Preoperative QRS-duration smaller than the median (156 ms) predicted an improved RVEF compared to QRS-duration ≥ 156 ms (54.9% vs 46.8%, p < 0.05). Multivariate analysis identified preoperative QRS duration as an independent predictor of postoperative RVEF (p < 0.005). NT-proBNP levels correlated with changes in RVEDI (r = 0.58 p < 0,005) and RVESVI (r = 0.63; p < 0,0001). Multivariate analysis identified NT-proBNP levels prior to PVR as an independent predictor of volume changes (p < 0.05).

Conclusion

Valve replacement in severe pulmonary regurgitation causes significant reduction of RV volumes. Both, preoperative NT-proBNP level elevation and QRS prolongation indicate patients with poorer outcome regarding RV function and volumes.  相似文献   
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Apocrine glands of Moll are regular components of primate eyelids. We studied the distribution and localization of these glands in three different primate species, the common marmoset, the rhesus monkey, and the hamadryas baboon. In addition, we tested the primate glands of Moll with antibodies against antimicrobial proteins, cytoskeletal proteins and the androgen receptor. The glands of Moll differ in abundance and distribution in different monkeys. In the common marmoset, a representative of the New World monkeys, Platyrrhini, the apocrine glands are frequently found at the lid margin and in the overlying epidermis of the lid. In the rhesus monkey and the hamadryas baboon, representatives of Old World monkeys, Catarrhini, apocrine glands are rarer and located predominantly at the margin of the lid. The immunohistochemical analysis indicates the presence of a variety of antimicrobial proteins, e.g. lysozyme, beta-defensin-2, adrenomedullin, lactoferrin, and IgA, in these glands. Interestingly, there are basically no androgen receptors in the nuclei of apocrine glands at the lid margin in all three monkey species. In the common marmoset, however, androgen receptors are found in apocrine glands of the overlying epidermis of the lid. We speculate that the glands of Moll are derived from apocrine glands as found in the skin of the entire body in New World monkeys which developed at the lid margins of higher primates and humans into specialized glands secreting agents of host defense in the eye.  相似文献   
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