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81.
The physiological condition of two invasive crayfish species identified in Croatian rivers (Orconectes limosus and Pacifastacus leniusculus) was compared with that of native crayfish populations (Astacus astacus and A. leptodactylus). Hepatosomatic, gonadosomatic and abdominal muscle indices were examined for all four species and within a specific invadernative pair. The results demonstrate that invasive crayfish had better overall physiological condition when compared to native species, with a higher energy content of the hepatopancreas, abdominal muscle and gonads in invasive than in native species, with the exception of A. leptodactylus females which demonstrated an increased ability to allocate energy to reproduction in comparison with other species. These results also indicate that A. astacus is physiologically more unstable than A. leptodactylus and thus more likely to be outcompeted and replaced by non-indigenous crayfish species.  相似文献   
82.
Coccidioidomycosis, the fungal infection caused by dimorphic Coccidioides sp., is typically diagnosed by histopathologic identification of spherules in affected secretions and tissues or by culture. These tests are reliable but time-intensive, delaying diagnosis and treatment. To evaluate a polymerase chain reaction (PCR) test developed to detect Coccidioides sp. in clinical specimens, we conducted a retrospective chart review of all patients (N = 145) who underwent Coccidioides PCR at our institution between April 27, 2007, and May 6, 2008, abstracting clinical, microbiologic, serologic, radiographic, treatment, and follow-up data. One hundred fifty-eight PCR tests (153 respiratory; 5 cerebrospinal fluid) produced 5 positive and 153 negative findings. Five of nine patients (56%) with confirmed or highly probable pulmonary coccidioidomycosis had a positive PCR on respiratory specimens, and four of nine (44%) had a positive culture. Among two patients with coccidioidal meningitis, none had a positive PCR, whereas Coccidioides sp. in fungal culture grew for one of two. Among six asymptomatic patients with probable coccidioidomycosis, none had a positive culture or PCR. Compared with culture of respiratory specimens, PCR demonstrated a sensitivity, specificity, positive predictive value, and negative predictive value of 75, 99, 60, and 99%, respectively. Coccidioides PCR appears accurate in identifying negative results, and its sensitivity is similar to that of fungal culture.  相似文献   
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The aim of this randomized, prospective, study was to evaluate postoperative hospital mortality and morbidity after mitral valve repair by comparing two surgical techniques for resolving mitral valve insufficiency in elderly patients. In comparison were: mitral valve repair vs. mitral valve replacement in patients older than 70 years. In period from January 1st 2006 until August 30th 2009. Eighty patients with mitral valve disease, isolated or associated with other comorbidities, were scheduled for mitral valve repair or mitral valve replacement in our institution. Patients were randomized in two groups, one scheduled for mitral valve repair and another one for mitral valve replacement using the envelope method with random numbers. Results show no difference in hospital mortality and morbidity postoperatively in both groups. In group undergoing valve replacement we had one significant complication of ventricle rupture in emphatically calcified posterior part of mitral valve annulus. In conclusion we found no distinction in postoperative hospital mortality and morbidity after using one of two surgical techniques.  相似文献   
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Conjunctival melanoma is a relatively rare malignancy. It is presented as pigmented nodule in any area of conjunctiva, amelanotic tumors are pink with smooth appearance. The authors describe an amelanotic melanoma of the conjunctiva in an 82-year-old female patient. Cytological, histopathological and immunohistochemical studies revealed an invasive amelanotic melanoma exhibiting S-100 and MART-1 positivity. The patient undervent surgical and chemotherapy treatment and three years after the initial treatment is in the terminal stage of metastatic disease. Absence of pigmentation delayed early clinical detection and treatment. Awareness of this nonpigmented melanoma is crucial for early recognition and appropriate management.  相似文献   
87.
The stability of the revision endoprosthesis components is more difficult to achieve than in primary endoprosthesis due to large bone defects and/or decreased bone mass quality. That is the reason for more frequent complications for revision than in primary arthroplasty. The aim of this study was to investigate the frequency of complications in 122 patients who were operated with the revision endoprosthesis in the Department of Orthopedics in University Hospital Split in the period of 1998 to 2007 and accepted to participate in this study. There were 3 patients treated on bought hips. The average follow up time was four years (0.6-10.6). There were 32 (26.2%) males and 90 (73.8%) females. The average age was 70.66 +/- 7.63 years. The average time from operation to physical therapy was 3.53 +/- 2.56 days. There were 27 (21.6%) complications. The most common complication was infection in 9 (7.2%) cases. From those cases, 4 (3.2%) had superficial, and 5 (4%) had deep infection. From other complications, there were 5 (4%) endoprosthesis reluxations, 2 (1.6%) periprosthetic femur fractures, 5 (4%) urinary infections, and 6 (4.8%) other complications (lung mycroembolia, heart infarction, lumbal plexus lesion from L2, spinal cord infarction with paraplegia, pneumonia and severe sacral bed-sore). There were 10 (8%) re-interventions following the revision arthroplasty. The result was good or excellent in 80% of operated patients, satisfied in 17%, and bad in 3%. The revision hip procedures are characterized with a high complications incidence rate. Our results are comparable with the results from literature.  相似文献   
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Ghrelin, the endogenous growth hormone secretagogue, has an important role in metabolic homeostasis. It exists in two major molecular forms: acylated (AG) and unacylated (UAG). Many studies suggest different roles for these two forms of ghrelin in energy balance regulation. In the present study, we compared the effects of acute intracerebroventricular administration of AG, UAG and their combination (AG+UAG) to young adult Wistar rats on food intake and central melanocortin system modulation. Although UAG did not affect food intake it significantly increased the number of c-Fos positive neurons in the arcuate (ARC), paraventricular (PVN) and solitary tract (NTS) nuclei. In contrast, UAG suppressed AG-induced neuronal activity in PVN and NTS. Central UAG also modulated hypothalamic expression of Mc4r and Bmp8b, which were increased and Mc3r, Pomc, Agrp and Ucp2, which were decreased. Finally, UAG, AG and combination treatments caused activation of c-Fos in POMC expressing neurons in the arcuate, substantiating a physiologic effect of these peptides on the central melanocortin system. Together, these results demonstrate that UAG can act directly to increase neuronal activity in the hypothalamus and is able to counteract AG-induced neuronal activity in the PVN and NTS. UAG also modulates expression of members of the melanocortin signaling system in the hypothalamus. In the absence of an effect on energy intake, these findings indicate that UAG could affect energy homeostasis by modulation of the central melanocortin system.  相似文献   
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This study describes the application of the laser photoacoustic spectroscopy (PAS) for quantification of total carotenoids (TC) in corn flours and sweetpotato flours. Overall, thirty-three different corn flours and nine sweetpotato flours were investigated. All PAS measurements were performed at room temperature using 488-nm argon laser radiation for excitation and mechanical modulation of 9 and 30 Hz. The measurements were repeated within a run and within several days or months. The UV–Vis spectrophotometry was used as the reference method. The concentration range that allows for the reliable analysis of TC spans a region from 1 to 40 mg kg−1 for corn flours and from 9 to 40 mg kg−1 for sweetpotato flours. In the case of sweetpotato flours, the quantification may extend even to 240 mg kg−1 TC. The estimated detection limit values for TC in corn and sweetpotato flours were 0.1 and 0.3 mg kg−1, respectively. The computed repeatability (n = 3–12) and intermediate precision (n = 6–28) RSD values at 9 and 30 Hz are comparable: 0.1–17.1% and 5.3–14.7% for corn flours as compared with 1.4–9.1% and 4.2–23.0% for sweetpotato flours. Our results show that PAS can be successfully used as a new analytical tool to simply and rapidly screen the flours for their nutritional potential based on the total carotenoid concentration.  相似文献   
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