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51.
Complexes of boric acid with sodium- and magnesium-salicylates were prepared and analyzed to examine the structural consequences resulting from the coordination of the salicylate ligand in mono- and bis-chelate modes. The complexes were isolated from aqueous solutions and characterized by FTIR (Fourier Transform Infrared), TGA (Thermogravimetric Analysis) and DTA (Differential Thermal Analysis) techniques. Interpretation of their spectral patterns and thermal stabilities established systematic differences and allowed a direct comparison between the mono- and bis-chelate structures. Magnesium bis-salicylatoborate, [Mg(H2O)6][B(Sal)2]·4H2O, was obtained in crystal form and presented as a new type of double-layered material, a unique feature among the salicylatoborate structures reported so far.  相似文献   
52.
Nitric oxide production in newborns under phototherapy.   总被引:2,自引:0,他引:2  
Nitrogen monoxide (NO) is a potent endogenous vasodilator and is involved in cytotoxicity, neurotransmission, and immunological defense mechanisms. Phototherapy has long been known to change the distribution of blood flow throughout the body in newborn infants. The objective of this study was to investigate the effect of phototherapy on NO production in otherwise healthy newborns. Urinary NO levels were measured before and 6 h after phototherapy by a chemiluminescence method using Sievers NOA. Ten newborns (gestational age, 36.4 +/- 3.9 weeks; birth weight, 2863 +/- 677.44 g; postnatal age, 5.1 +/- 2.72 days) were started on phototherapy according to AAP guidelines and urine for NO measurement was collected prior to therapy and 6 h after the commencement of treatment. Urinary NO levels measured during phototherapy were significantly higher (108.8+/-50.69 micromol/mmol creatinine) than the levels measured before phototherapy (73.13+/-34.15 micromol/mmol creatinine; P < 0.05). These results suggest that newborns receiving phototherapy might have increased NO production, which might result in hemodynamic changes. However, further studies on the effects of phototherapy on NO and photorelaxation are needed before reaching firm conclusions.  相似文献   
53.
Two mono-chelate borate complexes, lithium mono-salicylatoborate and sodium mono-glucuronatoborate, are reported for the first time. The complexes were isolated from aqueous solutions and characterized by FTIR (Fourier Transform Infrared) and 13C MAS (Magic Angle Spinning) NMR techniques. Thermal stabilities of the complexes were examined by recording their TGA (Thermogravimetric Analysis) curves. Lithium mono-salicylatoborate, Li[B(Sal)(OH)2], was isolated in crystal form and presented as a novel hybrid metal-organic framework possessing zeolitic structure. X-ray analysis revealed an original crystal structure constructed with solvate-free lithium ions adopting two different types of coordination polyhedra, corner-sharing LiO4 (tetrahedral) and LiO5 (distorted square pyramidal), in the same framework.  相似文献   
54.
The peak procedure is widely used in the study of interval timing with animals. Multiple timing measures can be derived from peak responding. These measures are typically presented as averages across many trials based on the implicit assumption that peak responding is stable throughout the session. We tested this assumption by examining whether peak responding changed over the course of the session in 45 mice that were trained on a fixed-interval 30-s schedule. All common measures of peak responding, except stop times, changed over the course of the session: start times increased, response rates and spreads decreased, and, although less reliably, peak times also shifted rightward. These results are congruent with a motivational interpretation, whereby increased satiety leads to the observed behavioral signature of within-session modulation of timed anticipatory responding.  相似文献   
55.
Intracytoplasmic sperm injection (ICSI) is an important assisted reproductive technology (ART). Due to deployment difficulties and low efficiency of the earlier (conventional) version of ICSI, especially in the mouse, a piezo-assisted ICSI technique had evolved as a popular ART methodology in recent years. An important and remaining problem with this technique, however, is that it requires small amounts of mercury to stabilize the pipette tip when piezoelectric force pulses are applied. To eliminate this problem we developed and tested a completely different and mercury-free technology, called the "Ros-Drill" (rotationally oscillating drill). The technique uses microprocessor-controlled rotational oscillations on a spiked micropipette without mercury or piezo. Preliminary experimental results show that this new microinjection technology gives high survival rate (>70% of the injected oocytes) and fertilization rate (>80% of the survived oocytes), and blastocyst formation rates in early trials (approximately 50% of the survived oocytes). Blastocysts created by Ros-Drill ICSI were transferred into the uteruses of pseudopregnant surrogate mothers and healthy pups were born and weaned. The Ros-Drill ICSI technique is automated and therefore; it requires a very short preliminary training for the specialists, as evidenced in many successful biological trials. These advantages of Ros-Drill ICSI over conventional and piezo-assisted ICSI are clearly demonstrated and it appears to have resolved an important problem in reproductive biology.  相似文献   
56.
Although it does not have a long history of sentinel node evaluation (SLN) in female genital system cancers, there is a growing number of promising study results, despite the presence of some aspects that need to be considered and developed. It has been most commonly used in vulvar and uterine cervivcal cancer in gynecological oncology. According to these studies, almost all of which are prospective, particularly in cases where Technetium-labeled nanocolloid is used, sentinel node detection rate sensitivity and specificity has been reported to be 100%, except for a few cases. In the studies on cervical cancer, sentinel node detection rates have been reported around 80–86%, a little lower than those in vulva cancer, and negative predictive value has been reported about 99%. It is relatively new in endometrial cancer, where its detection rate varies between 50 and 80%. Studies about vulvar melanoma and vaginal cancers are generally case reports. Although it has not been supported with multicenter randomized and controlled studies including larger case series, study results reported by various centers around the world are harmonious and mutually supportive particularly in vulva cancer, and cervix cancer. Even though it does not seem possible to replace the traditional approaches in these two cancers, it is still a serious alternative for the future. We believe that it is important to increase and support the studies that will strengthen the weaknesses of the method, among which there are detection of micrometastases and increasing detection rates, and render it usable in routine clinical practice.  相似文献   
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58.
Beh?et's syndrome (BS) is a relapsing, chronic, inflammatory disease characterized by endothelial dysfunction, atherothromboembogenesis, and leukocytoclastic vasculitis with complex immunologic molecular interactions. Generalized derangements of the lymphocyte and neutrophil populations, activated monocytes, and increased PMNLs motility with upregulated cell surface molecules such as ICAM-1, VCAM-1, and E-selectin, which are found on the endothelial cells, leukocytes, and platelets, have all been demonstrated during the course of BS. Our aim is to investigate the association of serum concentrations of soluble P-selectin in patients with BS, and to evaluate whether disease activity has an effect on their blood levels. This multicenter study included 31 patients with BS (15 men and 16 women) and 20 age- and sex-matched healthy control volunteers (11 men and nine women). Neutrophil count, erythrocyte sedimentation rate, and acute-phase reactants as well as soluble P-selectin levels were determined. The mean age and sex distributions were similar (P > .05) between BS patients (35 years) and control volunteers (36 years). Serum levels of soluble P-selectin in patients with BS (399 +/- 72 ng/mL) were significantly (P < .001) higher when compared with control subjects (164 +/- 40 ng/mL). In addition, active BS patients (453 +/- 37 ng/mL) had significantly (P < .001) elevated levels of soluble P-selectin than those in inactive period (341 +/- 52 ng/mL). This study clearly demonstrated that serum soluble P-selectin levels are increased in BS patients when compared with control subjects, suggesting a modulator role for soluble P-selectin during the course of platelet activation and therefore, atherothrombogenesis formation in BS, especially in active disease.  相似文献   
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60.
The protozoan parasite Trichomonas vaginalis is the causative agent of trichomoniasis, the most widespread nonviral sexually transmitted disease in humans. It possesses hydrogenosomes-anaerobic mitochondria that generate H(2), CO(2), and acetate from pyruvate while converting ADP to ATP via substrate-level phosphorylation. T. vaginalis hydrogenosomes lack a genome and translation machinery; hence, they import all their proteins from the cytosol. To date, however, only 30 imported proteins have been shown to localize to the organelle. A total of 226 nuclear-encoded proteins inferred from the genome sequence harbor a characteristic short N-terminal presequence, reminiscent of mitochondrial targeting peptides, which is thought to mediate hydrogenosomal targeting. Recent studies suggest, however, that the presequences might be less important than previously thought. We sought to identify new hydrogenosomal proteins within the 59,672 annotated open reading frames (ORFs) of T. vaginalis, independent of the N-terminal targeting signal, using a machine learning approach. Our training set included 57 gene and protein features determined for all 30 known hydrogenosomal proteins and 576 nonhydrogenosomal proteins. Several classifiers were trained on this set to yield an import score for all proteins encoded by T. vaginalis ORFs, predicting the likelihood of hydrogenosomal localization. The machine learning results were tested through immunofluorescence assay and immunodetection in isolated cell fractions of 14 protein predictions using hemagglutinin constructs expressed under the homologous SCSα promoter in transiently transformed T. vaginalis cells. Localization of 6 of the 10 top predicted hydrogenosome-localized proteins was confirmed, and two of these were found to lack an obvious N-terminal targeting signal.  相似文献   
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