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131.

Background and Design

In this study we set out to determine the effects of long-term physical training on hemorheological, laboratory parameters, exercise tolerability, psychological factors in cardiac patients participating in an ambulatory rehabilitation program.

Methods

Before physical training, patients were examined by echocardiography, tested on treadmill by the Bruce protocol, and blood was drawn for laboratory tests. The enrolled 79 ischemic heart disease patients joined a 24-week cardiac rehabilitation training program. Blood was drawn to measure hematocrit (Hct), plasma and whole blood viscosity (PV, WBV), red blood cell (RBC) aggregation and deformability. Hemorheological, clinical chemistry and psychological measurements were repeated 12 and 24 weeks later, and a treadmill test was performed at the end of the program.

Results

After 12 weeks Hct, PV, WBV and RBC aggregation were significantly decreased, RBC deformability exhibited a significant increase (p<0.05). Laboratory parameters (triglyceride, uric acid, hsCRP and fibrinogen) were significantly decreased (p<0.05). After 24 weeks the significant results were still observed. By the end of the study, IL-6 and TNF-α levels displayed decreasing trends (p<0.06). There was a significant improvement in MET (p<0.001), and the BMI decrease was also significant (p<0.05). The vital exhaustion parameters measured on the fatigue impact scale indicated a significant improvement in two areas of the daily activities (p<0.05).

Conclusions

Regular physical training improved the exercise tolerability of patients with ischemic heart disease. Previous publications have demonstrated that decreases in Hct and PV may reduce cardiovascular risk, while a decrease in RBC aggregation and an increase in deformability improve the capillary flow. Positive changes in laboratory parameters and body weight may indicate better oxidative and inflammatory circumstances and an improved metabolic state. The psychological findings point to an improvement in the quality of life.  相似文献   
132.
Highlights? NBD1 and NBD1-CL4 interface instability limit CFTR conformational maturation ? ΔF508 mutation thermodynamically and kinetically destabilizes NBD1 ? Stabilization of ΔF508-NBD1 is insufficient for CFTR-coupled domain folding ? ΔF508 CFTR folding and function require both NBD1 and NBD1-CL4 stabilization  相似文献   
133.
Fermented bamboo shoots are popular traditional food items of various ethnic groups of the northeastern India, especially in Manipur State. Dendrocalamus hamiltonii is an economically important bamboo species used to produce fermented bamboo shoots. We studied genetic variability of this bamboo species in Chandel and Imphal-East (commercial production districts), using AFLP molecular markers. Each of the selected primers detected polymorphisms and 1614 (95.8%) were found to be polymorphic. Cluster analysis based on Dice similarity coefficients using UPGMA differentiated the populations into two major groups. Principal coordinate analysis based on the AFLP data clearly separated the populations according to their genetic diversity and antioxidant activity. Four primers were tested through multiple regression analysis to identify marker-trait association between AFLP data and biochemical attributes, i.e., antioxidant activity and total cyanide content. The 273 bp generated by EcoRI-AAG(Joe)/MseI-CTC showed high positive correlation with antioxidant activity (r = 0.729, P < 0.01). The 396 bp generated by EcoRI-AAC(Ned)/MseI-CTG were negatively correlated with cyanide content (r = -0.694, P < 0.01). Thus, we found association of DNA markers with antioxidant activities and total cyanide content. These results could be of use for the identification of superior genotypes with desirable traits.  相似文献   
134.
Acute spinal cord injury (ASCI) is a devastating event that can have severe hemodynamic consequences, depending on location and severity of the lesion. Knowledge of hyperacute hemodynamic changes is important for researchers using porcine models of thoracic ASCI. The goal of this study was to determine the hyperacute hemodynamic changes observed after ASCI when using pigs as their own controls. Five Yucatan gilts were anesthetized, and a dorsal laminectomy performed at T10-T12. Standardized blunt trauma was applied for 5 consecutive min, and hemodynamic variables were collected 5 min before ASCI, and at 2, 4, 6, 8, 10, 20, 30, 60, 80 and 120 min after ASCI. Arterial blood gas samples were collected at 60 min and 10 min before, and at 30 min and between 120 and 240 min after ASCI. Parametric data were analyzed using a mixed effects model with time point as the fixed factor and subject as the random factor. We found no effect on heart rate, pulse pressure, SpO2, EtCO2, and respiratory rate between baseline and timepoints after ASCI. Diastolic arterial pressure, mean arterial pressure, and systolic arterial pressure fell significantly by 18%, 16%, and 15%, respectively, at 2 min after ASCI. However, none of the decrements in arterial pressures resulted in hypotension at any time point. Heart rate did not change significantly after ASCI. Blood glucose progressively increased to 50% above baseline between 120 and 240 minutes after ASCI. Low thoracic ASCI caused a consistent and statistically significant but clinically minor hyperacute decrease in arterial pressures (-15%) that did not produce hypotension or metabolic changes suggestive of tissue hypoperfusion. Our findings using this model suggest that mean arterial pressures should be maintained above 85 mm Hg prior to spinal trauma in order to avoid hypotensive states after ASCI.Abbreviations and Acronyms: ASCI, acute spinal cord injury; BE, base excess; BT, core body temperature; CRI, continuous rate infusion; DAP, diastolic arterial pressure; EtCO2, expired partial pressure of carbon dioxide; EtISO, end tidal isoflurane concentration; FLK, fentanyl lidocaine ketamine; Glu, glucose; HR, heart rate; Hb, hemoglobin; Lac, lactate; LRS, lactated Ringer’s solution; MAP, mean arterial pressure; MLK, morphine lidocaine ketamine; PaCO2, arterial partial pressure of carbon dioxide; PaO2, arterial partial pressure of oxygen; PP, pulse pressure; RR, respiratory rate; SAP, systolic arterial pressure; SCI, spinal cord injury  相似文献   
135.
Findings. Specific [3H]flunitrazepam binding to neuronal-type sites was significantly lower in anterior cingulate cortex, hippocampus, somatomotor cortex, cerebellar cortex, and globus pallidus in small postmortem samples of schizophrenic brains than in non-schizophrenic controls. Four of these five brain regions were reported by others to exhibit atrophy and/or neuronal loss in schizophrenia.Interpretation: Selective loss of hippocampal pyramidal neurons in postmortem schizophrenic brains has been reported (11). Pyramidal neurons are known to be glutamatergic (14, 26) and to exhibit high densities of benzodiazepine binding sites (25,31). Glutamatergic neurons are known to be abundant in most layers of the cerebral cortex, and most of these are pyramidal neurons (26). All layers of the cerebral cortex display high densities of benzodiazepine binding sites (24,25,31). The number of large pyramidal cells is little affected in most layers of the anterior cingulate cortex, but the number of small neurons is significantly lower, particularly in layer II (10). Pyramidal neurons range in size from very large to very small, and many very small pyramidal cells are often counted, together with small stellate neurons, as granule cells (28). Further, non-pyramidal glutamatergic neurons are reportedly also found in cerebral cortex (26). Thus, it seems possible that the large reduction in [3H]flunitrazepam binding we find in anterior cingulate cortex reflects the selective loss of glutamatergic neurons. The hypothesis that selective loss of glutamatergic neurons form various brain regions is associated with major psychoses can be easily tested by immunohistochemical studies of these regions using glutamate- and GABA-specific antibodies.  相似文献   
136.
Since the triiodothyronine (T3) shifts the tissue metabolism to oxidative direction, one should await that in hyperthyreoidism caused by T3 an oxidosis will be formed, whilst in hypothyreoidism called forth by subtotal thyreoidectomy, redosis will be emerged. However, according to our experiments these interrelationships proved to be inverse. These "paradoxal" changes of redox-state are the consequences of the flowing redox compensations elicited by the tissue redox-buffer capacity (RBC). The pathomechanism can be modelled with differential equation (computer analysis). The redox-state changes are characteristics in each tissues. Between the RBC of the tissue and the shift of redox-state potential (E'0) there is a negative correlation. As an autoregulatory mechanims, the redosis formed in hyperthyreoidism will increase the hormone synthesis in the thyroid gland, while the oxidosis after hypothyreoidism will decrease the synthesis. In other words, these processes strengthen each other. Changes of the heart frequency show correlation with the E'0, and can be described by differential equation. Our theoretical model for the redox regulation might answer also the question of the reversibility-irreversibility range of the autoregulation in the pathomechanism.  相似文献   
137.
The meiotic drive characteristics of the In(1)sc4Lsc8R/Y system have been examined by genetic analysis and by light and electron microscopy. sc4sc8/Y males show a direct correlation between nondisjunction frequency and meiotic drive. Temperature-shift experiments reveal that the temperature-sensitive period for nondisjunction is at meiosis, whereas that for meiotic drive has both meiotic and post-meiotic components. Cytological analyses in the light and electron microscopes reveal failures in spermiogenesis in the testes of sc4sc8 males. The extent of abnormal spermatid development increases as nondisjunction becomes more extreme.  相似文献   
138.
The hendecapeptide, Ala-Val-Lys-Lys-Tyr-Leu-Asn-Ser-Val-Leu-Thr-NH2, corresponding to sequence 18–28 of chicken vasoactive intestinal peptide (VIP), was synthesized stepwise, starting with the C-terminal residue. The in situ technique was applied; o-nitrophenyl esters and p-nitrophenyl esters were used for acylation. The product was compared with, and found indistinguishable from, the C-terminal cyanogen bromide fragment of natural chicken-VIP. Some pharmacological properties of the hendecapeptide were also determined. In two separate experiments, the chain of the hendecapeptide was further lengthened to encompass residues 14–28 of chicken-VIP but with leucine and norleucine in place of methionine in position 17. The two pentadecapeptides showed biological activities comparable to those of the C-terminal pentadecapeptide fragment of porcine VIP or its 17-norleucine analog.  相似文献   
139.
The problems of the Segregation-Distorter system are approached and unified in terms of an orthodox quantitative genetic system. It is shown that the SD system involves positive and negative modifier genes of varying strengths, that there is no major Stabiliser gene, and that the Activator gene is not unique. It is further argued that the SD phenomenon is mainly male limited, with "female effects" being of small magnitude.  相似文献   
140.
Telomeric satellite DNA functions in regulating recombination   总被引:18,自引:4,他引:14  
Molecular and cytogenetical analyses of three sibling species of Australian grasshopper, Atractomorpha australis, A. species-1 and A. similis, resolves one of the long standing problems of highly repeated DNA. In this system satellite DNA functions in regulating the level and position of recombination, irrespective of whether the repeated DNA is located in telomeric or centric regions. — Even though the three species do not differ in their euchromatic genome sizes, their relative DNA contents are 1.00/1.10/ 1.41, the difference in genome size being due solely to visible centric or telomeric blocks of heterochromatin. — Antibiotic analytical and preparative ultracentrifugation, in situ hybridization and renaturation kinetic analyses reveal that a large cryptic satellite of A. similis constitutes the heterochromatic telomeric blocks of nearly all autosomes and that the DNA of this satellite is highly repeated. — Comparison of these grasshopper data with published literature of heterochromatic rearrangements in Drosophila and with heterochromatin distribution and recombination patterns in diploid plant species reveals that in every case heterochromatin is implicated in some form of alteration in the meiotic recombination system.  相似文献   
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