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1.
The effect of heart rate and variation during cardiac computed tomography (CT) on the examination quality. The purpose of this study is to investigate whether it is possible to predict heart rate and range during enhanced cardiac computed CT scan from previous non-enhanced cardiac CT scan. Electrocardiograph (ECG) files from 112 patients on three types of cardiac 64-slice CT (non-enhanced, prospective ECG-triggered and retrospective ECG-gated enhanced scans) were recorded. The mean heart rate, range (defined as difference between maximal and minimal heart rates) and the range ratio (defined as maximal heart rate divided by minimal heart rate) during the scans were compared. Scan time was 4.8, 4.6, and 7.3 s on non-enhanced, prospective ECG-triggered and retrospective ECG-gated scans, respectively (p < 0.0001). The heart rates were not significantly different (60 ± 9 beats per minute (bpm), 60 ± 9 and 61 ± 10 bpm; p = 0.64). Heart rate on the enhanced scan markedly correlated with that of the non-enhanced scan (r = 0.78 and 0.74). In contrast, the ranges of heart rate were 2 ± 5, 4 ± 8, and 8 ± 21 bpm, with different range ratios (1.04, 1.07, and 1.14; p < 0.0001). Correlation of heart rate ranges between non-enhanced scan versus prospective ECG-triggered scan was low (r = 0.27) and that between non-enhanced scan versus retrospective ECG-gated scan negligible (r = −0.027).Heart rate on enhanced cardiac CT, in most cases, can be predicted from a non-enhanced scan. Heart rate range on enhanced cardiac CT, however, is hard to predict from the non-enhanced scan.  相似文献   

2.
Rats were cooled in water until attaining profound hypothermia and respiratory arrest. After removal from water, 0.5% solution of Na2EDTA was administered intravenously. This led to a drop of blood [Ca2+] by 20-30% from the baseline and promoted recovery of respiration following its arrest lasting 10.3 ± 1.4 min. By the 30th minute of Na2EDTA administration, respiration rate increased to 32.3 ± 5.2 cycles per minute and respiration amplitude reached 68 ± 4% of the baseline level. This effect was observed without special warming of the rats. It was concluded that the period during which the organism maintains viability in respiration arrest and disturbances in respiratory center are still reversible is prolonged under conditions of profound hypothermia.  相似文献   

3.
Maturation of spontaneous cardiac and body movement behavior from 24 to 33 weeks gestational age was characterized prospectively in 168 high-risk fetuses threatening to deliver prematurely. Forty-eight, low-risk fetuses delivering as healthy full-term infants served as a comparison group. Fetuses were classified on the basis of gestational age at time of testing and newborn outcome following delivery (high-risk: premature compromised, premature healthy, term healthy infant; low-risk term healthy). In the high-risk group, the average fetal heart rate was greater and decreased over gestation from 148 to 140 bpm, regardless of outcome. In the low-risk group, it decreased from 145 to 138 bpm. In high- and low-risk groups, the average number of heart rate accelerations greater than or = 15 bpm increased over gestation from 2-3 to 8 while the average number of maternally perceived movements decreased. It was concluded that maturational changes in spontaneous fetal heart rate and maternally perceived body movements in fetuses threatening to deliver prematurely parallel those of low-risk fetuses.  相似文献   

4.
Alternans and arrhythmogenicity were studied in hypokalaemic (3.0 mM K+) Langendorff-perfused murine hearts paced at high rates. Epicardial and endocardial monophasic action potentials were recorded and durations quantified at 90% repolarization. Alternans and arrhythmia occurred in hypokalaemic, but not normokalaemic (5.2 mM K+) hearts (P < 0.01): this was prevented by treatment with lidocaine (10 μM, P < 0.01). Fourier analysis then confirmed transition from monomorphic to polymorphic waveforms for the first time in the murine heart. Alternans and arrhythmia were associated with increases in the slopes of restitution curves, obtained for the first time in the murine heart, while the anti-arrhythmic effect of lidocaine was associated with decreased slopes. Thus, hypokalaemia significantly increased (P < 0.05) maximal gradients (from 0.55 ± 0.14 to 2.35 ± 0.67 in the epicardium and from 0.67 ± 0.13 to 1.87 ± 0.28 in the endocardium) and critical diastolic intervals (DIs) at which gradients equalled unity (from −2.14 ± 0.52 ms to 50.93 ± 14.45 ms in the epicardium and from 8.14 ± 1.49 ms to 44.64 ± 5 ms in the endocardium). While treatment of normokalaemic hearts with lidocaine had no significant effect (P > 0.05) on either maximal gradients (0.78 ± 0.27 in the epicardium and 0.83 ± 0.45 in the endocardium) or critical DIs (6.06 ± 2.10 ms and 7.04 ± 3.82 ms in the endocardium), treatment of hypokalaemic hearts with lidocaine reduced (P < 0.05) both these parameters (1.05 ± 0.30 in the epicardium and 0.89 ± 0.36 in the endocardium and 30.38 ± 8.88 ms in the epicardium and 31.65 ± 4.78 ms in the endocardium, respectively). We thus demonstrate that alternans contributes a dynamic component to arrhythmic substrate during hypokalaemia, that restitution may furnish an underlying mechanism and that these phenomena are abolished by lidocaine, both recapitulating and clarifying clinical findings.  相似文献   

5.
Upper airway obstruction during adulthood is associated with cardiovascular morbidity; cardiovascular consequences of childhood upper airway obstruction are less well established. This study aimed at investigating the effect of childhood upper airway obstruction on respiratory sinus arrhythmia as a measure of cardiac vagal modulation during night‐time sleep. Overnight polysomnography was conducted in 40 healthy children (20 M; age: 7.5 ± 2.6 years; body mass index percentile: 60.7 ± 26.4%) and 40 children with upper airway obstruction (24 M; age: 7.5 ± 2.7 years; body mass index percentile: 65.8 ± 31.9%). We used the phase‐averaging technique to compute respiratory sinus arrhythmia amplitude and phase delay. To study sleep stage effects and the effect of upper airway obstruction, respiratory sinus arrhythmia was measured during all artefact‐free sleep episodes, and after exclusion of respiratory events. A significant increase in respiratory sinus arrhythmia amplitude and phase delay was observed during stage 4 sleep as compared with rapid eye movement sleep in both groups (amplitude: controls = 0.10 ± 0.03 versus 0.07 ± 0.02 s, < 0.01, respectively, and upper airway obstruction = 0.07 ± 0.03 versus 0.05 ± 0.03 s, < 0.05, respectively; phase delay: controls = 3.1 ± 0.1 versus 3.0 ± 0.1 rad, < 0.05, respectively, and upper airway obstruction = 3.13 ± 0.04 versus 3.04 ± 0.08 rad, < 0.01, respectively). A significant association between respiratory sinus arrhythmia and apnea/hypopnea index was observed during stage 2 sleep in children with upper airway obstruction. Compared with healthy controls, a significant decrease in respiratory sinus arrhythmia amplitude during stage 2 sleep was observed in children with upper airway obstruction (0.09 ± 0.03 versus 0.06 ± 0.03 s, < 0.05). However, this difference was not apparent when respiratory events were excluded from analysis. Importantly, respiratory sinus arrhythmia showed a strong negative correlation with body mass index. In conclusion, night‐time respiratory sinus arrhythmia in children is sleep stage dependent and normal during quiet sleep in children with relatively mild upper airway obstruction.  相似文献   

6.
Hematology can be a useful tool for monitoring health status, detecting illnesses, and following the progress of diseases and responses to therapy. Despite advances in fish medicine in recent years, interpretation of fish hematology is often hampered by lack of meaningful reference values and the bewildering diversity of fish species. Serum samples of 40 Acipenser stellatus fish were analyzed (20 male and 20 female) and their serum parameter values were measured in both sexes. Serum biochemical values were determined (mean ± SEM) for sodium (Na; 149.2 ± 1.917 mmol/l), potassium (K; 2.75 ± 0.097 mmol/l), calcium (Ca; 8.293 ± 0.282 mg/dl), phosphorus (P; 12.39 ± 0.267 mg/dl), glucose (Glc; 166.40 ± 8.264 mg/dl), triglyceride (trig; 699.6 ± 22.94 mg/dl), bilirubin (bilirubin; 0.616 ± 0.0234 mg/dl), total protein (TOP; 2.988 ± 0.0842 g/dl), albumin (Alb; 1.218 ± 0.0415 g/dl), cholesterol (CHO; 238.2 ± 11.24 mg/dl), creatinine (CREA; 0.1085 ± 0.0048 mg/dl), and blood urea nitrogen (BUN; 15.32 ± 0.5104 mg/dl). The serum values for bilirubin, Na, P, and CREA were significantly higher in females, whereas BUN and Alb were significantly higher in males. The correlations of coefficients between measured parameters were also determined.  相似文献   

7.
Out of 600 marine fish from the Red Sea belonging to three different species that were collected and examined for microsporidian parasites, 87 (14.5%) fish were found to be infected. The infection was recorded as cysts or xenomas embedded in the gut epithelium and the peritoneal cavity of the three fish species. The highest percent of infection with microsporidian parasites was recorded in Saurida tumbil 19.5% (39/200) followed by Pagrus pagrus 15% (45/300) and the lowest percent of infection was recorded in Epinephelus chlorostigma 3% (three out of 100). After rupture of the cysts, the spores were released and examined by light microscopy. Each spore was elongated to ellipsoidal in shape and possessed a posterior vacuole which is characteristic to phylum Microspora. They measure 1.6 ± 0.5 μm (1.5–2.4 μm) × 1.3 ± 0.1 μm (1.3–2.0 μm) in Saurida tumbil and Pagrus pagrus, respectively. The spores of Pleistophora sp recorded from E. chlorostigma were ovoid to pyriform in shape and measure 1.9 ± 0.5 μm (1.8–2.7 μm) × 1.6 ± 0.4 μm (1.5–2.4 μm).  相似文献   

8.
A drug delivery system that consists of microperforated polyimide microtubes was developed and characterized. Two groups of polyimide tubes were used. One set consisted of microtubes (I.D. = 125 μm) with 32.9 ± 1.7 μm size holes. The second set consisted of larger tubes (I.D. = 1000 μm) with 362–542 μm holes. The number of holes was varied between 1 and 3. The small tubes were loaded with crystal violet (CV) and ethinyl estradiol (EE) and the drug release studies were performed in 0.01 M phosphate buffered saline (PBS) (pH 7.1–7.4) at 37.0 ± 1.0°C for upto 4 weeks. The large tubes were loaded with CV and the drug release was studied in vitro in PBS and also ex vivo in rabbit’s vitreous humor. Linear release rates with R2 > 0.9900 were obtained for all groups with CV and EE. Release rates of 7.8 ± 2.5, 16.2 ± 5.5, and 22.5 ± 6.0 ng/day for CV and 30.1 ± 5.8 ng/day for EE were obtained for small tubes. For large tubes, a release rate of 10.8 ± 4.1, 15.8 ± 4.8 and 22.1 ± 6.7 μg/day was observed in vitro in PBS and a release rate of 5.8 ± 1.8 μg/day was observed ex vivo in vitreous humor.  相似文献   

9.
While 60% of women experiencing recurring episodes of bacterial vaginosis (BV) with vaginal pH ≥ 5 are depleted of resident probiotic lactobacilli, the remainder carry one or more strains of lactobacilli. Their ability to make D-lactic acid is, however, low (3.94 ± 0.72 mM/L) compared to the D-lactic acid produced by strains from healthy vagina with vaginal pH ∼ 4 (8.04 ± 1.07 mM/L) culture supernatant of 0.5 McFarland concentration (P < 0.001).  相似文献   

10.
Haematological and serum biochemical studies of natural population of Synodontis membranacea from Jebba Lake, North Central Nigeria were investigated in order to establish their mean and reference values. Bi-monthly collection of 1,408 live fish samples was carried out between April 2002 and March 2004, using gill nets of various mesh sizes ranging from 5.08 to 10.16 cm. The mean baseline value established for species-specific haematological and serum biochemical parameters were red blood cell (RBC) 3.83 ± 1.49 × 1012 l−1, haemoglobin (HB) 8.38 ± 1.96 g dl−1, and packed cell volume (PCV) 25.65 ± 5.89%; mean cell volume 78.25 ± 37.90 fl; mean cell haemoglobin (MCH) 33.04 ± 12.50 pg; mean cell haemoglobin concentration 26.53 ± 15.18 g dl−1; white blood cell (WBC) 315.65 ± 95.37 × 10−9; agranulocytes (Agr) 82.07 ± 11.38%; monocytes (Mon) 6.37 ± 3.01%; lymphocytes (Lym) 76.49 ± 10.81%; granulocytes (Gran) 40.28 ± 17.48%; neutrophils (Neut) 24.42 ± 10.68%; eosinophils (Eos) 16.14 ± 8.25%; basophils 0.09 ± 0.04%; protein 40.19 ± 7.45 g l−1; albumin 19.78 ± 5.67 g l−1; creatinine 49.71 ± 16.15 μmol l−1; urea 3.05 ± 0.67 nmol l−1; uric acid 0.76 ± 0.33 nmol l−1; glucose 4.24 ± 1.74 mmol l−1; cholesterol 8.46 ± 2.27 mmol l−1; calcium 2.35 ± 0.94 mmol l−1; potassium 13.36 ± 4.45 mmol l−1; sodium 139.39 ± 23.19 mmol l−1; alanine aminotransferase (ALT) 11.79 ± 2.67 U l−1; aspartate aminotransferase 16.80 ± 4.73 U l−1; and alkaline phosphatase 63.01 ± 20.44 U l−1. Only three of these parameters (i.e. neutrophil, glucose and potassium) differed significantly (P > 0.05) on gender basis. Pearson’s correlation coefficients indicated significant relationship of standard length and total weight with RBC, PCV, HB, WBC, Agr, Mon, Lym, Gran, Neut, Eos, sodium, and ALT only. The study has provided baseline haematological and biochemical data for use in health monitoring and productivity of S. membranacea, which would be of great value for future comparative surveys in this era of increased fish culture in Nigeria.  相似文献   

11.
Intraspecific variability among Cystoisospora belli isolates and its clinical implications in human cystoisosporosis have not been established. In this study, the restriction fragment length polymorphisms in a 1.8-kb amplicon of the small subunit ribosomal DNA (SSU rDNA) of the parasite was investigated in 20 C. belli-positive stool samples obtained from 15 HIV-infected patients. Diarrheic syndrome was observed in all patients with cystoisosporosis and the number of diarrheic episodes per patient during hospitalization ranged from 1 to 26 (mean of 9.64 ± 9.30), with a mean duration of 2 to 12 days (mean of 5.90 ± 3 days). Three restriction profiles (RF) were generated with MboII digestion, which were named RFI, RFII, and RFIII. Two isolates obtained from a patient with extraintestinal cystoisosporosis showed distinct restriction profiles with MboII. This study demonstrates that patients can be infected with different C. belli genotypes, and this information may be useful for identifying new C. belli genotypes infecting humans.  相似文献   

12.
Exposure to acute intermittent hypoxia (AIH) evokes persistent increase in respiratory activity that lasts up to 60 min after hypoxic episodes have ceased. This persistent increase in phrenic nerve activity (PNA) is known as phrenic long-term facilitation (LTF). AIH-induced phrenic LTF in anesthetized rats is serotonin dependant. The present study was performed to determine whether microinjection of methysergide (4 mM, 20 ± 5 nl), a broad spectrum 5-HT receptor antagonist, into the caudal raphe nuclei influences phrenic LTF. Peak integrated PNA and respiratory frequency were recorded at 15, 30, and 60 min after five 3-min episodes of normocapnic hypoxia in urethane-anesthetized, vagotomized, paralyzed and ventilated male Sprague–Dawley rats. In control animals, phrenic nerve amplitude was elevated 66.7 ± 8.6% from baseline 1 h after episodic hypoxia, indicating phrenic LTF. Experimental microinjections of methysergide prior to AIH exposure attenuated phrenic LTF (amplitude increase 2.62 ± 2.9% over baseline). We conclude that methysergide microinjections into the caudal raphe region attenuated phrenic LTF induced by AIH, indicating involvement of 5-HT receptor activation at a supraspinal level.  相似文献   

13.
Haematological and serum biochemical values were estimated in blood samples collected from 21 apparently adult golden eagles (Aquila chrysaetos) of both sexes. The mean values of red blood cells, packed cell volume, haemoglobin, white blood cells, heterophils, lymphocytes, monocytes and eosinophils were 1.63 ± 0.11 × 1012/l, 0.47 ± 0.009 l/l, 91.73 ± 1.52 g/l, 24.31 ± 1.97 × 109/l, 4.40 ± 0.22 × 109/l, 16.81 ± 0.65 × 109/l, 0.99 ± 0.19 × 109/l and 2.10 ± 0.30 × 109/l, respectively. The leucocytes had 69.14%, 4.09%, 18.12% and 8.65% lymphocytes, monocytes, heterophils and eosinophils, respectively. The results of serum biochemistry in the golden eagle indicated that the concentrations of glucose, total protein, albumin, total globulin, cholesterol, triglyceride, uric acid, blood urea nitrogen, creatinine, calcium, phosphorous, aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase and alkaline phosphatase were 16.42 ± 0.73 mmol/l, 49.76 ± 1.35 g/l, 20.46 ± 0.79 g/l, 29.30 ± 1.47 g/l, 2.14 ± 0.09 mmol/l, 2.04 ± 0.08 mmol/l, 457.67 ± 97.46 μmol/l, 2.74 ± 0.17 mmol/l, 53.27 ± 3.87 μmol/l, 2.37 ± 0.24 mmol/l, 1.73 ± 0.08 mmol/l, 293.24 ± 18.96 IU/l, 28.21 ± 2.36 IU/l, 411.29 ± 58.37 IU/l, 1,209.89 ± 21.73 IU/l and 67.31 ± 5.29 IU/l, respectively. There were no significant differences between haematological and serum biochemical parameters of male and female golden eagles (P > 0.05).  相似文献   

14.
Chagas disease, caused by Trypanosoma cruzi, is an important public health problem in Latin America. Disturbances in gastrointestinal motility are observed in 15–20% of patients at the chronic phase. We previously observed a decrease in intestinal motility in mice infected with Y strain from T. cruzi. Thus, we decided to test if infection with other T. cruzi strains also caused the intestinal disturbance. Male adult Swiss mice were infected intraperitoneally with CL–Brener clone (CL-B), Brazil strain (Br), or Dm28 clone (Dm) of T. cruzi. All infected mice presented a low cumulative mortality (CL-B, 17%; Br, 8%; Dm, 25%) at 35 days post infection (dpi) and their typical parasitemia curves. Br and Dm groups exhibited a maximal reduction of intestinal motility at 35 dpi (176.8 ± 51.3 and 198.3 ± 52.6 min, respectively), when compared with non-infected mice (90.2 ± 19.5 min). However, CL mice presented the peak of delayed intestinal transit at 12 dpi (191.0 ± 33.3 min), when compared with non-infected mice (105.6 ± 26.4 min), very close to the 15 dpi for the intense alteration (310.2 ± 67.4 min) observed with the Y strain. We clearly demonstrate a reduction in intestinal motility in mice infected with different groups of T. cruzi during the acute phase of the infection. Since Br, Dm, and CL strains presented low mortality rates in adult Swiss mice, a prospective study concerning the chronic intestinal alteration is encouraged, particularly for studies of alternative therapies.  相似文献   

15.
The recently described exchange protein directly activated by cAMP (Epac) has been implicated in distinct protein kinase A-independent cellular signalling pathways. We investigated the role of Epac activation in adrenergically mediated ventricular arrhythmogenesis. In contrast to observations in control conditions (n = 20), monophasic action potentials recorded in 2 of 10 intrinsically beating and 5 of 20 extrinsically paced Langendorff-perfused wild-type murine hearts perfused with the Epac activator 8-pCPT-2′-O-Me-cAMP (8-CPT, 1 μM) showed spontaneous triggered activity. Three of 20 such extrinsically paced hearts showed spontaneous ventricular tachycardia (VT). Programmed electrical stimulation provoked VT in 10 of 20 similarly treated hearts (P < 0.001; n = 20). However, there were no statistically significant accompanying changes (P > 0.05) in left ventricular epicardial (40.7 ± 1.2 versus 44.0 ± 1.7 ms; n = 10) or endocardial action potential durations (APD90; 51.8 ± 2.3 versus 51.9 ± 2.2 ms; n = 10), transmural (ΔAPD90) (11.1 ± 2.6 versus 7.9 ± 2.8 ms; n = 10) or apico-basal repolarisation gradients, ventricular effective refractory periods (29.1 ± 1.7 versus 31.2 ± 2.4 ms in control and 8-CPT-treated hearts, respectively; n = 10) and APD90 restitution characteristics. Nevertheless, fluorescence imaging of cytosolic Ca2+ levels demonstrated abnormal Ca2+ homeostasis in paced and resting isolated ventricular myocytes. Epac activation using isoproterenol in the presence of H-89 was also arrhythmogenic and similarly altered cellular Ca2+ homeostasis. Epac-dependent effects were reduced by Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibition with 1 μM KN-93. These findings associate VT in an intact cardiac preparation with altered cellular Ca2+ homeostasis and Epac activation for the first time, in the absence of altered repolarisation gradients previously implicated in reentrant arrhythmias through a mechanism dependent on CaMKII activity.  相似文献   

16.
Abstract

Despite their enhanced marketplace visibility, validity of wearable photoplethysmographic heart rate monitoring is scarce. Forty-seven healthy participants performed seven, 6-min exercise bouts and completed a valid skin type scale. Participants wore an Omron HR500U (OHR) and a Mio Alpha (MA), two commercial wearable photoplethysmographic heart rate monitors. Data were compared to a Polar RS800CX (PRS). Means and error were calculated between devices using minutes 2–5. Compared to PRS, MA data was significantly different in walking, biking (2.41?±?3.99?bpm and 3.26?±?11.38?bpm, p?<?0.05) and weight lifting (23.30?±?31.94?bpm, p?<?0.01). OHR differed from PRS in walking (4.95?±?7.53?bpm, p?<?0.05) and weight lifting (4.67?±?8.95?bpm, p?<?0.05). MA during elliptical, stair climbing and biking conditions demonstrated a strong correlation between jogging speed and error (r?=?0.55, p?<?0.0001), and showed differences in participants with less photosensitive skin.  相似文献   

17.
The aim of this study was determined the expression of pro inflammatory cytokines in prostate epithelial cells. Furthermore, we analysed the relation between these cytokines and sera PSA levels according the three groups: 0–4, 4–20 and >20 ng/mL. The study was carried out in five normal prostate (NP), 27 benign prostate hyperplastic (BPH) and 18 prostate cancer (PC). Immunohistochemical and Western blot analysis was performed. Serum levels of PSA were assayed by Immulite autoanalyser. The western Blotting analysis revealed an immunoexpression of IL-1α, IL-6 and TNFα in BPH and PC. IL-1α, was absent in NP. Immunohistochemical analysis showed significant high optical density to IL-1α and IL-6 in cancer epithelial cells (19.45 ± 3.25 and 26.2 ± 3.19) compared to normal cells (1.73 ± 1.51 and 4.83 ± 2.65). While, TNFα optical densities were not significant in NP (12.03 ± 2.9), BPH (9.87 ± 3.85) and PC (13.34 ± 2.34). The different profiles of cytokines according sera PSA levels showed a high immunoexpression of the profile (IL-6+, IL-1α+) in BPH patients with PSA between 0–4 and 4–20 ng/mL. However, PC patients with sera PSA between 4 and 20 ng/mL, showed a significant high immunoexpression of the profile (IL-6+, IL-1α−). This data demonstrate a locally production of pro-inflammatory cytokines by prostate epithelial cells and a cross talk between PSA and these cytokines in prostate pathologies.  相似文献   

18.
Aerobic exercises (of sufficient duration and intensity) decreases arterial stiffness. However, the direct relationship between the type of aerobic exercise (i.e. constant versus interval) and the alteration in arterial stiffness has been poorly explored. We evaluated the hemodynamic responses of 11 healthy males (22.5 ± 0.7 years, height 177.7 ± 1.1 cm, body mass 70.5 ± 2.4 kg) following acute constant (CE) and intermittent cycling exercise (IE). Exercise duration and intensity (mean heart rate) were matched during both exercises (142.9 ± 2.4 bpm for CE and 144.2 ± 2.4 bpm for IE). Heart rate (HR) and cardiac output (CO) were measured throughout the whole session, while blood pressure and pulse wave velocity (PWV) were measured during pre exercise and 30 min recovery. Arterial stiffness and cardiac autonomic control were assessed through PWV and heart rate variability, respectively. After IE, lower limb arterial stiffness was significantly and steadily decreased compared to pre exercise value (from 8.6 ± 0.1 to m s−1 to 7.6 ± 0.3 to m s−1 at 30 min) and was lower than after CE (8.2 ± 0.3 m s−1 at 30 min, which did not significantly change compared to pre exercise: 8.7 ± 0.2 m s−1). We hypothesized that the higher HR and lower arterial stiffness after IE were likely due to variations in peripheral vascular changes during the exercise which may trigger the release of endothelial or metabolic vasoactive factors. These data appear to show that IE may result in a greater stimulus for vascular adaptations when compared to CE.  相似文献   

19.
Experiments on Wistar rats showed that exenatide (0.015–0.5 nmol per 100 g body weight) somewhat increased renal excretion of potassium from 7 ± 1 to 16 ± 1 μmol/h/100 g body weight (p < 0.05) in animals with normal serum concentration of glucose (4.6 ± 0.4 mM) and potassium (4.3 ± 0.1 mM). Exenatide dramatically enhanced excretion of potassium under conditions of hyperkalemia (11.4 ± 0.4 mM) produced by intraperitoneal injection of 1.25% KCl solution (5 ml per 100 g body weight). During the fi rst postinjection hour, potassium excretion increased 2-fold and attained 97 ± 11 μmol/h/100 g body weight in comparison with potassium load alone (47 ± 9 μmol/h/100 g body weight, p < 0.05). The data attest to a possible role of peptide regulators in normalization of potassium balance via renal mechanisms.  相似文献   

20.
Huang YX  Xu YL  Yu CX  Li HJ  Yin XR  Wang TS  Wang W  Liang YS 《Parasitology research》2011,109(5):1453-1459
Schistosomiasis remains a major public health problem and it is an immune disease. The schistosome egg is the primary parasite factor responsible for the overt disease. The eggs release the soluble antigen, which induces intensive tissue reaction, a granulomatous reaction to the eggs. If granuloma formation could be suppressed, overt disease might not develop. Praziquantel is an effective antischistosomal drug especially for adult worms. However, whether praziquantel has a suppressing effect on granuloma formation around schistosome eggs directly remains unclear. The purpose of the present study was to investigate the effect of praziquantel, especially administered persistently, on granuloma formation around Schistosoma japonicum eggs in the lung of sensitized mice. Thirty-six mice were divided into three groups averagely. Group A was a control group. First, the mice were injected with schistosomal eggs hypodermically in abdomen, and 10 days later injected with schistosomal eggs intravenously via a tail vein. Group B was a praziquantel short administration group. In addition to the injections of schistosomal eggs as the same of Group A, the mice were administered with praziquantel in a daily dose of 300 mg/kg for 3 days, from 1 day before the intravenous injection of the eggs. Group C was a praziquantel prolonged administration group. In addition to the injections of schistosomal eggs as the same of Group A, the mice were administered with praziquantel in a daily dose of 150 mg/kg for 5 days weekly until the mice were sacrificed. Three mice of each group were sacrificed on days 7, 14, 28, and 56, respectively after the intravenous injection of the eggs, and the lung tissues were fixed with formalin and the slices were HE stained. The granulomas containing eggs in their centers were selected, and 25–30 granulomas from the animals of each group were measured at each time period. The mean areas of egg granulomas of each group were calculated, and the neutrophilic granulocytes, eosinocytes, lymphocytes, fibroblasts, and macrophages within the egg granulomas were counted. The mean numbers of them of each group were calculated. All the data of each group were analyzed and compared statistically. On day 56 after the intravenous injection of the eggs, the mean area of schistosomal egg granulomas in group B was (227.4 ± 728.0) × 103 μm2, less than that of [(297.9 ± 153.3) × 103 μm2] in group A, and the suppression rate was 23.7% (P < 0.05). On days 7, 14, 28, and 56, the mean areas of schistosomal egg granulomas in group C were (575.8 ± 155.6) × 103 μm2, (310.5 ± 854.0) × 103 μm2, (267.7 ± 513.3) × 103 μm2, and (214.9 ± 446.4) × 103 μm2, respectively, significantly less than those of [(692.7 ± 232.6) × 103 μm2, (439.4 ± 165.0) × 103 μm2, (385.7 ± 129.3) × 103 μm2, and (297.9 ± 153.3) × 103 μm2] in group A. The suppression rates were 16.9%, 29.3%, 30.6%, and 27.9%, respectively (P values <0.05). On day 56, the mean numbers of neutrophilic granulocytes were 11.4 ± 5.0 in group A and 5.2 ± 3.1 in group C, respectively, with the suppression rate of 54.4% in group C (P < 0.05). On day 56, the mean numbers of eosinocytes within the egg granulomas were 2.3 ± 2.0, 0.1 ± 0.3, and 0.3 ± 0.6 in groups A, B, and C, respectively, with the suppression rate of 95.7% in group B and 87.0% in group C (P values <0.05). On day 56, the mean numbers of macrophages within egg granulomas were 14.3 ± 6.9 in group C, compared with 18.6 ± 8.2 in group A, the suppression rate was 23.1% (P < 0.05). On day 56, the mean numbers of fibroblasts within the egg granulomas were 6.6 ± 4.4 and 5.8 ± 2.6 in groups B and C, respectively, and compared with 14.3 ± 7.8 in group A, the increasing extents decreased by 53.8% and 59.4%, respectively (P values <0.05). Therefore, the administration of praziquantel, especially the prolonged administration, can suppress the formation of schistosomal egg granulomas, including reduction in the areas of granulomas and suppression of the inflammatory cells and the hyperplasia of fibroblasts within granulomas.  相似文献   

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