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1.
The present study was performed to describe the incidence and risk factors for nosocomial infections (NIs) in the intensive care units of a University hospital. From January to July 2002, 454 patients from Medical and Surgical Intensive Care Unit (MICU and SICU) were observed in the active, targeted, prospective surveillance study. Risk factors for NIs were found by logistic regression analysis. Two hundred and eighteen NIs were recorded in 149 of 454 screened patients. The overall incidence rate was calculated as 33% in the ICUs. The incidence was 39% in MICU and 29% in SICU. The most frequent nosocomial infection observed in MICU, and SICU was pneumonia (42%), and surgical wound infection (31%), respectively. Extrinsic risk factors were urinary catheter, mechanical ventilation, total parenteral nutrition, entubation, antimicrobial treatment prior to the NI, nasogastric cathater and central catheter. The highest intrinsic risk factor was unconsciousness in MICU, respiratory failure in SICU. This high NI rates may be reduced by timely feedback of data for infection control activities. The recognition of risk factors for NIs is an important tool for the identification and development of interventions to minimize such risks in the ICU's.  相似文献   

2.
Serum interleukin 15 (IL-15) levels were measured in 77 patients who were consecutively admitted to our intensive care unit. Postoperative enterocolitis occurred in four patients and Methicillin-resistant Staphylococcus aureus (MRSA), but not Clostridium difficile, was identified in the faecal specimens from these patients. The IL-15 levels in the patients with MRSA enterocolitis were significantly elevated compared with those of other MRSA infections without enterocolitis including pneumonia (n=6) and cholangitis (n=1), and other MRSA non-colonized patients (n=66) (21.2+/-5.2 pg/ml vs 4.3+/-0.2, 4.3+/-0.5). Notably, an increase in serum IL-15 was observed just before clinical manifestation of severe diarrhoea. Our findings suggest that IL-15 may be associated in the pathogenesis of postoperative enterocolitis and its serum level may be a severity indicator of the disease.  相似文献   

3.
A simple mathematical model for studying mechanism-based inhibitors (MBIs) is presented. The mathematical equations are deduced for an experimental protocol consisting of a first incubation of the enzyme in the presence of MBI followed by a washing protocol to eliminate free MBI. Finally enzyme activity (initial velocity) is measured with specific substrate. The representation of the final equation obtained is a straight line, and the MBI-specific association constant of velocity (k) can be calculated from its slope. The mathematical model was then challenged with the effect of 18-ethynyl-11-deoxycorticosterone (18-EtDOC) as an MBI on aldosterone biosynthesis from 11-deoxycorticosterone (DOC) in rat adrenal mitochondria. The last step of the mitochondrial biosynthesis of aldosterone consists of the conversion of DOC into corticosterone (B) or 18-hydroxy-11-deoxycorticosterone (18-OHDOC), and both steroids can then be transformed into aldosterone. The k (mM(-1) x min(-1)) values obtained for 18-EtDOC were: 451 +/- 36 for DOC to aldosterone; 177 +/- 16 for B to aldosterone; 175 +/- 15 for 18-OHDOC to aldosterone; and 2.7 +/- 0.2 for DOC to B. These results show that this MBI practically does not affect the metabolism of DOC to B in our enzyme preparation and that conversions of B and 18-OHDOC into aldosterone are catalyzed by the same enzyme.  相似文献   

4.
Sixty-six hospitalized patients became infected with a single strain of multiply resistant Pseudomonas aeruginosa over a 22-month period. The catheterized urinary tract was the site of the infection in 59 patients (89%). The outbreak was confined to a urology ward until an infected patient from this ward spent 2 weeks in the surgical intensive care unit (SICU). Subsequently patients who acquired the infection in the SICU were discharged to surgical wards throughout the hospital. Urine measuring containers and urometers used in the SICU were the reservoir of the P. aeruginosa; daily sterilization of this equipment terminated the outbreak. Urometers appeared to be the reservoir of the epidemic strain in subsequent outbreaks. Five patients were still infected when they were readmitted 3 to 12 months after the first admission, and therefore represented an additional reservoir of infection.  相似文献   

5.
Neuromuscular and hormonal adaptations to prolonged strength training were investigated in nine elite weight lifters. The average increases occurred over the 2-yr follow-up period in the maximal neural activation (integrated electromyogram, IEMG; 4.2%, P = NS), maximal isometric leg-extension force (4.9%, P = NS), averaged concentric power index (4.1%, P = NS), total weight-lifting result (2.8%, P less than 0.05), and total mean fiber area (5.9%, P = NS) of the vastus lateralis muscle, respectively. The training period resulted in increases in the concentrations of serum testosterone from 19.8 +/- 5.3 to 25.1 +/- 5.2 nmol/l (P less than 0.05), luteinizing hormone (LH) from 8.6 +/- 0.8 to 9.1 +/- 0.8 U/l (P less than 0.05), follicle-stimulating hormone (FSH) from 4.2 +/- 2.0 to 5.3 +/- 2.3 U/l (P less than 0.01), and testosterone-to-serum sex hormone-binding globulin (SHBG) ratio (P less than 0.05). The annual mean value of the second follow-up year for the serum testosterone-to-SHBG ratio correlated significantly (r = 0.84, P less than 0.01) with the individual changes during the 2nd yr in the averaged concentric power. The present results suggest that prolonged intensive strength training in elite athletes may influence the pituitary and possibly hypothalamic levels, leading to increased serum levels of testosterone. This may create more optimal conditions to utilize more intensive training leading to increased strength development.  相似文献   

6.
ObjectiveHyperglycemia often occurs after the transition from intravenous insulin infusion (IVII) to subcutaneous insulin. Weight-based basal insulin initiated earlier in the course of IVII in the medical intensive care unit (MICU), and a weight-based basal-bolus regimen after IVII, can potentially improve post-IVII glycemic control by 48 hours.MethodsThis prospective study included 69 patients in MICU who were on IVII for ≥24 hours. Exclusions were end-stage renal disease, type 1 diabetes mellitus, and the active use of vasopressors. The intervention group received weight-based basal insulin (0.2-0.25 units/kg) with IVII and weight-based bolus insulin after IVII. The control group received current care. The primary end points were glucose levels at specific time intervals up to 48 hours after IVII.ResultsThere were 25 patients in the intervention group and 44 in the control group. The mean age of the patients was 59 ± 15 years, 32 (47%) were men, and 52 (78%) had prior diabetes mellitus. The 2 groups were not different (acute kidney injury/chronic kidney disease, pre-existing diabetes mellitus, illness severity, or nothing by mouth status after IVII), except for the steroid use, which was higher in the control group than in the intervention group (34% vs 12%, respectively). Glucose levels were not lower until 36 to 48 hours after IVII (166.8 ± 39.1 mg/dL vs 220.0 ± 82.9 mg/dL, P < .001). When controlling for body mass index, nutritional status, hemoglobin A1C, and steroid use, glucose level was lower starting at 12 to 24 hours out (166.87 mg/dL vs 207.50 mg/dL, P = .015). The frequency of hypoglycemia was similar between the 2 groups (5.0% vs 7.1%). The study did not reach target enrollment.ConclusionThe addition of weight-based basal insulin during, and basal-bolus insulin immediately after, IVII in MICU results in better glycemic control at 24 hours after IVII with no increased hypoglycemia.  相似文献   

7.
Plasma levels of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), stable metabolites of two prostanoids with opposing biological effects, TXA2 and prostacyclin, were measured by radioimmunoassay in normal pregnancy (controls) and pregnancy complicated by hypertension (PIH) from 32 to 36 (Period 1; P1) and from 36 to 40 (Period 2; P2) weeks of gestation. The plasma concentration of each compound in the control subjects was 265.6 +/- 58.4 (TXB2), 132.4 +/- 16.5 (6-keto-PGF1 alpha) for P1 (n = 10) and 142.6 +/- 11.8 (TXB2), 68.5 +/- 5.2 (6-keto-PGF1 alpha) for P2 (n = 10) respectively (pg/ml, mean +/- s.e). In the patients with PIH, TXB2 concentrations increased moderately for P1 (419.2 +/- 21.2; n = 7) and significantly (p less than 0.005) for P2 (452.8 +/- 31.0; n = 7) respectively (pg/ml, mean +/- s.e), while the plasma levels of 6-keto-PGF1 alpha revealed a slight to moderate decrease both for P1 (84.5 +/- 4.0; n = 7) and P2 (59.7 +/- 8.1; n = 7) respectively (pg/ml, mean +/- s.e). The physiological balance of TXB2 to 6-keto-PGF1 alpha was significantly greater (p less than 0.005) in the patients with PIH, where the TXB2/6-keto-PGF1 alpha ratio was 5.2 +/- 0.7 for P1 and 9.4 +/- 2.3 for P2 respectively (mean +/- s.e) compared with that of the controls, where it was 2.4 +/- 0.4 for P1 and 2.0 +/- 0.2 for P2 respectively (mean +/- s.e).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
OBJECTIVE--To compare the efficacy of home based care with standard hospital care in treating serious mental illness. DESIGN--Randomised controlled trial. SETTING--South Southwark, London. PATIENTS--189 patients aged 18-64 living in catchment area. 92 were randomised to home based care (daily living programme) and 97 to standard hospital care. At three months'' follow up 68 home care and 60 hospital patients were evaluated. MAIN OUTCOME MEASURES--Use of hospital beds, psychiatric diagnosis, social functioning, patients'' and relatives'' satisfaction, and activity of daily living programme staff. RESULTS--Home care reduced hospital stay by 80% (median stay six days in home care group, 53 days in hospital group) and did not increase the number of admissions compared with hospital care. On clinical and social outcome there was a non-significant trend in favour of home care, but both groups showed big improvements. On the global adjustment scale home care patients improved by 26.8 points and the hospital group by 21.6 points (difference 5.2; 95% confidence interval -1.5 to 12). Other rating scales showed similar trends. Home care patients required a wide range of support in areas such as housing, finance, and work. Only three patients dropped out from the programme. CONCLUSIONS--Home based care may offer some slight advantages over hospital based care for patients with serious mental illness and their relatives. The care is intensive, but the low drop out rate suggests appreciation. Changes to traditional training for mental health workers are required.  相似文献   

9.
Serum levels of thyrotrophin (TSH), prolactin (PRL), free thyroxine (FT4) and free triiodothyronine (FT3) were determined before and after physical exercise in 21 normal male subjects. The subjects were divided into 3 groups as follows: group I--light exercise (exercise on the Mijnhardt bicycle ergometer at 100 Watts for 15 min); group II--moderate exercise (a 5 km marathon); group III--heavy exercise (a 10 km marathon). In group I, TSH level rose from 1.96 +/- 0.42 mu u/ml (mean +/- SEM) to 2.52 +/- 0.30 mu u/ml (p less than 0.01), and PRL levels rose from 11.0 +/- 2.0 ng/ml to 19.0 +/- 5.2 ng/ml (p less than 0.01). In group II, TSH rose from 2.11 +/- 0.51 mu u/ml to 2.62 +/- 0.56 mu u/ml (p less than 0.05), and PRL rose from 11.2 +/- 1.6 ng/ml to 24.0 +/- 5.2 ng/ml (p less than 0.01). In group III, TSH rose from 2.01 +/- 0.41 mu u/ml to 2.36 +/- 0.45 mu u/ml (p less than 0.02), and PRL rose from 12.1 +/- 2.0 ng/ml to 47.7 +/- 9.3 ng/ml (p less than 0.01). The serum levels of FT4 showed different results among the three groups: Group I showed an increased response from 1.60 +/- 0.12 ng/dl to 1.72 +/- 0.12 ng/dl (p less than 0.01); Group II showed no significant difference; and group III demonstrated a diminished response from 1.61 +/- 0.14 ng/dl to 1.45 +/- 0.16 ng/dl (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.

Background

Psychiatry has been consistently shown to be a profession characterised by ‘high-burnout’; however, no nationwide surveys on this topic have been conducted in Japan.

Aims

The objective of this study was to estimate the prevalence of burnout and to ascertain the relationship between work environment satisfaction, work-life balance satisfaction and burnout among psychiatrists working in medical schools in Japan.

Method

We mailed anonymous questionnaires to all 80 psychiatry departments in medical schools throughout Japan. Work-life satisfaction, work-environment satisfaction and social support assessments, as well as the Maslach Burnout Inventory (MBI), were used.

Results

Sixty psychiatric departments (75.0%) responded, and 704 psychiatrists provided answers to the assessments and MBI. Half of the respondents (n = 311, 46.0%) experienced difficulty with their work-life balance. Based on the responses to the MBI, 21.0% of the respondents had a high level of emotional exhaustion, 12.0% had a high level of depersonalisation, and 72.0% had a low level of personal accomplishment. Receiving little support, experiencing difficulty with work-life balance, and having less work-environment satisfaction were significantly associated with higher emotional exhaustion. A higher number of nights worked per month was significantly associated with higher depersonalisation.

Conclusions

A low level of personal accomplishment was quite prevalent among Japanese psychiatrists compared with the results of previous studies. Poor work-life balance was related to burnout, and social support was noted to mitigate the impact of burnout.  相似文献   

11.
The prevalence of vancomycin-resistant enterococci (VRE) colonization or infection in the hospital setting has increased globally. Many previous studies had analysed the risk factors for acquiring VRE, based on cross-sectional studies or prevalent cases. However, the actual incidence of and risk factors for VRE remain unclear. The present study was conducted in order to clarify the incidence of and risk factors for VRE in the intensive care unit (ICU). From 1st April 2008 to 31st March 2009, all patients admitted to a surgical ICU (SICU) were put on active surveillance for VRE. The surveillance cultures, obtained by rectal swab, were taken on admission, weekly while staying in the SICU, and on discharge from the SICU. A total of 871 patients were screened. Among them, 34 were found to carry VRE before their admission to the SICU, and 47 acquired VRE during their stay in the SICU, five of whom developed VRE infections. The incidence of newly acquired VRE during ICU stay was 21.9 per 1000 patient-days (95% confidence interval [CI], 16.4–29.1). Using multivariate analysis by logistic regression, we found that the length of ICU stay was an independent risk factor for new acquisition of VRE. In contrast, patients with prior exposure to first-generation cephalosporin were significantly less likely to acquire VRE. Strategies to reduce the duration of ICU stay and prudent usage of broad-spectrum antibiotics are the keys to controlling VRE transmission.  相似文献   

12.
The size of small cell lung carcinoma (SCLC) cells has often been ambiguously defined as one and a half to four times that of a lymphocyte. The purpose of this study was to determine the ratio of nuclear diameter (ND) of SCLC cells to that of lymphocytes in the same tissue sections and to assess whether the size of SCLC cells correlates with the size of tumor specimens and crush artifact. The overall mean ND (microns +/- SD) of SCLC cells was 9.2 +/- 2.1, found in 36 oat cell carcinomas (OAT, 1,800 nuclei) and 16 intermediate cell carcinomas (INT, 800 nuclei). The mean ND of OAT and INT cells was 8.1 +/- 1.3 and 11.6 +/- 1.5, respectively. The mean ND of lymphocytes (2,600 nuclei) was 5.2 +/- 0.3. The overall mean of ND ratios (+/- SD) between SCLC cells and lymphocytes was 1.8 +/- 0.4 (median, 1.7), 1.6 +/- 0.2 for OAT and 2.2 +/- 0.3 for INT. The mean size of the 52 SCLC biopsy specimens was 0.6 +/- 0.9 cm. Of all the biopsies, 84.6% (n = 44) showed various degrees of tissue crushing. The ND of SCLC cells was associated with specimen size (P = .004) and the degree of tissue crushing (P = .001). Therefore, our findings further support the hypothesis that OAT should be considered the effect of artifact rather than a true variant of SCLC and that the ND of SCLC cells is approximately two times that of lymphocytes.  相似文献   

13.
The objective of this study was to determine whether arterial PCO2 (PaCO2) decreases or remains unchanged from resting levels during mild to moderate steady-state exercise in the dog. To accomplish this, O2 consumption (VO2) arterial blood gases and acid-base status, arterial lactate concentration ([LA-]a), and rectal temperature (Tr) were measured in 27 chronically instrumented dogs at rest, during different levels of submaximal exercise, and during maximal exercise on a motor-driven treadmill. During mild exercise [35% of maximal O2 consumption (VO2 max)], PaCO2 decreased 5.3 +/- 0.4 Torr and resulted in a respiratory alkalosis (delta pHa = +0.029 +/- 0.005). Arterial PO2 (PaO2) increased 5.9 +/- 1.5 Torr and Tr increased 0.5 +/- 0.1 degree C. As the exercise levels progressed from mild to moderate exercise (64% of VO2 max) the magnitude of the hypocapnia and the resultant respiratory alkalosis remained unchanged as PaCO2 remained 5.9 +/- 0.7 Torr below and delta pHa remained 0.029 +/- 0.008 above resting values. When the exercise work rate was increased to elicit VO2 max (96 +/- 2 ml X kg-1 X min-1) the amount of hypocapnia again remained unchanged from submaximal exercise levels and PaCO2 remained 6.0 +/- 0.6 Torr below resting values; however, this response occurred despite continued increases in Tr (delta Tr = 1.7 +/- 0.1 degree C), significant increases in [LA-]a (delta [LA-]a = 2.5 +/- 0.4), and a resultant metabolic acidosis (delta pHa = -0.031 +/- 0.011). The dog, like other nonhuman vertebrates, responded to mild and moderate steady-state exercise with a significant hyperventilation and respiratory alkalosis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Hypoperfusion of active skeletal muscle elicits a reflex pressor response termed the muscle metaboreflex. Dynamic exercise attenuates spontaneous baroreflex sensitivity (SBRS) in the control of heart rate (HR) during rapid, spontaneous changes in blood pressure (BP). Our objective was to determine whether muscle metaboreflex activation (MRA) further diminishes SBRS. Conscious dogs were chronically instrumented for measurement of HR, cardiac output, mean arterial pressure, and left ventricular systolic pressure (LVSP) at rest and during mild (3.2 km/h) or moderate (6.4 km/h at 10% grade) dynamic exercise before and after MRA (via partial reduction of hindlimb blood flow). SBRS was evaluated as the slopes of the linear relations (LRs) between HR and LVSP during spontaneous sequences of at least three consecutive beats when HR changed inversely vs. pressure (expressed as beats x min(-1) x mmHg(-1)). During mild exercise, these LRs shifted upward, with a significant decrease in SBRS (-3.0 +/- 0.4 vs. -5.2 +/- 0.4, P<0.05 vs. rest). MRA shifted LRs upward and rightward and decreased SBRS (-2.1 +/- 0.1, P<0.05 vs. mild exercise). Moderate exercise shifted LRs upward and rightward and significantly decreased SBRS (-1.2 +/- 0.1, P<0.05 vs. rest). MRA elicited further upward and rightward shifts of the LRs and reductions in SBRS (-0.9 +/- 0.1, P<0.05 vs. moderate exercise). We conclude that dynamic exercise resets the arterial baroreflex to higher BP and HR as exercise intensity increases. In addition, increases in exercise intensity, as well as MRA, attenuate SBRS.  相似文献   

15.
Molecular properties of cytosolic Ah receptors from livers of Sprague-Dawley rats and C57BL/6N mice were assessed by velocity sedimentation on sucrose gradients and by gel permeation chromatography on Sephacryl S-300. Analyses were done under conditions of both moderate ionic strength (presence of 0.1 M KCl) and high ionic strength (0.4 M KCl). [3H] 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) was used as the radioligand. In conditions of moderate ionic strength the receptor from Sprague-Dawley rat liver sedimented at 8.8 +/- 0.05 S, had a Stokes radius of 7.0 +/- 0.21 nm, and an apparent relative molecular mass (Mr) of 257,000 +/- 7,700. In conditions of high ionic strength the Ah receptor from rat hepatic cytosol dissociated to a [3H]TCDD-binding subunit which sedimented at 5.6 +/- 0.58 S, had a Stokes radius of 5.2 +/- 0.24 nm, and an apparent Mr of 121,000 +/- 5,600. The Ah receptor from liver of C57BL/6N mice, in moderate ionic strength conditions, sedimented at 9.4 +/- 0.54 S, had a Stokes radius of 7.1 +/- 0.12 nm, and an apparent Mr of 277,000 +/- 4,800. Whereas the Ah receptor from rat liver readily dissociated into a [3H]TCDD-binding subunit during brief exposure to 0.4 M KCl, the mouse Ah receptor resisted dissociation. When exposed to 0.4 M KCl for 2 h, the mouse Ah receptor remained at the same molecular size that it had exhibited in moderate ionic strength conditions. Prolonged exposure (16 h) to 0.4 M KCl prior to analysis partially converted the mouse Ah receptor into a smaller [3H]TCDD-binding subunit which sedimented at 4.9 +/- 0.07 S, had a Stokes radius of 5.2 +/- 0.19 nm, and an apparent Mr of 105,000 +/- 3,800. The potency of seven different Ah receptor agonists in competing with [3H]TCDD for specific receptor sites was slightly different in mouse cytosol than in rat cytosol. By criteria of size, response to high ionic strength environments, and ligand binding preferences the mouse and rat Ah receptors appear to be similar but not identical molecular species.  相似文献   

16.
Hyperglycemia is an important predictor of cardiovascular mortality in patients with diabetes. We investigated the hypothesis that diabetes or acute hyperglycemia attenuates the reduction of myocardial infarct size produced by activation of mitochondrial ATP-regulated potassium (K(ATP)) channels. Acutely instrumented barbiturate-anesthetized dogs were subjected to a 60-min period of coronary artery occlusion and 3 h of reperfusion. Myocardial infarct size (triphenyltetrazolium chloride staining) was 25 +/- 1, 28 +/- 3, and 25 +/- 1% of the area at risk (AAR) for infarction in control, diabetic (3 wk after streptozotocin-alloxan), and hyperglycemic (15% intravenous dextrose) dogs, respectively. Diazoxide (2.5 mg/kg iv) significantly decreased infarct size (10 +/- 1% of AAR, P < 0.05) but did not produce protection in the presence of diabetes (28 +/- 5%) or moderate hyperglycemia (blood glucose 310 +/- 10 mg/dl; 23 +/- 2%). The dose of diazoxide and the degree of hyperglycemia were interactive. Profound (blood glucose 574 +/- 23 mg/dl) but not moderate hyperglycemia blocked the effects of high-dose (5.0 mg/kg) diazoxide [26 +/- 3, 15 +/- 3 (P < 0.05), and 11 +/- 2% (P < 0.05), respectively]. There were no differences in systemic hemodynamics, AAR, or coronary collateral blood flow (by radioactive microspheres) between groups. The results indicate that diabetes or hyperglycemia impairs activation of mitochondrial K(ATP) channels.  相似文献   

17.
BACKGROUND: Transferring adolescents with diabetes from pediatric to adult care remains a challenge and the outcome is often unknown. The aims of this study were to determine the patients' perception of transfer arrangements and to analyze health care use and metabolic control. METHODS: A telephone questionnaire was conducted for patients who had been transferred from the pediatric clinic to adult care between 1995 and 2003. Of 161 identified patients, 101 (58 females, 43 males, mean age 22.1 +/- 2.4 years) were interviewed. Pediatric case notes and, if available (n = 44), current notes were analyzed to validate answers from the interview. RESULTS: After transfer, 52.5% of patients changed their health care provider at least once. The mean frequency of changes was 1.47. There was a significant decrease in clinic attendance rate after transition (8.5 +/- 2.3/years vs. 6.7 +/- 3.2/years). Patients criticized the lack of arrangements, poor information about transfer and the specific age for transition (18 years) set by legislation. The transfer was considered a negative experience by 58 patients. The patients assumed their metabolic control (HbA1c) was better than it really was (7.5 +/- 1.3% vs. 8.3 +/- 1.6%, p < 0.05). Actual HbA1c from case notes pre- and post-transfer did not change significantly (8.5 +/- 1.5% vs. 8.4 +/- 1.7%, n = 44, p = 0.441). CONCLUSION: The establishment of transition clinics and closer cooperation between specialists in pediatric and adult medicine is mandatory. Such changes are demanded by patients and would ensure better uptake of health care services after transfer.  相似文献   

18.
We investigated the effect of muscle metaboreflex activation on left circumflex coronary blood flow (CBF) and vascular conductance (CVC) in conscious, chronically instrumented dogs during treadmill exercise ranging from mild to severe workloads. Metaboreflex responses were also observed during mild exercise with constant heart rate (HR) of 225 beats/min and beta(1)-adrenergic receptor blockade to attenuate the substantial reflex increases in cardiac work. The muscle metaboreflex was activated via graded partial occlusion of hindlimb blood flow. During mild exercise, with muscle metaboreflex activation, hindlimb ischemia elicited significant reflex increases in mean arterial pressure (MAP), HR, and cardiac output (CO) (+39.0 +/- 5.2 mmHg, +29.9 +/- 7.7 beats/min, and +2.0 +/- 0.4 l/min, respectively; all changes, P < 0.05). CBF increased from 51.9 +/- 4.3 to 88.5 +/- 6.6 ml/min, (P < 0.05), whereas no significant change in CVC occurred (0.56 +/- 0.06 vs. 0.59 +/- 0.05 ml. min(-1). mmHg(-1); P > 0.05). Similar responses were observed during moderate exercise. In contrast, with metaboreflex activation during severe exercise, no further increases in CO or HR occurred, the increases in MAP and CBF were attenuated, and a significant reduction in CVC was observed (1.00 +/- 0.12 vs. 0.90 +/- 0.13 ml. min(-1). mmHg(-1); P < 0.05). Similarly, when the metaboreflex was activated during mild exercise with the rise in cardiac work lessened (via constant HR and beta(1)-blockade), no increase in CO occurred, the MAP and CBF responses were attenuated (+15.6 +/- 4.5 mmHg, +8.3 +/- 2 ml/min), and CVC significantly decreased from 0.63 +/- 0.11 to 0.53 +/- 0.10 ml. min(-1). mmHg(-1). We conclude that the muscle metaboreflex induced increases in sympathetic nerve activity to the heart functionally vasoconstricts the coronary vasculature.  相似文献   

19.
20.
In a maternity hospital with the decentralized system of infant care the presence of the group B streptococcal colonization of puerperants (13.0 +/- 4.5%), newborn infants (25.0 +/- 4.4%) and medical staff (16.9 +/- 3.2%) was established. The strains isolated in this hospital belonged to 13 different serotypes and antigenic combinations with type 1 a/c dominating among them (28.7 +/- 4.8%). Group B streptococci were found to be transmitted by the vertical way in one out of two colonized mother-child pairs, in all other cases the nosocomial spread of streptococci occurred.  相似文献   

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