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41.
The use of nonpulsatile flow during extracorporeal circulation remains popular despite theoretical advantages of pulsatile cardiopulmonary bypass (CPB). Pulsatile CPB is considered to be more physiological than nonpulsatile flow as the pulsatile energy ensures the patency of the vascular bed and mechanical motion of tissue fluid around the cell membrane, improves microcirculation and enhances diffusion. The purpose of this study was to compare the effect of pulsatile and nonpulsatile flow on the coagulation profile, liver and kidney function and also on the haemodynamics in patients undergoing coronary artery bypass grafting on CPB. One hundred patients between 35 and 65 years of age with normal left ventricular function were randomly divided into two equal groups: Pulsatile (P) and nonpulsatile (NP). Haematological parameters, clotting profile, renal parameters, hepatic function tests and haemodynamic variables were measured preoperatively and postoperatively at specific intervals. Surgical, anaesthetic and CPB regimen was standard in all cases. There was a decrease in platelet count during and after CPB in both groups. Coagulation profile and renal function parameters remained similar in both groups except that creatinine clearance was better in group P on the first postoperative day. Urine output was also better in group P. There was no change in liver function tests in both groups. The haemodynamic variables were comparable in both groups. The systemic vascular resistance was higher in group NP postoperatively and oxygen consumption was higher in group P post CPB. In conclusion we did not find any significant difference between pulsatile and nonpulsatile flow during CPB except the creatinine clearance and urine output were better in pulsatile group.  相似文献   
42.
INTRODUCTION: The effect of pelvic radiotherapy on anorectal function is not clearly documented and is investigated in this prospective study. METHODS: Thirty-one males (median age, 70 years) with carcinoma of the prostate (n = 28) and bladder (n = 3) completed proctitis/incontinence symptom score questionnaires and anorectal physiology studies before and six weeks after pelvic radiotherapy. At six months after completion of radiotherapy, 25 of these patients were studied again. The results were expressed as medians and ranges and compared by the Mann-Whitney U test (2-tailed). RESULTS: Six weeks and six months after treatment, respectively, the proctitis symptom scores (0 (0-4) vs. 2 (0-7) (P < 0.001) vs. 2 (0-5) (P < 0.001)) and the incontinence symptom scores (0 (0-5) vs. 4 (0-11) (P < 0.001) vs. 3 (0-14) (P < 0.001)) increased. Urgency, frequency of defecation, anorectal pain, incontinence to liquid stool and to flatus, and alteration in lifestyle were significant symptoms after treatment. The following measurements decreased: anal canal resting pressure (83 (35-137) vs. 79 (26-152) (P = NS) vs. 71 (29-97) (P < 0.01) cm H2O), the squeeze increment (152 (51-135) vs. 162 (63-321) (P = NS) vs. 108 (45-296) (P < 0.042) cm H2O), and the maximum tolerated rectal volume (245 (115-450) vs. 194 (112-344) (P < 0.05) vs. 200 (109-350) (P < 0.138) ml). The rectal electrosensory threshold increased (20 (5.4-44) vs. 22 (9-50.5) (P < 0.134) vs. 31.5 (13.6-76) (P < 0.001) mA). CONCLUSIONS: Anorectal symptoms at six weeks after pelvic radiotherapy are related to reduced rectal capacity and compounded at six months by diminished internal and external sphincter function and rectal mucosal sensitivity.  相似文献   
43.
OBJECTIVE: To describe our experience of post-transplant infections in allogeneic stem cell transplants at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan. METHODS: From July 2001 to September 2006, patients with malignant and non-malignant hematological disorders having human leukocyte antigen (HLA)-matched sibling donors were selected for transplant. Pre-transplant infection surveillance was carried out, and strict prophylaxis against infection was observed. After admission to the hospital, patients were kept in protective isolation rooms, equipped with a HEPA filter positive-pressure laminar airflow ventilation system. Bone marrow and/or peripheral blood stem cells were used as the stem cell source. Cyclosporin and prednisolone were used as prophylaxis against graft-versus-host disease (GVHD). The engraftment was monitored with cytogenetic/molecular analysis and change of blood group. Survival was calculated from the date of transplant to death or last follow-up. RESULTS: One hundred and fifty-four patients received allogeneic stem cell transplants from HLA-matched siblings for various hematological disorders at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan between July 2001 and September 2006. Indications for transplant included aplastic anemia (n=66), beta-thalassemia major (n=40), chronic myeloid leukemia (n=33), acute leukemia (n=8), and miscellaneous disorders (n=7). One hundred and twenty patients were male and 34 were female. The median age of the patient cohort was 14 years (range 1 1/4-54 years). One hundred and thirty-six patients and 135 donors were cytomegalovirus (CMV) IgG-positive. One hundred and forty patients (90.9%) developed febrile episodes in different phases of post-transplant recovery. Infective organisms were isolated in 150 microbiological culture specimens out of 651 specimens from different sites of infections (23.0% culture positivity). Post-transplant infections were confirmed in 120 patients (77.9%) on the basis of clinical assessment and microbiological, virological, and histopathological examination. Mortality related to infections was 13.0%. Fatal infections included CMV disease (100% mortality, 6/6), disseminated aspergillosis (66.7% mortality, 4/6), pseudomonas septicemia (42.9% mortality, 9/21), and tuberculosis (25% mortality, 1/4). CONCLUSIONS: More than 90% of our patients developed febrile episodes with relatively low culture yield. The majority of infections were treated effectively, however CMV, aspergillosis, and pseudomonas infections remained problematic with high mortality.  相似文献   
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While there is evidence of morbidity compression in many countries, temporal patterns of non-communicable diseases (NCDs) in developing countries, such as India, are less clear. Age at onset of disease offers insights to understanding epidemiologic trends and is a key input for public health programs. Changes in age at onset and duration of major NCDs were estimated for 2004 (n = 38,044) and 2018 (n = 43,239) using health surveys from the India National Sample Survey (NSS). Survival regression models were used to compare trends by sociodemographic characteristics. Comparing 2004 to 2018, there were reductions in age at onset and increases in duration for overall and cause-specific NCDs. Median age at onset decreased for NCDs overall (57 to 53 years) and for diabetes, hypertension, heart disease, asthma, mental diseases, eye disease, and bone disease in the range of 2–7 years and increased for cancer, neurological disorders, some genitourinary disorders, and injuries/accidents in the range of 2–14 years. Hazards of NCDs were higher among females for cancers (HR 1.51, 95% CI 1.19–1.90) and neurological disorders (HR 1.18, 95% CI 1.06–1.32) but lower for heart diseases (HR 0.88, 95% CI 0.79–0.97) and injuries/accidents (HR 0.87, 95% CI 0.77–0.99). Hazards were greater among those with lower educational attainment at younger ages and higher educational attainment later in life. Unlike many countries, chronic disease morbidity may be expanding in India for many chronic diseases, indicating excess strain on the health system. Public health programs should focus on early diagnosis and prevention of NCDs.

  相似文献   
47.
The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.

The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2).  相似文献   
48.

Context

The number of patients discharged from acute care hospitals to skilled nursing facilities (SNFs) is rising. These patients have increasingly complex needs and many experience poor outcomes while under SNF care, including hospital readmissions. Patients' goals of care (GoC) are viewed as a factor contributing to unplanned hospital readmissions from SNFs. However, clinicians' perspectives of GoC for hospitalized patients discharged to SNFs are not well-described.

Objectives

To explore how clinicians view GoC for hospitalized patients discharged to SNFs.

Methods

Qualitative study using semi-structured interviews and thematic analysis.

Results

Forty-one clinicians from one acute care hospital and two SNFs completed interviews ranging in length from 14 to 52 minutes (mean = 32 minutes). Of the sample, 22% were nurses, 20% physicians, 15% were from care management, and 15% were from social services. Respondents viewed patients' GoC for continuing treatment at the SNF as important, but acknowledged that they were infrequently discussed during hospitalization. Many respondents felt that patients and families had unrealistic GoC for SNF care. Factors that contributed to unrealistic GoC included patients' limited knowledge of disease processes, prognosis, and treatment options; and inconsistent or insufficient communication of GoC among hospital and SNF clinicians, the patient, and family members. Respondents associated a lack of GoC or unrealistic GoC with patients' dissatisfaction with SNF care, unplanned transitions to hospice, and hospital readmissions.

Conclusions

Respondents reported that GoC conversations infrequently occurred during hospitalization, contributing to unrealistic patient and family expectations for SNF care and poor patient outcomes. Interventions are needed that facilitate timely, accurate, and consistent GoC discussions across care continuums.  相似文献   
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Purpose:

The purpose was to study choroidal thickness and its profile based on location in healthy Indian children using enhanced depth spectral-domain-optical coherence tomography (SD-OCT).

Methods:

In this cross-sectional observational study 255 eyes of 136 children with no retinal or choroidal disease were consecutively scanned using enhanced depth SD-OCT. Eyes with any ocular disease or axial length (AXL) >25 mm or < 20 mm were excluded. A single observer measured choroidal thickness from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500-microns intervals up to 2500 microns temporal and nasal to the fovea. Generalized estimating equations were used to evaluate the correlation between choroidal thickness at various locations and age, AXL, gender and spherical equivalent (SEq).

Results:

Mean age of the subjects was 11.9 ± 3.4 years (range: 5–18 years). There were 62 Females and 74 males. The mean AXL was 23.55 ± 0.74 mm. Mean subfoveal choroidal thickness was 312.1 ± 45.40 μm. Choroid was found to be thickest subfoveally, then temporally. Age, AXL and SEq showed a significant correlation with choroidal thickness, whereas gender did not affect choroidal thickness.

Conclusion:

Our study provides a valid normative database of choroidal thickness in healthy Indian children. This database could be useful for further studies evaluating choroidal changes in various chorioretinal disorders. Age and AXL are critical factors, which negatively correlated with choroidal thickness.  相似文献   
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