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1.
The renal and hemodynamic effects of dopamine were measured during the immediate postoperative period in six infants following repair of congenital cardiac defects. Dopamine was infused at rates of 5, 10, and 15 micrograms/kg/min. Cardiac index (CI) increased significantly at a dopamine infusion rate of 15 micrograms/kg/min. The glomerular filtration rate (GFR) and urine output increased at dopamine infusion rates of 5 and 10 micrograms/kg/min and returned to baseline at 15 micrograms/kg/min. No significant changes occurred in right atrial pressure (RAP), left atrial pressure (LAP), systemic artery pressure, systemic vascular resistance (SVR), or pulmonary vascular resistance (PVR). Heart rate (HR) increased slightly at a dopamine infusion rate of 15 micrograms/kg/min. Pulmonary artery pressure (PAP) increased significantly in only one patient. These data demonstrate that infants require high doses of dopamine to produce the hemodynamic effects seen in adults and that these higher doses may be used without adverse renal effects.  相似文献   
2.
To determine the value of scintigraphy to detect posttransplantation complications of the allografted pancreas, we retrospectively reviewed 209 scintigrams obtained with 99mTc-sulfur colloid (99mTc-SC) and 99mTc-glucoheptonate (99mTc-GH). The scintigraphic studies were performed in 37 recipients of simultaneous renal and pancreatic allografts harvested from the same donor. 99mTc-SC was used as an indicator of thrombotic vasculitis; pancreatic perfusion and blood-pool parameters were monitored with 99mTc-GH. In 11 of the 37 recipients, scintigraphic abnormalities suggested posttransplantation infarction. Recurrent episodes of acute rejection of the pancreatic allograft, which always coincided with acute rejection of the renal allograft, were monitored in 24 recipients. Rejection-induced ischemic pancreatitis was suggested in 12 of the 24 recipients and persisted in 10 recipients for several weeks after improvement of renal allograft rejection. Pancreatic atrophy was suggested scintigraphically in 16 of the 24 recipients with recurrent episodes of rejection. Spontaneous pancreatic-duct obstruction and obstructive pancreatitis were associated with a scintigraphic pattern similar to that of rejection-induced ischemic pancreatitis. We concluded that the specific radionuclides used in this series are useful for the surveillance and assessment of posttransplantation pancreatic infarction, acute rejection, pancreatitis, and atrophy.  相似文献   
3.
This study investigated whether immunostimulatory DNA sequences (ISS) induce a transient or sustained inhibition of Th2 responses to inhaled antigen. We sensitized mice with subcutaneous injections to develop a Th2 response to ovalbumin (ova) and then administered a dose of ISS prior to ova inhalation challenge. Mice were then rechallenged with ova by inhalation a second time at varying time points after the first ova inhalation (1 to 8 weeks later) to determine whether the ISS dose administered prior to the first ova inhalation protected against a subsequent second ova inhalation challenge. A single dose of ISS inhibited the Th2 response to the first inhalation of ova antigen, as well as 4 weeks later to the second inhalation of ova. However, ISS did not inhibit a Th2 response to the second inhalation of ova 8 weeks later. The reversible inhibition of Th2 responses at 8 weeks suggests the need for repeated ISS administration at monthly intervals.  相似文献   
4.
In vivo microdialysis, behavioral activity assessments, and a conditioned place preference (CPP) test were used to investigate dopaminergic correlates of cocaine-conditioned behaviors. Over 12 days, rats were given either intravenous cocaine (4.2 mg/kg) or saline (6 cocaine and 6 saline infusions) daily in distinctively different environments. The following day, rats were tested in the cocaine- and saline-paired environments; 48 hr later, CPP was determined. The cocaine-associated environment elicited greater nucleus accumbens dopamine (NAcc DA) levels, hyperactivity, and place preference, though the emergence of DA increases was not in synchrony with peak behavioral activation. Although conditioned behavioral effects after repeated cocaine are well documented, direct evidence of increased NAcc DA in response to a cocaine-paired environment has not been previously reported. Discrepancies with previous work are attributed to a number of methodological differences.  相似文献   
5.
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
6.
Cocaine/"crack" dependence among psychiatric inpatients   总被引:1,自引:0,他引:1  
The authors studied 40 cocaine-dependent subjects admitted to psychiatric inpatient wards of a metropolitan hospital because of general psychiatric symptoms. The results indicate that the predominant form of cocaine administration (88%) was freebasing "crack." DSM-III-R cluster B personality disorders (N = 17) and schizophrenia (N = 13) constituted the diagnoses for 75% of the sample. Compared to the schizophrenic patients in this cohort, the patients with cluster B personality disorders used cocaine in greater quantities and more frequently and began abuse of the drug at an earlier age. The escalation in urban areas of psychiatric hospitalizations attributed to use of crack may be largely related to psychiatric symptoms in cocaine-dependent patients with personality disorders as well as cocaine-induced psychopathology in schizophrenic patients.  相似文献   
7.
Endocardial fibroelastosis (EFE) in a mother and daughter are reported. This entity has a primary and secondary form. In this case, the 23-year-old mother died 11 months after delivery with findings of EFE. At age 3(1/2) years, the daughter was admitted in congestive heart failure and did not respond to medical management. The autopsy findings revealed EFE. Endocardial fibroelastosis in both mother and daughter is a very rare finding.  相似文献   
8.
Frequency and yield of postoperative fever evaluation.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE: In women undergoing major gynecologic surgery, we wish to determine the frequency and yield of blood culture, urine culture, and chest X-ray evaluation of postoperative fever. METHODS: A retrospective review of 537 consecutive patients undergoing major gynecologic surgery was performed. In patients who developed postoperative fever, it was determined whether blood culture, urine culture, and/or chest X-ray were performed, and, if so, the frequency of positive results was evaluated. RESULTS: Two hundred eleven patients (39%) developed postoperative fever. Blood cultures were obtained in 77 of 211 (37%) febrile patients, urine cultures in 106 of 211 (50%) febrile patients, and chest X-ray in 54 of 211 (26%) febrile patients. Zero of 77 blood cultures were positive, 11 of 106 (10%) urine cultures were positive, and 5 of 54 (9%) chest X-rays were positive. Logistic regression revealed that late onset fever predicted for positive urine cultures and early onset fever and advanced age predicted for pneumonia. Eighty percent of patients with pneumonia were symptomatic. In 92% of patients with postoperative fever, no infections or pathologic process were diagnosed. CONCLUSION: Although postoperative fever is frequently evaluated by blood culture, urine culture, and chest X-ray, evaluation rarely yields positive results.  相似文献   
9.
Aims   To investigate whether substance use disorders (SUDs) are associated with verbal intellectual ability, psychomotor processing speed, verbal and visual working memory, executive function and verbal learning in young adults, and to study the associations of SUD characteristics with cognitive performance.
Participants   A population-based sample ( n  = 466) of young Finnish adults aged 21–35 years.
Measurements   Diagnostic assessment was based on all available information from a structured psychiatric interview (SCID-I) and in- and out-patient medical records. Established neuropsychological tests were used in the cognitive assessment. Confounding factors included in the analyses were comorbid psychiatric disorders and risk factors for SUDs, representing behavioural and affective factors, parental factors, early initiation of substance use and education-related factors.
Findings   Adjusted for age and gender, life-time DSM-IV SUD was associated with poorer verbal intellectual ability, as measured with the Wechsler Adult Intelligence Scale–Revised (WAIS-R) vocabulary subtest, and slower psychomotor processing, as measured with the WAIS-R digit symbol subtest. Poorer verbal intellectual ability was accounted for by parental and own low basic education, whereas the association with slower psychomotor processing remained after adjustment for SUD risk factors. Poorer verbal intellectual ability was related to substance abuse rather than dependence. Other SUD characteristics were not associated with cognition.
Conclusions   Poorer verbal intellectual ability and less efficient psychomotor processing are associated with life-time alcohol and other substance use disorders in young adulthood. Poorer verbal intellectual ability seems to be related to parental and own low basic education, whereas slower psychomotor processing is associated with SUD independently of risk factors.  相似文献   
10.

Aims

Better understanding risk factors for metabolic syndrome (MetS) will allow early targeted intervention to mitigate long term risk. We aim to determine the disparate impact of each individual MetS component on overall risk of developing MetS, stratified by sex, race/ethnicity, and age.

Methods

Using data from the 2003–2014 National Health and Nutrition Examination Survey (NHANES), MetS prevalence among adults (age ≥18) was stratified by sex, race/ethnicity, age, and by individual MetS components (e.g. hypertension (HTN), diabetes mellitus (DM), waist circumference, serum high density lipoprotein (HDL), serum triglycerides (TG). Mutlivariate logistic regression models were used to evaluate the disparate impact of each risk factor on MetS risk.

Results

Overall MetS prevalence was 33.3%, with the highest prevalence among older individuals, among women, and among Hispanics. When stratified by each individual component of MetS, low serum HDL was the strongest predictor of MetS risk overall and among both men and women, among all race/ethnic groups, and among all age groups (overall: OR 20.1, 95% CI 18.6–21.7). While presence of DM also increased an individual’s risk of MetS, DM was the weakest predictor of MetS.

Conclusions

Among U.S. adults, low serum HDL carries the strongest risk in predicting development of MetS. This effect was seen among men and women, among all race/ethnic groups, and among all age groups, highlighting the importance of low serum HDL as a marker of MetS risk.  相似文献   
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