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84.
Our study explored risk factors and birth outcomes of a community maternal and child outreach program for high poverty mothers in East and Central Harlem. We conducted a retrospective chart review of 75 mother–infant dyads, with singleton pregnancies, receiving antepartum and postpartum home visits. Inexperienced parenting was associated with increased odds of giving birth to an infant weighing <2,700 g compared to experienced parenting after adjustment for race/ethnicity and preeclampsia diagnosis (odds ratio (OR) 4.9, p = 0.04). Mothers had comparatively lower depression risk in the postpartum period compared to antepartum (p = 0.006).  相似文献   
85.
Limiting the widespread use of 24-hr pH monitoring is the necessity of manometrically placing the pH probe 5 cm above the proximal lower esophageal sphincter (LES) border. Therefore, we prospectively compared LES localization by gastroesophageal pH step-up with manometry in 71 patients and 14 asymptomatic volunteers. The gastroesophageal pH step-up significantly correlated with the proximal LES border in patients (r=0.53, P<0.0001) and volunteers (r=0.91, P<0.0001). Based on previously published criteria, the pH step-up value was considered acceptably accurate if it was within ±3 cm (6 cm total span) of the manometrically determined proximal LES border. In 58% of patients and 29% of volunteers the pH step-up occurred outside this accuracy range. Esophagitis (P=0.015) and abnormal reflux parameters (P=0.002) were variables contributing to this error. Subsequent analysis found that the pH step-up overestimated the proximal LES border and occurred at the midportion of the sphincter. The pH step-up still inaccurately located the mid LES in 34% of patients. Therefore, manometry should remain the standard for accurate LES localization prior to placing the pH probe.  相似文献   
86.
In 20 healthy volunteers ingesting 5 to 50 ml of51Cr-red cells, reaction intensities obtained with four chemical methods for fecal occult blood were compared with the “true” blood loss simultaneously determined by radioassay of each stool. Dilute tincture of guaiac reagent was found to have the same sensitivity and high frequency of false-positive reactions as the saturated guaiac reagent, but was more reproducible. HematestTM was slightly less sensitive but was poorly reproducible and yielded frequent false-negative as well as false-positive reactions. False-positive reactions by both methods were not eliminated by a meat-free diet; they were increased with guaiac reagents if stools were stored for 3 or more days. A new guaiac method (HemoccultTM) was found to be one-fourth as sensitive as the older tests, but was virtually free from false-positive reactions, even on an unrestricted diet and after storage of the stool specimens. It is recommended that the use of Hematest be abandoned and that Hemoccult be used preferentially if future studies confirm that its sensitivity is sufficient to detect most gastrointestinal lesions which are yielding occult blood.  相似文献   
87.
We develop the theory of semi-infinite cohomology of graded Lie algebras first introduced by Feigin. We show that the relative semi-infinite cohomology has a structure analogous to that of the de Rham cohomology in Kähler geometry. We prove a vanishing theorem for a special class of modules, and we apply our results to the case of the Virasoro algebra and the Fock module. In this case the zero cohomology is identified as the physical subspace of the Fock module and the no-ghost theorem follows. We reveal the profound relation of semi-infinite cohomology theory to the gauge-invariant free string theory constructed by Banks and Peskin. We then indicate the connection between gauge-invariant interacting string theories and the geometric realizations of the infinite-dimensional Lie algebras.  相似文献   
88.
STUDY OBJECTIVES: This study examines long-term trends in incidence rates of hospitalized pulmonary sarcoidosis in a large cohort of Navy personnel, and evaluates the possible relationship of sarcoidosis with occupation. DESIGN: Incidence rates of first hospitalizations were determined for black and white male Navy enlisted personnel on active duty from 1975 to 2001. SETTING: Navy service includes a potential for exposure to a variety of substances, including nonskid coatings used on ship decks that may be aerosolized during removal. Particulate matter containing aluminum, titanium, and silicates has been identified in nonskid samples. Specific occupational groups may have had greater exposure potential than others. PATIENTS OR PARTICIPANTS: Hospitalized cases included sarcoidosis (n = 674), asthma (n = 3,536), emphysema and chronic bronchitis (n = 1,103), respiratory conditions due to fumes and vapors (n = 61), and pneumoconiosis (n = 51) observed in 9,953,607 person-years of active-duty service. INTERVENTIONS: None. However, improvements were made in personal protective gear and other countermeasures to prevent or limit respiratory exposures during service. MEASUREMENTS AND RESULTS: Annual overall hospitalized sarcoidosis incidence rates per 100,000 were 24.9 for black men and 3.5 for white men (black/white ratio of 7.1, p < 0.0001). Annual incidence rates in blacks declined markedly, particularly since 1989, but the black/white ratio remained high through 1999. Occupational associations were present in blacks and whites. Black ship's servicemen (23 cases) and aviation structural mechanics specializing in structures (12 cases) had more than twice the expected incidence rate compared to all blacks, and white mess management specialists (15 cases) had twice the overall white incidence rate. CONCLUSIONS: There was a steep decline in incidence of hospitalized sarcoidosis in blacks in the Navy. Occupational associations suggest the possibility that a dust or moisture-related lung disease may have been erroneously classified as sarcoidosis, or, alternatively, that sarcoidosis had a previously unrecognized occupational component.  相似文献   
89.

Aim

The aim of the present study was to determine (1) whether successful intraoperative electromyography monitoring for lateral spread response (LSR) is possible with partial neuromuscular blockade (NMB) in subjects undergoing microvascular decompression (MVD) for hemifacial spasm and (2) the adequate level of NMB to achieve that goal.

Material and methods

A total of 61 patients in whom LSR was monitored during MVD were enrolled in the study. Patients were randomly allocated to two groups: group TOF in which the NMB target was maintenance of two train-of-four (TOF) counts and group T1 in which the NMB target was maintenance of a T1/Tc ratio of 50?% (T1: first twitch height of TOF and Tc: control twitch height). The adductor pollicis brevis muscle was used to monitor TOF responses. The frequency of successful LSR monitoring, defined as successful baseline establishment and maintenance of LSR until surgical decompression, was compared between the two groups.

Results

Of the 61 patients 2 were excluded from the study so that 30 patients in group TOF and 29 patients in group T1 were analyzed. The success rate of LSR monitoring was clinically acceptable and significantly higher in group T1 than in group TOF, i.e. n?=?15 (50.0?%) in group TOF versus n?=?24 (82.8?%) in group T1 (P?=?0.008), corresponding to a 32.8?% higher success rate in group T1 than group TOF (95?% CI: 13.9–51.7?%). Mean vecuronium infusion dose was smaller and mean TOF count was higher in group T1 than group TOF with a TOF count =?2 (1) in group TOF versus 3 (1) in group T1 (P?=?0.003). Mean sevoflurane and remifentanil infusion doses were not different between groups. There was no incidence of spontaneous movement during microscopy in either group.

Conclusion

Maintenance of partial NMB with a target T1/Tc ratio of 50?% resulted in a clinically acceptable success rate of LSR monitoring and surgical condition during MVD. Maintenance of partial NMB with a target T1/Tc ratio of 50?% rather than TOF count of two during LSR monitoring for MVD can therefore be recommended.  相似文献   
90.
Objectives. Increasing 25-hydroxyvitamin D serum levels can prevent a wide range of diseases. There is a concern about increasing kidney stone risk with vitamin D supplementation. We used GrassrootsHealth data to examine the relationship between vitamin D status and kidney stone incidence.Methods. The study included 2012 participants followed prospectively for a median of 19 months. Thirteen individuals self-reported kidney stones during the study period. Multivariate logistic regression was applied to assess the association between vitamin D status and kidney stones.Results. We found no statistically significant association between serum 25-hydroxyvitamin D and kidney stones (P = .42). Body mass index was significantly associated with kidney stone risk (odds ratio = 3.5; 95% confidence interval = 1.1, 11.3).Conclusions. We concluded that a serum 25-hydroxyvitamin D level of 20 to 100 nanograms per milliliter has no significant association with kidney stone incidence.An issue of possible concern related to the use of vitamin D supplementation is a reported increase in risk of kidney stones.1 Mounting evidence indicates that a 25-hydroxyvitamin D (25[OH]D) serum level in the range of 40 to 60 nanograms per milliliter (ng/mL) is needed for substantial reduction in risk of a wide range of diseases including breast cancer,2 colorectal cancer,3 multiple sclerosis,4 and type 1 diabetes.5,6 However, few people can achieve 25(OH)D in the range higher than 40 ng/mL without supplementation.7GrassrootsHealth is a nonprofit public health research organization that runs a large population cohort study of participants who reach and sustain, if desired, a 25(OH)D serum level of their choice and tracking subsequent health outcomes. GrassrootsHealth has assembled a database that includes information on serum 25(OH)D concentrations, demographic characteristics, and health status measures. These data include values from 5552 individuals with daily supplemental intakes averaging 3600 international units (IU) per day and an average 25(OH)D level of 45 ng/mL, which is higher than the ranges found in most other cohorts.2,4In this study we investigated whether serum 25(OH)D concentration in the range of 20 to 100 ng/mL was associated with incidence of kidney stones in all participants who provided data at 2 or more sampling times.  相似文献   
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