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61.
We report two cases of successful pregnancy in women with chronic, infantile onset, or type II spinal muscular atrophy, both of whom delivered healthy, unaffected babies. The patients required concurrent management by a physiatrist, pulmonologist, and perinatologist throughout the pregnancy. Complications included recurrent urinary tract infections, dyspnea and worsening of pulmonary function, wheelchair seating and positioning problems, and musculoskeletal and low back pain. These problems resolved postpartum. One woman had vaginal delivery, the other had caesarean section, both of which were well-tolerated. Because of severe musculoskeletal deformity, pelvic assessment is necessary to determine the mode of delivery. The uterus has normal contractility and effective labor patterns can be established. Spinal/epidural anesthesia may be contraindicated because of spine deformity. The pregnancies had no deleterious effect on the progression of the disease in our patients, both of whom reported a positive experience with great personal fulfillment. 相似文献
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63.
VL Beggs NJ Birkemeyer WC Nugent LJ Dacey GT O'Connor 《Canadian Metallurgical Quarterly》1996,1(4):180-186
BACKGROUND: Early rehospitalization after coronary artery bypass grafting (CABG) is an expensive and frequently adverse outcome. Rehospitalization rates after various surgical procedures have been used as an indicator of quality of care. Determining the extent to which rehospitalization rates reflect patient case mix and severity of illness rather than quality of care requires detailed information regarding the patients, the care they received, and the reasons for their rehospitalization. METHODS: We conducted a nested case control study comparing 110 CABG patients who were rehospitalized within 30 days after discharge with 224 control patients. Control patients were randomly selected from patients undergoing CABG during the same time frame as the cases and were matched on age, gender, and priority of surgery. A detailed chart review provided information regarding treatment in the postsurgical period, in addition to the preoperative information collected on all CABG patients as part of an ongoing regional prospective study. RESULTS: The overall rehospitalization rate was 13.8%. The most common reasons for rehospitalization included: wound infection (19%), atrial fibrillation (13%), pleural effusion (11%), and thromboembolic event (10%). Preoperative severity of illness and comorbidity accounted for 24% of the total variance. After adjustment for these factors, discharge hematocrit less than 30% (OR = 2.01, p = 0.018) and several discharge medications including: antiarrhythmics (OR = 3.26, p = 0.047), diuretics (OR = 2.18, p = 0.055), beta blockers (OR = 0.44, p = 0.036), and long length of stay (more than 7 days; OR = 2.09, p = 0.029) were the most important predictors of rehospitalization risk. CONCLUSIONS: Although the reasons for rehospitalization after CABG are heterogeneous and related to patient severity of illness as well as comorbid status, several of the most common are potentially preventable and related to quality of care. Rehospitalization was not related to early discharge. 相似文献
64.
GT Chung V Sundaresan P Hasleton R Rudd R Taylor PH Rabbitts 《Canadian Metallurgical Quarterly》1996,56(7):1609-1614
Lung tumors, particularly squamous cell carcinomas, are believed to develop through a series of morphological abnormalities, driven by underlying somatic genetic changes. One way of studying this process is to analyze candidate somatic genetic changes in samples of squamous metaplasia and bronchial dysplasia of varying degrees of severity as well as tumor from the same patient. This assumes a clonal relationship between these lesions. In this article, we provide evidence that adjacent, physically distinct bronchial abnormalities are clonally related. This has been achieved using a plaque assay technique to detect the same p53 mutation, present throughout a tumor specimen, in a small proportion of cells in an adjacent squamous metaplasia. In addition, we have obtained two dysplasia samples from a tumor-free patient over a 9-month interval. The earlier sample had one p53 mutation, whereas the later sample has to p53 mutations on different alleles. Thus, the pattern of clonal evolution detected in the parallel samples mimics the pattern seen in longitudinal samples and supports the analysis of synchronously collected samples for the study of tumor progression. 相似文献
65.
BACKGROUND: Because cigarette smoking affects the respiratory system earlier than many other systems of the human body, an attempt was made to identify objective and subjective respiratory problems among adolescent smokers. METHODS: Two studies based on a pulmonary function test (PFT), respiratory symptom assessment, and other smoking-related variables were undertaken. Study 1 involved cigarette smokers (N = 18, 22% males, mean age 18.7 years) from a freshman college class who participated in an acute smoking experiment that involved performing a PFT before and after smoking a single cigarette. Study 2 was performed on a combined group of vocational-technical high school students and freshman college students (N = 44, 48% males, mean age 17.8 years) where PFT parameters, respiratory symptoms, and smoking-related health vulnerability were assessed among smokers vs nonsmokers. RESULTS: In Study 1, the average reduction across PFT parameters was 4.4% and the mean estimated lung age increased from 27.15 to 29.84 years. In Study 2, a consistent trend toward reduction of PFT values among smokers vs nonsmokers was observed; the mean forced expiratory volume in 1 sec/forced vital capacity ratio (90.51% vs 94.59%), peak expiratory flow rate (80.32% vs 92.06%), and flow rate of 50% of forced vital capacity (88.39% vs 102.81%) differed significantly. Significant differences in respiratory symptoms were also observed among smokers vs nonsmokers. CONCLUSIONS: The beginning of respiratory health disorders can be identified among adolescent smokers. These findings might provide important clues on how to improve outcomes from health care provider-based adolescent smoking cessation counseling. 相似文献
66.
KA Gray OS Pogrebinsky GT Mrachko L Xi DJ Monticello CH Squires 《Canadian Metallurgical Quarterly》1996,14(13):1705-1709
The development of biocatalytic desulfurization of petroleum fractions may allow its use in place of conventional hydrodesulfurization (HDS). Dibenzothiophene (DBT) is representative of a broad range of sulfur heterocycles found in petroleum that are recalcitrant to desulfurization via HDS. Rhodococcus sp. strain IGTS8 has the ability to convert DBT to 2-hydroxybiphenyl (HBP) with the release of inorganic sulfur. The conversion of DBT to HBP is catalyzed by a multienzyme pathway consisting of two monooxygenases and a desulfinase. The final reaction catalyzed by the desulfinase appears to be the rate limiting step in the pathway. Each of the enzymes has been purified to homogeneity and their kinetic and physical properties studied. Neither monooxygenase has a tightly bound cofactor and each requires an NADH-FMN oxidoreductase for activity. An NADH-FMN oxidoreductase has been purified from Rhodococcus and is a protein of approximately 25,000 molecular weight with no apparent sequence homology to any other protein in the databases. We describe a unique sulfur acquisition system that Rhodococcus uses to obtain sulfur from very stable heterocyclic molecules. 相似文献
67.
68.
In the present work, the effects of GnRH on the translation (by [14C]leucine incorporation; [14C]Leu-LH) and the glycosylation of LH by rat pituitary cells in primary culture were established. The use of specific markers as radioactive precursors made it possible to discriminate the action of the neurohormone on proximal glycosylation (by[3H]mannose incorporation; [3H]Man-LH) as well as distal glycosylation (by [3H]galactose incorporation; [3H]Gal-LH) in the course of synthesis and release of LH. Pituitary cells from ovariectomized adult rats were incubated for different periods between 0 and 5 h in medium containing [14C]Leu plus [3H]Man or [14C]Leu plus [3H]Gal with or without 10 nM GnRH. GnRH increased synthesis and release of newly synthesized LH. The magnitude of the stimulatory effect on the kinetics of [14C]Leu (slope = 63.58; 158% of control) and [3H]Man (slope = 75.15; 161%) incorporation to LH was similar. The action of the neurohormone appears to be exerted on translation, the increased [3H]Man incorporation being a secondary phenomenon arising from the greater amount of available polypeptide chains as acceptors of the polymannose core. However, a direct effect of GnRH on proximal glycosylation cannot be excluded. GnRH also stimulated the kinetics of release of [14C]Leu-LH (slope = 6.14; 236% of control) and [3H]Man-LH (slope = 8.06; 191%). Comparatively, the effect of GnRH on [3H]Gal-LH was detected earlier than that on LH labeled with the other precursors; increases in rates of production (slope = 71.57; 278% of control) and release (slope = 32.08; 494%) were higher than those in [14C]Leu- and [3H]Man-LH kinetics, indicating that GnRH acts specifically on this distal step of LH glycosylation. GnRH enhanced the relative terminal glycosylation ([3H]Gal/[14C]Leu ratio) of total and release LH without modifying the relative proximal glycosylation ([3H]Man/[14C]Leu ration) of the hormone. We conclude that GnRH can induce not only changes in the quantity (greater number of molecules) but also in the quality (molecules more glycosylated) of the secreted LH by acting directly at translation and distal glycosylation level. 相似文献
69.
Three patients, one healthy and two immunocompromised, developed cutaneous reactions that histologically mimicked granuloma annulare at sites of resolved varicella-zoster virus (VZV) reactivation infections. Variable latency periods between the infection and the granulomatous reaction were noted. As in other case reports, the presence of VZV DNA in these lesions was inconsistently demonstrated by the polymerase chain reaction (PCR) and appears more common in early, as opposed to late, post-zoster granulomas. In addition to various granulomatous reactions, vasculitic and neoplastic eruptions following resolved VZV infections have been described and are reviewed here. Therapeutically, topical, intralesional and systemic corticosteroids, as well as acyclovir, have been tried with inconsistent results. Although the pathogenesis remains unclear, the presence of VZV DNA in early lesions that histologically do not display viral cytopathic changes, suggests the virus induces an atypical delayed hypersensitivity reaction not affected by antiviral therapy. 相似文献
70.
Using a balanced placebo drink administration procedure, 48 undergraduate male social drinkers were presented with erotic and nonerotic stimuli after completing the Mosher Forced-Choice Guilt Scale. Selective attention and recognition memory were measured in both visual and auditory modalities; penile tumescence was recorded continuously in reponse to auditory stimuli. The belief that alcohol had been consumed increased penile tumescence to both heterosexual and homosexual stimuli, but only in Ss high in sex guilt. Mild intoxication itself had no effect. Alcohol impaired memory for visual stimuli, while the belief that alcohol had been drunk facilitated memory for stimuli in the auditory modality. Correlational analysis did not support the hypothesis that alcohol expectation's impact on sexual responsiveness is mediated directly through its influence on selective attention and memory processes. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献