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151.
152.
TL Trus T Bax WS Richardson GD Branum SJ Mauren LL Swanstrom JG Hunter 《Canadian Metallurgical Quarterly》1997,1(3):221-7; discussion 228
The complications of laparoscopic paraesophageal hernia repair at two institutions were reviewed to determine the rate and type of complications. A total of 76 patients underwent laparoscopic paraesophageal hernia repair between December 1992 and April 1996. Seventy-one of them had fundoplication (6 required a Collis-Nissen procedure). Five patients underwent hernia reduction and gastropexy only. There was one conversion to laparotomy. Traumatic visceral injury occurred in eight patients (11%) (gastric lacerations in 3, esophageal lacerations in 2, and bougie dilator perforations in 3). All lacerations were repaired intraoperatively except for one that was not recognized until postoperative day 2. Vagus nerve injuries occurred in at least three patients. Three delayed perforations occurred in the postoperative period (4%) (2 gastric and 1 esophageal). Two patients had pulmonary complications, two had gastroparesis, and one had fever of unknown origin. Seven patients required reoperation for gastroparesis (n = 2), dysphagia after mesh hiatal closure of the hiatus (n = 1), or recurrent herniation (n = 4). There were two deaths (3%): one from septic complications and one from myocardial infarction. Paraesophageal hernia repair took significantly longer (3.7 hours) than standard fundoplication (2.5 hours) in a concurrent series (P <0.05). Laparoscopic paraesophageal hernia repair is feasible but challenging. The overall complication rate, although significant, is lower than that for nonsurgically managed paraesophageal hernia. 相似文献
153.
The antimalarial drug mefloquine binds avidly to phospholipids in biomembranes. The thermodynamics of the partitioning process in dimyristoylphosphatidylcholine (DMPC) bilayers was investigated to give some insight into the drug-phospholipid interaction. Thermodynamic parameters for the partition equilibria were evaluated from the equilibrium partition coefficients measured as a function of temperature. Negative values of delta H and delta S were obtained for the transfer of mefloquine from the aqueous to the gel phase of the phospholipid. The partitioning is enthalpy controlled which suggests that mefloquine interacts strongly with the phospholipid phase. In contrast, the partitioning of mefloquine into the liquid crystalline phase of DMPC is entropy controlled which is typical of a hydrophobic interaction between mefloquine and the aqueous phase. The partitioning of mefloquine into the bulk solvents octanol and hexane were found to be enthalpy and entropy controlled, respectively. The enthalpy dominated partitioning of mefloquine into gel phase DMPC and octanol is attributed to the occurrence of hydrogen bonding and van der Waals interactions between solute and solvent. The flat shape of mefloquine may further aid its interaction with the orderly domains of the lipidic/organic phase. This is apparent from a comparison of the partitioning characteristics of another structurally related but conformationally different molecule, quinine into DMPC and octanol. 相似文献
154.
DJ Kesler TS Dyson RN Summers TL Steckler TG Nash 《Canadian Metallurgical Quarterly》1997,47(4):281-289
Despite the presence of several human disease genes on chromosome 11q13, few of them have been molecularly cloned. Here, we report the construction of a contig map encompassing 11q13.1-q13.3 using bacteriophage P1 (P1), bacterial artificial chromosome (BAC), and P1-derived artificial chromosome (PAC). The contig map comprises 32 P1 clones, 27 BAC clones, 6 PAC clones, and 1 YAC clone and spans a 3-Mb region from D11S480 to D11S913. The map encompasses all the candidate loci of Bardet-Biedle syndrome type I (BBS1) and spinocerebellar ataxia type 5 (SCA5), one-third of the distal region for hereditary paraganglioma 2 (PGL2), and one-third of the central region for insulin-dependent diabetes mellitus 4 (IDDM4). In the process of map construction, 61 new sequence-tagged site (STS) markers were developed from the Not I linking clones and the termini of clone inserts. We have also mapped 30 ESTs on this map. This contig map will facilitate the isolation of polymorphic markers for a more refined analysis of the disease gene region and identification of candidate genes by direct cDNA selection, as well as prediction of gene function from sequence information of these bacterial clones. 相似文献
155.
The ability to map interior optical properties of a highly scattering medium from exterior measurements of light propagation is afforded by optical tomography. In this communication, we describe the problem of optical tomography, the techniques of photon migration measurements necessary to accomplish it, and the development of multipixel measurements for rapid collection of optical signals. These multipixel measurements are shown to provide detection of contrast owing to the optical properties of absorption and fluorescence associated with dye-laden heterogeneities embedded in a tissue-like scattering medium. From these rapid measurements, successful reconstruction of an interior optical property map may now be possible with clinically realistic data acquisition times. Applications for the technology arise for biomedical optical imaging for the in vivo detection of disease and the diagnosis of tissue (bio-) chemistry. 相似文献
156.
KA Graham AS Lalani JL Macen TL Ness M Barry LY Liu A Lucas I Clark-Lewis RW Moyer G McFadden 《Canadian Metallurgical Quarterly》1997,229(1):12-24
This article presents the development of a new 82-item rating scale of therapist adherence and competence for supportive-expressive (SE) dynamic psychotherapy for the treatment of cocaine dependence. Sixty-four items are rated for adherence, appropriateness, and quality of prescribed interventions. As part of the pilot/training phase of the National Institute on Drug Abuse Collaborative Cocaine Treatment Study, two independent expert judges rated 32 audiotapes of SE therapy sessions with cocaine-dependent patients, 10 tapes of cognitive therapy (CT) sessions, and 10 tapes of individual drug counseling (IDC) sessions. Reliability was acceptable for adherence but poor for quality and appropriateness. SE therapists used more expressive (interpretative) techniques than did either CT therapists or IDC counselors, and they used more supportive techniques than did IDC counselors. 相似文献
157.
AL Heroux P Silverman MR Costanzo EJ O'Sullivan MR Johnson Y Liao TL McKiernan JE Balhan FS Leya GM Mullen 《Canadian Metallurgical Quarterly》1994,89(1):272-277
BACKGROUND: The diffuse nature of cardiac allograft vasculopathy makes early detection of the disease by traditional noninvasive methods or coronary angiography difficult. The aim of this study was to determine if there is a relation between abnormalities in vessel wall morphology, as assessed by intracoronary ultrasound, and a decreased vasodilatory response to the endothelium-dependent vasodilator papaverine hydrochloride and if cardiac allograft vasculopathy detected by coronary angiography is associated with specific intracoronary ultrasound findings. METHODS AND RESULTS: Twenty-three heart transplant recipients underwent 25 intracoronary ultrasound studies and 24 studies of coronary vasomotor tone 10 days to 8.3 years after surgery using a 20-mHz intracoronary ultrasound catheter. The studies were divided in two groups according to the presence (n = 7, group 1) or absence (n = 18, group 2) of angiographically evident cardiac allograft vasculopathy. Qualitative assessment of vessel wall morphology and quantitative analysis of the vasodilator response to the injection of papaverine hydrochloride into the coronary artery distal to the imaging site were performed off-line, and results for the two study groups were compared. A significantly higher percentage of patients with than without angiographic evidence of cardiac allograft vasculopathy had a three-interface vessel wall morphology by intracoronary ultrasound (100% versus 11%, P < .001). In two recipients who underwent two serial studies, the appearance of three interfaces in the vessel wall or a progressive thickening of the inner interface of the vessel wall occurred in conjunction with the appearance of angiographic cardiac allograft vasculopathy. The vasodilator response to papaverine was less in patients with than in those without angiographically evident cardiac allograft vasculopathy both in terms of absolute and relative increases in lumen diameter (+0.1 +/- 0.12 mm versus +0.3 +/- 0.17 mm, P < .05, and +5.1 +/- 5.3% versus +8.2 +/- 5.3%, P = NS) and lumen cross-sectional area (+0.5 +/- 0.6 mm2 versus +1.7 +/- 1.1 mm2, P < .02, and +7.1 +/- 8.8% versus 16.6 +/- 11.0%, P = .055), respectively. CONCLUSIONS: Intracoronary ultrasound assessment of vessel wall morphology and evaluation of vascular response to endothelium-dependent vasodilators are useful techniques for detecting cardiac allograft vasculopathy. 相似文献
158.
TL Toth SG Baka LL Veeck HW Jones S Muasher SE Lanzendorf 《Canadian Metallurgical Quarterly》1994,61(5):891-894
OBJECTIVE: To determine the potential for in vitro maturation, fertilization, and cleavage after cryopreservation of immature, prophase I human oocytes. DESIGN: Immature oocytes obtained in excess of the number required by the patient were randomized and cryopreserved at the prophase I stage or cultured as control. After thawing and maturation in vitro, test and control oocytes were inseminated with husband's sperm and evaluated for fertilization and cleavage in vitro. SETTING: In vitro fertilization program. PATIENTS: Consenting patients undergoing controlled ovarian hyperstimulation for the purposes of IVF. MAIN OUTCOME MEASURES: Rates of maturation to metaphase II, fertilization, and cleavage were compared between control and cryopreserved oocytes. RESULTS: Upon thaw, 58.5% (72/123) of prophase I oocytes were viable. Control oocytes demonstrated a 74.8% (98/131) maturation rate to metaphase II, a 56.5% (52/92) fertilization rate, and an 11.5% (6/52) blastocyst rate. Cryopreserved oocytes showed a 83.3% (60/72) rate of maturation, a 57.7% (30/52) fertilization rate, and a 3.3% (1/30) blastocyst rate. No significant differences were noted between any of these parameters. CONCLUSIONS: These results demonstrate that prophase I oocytes from stimulated IVF cycles are able to survive cryopreservation and resume meiosis to achieve full nuclear maturation post-thaw. In addition, cryopreserved oocytes retain the same capacity for fertilization and development as control oocytes. 相似文献
159.
Bulimia nervosa is characterized by binge eating and inappropriate compensatory behaviors, such as vomiting, fasting, excessive exercise and the misuse of diuretics, laxatives or enemas. Although the etiology of this disorder is unknown, genetic and neurochemical factors have been implicated. Bulimia nervosa is 10 times more common in females than in males and affects up to 3 percent of young women. The condition usually becomes symptomatic between the ages of 13 and 20 years, and it has a chronic, sometimes episodic course. The long-term outcome has not been clarified. Other psychiatric conditions, including substance abuse, are frequently associated with bulimia nervosa and may compromise its diagnosis and treatment. Serious medical complications of bulimia nervosa are uncommon, but patients may suffer from dental erosion, swollen salivary glands, oral and hand trauma, gastrointestinal irritation and electrolyte imbalances (especially of potassium, calcium, sodium and hydrogen chloride). Treatment strategies are based on medication, psychotherapy or a combination of these modalities. 相似文献
160.
FH Zwieg TL Karfonta LJ Jeske CR Kollauf SK White RE Drazewski J Leske 《Canadian Metallurgical Quarterly》1998,13(1):16-22, 33
Technologically advanced telemetry systems have begun to produce alternatives to the need for continuous visual observation of the electrocardiogram (ECG). Few studies have been conducted to determine the efficacy of these systems in the clinical setting. The purpose of this study was to describe two different approaches to communication of arrhythmia events and corresponding nurse response. One approach, on a cardiac medical unit, utilized a monitoring technician to continuously observe ECGs at a central monitoring technician station (MTS) and notify the nurse of changes. The other approach, on a general medical unit, eliminated the use of the monitoring technician and utilized a pocket paging system (PPS). The PPS interfaced with the computerized arrhythmia detection system from the ECG monitor, which directly alerted the nurse to arrhythmia events. A quasi-experimental comparative post-test design was used. The sample consisted of 50 randomly selected, 2-hour observation periods on each unit during a 3-month period. Data collectors recorded the interaction of the monitoring technician with the arrhythmia detection system and the nurse on the MTS unit, or the nurse using the PPS. Results of this study revealed all arrhythmia events activated an alarm by the computerized arrhythmia detection system. Length of time to notify the nurse was within 0 to 1 minute for both systems. This study demonstrated that the PPS is a viable approach to arrhythmia detection and communication in the medical/cardiac patient population. 相似文献