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991.
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   
992.
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   
993.
994.
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   
995.
Four studies examined how the characteristics of others affect people's self-appraisals. Ss viewed photographs of physically attractive or unattractive targets, then rated their own attractiveness. Study 1 found evidence for a contrast effect: Ss' self-appraisals were more favorable after viewing an unattractive same-sex target than after viewing an attractive same-sex target. Study 2 manipulated psychological closeness by varying the degree to which the S and the target shared similar attitudes and values. Although contrast effects occurred when the S and the target were dissimilar, the reverse tended to be true when the S and the target were related by virtue of their perceived similarity. Two additional studies extended these results, using a different operational definition of psychological closeness. Findings indicate that psychological closeness determines how other people's characteristics affect the self-concept. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
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   
997.
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   
998.
Matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI/FTMS), operating in the negative ion mode, is used to directly observe sugar alcohol borate complexes in a number of plant fractions. The method involves virtually no sample workup and, in the case of celery phloem sap, requires only 40 nL of sap to observe the borate complex. The isolation and characterization of such soluble borate complexes is important in understanding the distribution of boron in plants. The results show that the complexes are composed of two mannitol or sorbitol ligands (L) complexed to a single borate center (B). In some cases, the boron is complexed to non-alditol monosaccharides. Sustained off-resonance collision irradiation dissociation of the BL2- complex, where L is a mannitol, gives fragments that confirm the proposed structure. Complexes of larger oligosaccharides have also been successfully observed using MALDI/FTMS. Semiempirical molecular orbital calculations (AM1) of the mannitol BL2- complex show that the most favorable configuration is with carbons 3 and 4 of both mannitol residues complexed to the borate. This allows maximum interaction of the remaining hydroxyls with the borate center.  相似文献   
999.
This article comments on M. J. Layman and J. R. McNamara's (see record 84-33293) work on remediation for ethics violations, with a focus on psychotherapists' sexual contact with clients. The author argues for a rehabilitation model focused not only on the offending professional but also on the need for amends to the victim, other clients, families, colleagues, and society at large. Regulatory boards must respond responsibly to the long-term, widespread negative consequences of misconduct. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
In the aftermath of recent corporate scandals, managers and researchers have turned their attention to questions of ethics management. We identify five common myths about business ethics and provide responses that are grounded in theory, research, and business examples. Although the scientific study of business ethics is relatively new, theory and research exist that can guide executives who are trying to better manage their employees' and their own ethical behavior. We recommend that ethical conduct be managed proactively via explicit ethical leadership and conscious management of the organization's ethical culture.  相似文献   
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