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51.
Laparoscopic techniques currently constitute an alternative proposed for the repair of hernias of the inguinofemoral region. Nerve injuries have led some teams to recommend technical principles based on the anatomical relations of these nerves with the subperitoneal fascia transversalis and inguinal fossae. An anatomical study consisting of dissection of nonembalmed cadavres, allowed, after evisceration, dissection of the lumbar plexus and its terminal branches, particularly those supplying the inguinofemoral region: iliohypogastric and ilio-inguinal nerves, the genitofemoral nerve, the femoral nerve and the lateral cutaneous nerve of the thigh. Via transperitoneal laparoscopy, the posterior surface of the anterior abdominal wall is centered on the deep inguinal ring, containing testicular vessels and the vas deferens. This deep inguinal ring receives the genitofemoral nerve. Medially, the anterior parietal peritoneum describes three folds formed by the outline of the epigastric artery, umbilical artery and urachus on the midline. The outline of Hesselbach's ligament separates the deep inguinal ring from Hesselbach's triangle, the zone of weakness of direct inguinal hernia. The iliac psoas muscle pass laterally underneath the inguinal ligament, while the external iliac vessels, subsequently becoming the femoral vessels, are located medially. Pectineal ligament lies on the posterior surface of the femoral ring between the umbilical artery and the epigastric artery. Installation of an abdominal wall prosthesis, either transperitoneally or retroperitoneally, must be centered on the deep inguinal ring, and its solid sutures are located medially to the pectineal ligament and anterior abdominal wall. On the other hand, the nerves at risk of being damaged are situated laterally: the ilio-inguinal and ilio-hypogastric nerves in the plane between external oblique and internal oblique above the anterior superior iliac spine, lateral cutaneous nerve of the thigh under the inguinal ligament close to the anterior superior iliac spine, genitofemoral nerve with the spermatic cord in the deep inguinal ring and femoral nerve underneath the inguinal ligament with the psoas muscle lateral to the external iliac artery. No stapling must be performed under the plane of the inguinal ligament to avoid damage to the femoral vessels and lateral to the deep inguinal ring to avoid nerve damage.  相似文献   
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A Saccharomyces cerevisiae gene (1722 bp), encoding a protein (574 aa) highly homologous to the basic-amino-acid permeases LYP1 and CAN1, was sequenced. The gene, which was named APL1 (Amino-acid Permase Like), is located 881 bp upstream from LYP1 (lysine-specific permease), and in head-to-head orientation to it. These sequence data have been deposited in the EMBL/GenBank/DDBJ nucleotide sequence data libraries under Accession Number X74069.  相似文献   
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55.
Nitrates are useful drugs in cardiovascular medicine. They have a presumed vasovagal effect, which is a rare but often under-recognised complication that is partly caused by central inhibition of the sympathetic nervous system. However, no consistent variable associated with the presumed vasovagal effects following nitrate administration can be identified, and there are only limited reports of the phenomenon in the literature. In fact, the true prevalence of such a complication is unknown, because no data from observational studies exist, although it would seem likely to be a rare event. A greater awareness and recognition of this unusual effect of nitrate use is necessary in view of the increasing use of nitrates. Fortunately, recovery is generally the rule with supportive management.  相似文献   
56.
The uracil permease gene of Schizosaccharomyces pombe was cloned and sequenced. The deduced protein sequence shares strong similarities with five open reading frames from Saccharomyces cerevisiae, namely the uracil permease encoded by the FUR4 gene, the allantoin permease encoded by DAL4, a putative uridine permease (YBL042C) and two unknown ORFs YOR071c and YLR237w. A topological model retaining ten transmembrane helices, based on predictions and on experimental data established for the uracil permease of S. cerevisiae by Galan and coworkers (1996), is discussed for the four closest proteins of this family of transporters. The sequence of the uracil permease gene of S. pombe has been deposited in the EMBL data bank under Accession Number X98696.  相似文献   
57.
A spatial decision aid: A multicriterion evaluation approach   总被引:1,自引:0,他引:1  
There is a growing consensus on the necessity of transforming GIS into real decision support tools and several authors have pleaded for the elaboration of Spatial Decision Support Systems (SDSS). In this paper, we recommend the integration of GIS and Multicriteria Analysis methods. We present the reasons that have led to this integration and a conceptual framework to facilitate it. A prototype will also be presented to show what such a SDSS could be.  相似文献   
58.
The blood–brain barrier (BBB) limits the access of drugs to the brain. Intensive research is being conducted on the development of nanoparticulate drug carriers that mediate transfer across the BBB. A question that has been neglected so far is the potential accumulation of the carrier in the brain upon long‐term exposure. Here, we address this question by implementing a kinetic model to relate drug loading, required concentration of drug in the brain, and drug clearance to the degradation half‐life of the carrier. As a test case with clinical relevance we chose poly‐lactic‐co‐glycolic‐acid (PLGA) as a carrier material and a chemotherapeutic for which the required parameters could be recovered from the literature. For methotrexate with a drug load of 8.5 %, a required concentration of free drug of 1 μm , a release from PLGA of 6 hours, a drug clearance from the brain of 3 hours and a half‐life of polymer degradation of 28 days, a steady‐state accumulation of 1.3 g polymer would be reached in the brain (1.5 L) after seven months. While this number is surprisingly small, further physiological research is warranted to assess to which degree this will be in a tolerable range.  相似文献   
59.
In times of reduced monetary resources of the current German health system, it is more and more difficult for the German physicians to comply with the high medicinal care standard and to practice economically. Nevertheless, the economical reasons cannot deny the high medical quality standards. Regarding the principle of the unity of jurisdiction, the validity of the social welfare law, that a performance has to be "just sufficient and suitable", must concur with the demand of liability law of "indication of the medical service". The economical duties reach their limit when they increase the risk for the patient. On the other hand, the economy interests have to be regarded by the "principle of the allowed risk". Therefore, it should be considered that in every single case the severity and probability of the risk has to be weighed against the cost aspect.  相似文献   
60.
This paper studies the relationship between a case-based decision theory (CBDT) and an ideal point model (IPM). We show that a case-based decision model (CBDM) can be transformed into an IPM under some assumptions. This transformation can allow us to visualize the relationship among data and simplify the calculations of distance between one current datum and the ideal point, rather than the distances between data. Our results will assist researchers with their product design analysis and positioning of goods through CBDT, by revealing past dependences or providing a reference point. Furthermore, to check whether the similarity function, presented in the theoretical part, is valid for empirical analysis, we use data on the viewing behavior of audiences of TV dramas in Japan and compare the estimation results under the CBDM that corresponds to a standard decision model with similarities and other various similarity functions and without a similarity function. Our empirical analysis shows that the CBDM with a similarity function, presented in this study, best fits the data.  相似文献   
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