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71.
Background: Hand and distal forearm allotransplantation has advanced over the last 20 years from experimental to a viable treatment option for bilateral upper extremity amputation. Despite widespread growth of this field, there are few technical reports that elaborate the details of donor arm procurement. This article details a technique for rapid donor procurement through the elbow for mid to distal forearm-level hand allograft procurement. Methods: Nine arm procurements were performed on deceased tissue-only donors provided by the local organ procurement organization, including two bilateral and five unilateral cases. Technique highlights include using a fishmouth incision through the lateral and medical epicondyles, identification of the neurovascular structures, and disarticulating the elbow joint. Results: Procuring through the elbow provides straightforward anatomy, bypasses the need to cut through bone, and allows tissue allotransplantation teams to achieve procurement, flushing, and packaging within 20 minutes. Conclusions: Procurement through the elbow is a simple procedure that streamlines the process for multi-organ donors by minimizing the time needed for hand allograft procurement. Team coordination and surgical rehearsals are essential for successful hand and upper extremity procurement and allotransplantation.  相似文献   
72.
In 20 patients a continuous block of the lumbar plexus was administered after knee-joint surgery, and the analgesic effect of two different concentrations of bupivacaine was compared. The same volume of bupivacaine was given to both groups of patients: a bolus dose of 0.4 ml/kg, 0.5% or 0.25%, followed by infusion of 0.14 ml/kg/h, 0.25% or 0.125%, respectively, via a catheter placed in the neurovascular fascial sheath of the femoral nerve according to the "3-in-1 block" technique. The median morphine consumption during the first 16 h postoperatively was 6.0 mg when bupivacaine 0.5/0.25% was used and 9.5 mg when 0.25/0.125% was used. This difference is not significant. The visual analogue pain scores were also similar in the two groups (P greater than 0.05). All plasma concentrations were below 4 micrograms/ml, the highest concentration measured being 3.6 micrograms/ml. It is concluded that when used for a continuous block of the lumbar plexus after knee-joint surgery, bupivacaine in a concentration of 0.125% offers the same pain relief as a concentration of 0.25%, and the risk of toxic reactions is reduced.  相似文献   
73.
Two gene loci for the E1 subunit of the pyruvate dehydrogenase (PDH) complex have been mapped in the mouse by in situ hybridization. One locus maps to the X chromosome in the region F3–F4, the other to chromosome 19, in band B close to the centromere. This arrangement is exactly comparable to the situation in man where there is an X-linked PDH E1 locus and an autosomal locus on chromosome 4. Comparison of the regional localization of the human and mouse X-linked PDH E1 genes provides further information concerning sites of rearrangement of segments of the X chromosome during mammalian evolution. The human autosomal PDH E1 gene is a processed gene, which lacks the introns that are present in the X-linked gene. It codes for a testis-specific E1 subunit that is only expressed after the onset of spermatogenesis. The comparative mapping results in the mouse suggest that the genetic organization and pattern of expression of the two PDH E1 genes is the same in the two species.  相似文献   
74.
The authors present the results of surveys of directors of nursing and directors of pharmacy on the types and extensiveness of the policies their institutions have implemented to control the use of verbal and telephone orders. One hundred hospitals were selected at random from 874 hospitals meeting the following criteria: 250 beds or larger, general medical surgical, short stay, and nongovernmental. The survey results demonstrated that a significant number of hospitals are attempting to regulate the use of verbal and telephone orders. However, only 35.5% of the hospitals surveyed have any policies that prohibit the use of verbal orders when the physician is physically present on the unit where the order is given, in non-emergency and non-bedside procedure situations. Relative to the above policy, directors of nursing state that this policy is followed 41.1% of the time and directors of pharmacy in the same institutions state that the policy is adhered to 11.1% of the time. In addition to the survey, the authors explain situations that may serve as a source of medication errors when using verbal or telephone orders. They also offer several precautions to take when the use of verbal and telephone orders is absolutely necessary.  相似文献   
75.
This report describes the design, methods and clinical results of a prospective sequential multinational (5 countries) study conducted to evaluate the effects of subcutaneous sumatriptan on health-related quality of life, workplace productivity, clinical parameters and patient satisfaction. Adult patients with moderate to severe migraine initially received customary therapy for migraine episodes for 12 weeks, followed by 24 weeks' treatment with self-administered subcutaneous sumatriptan 6 mg. Demographic, baseline, health-related quality of life and patient satisfaction rating data were collected during visits to the clinic. Data relating to migraine symptoms, migraine therapy, work productivity and non-work activity time were collected on diary cards filled out by the patients. 749 patients were recruited to the study and 637 received at least 1 dose of sumatriptan. Overall, 75.5% of migraines were successfully treated within 2 hours with sumatriptan compared with 31.9% with customary therapy; 36% of patients reported complete relief at 2 hours with sumatriptan treatment compared with 1% of patients receiving customary therapy. 69% of patients successfully treated 70% of their migraines with sumatriptan within 2 hours, compared with 12% of patients with customary therapy. No serious adverse events were reported; 50% of patients reported an adverse event during the 12-week customary therapy phase and 89% of patients during the 24-week sumatriptan phase. These clinical results, which are consistent with those reported in randomised blinded studies of subcutaneous sumatriptan, suggest that relief of migraine symptoms occurs more often, and in less time, in patients receiving subcutaneous sumatriptan rather than customary therapy as their primary medication.  相似文献   
76.
77.
OBJECTIVE: Due to the thrombogenicity and permanent implant nature of metallic stents, bioresorable synthetic polymers have been proposed for stents and local drug delivery systems. Bioresorbable polyesters like poly(D,L-lactide) demonstrated excellent biocompatibility in various tissues. This paper describes a novel method for the molding of these polymers. The specific CESP-process (Controlled Expansion of Saturated Polymers) is characterised by the use of the plasticizer carbon dioxide and allows the incorporation of bioactive substances at physiologic temperatures into the polymer bulk and the production of complex designed implants. METHODS: The CESP-process is characterised by the exposure of an amorphous polymer to an inert gas at high pressure with a significant lower glass transition point. The plasticizing effect makes it possible to process polylactides at a temperature close to room temperature. The low process temperature constitutes a key advantage for thermally sensitive polymers and allows the incorporation of thermally sensitive pharmaceutical additives. To obtain some preliminary information on the biocompatibility, in vitro cell toxicity testing as well as drug release assessment was performed. RESULTS: Different polymer sheets were produced using the CESP-process. Cytotoxicity was not observed in any molded polymer material. According to the mechanical and biocompatibility results Poly(D,L-lactide) (P-DL-LA) was investigated in the CESP-process. Finite element analysis was used to test the possible geometry of an adequate stent. A helical design was chosen and a stent-prototype was produced using the CESP-process. Peroxidase activity as an incorporated marker enzyme could be measured over 6 weeks. Different drug release profiles were obtained due to various pore sizes of the polymer. CONCLUSIONS: The new CESP-process can be used to process biodegradable polymers and to mold different stent geometries without inducing cytotoxic effects to the material. Furthermore, this procedure permits the simultaneous incorporation of bioactive substances during the molding process. Drug release kinetics can be regulated by different pore sizes of the material.  相似文献   
78.
We have compared three different methods of epidural analgesia in labour, bupivacaine 2.5 mg/ml (group B), bupivacaine 0.625 mg/ml + sufentanil 1 microg/ml (group BS) and bupivacaine 0.625 mg/ml + sufentanil 1 microg/ml + epinephrine 1 microg/ml (group BSE). One hundred and forty parturients with a singleton fetus with cephalic presentation were randomly allocated to one of the three groups. Group BSE had significantly less pain than groups B and BS. Group B had a significantly higher degree of motor blockade assessed on the Bromage scale. Significantly, more women in group B required urinary bladder catheterization than in the two other groups and they also had significantly less urge to push during active delivery. The incidence of mild pruritus was 18% in group BS and 36% in group BSE. The frequency of instrumental delivery and caesarean section was low (12% and 6.4%, respectively) with no significant differences between the groups. All women were highly satisfied with the method of analgesia and 97% would prefer the same kind of pain alleviation at the next delivery. We conclude that epidural analgesia with low-dose bupivacaine and sufentanil is as good an analgesic method as high-dose bupivacaine. Addition of low-dose epinephrine improves the analgesia.  相似文献   
79.
Following certain major operative procedures, large amounts of tissue factor may be released from damaged tissues to venous blood. Mechanical and chemical injury to the collecting veins exposes subendothelial procoagulant proteins. This initiates a marked local hypercoagulable process. Subsequently, venous bloodborne procoagulant debris induce a substantial thrombin generation as blood passes the lung capillaries. Thus, the lungs seem to have a central role in the mechanisms of hypercoagulability in high-risk patients. Hypercoagulable blood is squeezed out in the peripheral circulation and may favor thrombosis formation both in central and peripheral vessels. In addition, reduced venous blood flow for several days to weeks after the operation may put these patients at-risk for thromboembolic complications for a long time. Several predisposing genetic and acquired factors associated with thrombophilia have been proposed to contribute to this hypercoagulable process. However, few studies and conflicting results have been reported. The clinical penetrance of the described thrombophilic abnormalities and their contribution to the hypercoagulable process in "high-risk" patients are, at present, unclear. The post-traumatic hypercoagulability seems to be a systemic phenomenon, at least following major orthopedic surgery. Cardiorespiratory and vascular complications play a prominent role as a cause of death and morbidity during and after this kind of surgery.  相似文献   
80.
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