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901.
AC Galloway SB Colvin EA Grossi MA Parish AT Culliford T Asai NM Rofsky JC Weinreb S Shapiro FG Baumann 《Canadian Metallurgical Quarterly》1993,105(5):781-8; discussion 788-90
During an 8-year period (1984 to 1991) 66 patients (mean age 59 years, range 26 to 84 years) with type A aortic dissection (60 ascending aorta tears, 6 arch tears; 35 acute, 31 chronic) had surgical repair by a continuous suture-graft inclusion technique. Hypothermic circulatory arrest (16 degrees C) was used in 58 patients (35/35 acute, 23/31 chronic; mean arrest time 26 minutes, range 10 to 55 minutes). Fifty-two patients had hemiarch repair and 6 had total arch replacement. Aortic valve disease necessitated treatment in 38 patients (1 valved conduit, 20 valve replacements, 17 valve repairs). Recently 11 patients had valve repair by reconstruction of the native aortic root, by means of techniques similar to those used for homograft valve insertion. Operative mortality was 9% (14% acute, 3% chronic). Stroke occurred in 2 patients (3%) and was fatal in both. Variables suggestive of increased operative risk by univariate analysis were acuteness (p = 0.12), visceral ischemia (p = 0.12), and preoperative shock (p = 0.13). No variable was significant by multivariate analysis. Overall actuarial survival at 48 months was 77%, with 3 late deaths from a ruptured distal aneurysm. Late computed tomography or magnetic resonance imaging scan was done in 28 patients at a mean interval of 33 months. These studies identified 1 patient with a pseudoaneurysm requiring reoperation and 3 patients with contained flow between the graft and the wrap. Three patients required late operation: 1 for pseudoaneurysm, 1 for arch dissection, and 1 for repair of a distal aneurysm. 相似文献
902.
The purpose of this article is to describe how nurse instructors understand nursing and the necessary conditions for high quality nursing care. The approach of the study was inductive and based on phenomenology and a sociological field research method, i.e. grounded theory. It emerged that the core of nursing is a process, termed here caring, with three stages. Three types of caring emerged. Understanding the client, the art of nursing, co-operation between the nurse and other health care professionals were found to be necessary conditions for a high quality nursing care and it was also found that it is not possible to separate caring from the society and its history. 相似文献
903.
G da Silva JC Santos S Martins J Gíria CA Pereira 《Canadian Metallurgical Quarterly》1994,7(3):155-163
The results of 3679 patients, with intestinal obstruction, submitted to emergency surgery at the UUC-HCL between November 1981 and November 1991, were analysed in a general way, with the use of a graphic presentation. In the mechanical group, hernia (1604 cases), adhesions and bands (568 cases) and cancer (713 cases) were the most common pathologies; intestinal ischaemia (143 cases) was the most frequent form in the neurogenic group. Surgical therapy was evaluated in a general way. However, we comment on the evolution of primary surgical treatment of colorectal cancer in obstruction (625 cases). The mortality rate was in general: 10.8% (adults). In relative terms, the main features were intestinal ischaemia (39%), cancer (23%) and intestinal volvulus (22%). 相似文献
904.
The RNA genome of tobacco etch potyvirus (TEV) was engineered to express bacterial beta-glucuronidase (GUS) fused to the virus helper component proteinase (HC-Pro). It was shown previously that prolonged periods (approximately 1 month) of TEV-GUS propagation in plants resulted in the appearance of spontaneous deletion variants. Nine deletion mutants were identified by nucleotide sequence analysis of 40 cDNA clones obtained after polymerase chain reaction amplification. The mutants were missing between 1,741 and 2,074 nucleotides from TEV-GUS, including the sequences coding for most of GUS and the N-terminal region of HC-Pro. This region of HC-Pro contains determinants involved in helper component activity during aphid transmission, as well as a highly conserved series of cysteine residues. The deletion variants were shown to replicate and move systemically without the aid of a helper virus. Infectious viruses harboring the two largest HC-Pro deletions (termed TEV-2del and TEV-7del) were reconstructed by subcloning the corresponding mutated regions into full-length DNA copies of the TEV genome. Characterization of these and additional variants derived by site-directed mutagenesis demonstrated that deletion of sequences coding for the HC-Pro N-terminal domain had a negative effect on accumulation of viral RNA and coat protein. The TEV-2del variant possessed an aphid-nontransmissible phenotype that could be rescued partially by prefeeding of aphids on active HC-Pro from another potyvirus. These data suggest that the N-terminal domain of HC-Pro or its coding sequence enhances virus replication or genome expression but does not provide an activity essential for these processes. The function of this domain, as well as a proposed deletion mechanism involving nonhomologous recombination, is discussed. 相似文献
905.
L Palazzo G Roseau A Ruskone-Fourmestraux P Rougier S Chaussade JC Rambaud D Couturier JA Paolaggi 《Canadian Metallurgical Quarterly》1993,25(8):502-508
Endoscopic ultrasonography (EUS) and endoscopy were prospectively performed and compared to the histopathologic findings of the resection specimens in 24 patients with primary gastric lymphoma (PGL). On EUS, three types of PGL could be differentiated, a superficial type (n = 10), an infiltrating type (n = 12) and a tumorous type (n = 2). In the correct assessment of surface extension of the tumors, endoscopy and EUS agreed in 37.5% of cases and EUS showed more extensive disease than endoscopy in 58% of cases. However, in comparison to the resection specimens, EUS still underestimated the tumor surface extension in 37.5% of cases; this was mainly in low grade malignant PGL. The depth of tumor infiltration was correctly determined on EUS compared to the resection specimens in 91.5% of cases. Sensitivity, specificity and accuracy of diagnosing lymph node metastases were 100%, 80% and 83%, respectively. We conclude that EUS is a useful pre-therapeutic staging tool for primary gastric lymphoma but there remain some problems in determining the longitudinal and circular tumor spread in order to accurately guide the extent of gastric resection. 相似文献
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907.
Adverse reactions to seafood are common and may cause many types of symptoms that are difficult to define. The nature of these reactions are variable including allergic and toxic reactions as well as infectious diseases. The differentiation between these entities is essential in choosing therapy. We describe 9 patients with IgE mediated allergic reactions due to crustaceans and fish diagnosed from case history, clinical findings, skin tests and specific IgE antibodies. Most symptoms of a IgE mediated allergic reaction appear within 30 minutes after ingestion. Characteristics clinical features may include an urticarial rash, gastrointestinal symptoms and even anaphylaxis. In this case immediate therapy with intravenous glucocorticoids, antihistamine and perhaps subcutaneous epinephrine is required. 相似文献
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