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991.
The present study aimed to determine whether current commercial immunoassays are adequate for detecting anti-Omicron antibodies. We analyzed the anti-SARS-CoV-2 antibody response of 23 unvaccinated individuals 1–2 months after an Omicron infection. All blood samples were tested with a live virus neutralization assay using a clinical Omicron BA.1 strain and four commercial SARS-CoV-2 immunoassays. We assessed three anti-Spike immunoassays (SARS-CoV-2 IgG II Quant [Abbott S], Wantaï anti-SARS-CoV-2 antibody ELISA [Wantaï], Elecsys Anti-SARS-CoV-2 S assay [Roche]) and one anti-Nucleocapsid immunoassay (Abbott SARS-CoV-2 IgG assay [Abbott N]). Omicron neutralizing antibodies were detected in all samples with the live virus neutralization assay. The detection rate of the Abbott S, Wantai, Roche, and Abbott N immunoassays were 65.2%, 69.6%, 86.9%, and 91.3%, respectively. The sensitivities of Abbott S and Wantai immunoassays were significantly lower than that of the live virus neutralization assay (p = 0.004, p = 0.009; Fisher's exact test). Antibody concentrations obtained with anti-S immunoassays were correlated with Omicron neutralizing antibody concentrations. These data provide clinical evidence of the loss of performance of some commercial immunoassays to detect antibodies elicited by Omicron infections. It highlights the need to optimize these assays by adapting antigens to the circulating SARS-CoV-2 strains.  相似文献   
992.
993.
994.
The effect of inhibition of nitric oxide synthesis and guanylate cyclase on the peripheral antinociceptive effect of morphine was assessed by using the formalin test in the rat. Saline, NG-monomethyl-

-arginine, a nitric oxide synthesis inhibitor (50 μg) and methylene blue, a guanylate cyclase inhibitor (500 μg), did not exhibit any antinociceptive activity. However, morphine (10 μg) produced a significant antinociceptive effect in phases 2a and 2b, which was reduced by pretreatment with either NG-monomethyl-

-arginine or methylene blue. These results suggest that the local administration of morphine induces antinociception by the activation of the

-arginine–nitric oxide–cGMP pathway.  相似文献   
995.
We herein present a study conducted on 14 patients presenting cancer of the lower rectum or of the anal canal (10 adenocarcinomas and 4 squamous-cell carcinomas) and submitted to the Miles abdominal perineal resection in which a new perineal sphincter was constructed. PURPOSE: The aim of this study was to evaluate the efficacy of this new perineal sphincter constructed by transposing the gracilis muscles around an orthotopic colostomy in the attempt to avoid a permanent abdominal colostomy. METHODS: In all cases both gracilis muscles were employed. The right one was placed along the posterior wall of the pelvis and fixed to the controlateral ischiatic tuberosity, creating a sling comparable to the levator ani muscles. The left gracilis was passed around the colon and attached to the ipsilateral or controlateral tuberosity according to its length, reconstructing a muscular ring. The entire procedure was performed in one step in nine cases and in more steps in the remaining five. RESULTS: Of the 14 operated patients, 2 died of vascular disease and 1 developed necrosis of the colonic stump which required reconversion to an abdominal colostomy. Of the remaining 11 patients available for long-term evaluations, 8 showed adequate stool control. The remaining three manifested an incomplete level of continence. During the three-year follow-up period, all patients were evaluated by clinical examination, defecography, endoluminal ultrasonography, nuclear magnetic resonance, CT scan, and endoluminal manometry. CONCLUSION: This neosphincter realizes an elastic stenosis responsible for an efficient level of continence. Best results are observed in the young and educated patients submitted to surgery in two steps. Contraindications to this surgery seem to be advanced cancer, old age, and obesity.  相似文献   
996.
PURPOSE: We herein report our experience with transanal endoscopic microsurgery. The new technique combines an endoscopic view and access of the rectum under gas insufflationviaa stereoscopic telescope with all conventional surgical maneuvers such as tissue preparation, coagulation and control of bleeding, irrigation, suction, and, finally, suturing of the parietal defect. METHODS: The main indication for transanal endoscopic microsurgery is the removal of broad-based sessile polyps and excision of early rectal cancers. We performed local excision of pT2, G1-2 adenocarcinomas and excision of advanced rectal cancer in high-risk patients. The reported series includes 35 consecutive patients, who have been enrolled in a prospective clinical trial. Five patients were excluded for different reasons. The patients were submitted to 29 total wall excisions with or without perirectal fat and one mucosectomy. RESULTS: Postoperative histologic examination showed 9 adenomas and 21 adenocarcinomas. Morbidity included 2 (5.6 percent) perioperative and 2 (5.6 percent) late complications. There was no operative mortality and the mean postoperative hospital course was six days. All patients are in follow-up observation with a mean time of 10.3 months. In the group of adenomas and adenocarcinomas, we did not observe local recurrence. CONCLUSIONS: Considering our experience with the overall results reported by other authors, we believe that transanal endoscopic microsurgery is the procedure of choice for the treatment of rectal polyps and early rectal cancers provided strict patient selection criteria are met.  相似文献   
997.
As the country strives to produce larger numbers of generalist physicians, considerable controversy has arisen over whether or not generalist applicants can be identified, recruited, and influenced to keep a generalist-oriented commitment throughout medical training. The authors present new and existing data to show that: 1) preadmission (BA/MD or post-baccalaureate) programs can help to identify generalist-oriented students; 2) characteristics determinedat admission to medical school are predictive of future generalist career choice; 3) current inpatient-oriented training programs strongly push students away from a primary care career; 4) women are more likely than men to choose generalist careers, primarily because of those careers’ interpersonal orientation; and 5) residency training programs are able to select applicants likely to become generalists. Therefore, to produce more generalists, attempts should be made to encourage generalist-oriented students to enter medical schools and to revise curricula to focus on outpatient settings in which students can establish effective and satisfying relationships with patients. These strategies are most likely to be successful if enacted within the context of governmental and medical school-based changes that allow for more reimbursement and respect for the generalist disciplines.  相似文献   
998.
Two districts in Recife (Santo Amaro and Campo Grande) and two districts in Olinda (Sapucaia and Salgadinho), were selected for a comparative study of bancroftian filariasis in Greater Recife. Selection parameters included similar socio-economic, demographic, and endemic levels of lymphatic filariasis. In the districts studied, streets were chosen randomly. These clusters consisted of 110 people each. A population sample was stratified by sex and age: 0-4, 5-9, 10-14, 15-19, 20-29, 30-39, 40-49, 50-59 and 60 years old and over. The parasitological data were obtained by measuring thick blood smears (60 micro l), collected from 8:00 to 12:00 PM and processed and stained with hematoxylin. The data were described in tables, and logarithimic expression graphics were used to analyze parasitic densities. In general, Recife showed a prevalence of 13.5%, and Olinda 12.3%. Mean parasitic densities were 41 and 70 microfilariae/60 micro l (mf/60 micro l), respectively. Higher microfilaremic rates were observed in Recife for the 20-29-year age bracket and in Olinda in the 30-39-year bracket. The authors concluded that the disease has returned to former endemic levels, and the data described call for a reevaluation of control campaigns carried out by the Brazilian National Health Foundation, since the endemic has already reached serious proportions.  相似文献   
999.
1000.
The Morgagni hernia occurs behind the sternum and is a rare diaphragmatic defect although the late diagnosis may result in important clinic symptoms and poor prognosis. The authors present a case report of a child with 11 months and respiratory symptoms with chronic pulmonary infections and several hospitalizations without etiologic diagnosis. The conclusion was for the early Morgagni hernia diagnosis and the prevention of chronic complications.  相似文献   
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