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1.
A study was undertaken to determine the adequacy of vascularised jejunum to provide stable mucosal cover over a non-biological mandibular substitute. Employing a canine model, composite intra-oral bone-mucosal defects were created and reconstructed with a metal plate covered by a microvascular jejunal patch. These were followed for six months and were assessed clinically, histologically and radiologically. Rapid mucosal healing occurred in all cases. The autografts conformed to the contour of the prosthesis and adequate tongue mobility was preserved. All mandibles remained stable throughout the follow-up period. Histologically, short villi covered the jejunal grafts to three months whilst at six months both normal and abnormal jejunal mucosal morphology was evident.  相似文献   
2.
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
3.
Robert Sheen 《Microsurgery》1994,15(4):262-264
The intraoral mucosa subserves a multitude of structural and functional roles. This paper details the importance of this within the context of reconstruction. The various methods are reviewed historically. Also, both the experimental and clinical basis for using revascularized jejunum as mucosal reconstruction are presented. © 1994 Wiley-Liss, Inc.  相似文献   
4.
OBJECTIVE: We aimed to determine whether general practitioner GP hospitals, compared with alternative modes of health care, are cost- saving. METHODS: Based on a study of admissions (n = 415) to fifteen GP hospitals in the Finnmark county of Norway during 8 weeks in 1992, a full 1-year patient throughput in GP hospitals was estimated. The alternative modes of care (general hospital, nursing home or home care) were based on assessments by the GPs handling the individual patients. The funds transferred to finance GP hospitals were taken as the cost of GP hospitals, while the cost of alternative care was based on municipality and hospital accounts, and standard charges for patient transport. RESULTS: The estimated total annual operating cost of GP hospitals was 32.2 million NOK (10 NOK = 1 Pound) while the cost of alternative care was in total 35.9 million NOK. Sensitivity analyses, under a range of assumptions, indicate that GP care in hospitals incurs the lowest costs to society. CONCLUSION: GP hospitals are likely to provide health care at lower costs than alternative modes of care.   相似文献   
5.
Nitric oxide (NO) inhalation therapy has been employed in the management of acute respiratory distress syndrome (ARDS), in order to improve oxygenation. Several factors have been implicated as being responsible for the action of inhaled NO. Alveolar recruitment methods, such as prone positioning and a sufficient positive end expiratory pressure (PEEP), have been identified as having a positive impact on the NO response. A Recruitment maneuver (RM) was introduced for the treatment of ARDS, along with a lung protective strategy. Here, we hypothesized that a RM may further augment the oxygenation of patients treated with NO inhalation. Therefore, the effects of the inhalation of NO, either in combination with a RM, or separately, were evaluated on patients with ARDS for their enhancing action. 23 patients with ARDS were enrolled, and divided into three groups. The patients in group 1 (n=11) were treated with 5 ppm NO via inhalation, followed by a RM, applying a sustained inflation pressure of 30 - 35 cmH2O for 30 seconds. Group 2 (n=6) received a RM alone, while group 3 (n=3) was treated with NO inhalation alone. The oxygenation and hemodynamic parameters were obtained prior to, and 2, 12, and 24 h after, the respective treatment procedures. For group 1, the PaO2/FiO2 increased from its initial value of 171.8 +/- 67.8 to 203.2 +/- 90.0 2 h after NO inhalation. Further improvement was noted with the continual application of the RM reaching, 215.5 +/- 74.6 (p=0.05) and 254.2 +/- 109.5 (p < 0.05), after 12 and 24 h, respectively. Initially 7 of the subjects did not respond to NO inhalation, but 3 of these non-responders changed into responders 12 h after the RM. The changes in the PaO2/FiO2 from baseline at each time period were greater in group 1 than in the other groups, but with no statistical significance. The hemodynamics of the patients was not significantly altered during the entire study period. We conclude that the combined application of NO inhalation and a RM could be beneficial and safe for patients with ARDS, showing an enhancing effect in improvement of oxygenation.  相似文献   
6.
Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system.  相似文献   
7.
To evaluate the potential implication ofin vivo interferon production in the pathogenesis of different forms of acute and chronic hepatitis B virus infection, serum levels of interferon- and- were measured using immunoassay techniques in 20 patients with acute hepatitis B who subsequently cleared the virus (group Ia), 8 patients with acute hepatitis B who became HBsAg carriers (group Ib), 55 patients with chronic hepatitis B (group II), and 15 healthy controls. None of the controls had interferon- or- detectable in serum, while 15% and 100% of group Ia patients, 25% and 100% of group Ib patients, and 22% and 15% of group II patients, had raised serum levels of interferon- and-, respectively. Serum interferon- was detected significantly more frequently in group Ia and Ib patients than in controls and in group II patients. Among patients with acute hepatitis B, serum levels of interferon- and- showed no significant difference between group Ia and group Ib patients. Among patients with chronic hepatitis B, interferon- was detected significantly more frequently in patients with serum HBV-DNA (31.4% or 11/35) than in those without (5% or 1/20), whereas interferon- was detected significantly more frequently in patients with chronic active hepatitis (28% or 7/25) than in those with chronic persistent hepatitis (3.3% or 1/30). In conclusion, in acute hepatitis B, serum levels of interferon- and- did not show a significant difference between patients who subsequently cleared the virus and those who became HBsAg carriers. In chronic hepatitis B, the raised serum levels of interferon- correlated with the presence of viral replication, while the raised serum levels of interferon- correlated with the presence of histological evidence of active hepatitis.  相似文献   
8.
Risk factors for wound infection after cholecystectomy.   总被引:3,自引:0,他引:3  
BACKGROUND AND PURPOSE: Surgical site infection (SSI) after cholecystectomy is a common problem. The aim of this study was to identify the possible risk factors for the development of SSI. METHODS: 545 consecutive patients who received open (125) or laparoscopic (420) cholecystectomy due to gallbladder disease during the years 1998 to 2000 were included in the study. Potential risk factors including clinical features, biochemical data, and operative types were analyzed by univariate and multivariate analysis. RESULTS: The overall incidence of SSI was 4.4% (24/545). The wound complication rate was significantly lower in the laparoscopic group than in the open group (1.4% vs 14.4%, respectively). Factors associated with SSI found by univariate analysis (p < 0.05) included age, gender, acute cholecystitis, white blood cell count, serum albumin, blood glucose and bilirubin level, type of surgery, operative time and positive bile culture. Stepwise logistic regression analysis showed that abnormal blood glucose [odds ratio (OR), 4.7; 95% confidence interval (CI), 1.6 to 13.5], positive bile culture (OR, 3.5; 95% CI, 1.2 to 10.4), and open cholecystectomy (OR, 4.3; 95% CI, 1.3 to 13.6) were the most significant predictors of SSI. CONCLUSION: Poor control of diabetes mellitus before surgery, positive bile culture and open cholecystectomy significantly increased the rate of SSI. These findings indicate that better control of diabetes mellitus, and appropriate selection of surgical procedure and antibiotic regimen in the management of high-risk patients may reduce the incidence of postoperative SSI.  相似文献   
9.
HYPOTHESIS: Mutant p53 gene has lost its tumor suppression function and is considered to be a very important step in hepatocellular carcinoma development. We propose that the mutant p53 gene plays a role in its invasiveness and prognosis after resection. DESIGN: A case-controlled study. SETTING: A referral center. PATIENTS: Seventy-nine consecutive patients who underwent surgical resection for hepatocellular carcinoma entered this study. INTERVENTION: Tissue sections of resected hepatocellular carcinoma (deparaffinized and rehydrated from formalin-fixed and paraffin-embedded sections) were incubated with antihuman p53 monoclonal antibody and immunostained. The p53 result was scored without prior knowledge of the patients' status. A 10% immunopositivity was regarded as the threshold value. MAIN OUTCOME MEASURE: The immunopositive rate of p53 was 69.6% (55 of 79 patients). The clinical variables (age, sex, associated liver cirrhosis, hepatitis B virus infection, hepatitis C virus infection, serum alpha-fetoprotein, and Child-Pugh class); the histological variables (size, capsule, vascular permeation; grade of differentiation, and multinodularity); and postoperative course (recurrence, tumor-free interval, death, and survival period) were correlated with p53 immunopositivity. RESULTS: From univariate analysis, more patients with p53 positivity were male (92.7 vs 0%) (P<.001); had vascular permeation (80% vs 50%) (P =.007) (odds ratio [OR], 4.0); no complete capsule (83.6% vs 62.5%) (P =.04) (OR, 3.1); and daughter nodules (90.9% vs 70.8%) (P =.04) (OR, 4.1) than patients with negative p53 staining. From multivariate analysis, only sex and vascular permeation remained significant (P =.001 and P =.008, respectively). Although more patients with p53 positivity had tumor recurrence (78% vs 50%) (P =.01) and death (64% vs 33%) (P =. 01), the Cox proportional hazards model showed that p53 overexpression had only weak correlations with tumor-free interval and survival time (P =.09 and P =.08, respectively). CONCLUSIONS: Our results show that the biological behavior of the mutant p53 gene is strongly related to the invasiveness of hepatocellular carcinoma and may also influence the postoperative course. We suggest that the immunopositivity of the mutant p53 gene has a predictive role in the prognosis of patients with resected hepatocellular carcinoma.  相似文献   
10.
The physicochemical properties of the base and hydrochloride salt of the poorly water-soluble drug alpha-pentyl-3-(2-quinolinylmethoxy) benzenemethanol (REV 5901) were investigated in order to select an appropriate form of the drug for dosage form development. The pH-solubility profiles of both the base and the salt at 37 degrees C were identical and were in agreement with a pKa value of 3.67 determined by the UV spectral method. The solubility of the drug (approximately 0.002 mg/mL at pH 6) increased gradually with a decrease in pH and reached a value of 0.95 mg/mL at pH 1; at pH values less than 1, the solubility decreased due to the common-ion effect. The pHmax, i.e., the pH of maximum solubility of the drug was, therefore, 1.0. The role of the pHmax in the selection of a salt or base form of a compound was investigated. Due to the conversion of the salt to the base at the surface of the dissolving solid at pH values greater than pHmax, the dissolution rates of both the base and the salt were identical. In the solid state, the salt existed in anhydrous and monohydrate forms; the anhydrous salt converted to the hydrate at greater than 40% relative humidity, and the hydrate lost water at 40-60 degrees C. The thermal properties of the salt were indicative of its potential instability, which was confirmed by accelerated stability studies. The base existed in a stable crystalline solid form, and also in an oily liquid form which converted to crystals on standing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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