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101.

Introduction

The aim of this study was to compare the effect of the EndoVac irrigation system (SybronEndo, Orange, CA) and conventional endodontic needle irrigation on sealer penetration into dentinal tubules.

Methods

Forty single-rooted, recently extracted human maxillary central incisors were randomly divided into 2 groups according to the irrigation technique used: conventional endodontic needle irrigation and EndoVac irrigation. All teeth were instrumented using the ProFile rotary system (Dentsply Maillefer, Ballaigues, Switzerland) and obturated with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) labeled with fluorescent dye. Transverse sections at 1, 3, and 5 mm from the root apex were examined using confocal laser scanning microscopy. The total percentage and maximum depth of sealer penetration were then measured.

Results

Mann-Whitney test results showed that EndoVac irrigation resulted in a significantly higher percentage of sealer penetration than conventional irrigation at both the 1- and 3-mm levels (P < .05). However, no difference was found at the 5-mm level. The 5-mm sections in each group showed a significantly higher percentage and maximum depth of sealer penetration than did the 1- and 3-mm sections (P < .05).

Conclusions

The EndoVac irrigation system significantly improved the sealer penetration at the 1- to 3-mm level over that of conventional endodontic needle irrigation.  相似文献   
102.
Objective. Because exposure to streptococcal antigens might be a major disease activity—provoking factor in Behçet's disease, this study was undertaken to evaluate the effectiveness of benzathine penicillin in the prophylaxis of recurrent arthritis episodes during the course of this disease. Methods. A prospective, randomized study design was used to allocate patients to receive colchicine alone or colchicine plus benzathine penicillin for 24 months. Results. The duration, severity, and pattern of arthritis episodes were found to be similar in the 2 treatment groups, but the number of arthritis episodes was significantly reduced, and the duration of episode-free time significantly prolonged, in the penicillin group compared with the colchicine-alone group. Conclusion. Penicillin treatment was demonstrated to offer adjunctive benefits in the prevention of arthritis episodes which are not obtainable with colchicine monotherapy. This finding could provide additional evidence for antigen triggering in the pathogenesis of Behçet's disease.  相似文献   
103.
The combination of hepatitis B immunoglobulin and potent nucleos(t)ide analogs after liver transplantation is considered as the standard of care for prophylaxis against hepatitis B virus recurrence. However, the recommended doses, route of administration, and duration of HBIG administration remain unclear. Moreover, hepatitis B immunoglobulin-free prophylaxis with potent nucleos(t)ide analogs has shown promising disease outcomes in preventing hepatitis B virus recurrence. The current recommendations, produced by the Turkish Association for the Study of the Liver, Acute Liver Failure and Liver Transplantation Special Interest Group, suggest a reduced need for hepatitis B immunoglobulin administration with effective long-term suppression of hepatitis B virus replication using potent nucleos(t)ide analogs after liver transplantation.  相似文献   
104.
Although tension-free techniques of hernia repair using synthetic meshes have yielded encouraging results, the best method of inguinal hernia repair is still unclear. The aim of this study was to compare the responses of inflammatory mediators and postoperative pain relief following laparoscopic total extraperitoneal (TEP) hernioplasty, open tension-free mesh hernioplasty (Lichtenstein), posterior preperitoneal mesh hernioplasty (Nyhus procedure), and Bassini procedure. Patients with primary inguinal hernia were randomized in the operating room to undergo one of these repair techniques. Group I comprised 24 patients treated by Lichtenstein procedure; Group II comprised 21 patients treated by Nyhus procedure; Group III comprised 19 patients treated by Bassini procedure; and Group IV comprised 20 patients treated by laparoscopic TEP mesh hernioplasty. Postoperative pain levels following hernia repair were compared by measuring the use of patient-controlled analgesia (PCA) during the 24 hours after surgery. Serum samples withdrawn before surgery and 48 hours after surgery were assayed for C-reactive protein (CRP) content. Patient characteristics, operating time, and operative and early complications were noted. Serum CRP levels rose markedly following Nyhus (184.5 +/- 41.6 mg/L), Lichtenstein (138.4 +/- 72.5 mg/L), and Bassini repair (137.2 +/- 55.9 mg/L) compared with that of patients who underwent TEP mesh hernioplasty (55.5 +/- 41.2 mg/L). There were also significant differences in the postoperative need for analgesics via PCA among patients undergoing Nyhus (382.9 +/- 189.1 mg), Bassini (303.2 +/- 173.7 mg), and Lichtenstein (253.9 +/- 129.3) procedures compared with 196.6 +/- 148.8 mg for the TEP mesh hernioplasty group. Patients in the Lichtenstein group also had significantly less need of analgesics than those in the Nyhus and Bassini groups. In conclusion, TEP mesh hernioplasty is less traumatic and yields less postoperative pain than the Nyhus, Lichtenstein, and Bassini procedures.  相似文献   
105.
Microsatellite instability (MSI) is a form of genomic instability associated with defective DNA mismatch repair in tumors. MSI is found in 85-90% of hereditary nonpolyposis colorectal cancer cases; however, its occurrence in breast carcinogenesis still remains to be clarified. In addition, data are limited on the incidence of MSI in the medullary subtype. The purpose of this study was to investigate the occurrence of MSI in medullary breast cancer (MBC). The study included a total of 16 patients with MBC, nine with typical and seven with atypical histology. The incidence of MSI in five microsatellite loci (D2S123, D3S1611, D17S807, D17S796 and Xq11-12) was determined by comparing paired normal and tumor tissue DNA after PCR amplification from paraffin-embedded tissues. All 16 tumors showed stability at five loci. Although the number of microsatellite markers and DNA samples may limit the value of our results, we conclude that the MSI phenotype is uncommon in human MBC.  相似文献   
106.
Background: To improve clinical outcomes, noninvasive imaging modalities have been proposed to measure and monitor atherosclerosis. Common carotid intima‐media thickness (CIMT) and brachial artery flow‐mediated dilatation (FMD) have correlated with coronary atherosclerosis. Recently, the color M‐mode‐derived propagation velocity of descending thoracic aorta (AVP) was shown to be associated with coronary artery disease (CAD). Methods: CIMT, FMD, and AVP were measured in 92 patients with CAD and 70 patients having normal coronary arteries (NCA) detected by coronary angiography. Patients with acute myocardial infarction, renal failure or hepatic failure, aneurysm of aorta, severe valvular heart disease, left ventricular ejection fraction <40%, atrial fibrillation, frequent premature beats, left bundle branch block, and inadequate echocardiographic image quality were excluded. Results: Compared to patients with normal coronary arteries, patients having CAD had significantly lower AVP (29.9 ± 8.1 vs. 47.5 ± 16.8 cm/sec, P < 0.001) and FMD (5.3 ± 1.9 vs. 11.4 ± 5.8%, P < 0.001) and higher CIMT (0.94 ± 0.05 vs. 0.83 ± 0.14 mm, P < 0.001) measurements. There were significant correlations between AVP and CIMT (r =−0.691, P < 0.001), AVP and FMD (r = 0.514, P < 0.001) and FMD and CIMT (r =−0.530, P < 0.001). Conclusions: The transthoracic echocardiographic determination of the color M‐mode propagation velocity of the descending aorta is a simple practical method and correlates well with the presence of carotid and coronary atherosclerosis and brachial endothelial function. (Echocardiography 2010;27:300‐305)  相似文献   
107.
A three-month-old boy presented with growth failure, skeletal abnormalities, otitis media and pancytopenia. Exocrine pancreatic insufficiency was confirmed by low levels of fecal elastase. He was diagnosed as Shwachman-Diamond syndrome by clinical and laboratory findings. The diagnosis was confirmed by sequence analysis for SBDS gene on chromosome seven revealing compound heterozygous mutation, which are c.258+2T-C and c.183-184TA-CT. Matched unrelated donor screening for hematopoietic stem cell transplantation was initiated. Unfortunately, he died of respiratory difficulty at 5 months of age. Our case is the youngest patient whose presumptive Shwachman-Diamond syndrome diagnosis was confirmed by molecular analysis.  相似文献   
108.
This phase II study is the first prospective evaluation of bortezomib-dexamethasone as second-line therapy for relapsed/refractory multiple myeloma. A total of 163 patients were enrolled to receive four cycles of bortezomib-dexamethasone. Patients were investigator-assessed for response at cycle 5 Day 1, then treated as follows: responding patients received another four cycles of bortezomib-dexamethasone, while patients with stable disease were subsequently randomized to sequential treatment with a further four cycles of bortezomib-dexamethasone alone or with added cyclophosphamide or lenalidomide. The primary end point was response to sequential therapy; however, this could not be evaluated because investigator-assessed response rates to bortezomib-dexamethasone after four cycles were high, and an insufficient number of patients were randomized to sequential treatment per protocol. Among all 163 patients, validated best confirmed response rate was 66%, including 37% complete/very good partial responses; median response duration was 9.7 months. After a median follow up of 16.9 months, median time to progression and progression-free survival were 9.5 and 8.6 months, respectively; estimated 1-year overall survival was 81%. Median glomerular filtration rate improved from baseline during treatment. Among 58 patients with baseline glomerular filtration rate below 50 mL/min, 24 had renal responses. Grade 3/4 adverse events included: thrombocytopenia (17%), anemia (10%), constipation (6%), peripheral sensory neuropathy (5%), and polyneuropathy (5%). Overall, 57% of neuropathy events improved/resolved; median time to improvement was 2.1 months. These findings suggest bortezomib-dexamethasone represents an active, feasible second-line treatment option for patients with relapsed/refractory myeloma.  相似文献   
109.
110.
Paraffin-embedded primary tumor specimens from 48 patients with breast cancer were examined for DNA ploidy, S-phase fraction (SPF), and concanavalin A (Con A) reactivity. The results were correlated with clinicopathological prognostic factors, including patients' age and menopausal status, stage of disease, nuclear grade, and size of the primary tumor. There were no associations among ploidy, SPF, Con A reactivity, and menopausal status, stage of disease, or size of the primary tumor. However, among patients who were 50 years or older, 81 % had diploid tumors and 73% had good reactivity (3+ or better staining score) with Con A. In contrast, among patients who were younger than 50 years, 45% had diploid tumors (P < 0.05) and 21% had good Con A reactivity (P < 0.05). Seven of 19 (37%) poorly differentiated tumors and 7 of 9 (78%) moderately differentiated tumors had good reactivity with Con A (P < 0.05). Reactivity of tumor cells with Con A in primary breast cancer tissues deserves further evaluation as a potential biomarker of prognosis. © 1994 Wiley-Liss, Inc.  相似文献   
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