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141.
142.
Background. After coronary artery bypass grafting procedures, a higher incidence of morbidity and mortality has been reported in diabetic patients. We tested whether coronary artery bypass grafting in diabetics affects the endothelin-1 and nitric oxide coronary effluent profile during reperfusion.

Methods. Twenty-one consecutive patients (9 with type II diabetes mellitus, 12 non-diabetics) underwent coronary artery bypass grafting by one surgeon. The two groups did not differ in preoperative ejection fraction, Parsonnet score, number of vessels bypassed, or cross-clamp time. Each patient was treated in the same intraoperative manner with single atrial, aortic, and antegrade and retrograde cardioplegia (CPL) cannulas. Cold CPL arrest was by antegrade and retrograde infusion of modified Buckberg CPL solution. Warm CPL solution was infused before reperfusion. Coronary sinus blood samples were obtained for estimation of endothelin-1 and nitrite plus nitrate before CPL arrest and at 1 and 15 minutes after each of 2 reperfusion periods.

Results. In diabetics, endothelin-1 was significantly increased at all reperfusion times as compared with non-diabetics. Nitrite plus nitrate levels were significantly higher in patients with diabetes than in those without, but did not change with time in either of the groups.

Conclusions. Reperfusion after CPL during coronary artery bypass grafting procedure can trigger the release of endothelin-1 in patients with diabetes mellitus. This may favor increased vascular tone or positive inotropic responses after coronary artery bypass grafting and may contribute to significant cardiovascular consequences in diabetic patients.  相似文献   

143.
Background: The authors investigated whether practice patterns of bariatric surgeons correlate with published data regarding metabolic deficiencies after Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD). Methods: 109 surgeons completed a questionnaire to determine use of supplements and frequency of lab tests. Results: Regarding supplements routinely prescribed after RYGB, 96% of surgeons gave multivitamins, 63% gave iron, and 49% gave vitamin B12. After BPD, 96% of surgeons gave multivitamins, 67% gave iron, 42% gave vitamin B12, 97% gave calcium, 63% gave fat-soluble vitamins, and 21% gave protein supplements. Regarding laboratory tests obtained routinely after RYGB, 95% of surgeons do complete blood counts, 56% do iron determinations, 66% do vitamin B12 determinations, 58% do folate determinations, 76% do electrolyte determinations, and 8% test for proteins. After BPD, 96% of surgeons do complete blood counts, 80% do iron determinations, 67% do vitamin B12 determinations, 71% do folate determinations, 88% do electrolyte determinations, 84% do protein determinations, and 46% test for fat-soluble vitamins. Regarding frequency of blood tests, after RYGB, 22% of surgeons obtain them after 3 months, 33% after 6 months, and 41% after 12 months; 4% do not routinely obtain postoperative laboratory tests. After BPD, 46% of surgeons obtain them after 3 months, 33% after 6 months, and 16% after 12 months; one does not obtain laboratory tests. Surgeons estimated these deficiencies after RYGB: 16% iron, 12% vitamin B12, 14% anemia, 5% protein, and 3% calcium. They estimated these deficiencies after BPD: 26% iron, 11% vitamin B12, 21% anemia, 18% protein, 16% calcium, and 6% fat-soluble vitamins. The estimated incidence of deficiencies after RYGB was considerably lower than the published incidence. Unnecessary tests were commonly performed (electrolytes after RYGB). Conclusion: Despite wide variations in the performance of laboratory tests and the use of supplements, the practice patterns of most surgeons protect patients from developing severe metabolic deficiencies after RYGB and BPD.  相似文献   
144.
145.

Background

Even after surgery, hepatocellular carcinoma (HCC) has poor prognosis; adjuvant therapy is needed to improve effectively the outcome of HCC patients. We evaluated the efficacy of cytokine-induced killer (CIK) cell infusion as an adjuvant therapy for postoperative HCC patients.

Methods

A total of 410 patients were studied retrospectively (January 2002 to January 2007): 206 received surgery alone; 204 received surgery and at least four cycles of CIK cell transfusion (CIK group). Kaplan–Meier and Cox regression analyses were used to explore differences in OS between two groups.

Results

The CIK group overall survival rates were significantly higher than that of the surgery-alone group (log-rank test; p = 0.0007). Multivariate survival analysis showed that CIK cell treatment was an independent prognostic factor. In subgroup analysis, patients who received ≥8 cycles of CIK cell transfusion exhibited significantly better survival than the <8 cycle group (p = 0.0272). There was no significant difference in overall survival in patients with ≤5-cm tumors between the CIK and surgery-alone groups (p = 0.7567). However, in patients with >5-cm tumors, the CIK group displayed significantly better overall survival than the surgery-alone group (p = 0.0002).

Conclusions

Postoperative immunotherapy with CIK cell transfusion may be an effective adjuvant treatment for improving the outcomes of HCC patients; >8 cycles of CIK cell transfusion may ensure that patients derive maximal benefits. Moreover, patients with large tumors might benefit more from CIK cell adjuvant treatment than patients with small tumors.  相似文献   
146.

Background

Although many etiological theories have been proposed for osteochondritis dissecans (OCD), its etiology remains unclear. Histological analysis of the articular cartilage and subchondral bone tissues of OCD lesions can provide useful information about the cellular changes and progression of OCD. Previous research is predominantly comprised of retrospective clinical studies from which limited conclusions can be drawn.

Questions/purposes

The purposes of this study were threefold: (1) Is osteonecrosis a consistent finding in OCD biopsy specimens? (2) Is normal articular cartilage a consistent finding in OCD biopsy specimens? (3) Do histological studies propose an etiology for OCD based on the tissue findings?

Methods

We searched the PubMed, Embase, and CINAHL databases for studies that conducted histological analyses of OCD lesions of the knee and identified 1560 articles. Of these, 11 met our inclusion criteria: a study of OCD lesions about the knee, published in the English language, and performed a histological analysis of subchondral bone and articular cartilage. These 11 studies were assessed for an etiology proposed in the study based on the study findings.

Results

Seven of 11 studies reported subchondral bone necrosis. Four studies reported normal articular cartilage, two studies reported degenerated or irregular articular cartilage, and five studies found a combination of normal and degenerated or irregular articular cartilage. Five studies proposed trauma or repetitive stress and two studies proposed poor blood supply as possible etiologies.

Conclusions

We found limited research on histological analysis of OCD lesions of the knee. Future studies with consistent methodology are necessary to draw major conclusions about the histology and progression of OCD lesions. Inconsistent histologic findings have resulted in a lack of consensus regarding the presence of osteonecrosis, whether the necrosis is primary or secondary, the association of cartilage degeneration, and the etiology of OCD. Such studies could use a standardized grading system to allow better comparison of findings.  相似文献   
147.
That a contractile actin isoform has been found in cells of other cartilage tissues in healing and disease states prompted this investigation of the presence of alpha-smooth muscle actin (alpha-SMA) in pathological human intervertebral disc tissue. The presence of this isoform has been reported in human intervertebral disc specimens obtained at autopsy from subjects for whom there were no reported symptoms. An objective of this study was to evaluate the cell density and percentage of alpha-SMA-containing cells in pathological nucleus pulposus tissue obtained from lumbar disc surgery from 17 patients. Additionally, explants of nucleus pulposus material were cultured to determine how alpha-SMA expression changed with time in vitro. Seventy-six 5-mm diameter explants (approximately 2 mm thick) pooled from six lumbar surgeries were cultured for 1, 2, 4, or 6 weeks. Microtomed sections of paraffin-embedded specimens were stained with hematoxylin and eosin or a monoclonal antibody to alpha-SMA. Histologically, cells were categorized as to alpha-SMA phenotype (positive or negative), and the areal cell density was determined. The evaluation of the cultured nucleus pulposus explants also included documentation of the percentage of cells that were round or elongated and the percentage of the cells that were part of a group (group: >/= 2 cells). Every nucleus pulposus section exhibited the presence of alpha-SMA-containing cells, which accounted for approximately 24 percent of the cells in vivo. In vivo, the cell density was significantly higher in older individuals (p = 0.02). The average time for cell outgrowth from the explants was 8.6 days. Approximately 10-15 percent of the cells in the explants stained positive for alpha-SMA. The time in culture had no significant effect on any of the outcome measures except the percentage of alpha-SMA-containing cells that were round (p = 0.008), with values decreasing through 4 weeks and then slightly rising at 6 weeks. The role of alpha-SMA in intervertebral disc pathology warrants further investigation.  相似文献   
148.
BACKGROUND: Body dysmorphic disorder is a relatively common condition in patients seeking elective surgery. Little has been written, however, in the dermatologic surgery literature about body dysmorphic disorder, where proper recognition and management of this disorder is needed during this time of increased demand for aesthetic dermatologic surgery. OBJECTIVE: The objective was to review the prevalence, demographics, clinical features, treatment approaches, and referral suggestions for patients with body dysmorphic disorder in an attempt to facilitate care of such patients in a general dermatologic surgical practice. METHODS: We reviewed the dermatologic, cosmetic surgical, and psychiatric literature regarding body dysmorphic disorder and related disorders. RESULTS: Body dysmorphic disorder is observed in 6% to 15% of dermatologic and cosmetic surgery patients and in 2% of the general population. Surgical treatment of patients with body dysmorphic disorder typically leads to no change or worsening of symptoms in the majority of patients. The use of screening questionnaires and observation for hallmark features are helpful for clinicians in managing patients with body dysmorphic disorder. Psychiatric referral is desirable, because cognitive behavioral therapy and pharmacologic intervention with selective serotonin reuptake inhibitors are often efficacious. CONCLUSIONS: Body dysmorphic disorder is often underdiagnosed and suboptimal management is common. Effective treatment consists of behavioral and pharmacologic intervention. Use of the Dufresne Body Dysmorphic Disorder Questionnaire appears to be useful as a screening tool in an outpatient setting, and awareness of clinical features of body dysmorphic disorder in the dermatologic surgical setting may spare patients significant morbidity while allowing surgical dermatologists to manage their patients and practices more effectively.  相似文献   
149.
BACKGROUND CONTEXT: Although plate fixation enhances the fusion rate in multilevel anterior cervical discectomy and fusion (ACDF), debate exists regarding the efficacy of nonplating to rigid plate fixation in one-level ACDF. PURPOSE: To determine the efficacy of nonplating to rigid plate fixation in regards to fusion rate and clinical outcome in patients undergoing one-level ACDF with autograft. STUDY DESIGN: A review of 69 consecutive patients who underwent one-level ACDF with autograft and with or without rigid anterior cervical plate fixation. PATIENT SAMPLE: Sixty-nine patients who underwent one-level ACDF (mean age, 45 years) were evaluated for radiographic evidence of fusion (mean, 14 months) and for clinical outcome. All patients received tricortical iliac crest autografts. Disc space distraction was 2 mm, the grafts were inserted with the cortical surface positioned anteriorly, and each graft was countersunk 2 mm from the anterior vertebral border. Thirty-eight patients underwent nonplated ACDF and 31 patients underwent plated ACDF. Eighteen Orion (Sofamor-Danek, Memphis, TN), eight Atlantis (Sofamor-Danek) and five PEAK polyaxial (Depuy-Acromed, Rayham, MA) anterior cervical plating systems were used. Rigid plate fixation was used in all patients with instrumentation. Postoperatively, hard collars were worn 6 to 8 weeks in nonplated patients and soft collars were worn for 3 to 4 weeks in plated patients. Twenty-four patients were smokers (54.2% nonplating; 45.8% plating) and work-related injuries entailed 23 patients (47.8% nonplating; 52.2% plating). OUTCOME MEASURES: Fusion was assessed based on last follow-up of lateral neutral, flexion and extension radiographs. Radiographs were evaluated blindly to assess fusion and instrumentation integrity between nonplated and plated patients. Clinical outcomes were assessed with the Cervical Spine Outcomes Questionnaire and also assessed on last follow-up as excellent, good, fair or poor based on Odom's criteria. METHODS: Fusion rate and postoperative clinical outcome were assessed in 69 patients who underwent one-level ACDF with autograft and with or without rigid anterior plate fixation. Additional risk factors were also analyzed. Statistical significance was established at p<.05. RESULTS: Sixty-six patients (95.7%) achieved a solid fusion (100% nonplated; 90.3% plated). Nonunions occurred in three patients (1 smoker; 2 nonsmokers) with Orion instrumentation. Slight screw penetration into the involved and uninvolved interbody spaces occurred in one patient who was a nonsmoker and did not achieve fusion. One superficial cervical wound infection was noted in a nonplated patient. No other intraoperative or postoperative complications were noted. No statistically significant difference was noted between nonplating to rigid plating upon fusion rate (p>.05). All nonunions occurred at the C5-C6 level. Mean estimated intraoperative blood loss was significantly greater in plated patients (p=.043). Revision surgery involved 9.7% of the plated patients, whereas none of the nonplated patients required reoperation. Postoperative clinical outcome was assessed in all patients (mean, 21 months). Excellent results were noted in 18.8%, good results in 72.5% and fair results in 8.7% of the patients. Nonunion patients reported satisfactory clinical outcome. No statistical significance was noted between clinical outcome of fused and nonfused patients, the presence of a work-related injury and the use of plating (p>.05). Demographics and history of smoking were not factors influencing fusion or clinical outcome in this series (p>.05). The effect on fusion by various plate types could not be discerned from this study. CONCLUSION: A 100% and 90.3% fusion rate was obtained for one-level nonplated and plated ACDF procedures with autograft, respectively. The effects of smoking or level of fusion could not be discerned from these one-level cases. Excellent and good clinical outcome results were obtained for 91.3%. Nonplating or rigid plate fixation for ACDF in properly selected patients to treat radiculopathy with or without myelopathy has a high fusion rate and yields a satisfactory clinical outcome. Although controversy exists as to the efficacy of rigid plate fixation in one-level ACDF, solid bone fusion can be adequately obtained without plate fixation and instrumentation-related complications can be avoided. In line with the literature, plate fixation should be reserved for patients unwilling or unable to wear a hard orthosis postoperatively for an extended period of time or for those patients who seek a quicker return to normal activities. Proper patient selection, meticulous operative technique and postoperative care is essential to promote optimal graft-host incorporation.  相似文献   
150.
The purpose of this study was to compare two negative‐pressure wound healing systems (NPWT), ?75 mmHg with a silicone‐coated (SC) dressing and ?125 mmHg with polyurethane foam dressing (standard of care). In addition, this study compared the effects of two different dressing interfaces, SC dressing and gauze, with ?75 mmHg pressure. For both comparisons, two groups of five pigs were evaluated over a 21‐day time course. Two excisional wounds were made on each animal and NPWT dressings were applied. A canvas saddle was constructed to hold the NPWT device so the animal had free range of the pen. Dressings were changed twice a week and wound measurements were taken. Specimens for histology and gene expression analyses were taken on day 7 and 21. These data show that there is increased expression in a few genes associated with remodeling and inflammatory processes in the NPWT‐125 with polyurethane foam as compared with the NPWT‐75 with SC dressing. These two systems, however, are equivalent with respect to wound healing, histology, and gene expression over 21 days of healing. Further, we demonstrate that there is no difference in measure of healing between the SC dressing and a basic gauze dressing.  相似文献   
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