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991.
Systemic stress response after laparoscopic and open gastric bypass   总被引:9,自引:0,他引:9  
BACKGROUND: The magnitude of the systemic stress response is proportional to the degree of operative trauma. We hypothesized that laparoscopic gastric bypass (GBP) is associated with reduced operative trauma compared with open GBP, resulting in a lower systemic stress response. STUDY DESIGN: Forty-eight patients with a body mass index of 40 to 60 were randomly assigned to laparoscopic (n = 26) or open (n = 22) GBP Blood samples were measured at baseline and at 1, 24, 48, and 72 hours postoperatively. Metabolic (insulin, glucose, epinephrine, norepinephrine, dopamine, ACTH, cortisol), acute phase (C-reactive protein), and cytokine (interleukin [IL]-6, IL-8, tumor necrosis factor [TNF]-alpha) responses were measured. Catabolic response was also measured by calculating the nitrogen balance at 24 and 48 hours postoperatively. RESULTS: The two groups of patients were similar in terms of age, gender, and preoperative body mass index. The mean operative time was longer for laparoscopic GBP than for open GBP (229 +/- 50 versus 207 43 minutes). After laparoscopic and open GBP, plasma concentrations of insulin, glucose, epinephrine, dopamine, and cortisol increased; IL-8 and TNF-alpha remained unchanged; and negative nitrogen balances occurred at 24 and 48 hours. There was no significant difference in these parameters between groups. Concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 levels also increased, but these levels were significantly lower after laparoscopic GBP than after open GBP (p < 0.05). CONCLUSIONS: Systemic stress response after laparoscopic GBP is similar to that after open GBP, except that concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 are lower after laparoscopic than after open GBP. These findings may suggest a lower degree of operative injury after laparoscopic GBP.  相似文献   
992.
BACKGROUND: The Program on the Surgical Control of the Hyperlipidemias (POSCH), a secondary intervention trial, was the only lipid/atherosclerosis randomized clinical trial that used a surgical modality--partial ileal bypass. POSCH provided solid evidence for the clinical and arteriographic benefits of lipid profile normalization. Few longterm followup reports have been published in this field. This report concerns overall mortality, the primary endpoint of POSCH, with a mean followup of 18 years (range 15.5 to 23.0 years). STUDY DESIGN: Overall mortality data were compiled from reports to the POSCH clinics, followup telephone calls, death certificates, and the US National Death Index. RESULTS: There were 144 deaths in the control group (n = 417) and 120 deaths in the intervention group (n = 421), using intent-to-treat analysis. The risk reduction in the intervention group was 0.201 (20%); the risk ratio was 0.799, or 0.8 (95% confidence intervals, 0.628 to 1.018, p = 0.07). The proportion of patients alive was 65.7% in the control group and 72.0% in the intervention group, for a difference of 6.3% in the intervention group (p = 0.05). Kaplan-Meier survival analysis (p = 0.046) and disease-free intervals analysis at 70% survival (p < 0.001) were confirmatory. The gain in life expectancy in the intervention group was 2.7 years. CONCLUSIONS: Longterm followup POSCH data demonstrate that lipid profile normalization will decrease overall mortality and will maintain a persistent and constant increase in life expectancy.  相似文献   
993.
994.
Herpes simplex virus (HSV) infection can be devastating in the neonate. The disease most commonly presents as 1 of 3 clinical manifestations: disseminated visceral infection (with and without central nervous system involvement), isolated meningoencephalitis, and infection limited to the skin, eyes, and/or mucous membranes (SEM). Exposure leading to neonatal infection typically occurs as peripartum vertical transmission, most typically by direct contact with urogenital lesions or infected genital secretions, or as an ascending infection exploiting disrupted chorioamniotic membranes. We present a novel case of a newborn girl who developed HSV-2 keratoconjunctivitis despite being delivered via an elective, uncomplicated, repeat cesarean over intact chorioamniotic membranes in the absence of active clinical maternal HSV infection and despite having a negative medical history of previous orolabial or genital herpetic infection.  相似文献   
995.
Receptor supersensitivity is an important concept for understanding neurotransmitter and receptor dynamics. Traditionally, detection of receptor supersensitivity has been performed using autoradiography or positron emission tomography (PET). We show that use of magnetic resonance imaging (MRI) not only enables one to detect dopaminergic supersensitivity, but that the hemodynamic time course reflective of this fact is different in different brain regions. In rats unilaterally lesioned with intranigral 6-hydroxydopamine, apomorphine injections lead to a large increase in hemodynamic response (cerebral blood volume, CBV) in the striato-thalamo-cortico circuit on the lesioned side but had little effect on the intact side. Amphetamine injections lead to increases in hemodynamic responses on the intact side and little on the lesioned side in the same animals. The time course for the increase in CBV after either amphetamine or apomorphine administration was longer in striatum and thalamus than in frontal cortex. (11)C-PET studies of ligands which bind to the dopamine transporter (2-beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane 1, 5-naphthalnendisulfonate, WIN 35, 428 or CFT) and D2 receptors (raclopride) confirm that there is a loss of presynaptic dopamine terminals as well as upregulation of D2 receptors in striatum in these same animals. Pharmacologic MRI should become a sensitive tool to measure functional supersensitivity in humans, providing a complementary picture to that generated using PET studies of direct receptor binding.  相似文献   
996.
997.
Background Long-term refractive and visual outcome after penetrating keratoplasty (PK) only and the triple procedure in eyes with Fuchs' endothelial dystrophy were assessed and compared.Design Retrospective, non-randomized, cross-sectional, clinical, single-centre study.Methods Ninety-two eyes of 87 patients were divided into two groups. Group 1 consisted of 28 eyes (mean age 62±13 years) that had undergone PK only and group 2 consisted of 64 eyes (mean age 69±10 years) that had undergone the triple procedure. Inclusion criteria were: (1) Fuchs' dystrophy, (2) central nonmechanical trephination, (3) double-running suturing technique and (4) availability of ‘two-sutures-out’ findings.In all eyes, a central trephination was performed (donor trephination from the epithelial side) using the 193-nm excimer laser along metal masks with eight ‘orientation teeth/notches’. A double-running 10–0 nylon suture was applied in all eyes. Subjective refractometry (trial glasses), standard keratometry (Zeiss) and corneal topography analysis (TMS-1, Tomey) were performed in all eyes with ‘two-sutures-in’, ‘one-suture-out’, and ‘two-sutures-out’. Main outcome measures included refractive cylinder, keratometric and topographic net astigmatism, keratometric and topographic central power, best-corrected visual acuity (BCVA), spherical equivalent (SE) of manifest refraction, surface regularity index (SRI), surface asymmetry index (SAI), and regularity of keratometry mires.Results The results were compared between the two groups (i.e. group 1 vs group 2) at various stages (i.e. ‘two-sutures-in’, ‘one-suture-out’, ‘two-sutures-out’). Refractive cylinder in dioptres [D] was 2.5/2.0/2.5 vs 2.0/1.5/3.0, keratometric astigmatism [D] was 3.5/2.6/3.0 vs 3.5/3.1/3.5 and topographic astigmatism [D] was 3.9/4.1/4.9 vs 4.2/5.0/5.1. Keratometric central power [D] was 41.7/42.4/43.8 vs 41.5/41.9/43.3 and topographic central power [D] was 42.3/43.6/43.7 vs 42.6/41.8/44.3. BCVA was 0.5/0.6/0.6 vs 0.5/0.5/0.5. SE [D] was 0.0 /0.0/–0.5 vs –0.5/–0.5/–1.1. SRI was 1.5/1.1/1.0 vs 1.4/1.4/1.2 and SAI was 1.0/0.8/1.0 vs 1.3/1.2/1.0. The proportion of ‘regular’ and ‘mildly irregular’ keratometry mires was 44% / 69% / 68% vs 29% / 46% / 66%. The differences between the two groups did not reach statistical significance at any of the stages.Conclusions Refractive and visual outcome after the triple procedure did not differ significantly from that after PK only. Therefore, we recommend the triple procedure in elderly patients with Fuchs’ dystrophy and cataract to avoid delayed visual rehabilitation and a second surgical procedure.  相似文献   
998.
PURPOSE: Accommodative insufficiency (AI) and convergence insufficiency (CI) have been associated with similar symptomology and frequently present at the same time. The severity of symptomology in CI has been linked to the severity of the CI, suggesting a dose-dependent relationship. However, with increasing severity of CI also comes increased comorbidity of AI. AI alone has been shown to cause significant symptomology. We hypothesize that AI drives the symptoms in CI with a comorbid AI condition (CIwAI) and that it is the increased coincidence of AI, rather than increased severity of CI, which causes additional symptomology. METHODS: Elementary school children (n = 299) participated in a vision screening that included tests for CI and AI and the CISS-V15 symptom survey. They were categorized into four groups:1) normal binocular vision (NBV); 2) AI-only; 3) CI-only; and 4) CIwAI. One hundred seventy elementary school children fell into the categories of interest. RESULTS: Pairwise comparison of the group means on the symptom survey showed: 1) children with AI-only (mean = 19.7, p = 0.006) and children with CIwAI (mean = 22.8, p = 0.001) had significantly higher symptom scores than children with NBV (mean = 10.3); and 2) children with CI-only (mean = 12.9, p = 0.54) had a similar symptom score to children with NBV. Using a two-factor analysis of variance (AI and CI), the AI effect was significant (AI mean = 21.56; no AI mean = 11.56, p < 0.001), whereas neither the CI effect (p = 0.16) nor the CI by AI interaction effect (p = 0.66) were significant. CONCLUSION: CI is a separate and unique clinical condition and can occur without a comorbid AI condition, our CI-only group. Past reports of high symptom scores for children with CI are the result of the presence of AI, a common comorbid condition. When AI is factored out, and children with CI only are evaluated, they are not significantly more symptomatic than children with NBV.  相似文献   
999.
Minimally invasive surgical staging for esophageal cancer   总被引:9,自引:0,他引:9  
Background: The incidence of esophageal adenocarcinoma is increasing in the United States, and the 5-year survival rate is dismal. Preliminary data suggest that conventional imaging is inaccurate in staging esophageal cancer and could limit accurate assessment of new treatments. The objective of this study was to compare minimally invasive surgical staging (MIS) with conventional imaging for staging esophageal cancer. Methods: Patients with potentially resectable esophageal cancer were eligible. Staging by conventional methods used computed tomography (CT) scan of the chest and abdomen, and endoscopic ultrasound (EUS), whereas MIS used laparoscopy and videothoracoscopy. Conventional staging results were compared to those from MIS. Results: In 53 patients, the following stages were assigned by CT scan and EUS: carcinoma in situ (CIS; n= 1), I (n= 1), II (n= 23), III (n= 20), IV (n= 8). In 17 patients (32.1%), MIS demonstrated inaccuracies in the conventional imaging, reassigning a lower stage in 10 patients and a more advanced stage in 7 patients. Conclusions: In 32.1% of patients with esophageal cancer, MIS changed the stage originally assigned by CT scan and EUS. Therefore, MIS should be applied to evaluate the accuracy of new noninvasive imaging methods and to assess new therapies for esophageal cancer. Received: 5 April 1999/Accepted: 15 March 2000/Online publication: 12 July 2000  相似文献   
1000.
BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (GBP) has been previously described, but a comparative study between laparoscopic and open GBP has not been reported. The purpose of this study was to compare surgical outcomes oflaparoscopic GBP with those of open GBP for treatment of morbid obesity. STUDY DESIGN: From August 1998 to September 1999, we prospectively collected outcome data on 35 patients with body-mass indices between 40 kg/m2 and 60 kg/m2 who underwent laparoscopic GBP. Demographics, operative data, perioperative complications, and weight losses were collected and compared with those obtained from a retrospective chart review of 35 patients with body-mass indices between 40 kg/m2 and 60 kg/m2 who underwent open GBP before August 1998. RESULTS: Age, gender, preoperative body-mass index, preoperative comorbidity, and earlier abdominal surgery were similar in both groups. All laparoscopic operations were completed without conversion to laparotomy. Mean operative time, operative blood loss, length of intensive care stay, and length of hospital stay were significantly less after laparoscopic GBP than after open GBP (p<0.05). There was no 30-day mortality in either group. At 1-year followup, analysis of the percentage of excess body weight loss showed no significant difference between the two groups (p<0.05). CONCLUSIONS: Laparoscopic Roux-en-Y gastric bypass is technically feasible and safe. Laparoscopic GBP confers the clinical benefits of laparoscopy and an initial weight loss similar to that of open GBP.  相似文献   
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