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11.
Sixty-two patients with lymphoedema of the arm after mastectomy and with hypertrophy of the adipose tissue were consecutively treated by liposuction in three different ways. The first group was operated on without the use of a tourniquet. In the second group, liposuction extended up to the distal edge of the tourniquet, and then into the proximal upper arm previously covered by the tourniquet using the ‘dry’ technique. Treatment of the third group was identical to that of the second one, but the area covered by the tourniquet was treated by the tumescent technique. Eighteen patients who did not have lymphoedema either treated or not treated with adrenaline served as a reference group to see how blood transfusions varied with various volumes of aspirate. Using a tourniquet significantly reduced blood loss and the number of transfusions, which was further reduced by tumescence. In the historical reference group, the number of blood transfusions increased as the volume of aspirate increased, and further if no adrenaline was added.  相似文献   
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Background and Objectives:

Limited data are available comparing epidural and patient-controlled analgesia in site-specific colorectal surgery. The aim of this study was to evaluate 2 modes of analgesia in patients undergoing laparoscopic right colectomy (RC) and low anterior resection (LAR).

Methods:

Prospectively collected data on 433 patients undergoing laparoscopic or laparoscopic-assisted colon surgery at a single institution were retrospectively reviewed from March 2004 to February 2009. Patients were divided into groups undergoing RC (n = 175) and LAR (n = 258). These groups were evaluated by use of analgesia: epidural analgesia, “patient-controlled analgesia” alone, and a combination of both. Demographic and perioperative outcomes were compared.

Results:

Epidural analgesia was associated with a faster return of bowel function, by 1 day (P < .001), in patients who underwent LAR but not in the RC group. Delayed return of bowel function was associated with increased operative time in the LAR group (P = .05), patients with diabetes who underwent RC (P = .037), and patients after RC with combined analgesia (P = .011). Mean visual analogue scale pain scores were significantly lower with epidural analgesia compared with patient-controlled analgesia in both LAR and RC groups (P < .001).

Conclusion:

Epidural analgesia was associated with a faster return of bowel function in the laparoscopic LAR group but not the RC group. Epidural analgesia was superior to patient-controlled analgesia in controlling postoperative pain but was inadequate in 28% of patients and needed the addition of patient-controlled analgesia.  相似文献   
15.
Chromanol 293B and dofetilide are inhibitors of IKs and IKr, i.e., of the slow and the rapid component of the delayed rectifier potassium current. The specificity of these drugs was tested by investigating their effects on the delayed rectifier potassium current in vascular smooth muscle, regulating the tone of blood vessels. Using depolarizing step protocols with asymmetrical potassium concentrations (135/4.5 mM K+ in pipette/bath), voltage-dependent K+ currents (IKv) of enzymatically dispersed guinea pig portal vein cells were studied in the whole-cell patch-clamp technique. Peak currents were obtained within 20 ms (at +50 mV) after activation. During a 10 s test pulse to +60 mV, these currents exhibited a relatively fast inactivation with time constants of 384 ms (τfast) and 4505 ms (τslow). Dofetilide was totally ineffective in modulating currents; in contrast, after application of chromanol 293B, a steady-state block of IKv developed within 135 s. The block was concentration-dependent with an IC50 of 7.4 μM. Chromanol did not produce any shift in the normalized steady-state activation and inactivation curves and the recovery from inactivation was not significantly changed. Chromanol 293B similarly inhibited delayed rectifier K+ channels whether in their closed or open state, and produced an “apparent” acceleration of inactivation, i.e., the drug accelerated the faster time constant of inactivation during a 10 s test pulse from 384 ms (control) to 149 ms (100 μM chromanol). In recent studies, chromanol was described as a specific blocker of slowly activating delayed rectifier potassium channels (IKs) in cardiomyocytes. The results of this study, however, extend the inhibitory spectrum of the drug and demonstrate block of closed and open state delayed rectifier K+ currents in portal vein vascular smooth muscle. Such a block could possibly contribute to the generation of portal hypertension. Received: 2 March 2001, Returned for 1. revision: 22 March 2001, 1. Revision received: 9 May 2001, Returned for 2. revision: 16 May 2001, 2. Revision received: 3 August 2001, Accepted: 20 August 2001  相似文献   
16.

Background

The aim of this study was to evaluate the efficacy of a compression anastomosis clip (CAC) for gastrojejunostomy and comparison of a novel technique with a hand-sewn anastomosis.

Methods

Sixty-six patients underwent gastrojejunostomy with the CAC or hand-sewn anastomosis. The time of bowel function recovery, the duration of nasogastric drainage, the time of initiation of oral feeding, the duration of postoperative hospital stay, the time needed to expel the clip, and the observation of any complications were recorded.

Results

Neither group had anastomotic complications such as leakage or obstruction. Anastomosis time was shorter in the CAC group than in the control group (P < 0.01). The mean time of clip expulsion was 15.1 ± 6.04 d. There was no statistical difference in postoperative results between the two groups. There was a moderate positive correlation between the day of first bowel movement and the day of clip expulsion (r = 0.536) and a strong correlation between the duration of nasogastric drainage and the day of clip expulsion (r = 0.881).

Conclusions

The method of using a CAC appeared to be safe, easy, inexpensive, and less time consuming. It should be taken into consideration that intra-abdominal complications may cause delayed CAC expulsion.  相似文献   
17.
BACKGROUND: Intravenous glycoprotein GP IIb/IIIa receptor antagonists administered to patients with acute coronary syndromes limit platelet-dependent thrombus formation and vasoconstriction and lower the complication rate of PCI. The efficacy of glycoprotein IIb/IIIa inhibitors critically depends on appropriate suppression of platelet aggregation. A growing body of evidence indicates that regimen of tirofiban used in several recent trials may be suboptimal. We investigated if a novel regimen of dosage of tirofiban administered to patients with acute myocardial infarction with ST elevation (STEMI) before primary angioplasty is safe, feasible and whether such treatment improves coronary flow in infarct-related artery. METHODS: It was an open-label, non-randomized, prospective observational study. 253 consecutive patients with STEMI, qualified to PCI were included. 104 of patients (group 1) received heparin plus tirofiban at a novel regimen (10 microg/kg bolus, followed by 0.4 microg/kg/min for 30 min and then 0.1 microg/kg/min for 12-24 hours) and the remaining 149 of the patients (group 2) received a standard dose of heparin prior to PCI. Bleeding complications were recorded. The primary end point of the study was combined TIMI 1 + 2 + 3 grade flow at the time of first contrast medium injection during angiography for primary PCI. RESULTS: Heparin was administered 50.3 +/- 58.1 minutes (group 1) or 62.3 +/- 67.3 minutes (group 2) ( p = 0.205). Tirofiban was administered for an average of 14.5 +/- 14.4 minutes before TIMI assessment (group 1). In patients treated with heparin + tirofiban the rate of combined TIMI 1 + 2 + 3 coronary flow was higher (38.4% vs. 24.8%, p = 0.020) as compared to patients treated with heparin alone. The difference in the rate of TIMI > or = 2 coronary blood flow between the groups 1 and 2 (24.0% vs. 20.1%) has not reached statistical significance ( p = 0.459). At the same time the significant difference in the rate of TIMI 1 coronary blood flow between the groups 1 and 2 was noted (14.4 vs. 4.7%, p = 0.007). In hospital mortality in the groups 1 and 2 was similar (5.3 vs. 4.8%, p = 0.838). Significant difference was noted between the groups 1 and 2 with regard to minor bleeding complications (17.3 vs. 8.7%, p = 0.041). CONCLUSION: In patients undergoing primary angioplasty for acute myocardial infarction the novel regimen of tirofiban is well tolerated and feasible, and is associated with improvement in coronary blood flow in the infarct related artery. Larger studies assessing the effects of tirofiban on clinical outcomes of patients with AMI undergoing primary angioplasty seem worthwhile.  相似文献   
18.
Two Zn(ii) complexes, K1 and K2, obtained from the template reaction of zinc(ii) acetate dihydrate with o-phenylenediamine and 2-hydroxy-5-methylisophthalaldehyde (K1) or 2-hydroxy-5-tert-butyl-1,3-benzenedicarboxaldehyde (K2), respectively, were characterized by X-ray crystallography, spectroscopic (UV-vis, fluorescence and IR), and thermal methods. In the complex [Zn2(MeO)1.4(OH)0.6(L1)]·2H2O K1, there are two binding sites in the macrocyclic ligand and they are occupied by zinc(ii) cations found in slightly distorted square pyramidal environment. The zinc(ii) cations are connected by slightly asymmetric oxo bridges with a Zn1–O14–Zn1[−x, −y + 1, −z + 1] angle of 104.8(2)°. In the dimer [Zn2(CH3COO)2(L2)]·2EtOH K2, there are two crystallographically independent binding sites both occupied by zinc(ii) cations. There is a significant difference between both complexes, since in K1 only one site is independent and the second is occupied due to the application of symmetry rules, and the geometry of both sites is identical. Thin layers of the obtained Zn(ii) complexes were deposited on Si(111) by the spin coating method and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), fluorescence spectroscopy and ellipsometry. In the non-absorbing range, the value of the refractive index exhibits normal dispersion between 1.8 and 2.1 for K1_1–K1_3; and between 2.3 and 2.6 for the K2 series of samples established for long wavelengths (longer than 500 nm). The Zn(ii) complexes and their thin layers exhibited fluorescence between 534–573 nm and 495–572 nm for the compounds and the layers, respectively. The highest quantum yield of fluorescence was achieved for K2 in benzene and in the solid state ϕ = 0.78 and 0.58, respectively. The influence of the solvent polarity on the fluorescence properties of the obtained complexes was studied. Additionally, DFT calculations were performed to explain the structures and electronic spectral properties of the complexes.

Tin fluorescent materials were obtained using a spin coating method.  相似文献   
19.
Senescence of vascular smooth muscle cells (VSMCs) contributes to aging as well as age-related diseases of the cardiovascular system. Senescent VSMCs have been shown to be present in atherosclerotic plaques. Both replicative (RS) and stress-induced premature senescence (SIPS) accompany cardiovascular diseases. We aimed to establish the signature of RS and SIPS of VSMCs, induced by a common anticancer drug, doxorubicin, and to discover the so far undisclosed features of senescent cells that are potentially harmful to the organism. Most of the senescence hallmarks were common for both RS and SIPS; however, some differences were observed. 32 % of doxorubicin-treated cells were arrested in the G2/M phase of the cell cycle, while 73 % of replicatively senescing cells were arrested in the G1 phase. Moreover, on the basis of alkaline phosphatase activity measurements, we show that a 7-day treatment with doxorubicin (dox), does not cause precocious cell calcification, which is a characteristic feature of RS. We did not observe calcification even though after 7 days of dox-treatment many other markers characteristic for senescent cells were present. It can suggest that dox-induced SIPS does not accelerate the mineralization of vessels. We consider that detailed characterization of the two types of cellular senescence can be useful in in vitro studies of potential anti-aging factors.  相似文献   
20.
The aim of this study was to evaluate the relationship between tumorigenicity of cell sublines derived from weakly tumorigenic SKv-e and SKv-I keratinocytes harboring human papillomavirus type 16 (HPV 16) and their susceptibility to autocrine growth limitation mediated by tumor necrosis factor-α (TNF-α). These sublines displayed different in vitro proliferative potential which correlated with tumorigenicity in nu/nu mice. Recombinant TNF-α inhibited in vitro growth of weakly tumorigenic parental SKv cell lines while it did not affect proliferation of their respective highly tumorigenic sublines. Resistance to TNF-α correlated with both increased in vitro proliferation and tumorigenicity. Anti-TNF-α antibodies (Ab) significantly increased in vitro proliferation of weakly tumorigenic parental SKv cells up to the levels of their highly tumorigenic sublines. Growth of highly tumorigenic SKv cells was not affected. On the other hand, proliferation of SKv cells was affected neither by transforming growth factor-β (TGF-β) nor by anti-TGF-β Ab. All SKv cell sublines tested spontaneously released TNF-α, as evaluated by a specific radioimmunoassay; however, the levels of the endogenous cytokine were not related to their proliferative potential and tumorigenicity. An increased resistance to the anti-proliferative effect of TNF-α may be associated with decreased expression of TNF-α receptors (TNF-αR) inasmuch as evaluation of 125 I-TNF-α binding and Northern-blot analysis of TNF-αR-specific mRNA showed that highly tumorigenic SKv cell sublines expressed significantly lower numbers of TNF-αR than their respective parental cells. These results show that an increased tumorigenicity of HPV 16-harboring SKv keratinocytes may be, at least partially, due to escape from autocrine TNF-α-mediated growth limitation.  相似文献   
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