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11.
The double-staple technique in colorectal anastomoses: a critical review.   总被引:3,自引:0,他引:3  
The widespread availability and use of stapling devices have changed colorectal surgery. In 1980, Knight and Griffen developed the "double-staple" technique, using a circular stapler to transect a linear rectal staple line. This eliminated the need for a hand-sewn, distal purse string, which was sometimes difficult or even impossible to accurately place low in the pelvis. To evaluate this procedure, the authors have reviewed their results with the double-staple technique over the past 5 years. One hundred four patients underwent this procedure between 1985 and 1990 at Thomas Jefferson University Hospital (Philadelphia, PA). There were 60 men and 44 women, with a mean age of 62.4 years. Seventy-two patients underwent operation for carcinoma of the rectum or sigmoid. Thirty-five of these had preoperative radiation therapy. Other diagnoses included 1) diverticular disease, 2) rectal prolapse, 3) villous adenoma, 4) endometrial carcinoma, 5) fistula, 6) stricture, 7) Crohn's disease, 8) colonic endometriosis, 9) lymphoma, 10) ovarian carcinoma, and 11) ulcerative colitis. Incomplete "donuts" were observed in 5 patients. Diverting colostomies were performed in 23 patients, ileostomies in 3. Postoperative complications relating to the double-staple technique itself included a rectovaginal fistula in 1 patient. There were 3 clinical leaks (2.8%), all treated nonoperatively. No strictures were observed. As previously observed, the authors believe the double-staple technique offers certain advantages over traditional, hand-sewn and stapled anastomoses, for instance: 1) there is significantly less contamination, 2) the anastomosis is technically easier, and 3) bowel segments of different diameters can be easily anastomosed.  相似文献   
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The central action of the potential antidepressant drug pizotifen (Sandomigran) was studied in mice, rats and rabbits. Pizotifen in doses up to 10 mg/kg i.p. was ineffective in classic tests for antidepressant activity. It neither antagonized the effects of reserpine in rats (hypothermia, ptosis) nor potentiated the effects of amphetamine (in mice and rats), nialamide or L-dopa (in mice) on locomotor activity. However, its antidepressant activity was found in the despair test in rats.On the other hand, pizotifen inhibited the head twitch reaction induced by L-5-hydroxytryptophan in mice (ED50=0.009 mg/kg, i.p.) and by 5-methoxytryptamine (+tranylcypromine) in rats (ED50=0.45 mg/kg, i.p.). It also antagonized tryptamine-induced clonic convulsions of fore-paws in rats (ED50=0.35 mg/kg, i.p.), and in doses of 5–10 mg/kg s.c. inhibited hyperthermia produced by LSD in rabbits. Finally, pizotifen (0.1–0.3 mg/kg, i.v.) inhibited or abolished LSD- or quipazine-induced stimulation of the hind limb flexor reflex of spinal rats; the above effect was not due to noradrenolytic action of the drug. These results suggest that pizotifen strongly blocks the central postsynaptic serotonin receptors.  相似文献   
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Background Numerous studies have demonstrated increased cardiovascular risk in psoriasis. Circulating endothelial cells (CECs) have been proposed as a new marker of endothelial dysfunction that plays an important role in pathogenesis of atherosclerosis. Objective The aim of this study was to compare the number of CECs in psoriatic patients to a control group and to analyze possible correlations between the numbers of CECs and the plasma levels of classical markers of endothelial dysfunction, such as: sICAM‐1, sE‐selectin and von Willebrand factor (vWF). Methods The number of CECs, identified as CD146 + / CD45‐ cells, were determined in peripheral blood with using flow cytometry in psoriatic patients (n = 63) and controls (n = 31). The plasma levels of: sICAM‐1, sE‐selectin, vWF were measured with ELISA. The severity of psoriasis was assessed with PASI. Results The number of CECs was significantly increased in psoriatic patients compared with controls (P < 0.00001) and positively correlated with disease severity (R = 0.360; P = 0.0037). The levels of sICAM‐1, sE‐selectin and vWF were significantly elevated in psoriatic patients (P < 0.00001; P < 0.00001; P = 0.00072, respectively). The number of CECs was significantly, positively correlated with the levels of sICAM‐1 (R = 0.393; P = 0.0014) and vWF (R = 0.314; P = 0.012) in psoriatic patients. The levels of sICAM‐1 and sE‐selectin were positively correlated with disease severity (R = 0.356; P = 0.0041 and R = 0.407; P = 0.0009, respectively). Conclusion The increased number of CECs that correlates with disease severity and plasma levels of sICAM‐1 and vWF may indicate endothelial dysfunction or injury in patients with psoriasis.  相似文献   
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We report the synthesis of an amphiphilic polysaccharide, a phospholipid (1,2-dioleoyl-sn-glycero-phosphoetilamine, DOPE) conjugated with the anionic xanthan gum, and its ability to spontaneously self-assemble under mild aqueous conditions. This work also aimed to apply a microfluidic platform that can precisely fabricate microsized and monodispersed capsules for cell encapsulation. Stable hollow capsular structures were obtained by the generation of homogeneous spherical droplets of the self-assembled polymer in the microfluidic device through the formation of a water-in-oil emulsion, followed by the stabilization of the polymer aggregates in a separate collection vessel containing phosphate-buffered saline (physiological ionic strength and pH). The properties (size, morphology, permeability) and performance (stability) of the obtained microcapsules were studied, as well their ability to support the viability, function and proliferation of encapsulated cells. ATDC5 cells were encapsulated within the capsules and shown to remain viable, evidencing increased cellular metabolic activity over 21 days of in vitro culture. By combining microfluidic droplet generation and self-assembly of xanthan–DOPE, we were able to fabricate microcapsules that provided an adequate environment for cells to survive and proliferate.  相似文献   
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Cancer is a major worldwide health problem and one of the leading causes of death either in developed or developing countries. Plant extracts and derivatives have always been used for various disease treatments and many anticancer agents issued from plants and vegetables are clinically recognized and used all over the world. Lycium europaeum (Solanaceae) also called “wolfberry” was known since ancient times in the Mediterranean area as a medicinal plant and used in several traditional remedies. The Lycium species capacity of reducing the incidence of cancer and also of halting or reserving the growth of cancer was reported by traditional healers. In this study, the antiproliferative capacity, protective properties, and antioxidant activity of the hydro-alcoholic fruit extract of Lycium europaeum were investigated. Results showed that Lycium extract exhibits the ability to reduce cancer cell viability, inhibits proliferation, and induces apoptosis in A549 human lung cancer cells and PC12 rat adrenal medulla cancer cells, in a concentration- and time-dependent manner. Cytotoxic effect on normal rat cerebellum granule cells was assessed to be nonsignificant. Results also showed that Lycium fruit extract protected lipids, proteins, and DNA against oxidative stress damages induced by H2O2 via scavenging reactive oxygen species.  相似文献   
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Background: Previous studies have demonstrated an increased risk for cardiovascular events and pulmonary disease in patients with biomass fuel exposure (BFE). However, biventricular heart function has yet to be investigated in these patients. Left ventricular (LV) myocardial performance index (LVMPI), which is an index of global ventricular function, incorporates ejection, isovolumic relaxation, and contraction times. In this study, pulmonary function and biventricular heart function were investigated in nonsmoking female patients with BFE. Methods: Our study population consisted of 46 female patients with BFE (group 1) and 31 control subjects (group 2). Pulmonary function tests and transthoracic echocardiographic examination were performed. Right ventricular myocardial performance index (RVMPI) and LVMPI were obtained by tissue Doppler imaging echocardiography (TDI). Results: BFE caused obstructive and restrictive spirometric impairments. RVMPI was higher in group 1 (0.55 ± 0.07) than group 2 (0.46 ± 0.06) (P = 0.042) and LVMPI was higher in group 1 (0.54 ± 0.08) than group 2 (0.47 ± 0.05) (P = 0.032). Also, pulmonary artery systolic pressure was higher in group 1 than group 2 (P = 0.02). Conclusions: BFE causes both obstructive and/or restrictive lung disease and systolic and diastolic biventricular dysfunction. Nonetheless, long‐term studies are needed to understand on BFE‐related ventricular dysfunctions and to document subsequent cardiovascular events. (Echocardiography 2011;28:52‐61)  相似文献   
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