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741.
OBJECTIVE: Acid secretion produced by a heterotopic gastric mucosal patch (HGMP) in the proximal esophagus, instead of gastric acid, may be responsible for laryngopharyngeal reflux (LPR), passing the upper esophageal sphincter. The aim of this study was to investigate the prevalence of HGMP in the proximal esophagus in patients with posterior laryngitis indicating the presence of LPR in comparison with a control group and to elucidate the possible role of this lesion in the pathogenesis of LPR. MATERIAL AND METHODS: A total of 36 consecutive patients with posterior laryngitis diagnosed on laryngoscopic examination were enrolled in the study. Esophagoscopy and ambulatory 24-h intra-esophageal dual-probe pH monitoring were performed in all patients. During endoscopy, special attention was paid to the proximal part of the esophagus, and the proximal electrode for pH monitoring was placed in this region under endoscopic view. The control group comprised 660 consecutive patients who had undergone upper gastrointestinal endoscopy for the usual indications. When HGMP was found, biopsies were taken for histological confirmation. RESULTS: HGMP was detected in 5 out of 36 patients. One out of five patients with patches was excluded from the study because the histopathology of this patient's patch revealed antral-type mucosa, which is not capable of acid secretion. Thus a total of 35 patients were included in the study, yielding a HGMP prevalence of 11.4% (4/35). Compared with the prevalence of the control group (1.6%), a significant difference was observed (p<0.005). pH monitoring showed that 45.4% of the patients had abnormal proximal acid reflux. All of four HGMP (+) patients with posterior laryngitis revealed significantly higher abnormal proximal reflux compared to the patients without patches (p<0.05). CONCLUSIONS: This first preliminary study may suggest that HGMP in the cervical esophagus could play a role in the pathogenesis of LPR, at least in a minor group of patients with posterior laryngitis, depending on its capability to produce acid in situ, although isolated proximal reflux could not be demonstrated. This finding may need to be supported by further studies with larger patient populations and using acid stimulation tests.  相似文献   
742.
Isolated case reports in which symptomatic hearing loss develops suddenly during the course of inflammatory bowel disease (IBD) have been reported, but the presence of subclinical sensorineural hearing loss (SNHL) associated with IBD has been investigated in only two preliminary studies.In order to research this further, we aimed to investigate the presence of subclinical SNHL in IBD by comparison with a control group and to examine possible relations between the bowel disease parameters and hearing loss.Otoscopy, tympanometry, and pure tone audiometry were carried out in 39 patients with IBD (21 Crohn's disease [CD], 18 ulcerative colitis [UC]) and 25 healthy age- and sex-matched controls. All patients and control subjects had normal otoscopy findings and tympanometry was unremarkable, excluding middle ear disease and conductive hearing loss. Analysis of each frequency examined showed that the average hearing thresholds were increased significantly in the study group compared to those of the control group at higher frequencies (2, 4, and 8 kHz). When these parameters were compared with the control group according to subgroups of IBD, a significant difference was determined for the UC group at frequencies of 2, 4, and 8 kHz and for the CD group only at the frequency of 4 kHz. Although there was a trend of increment in SNHL as the age of the patient and duration and extent of UC increased, no significant correlation was observed between SNHL and these parameters or sex, activity, involvement site, medication history of IBD, and coexistence of other extraintestinal manifestations. In conclusion, it was demonstrated that a subclinical SNHL may be associated with UC and somewhat with CD, affecting mainly the high frequencies. In light of this finding, it may be advisable to investigate labyrinth functions as well as other extraintestinal manifestations in patients with IBD. This article was presented at the 12th United European Gastroenterology Week, 2004, in Prague, Czech Republic.  相似文献   
743.
BACKGROUND: The purpose of this study was to determine if protocol-driven normoglycemic management in trauma patients affected glucose control, ventilator-associated pneumonia, surgical-site infection, and inpatient mortality. METHODS: A prospective, consecutive-series, historically controlled study design evaluated protocol-driven normoglycemic management among trauma patients at Vanderbilt University Medical Center. Those mechanically ventilated > or =24 hours and > or =15 years of age were included. A glycemic-control protocol required insulin infusion therapy for glucose >110 mg/dL. Control patients included those who met criteria, were admitted the year preceding protocol implementation, and had hyperglycemia treated at the physician's discretion. RESULTS: Eight hundred eighteen patients met study criteria; 383 were managed without protocol; 435 underwent protocol. The protocol group had lower glucose levels 7 of 14 days measured. After admission, both groups had mean daily glucose levels <150 mg/dL. No difference in pneumonia (31.6% vs 34.5%; p = .413), surgical infection (5.0% vs 5.7%; p = .645) or mortality (12.3% vs 13.1%; p = .722) occurred between groups. If one episode of blood glucose level was > or =150 mg/dL (n = 638; 78.0%), outcomes were worse: higher daily glucose levels for 14 days after admission (p < .001), pneumonia rates (35.9% vs 23.3%; p = .002), and mortality (14.6% vs 6.1%; p = .002). One or more days of glucose > or =150 mg/dL had a 2- to 3-fold increase in the odds of death. Protocol use in these patients was not associated with outcome improvement. CONCLUSIONS: Protocol-driven management decreased glucose levels 7 of 14 days after admission without outcome change. One or more glucose levels > or =150 mg/dL were associated with worse outcome.  相似文献   
744.
We report the clinicopathologic features of 24 uterine primary and metastatic endometrial stromal sarcomas with fibromyxoid features (ESS-F) and smooth muscle differentiation (ESS-SM) (endometrial stromal sarcoma variants). Two groups of tumors were retrieved from the surgical pathology files at Memorial Sloan-Kettering Cancer Center: 1) gynecologic mesenchymal neoplasms with striking smooth muscle or fibroblastic differentiation that did not meet the clinical or histologic criteria for leiomyosarcoma or other established neoplasms containing smooth muscle; and 2) metastatic lesions showing ovoid and spindle cell morphology, involving lung, originally diagnosed as low-grade leiomyosarcoma, low-grade smooth muscle neoplasm, intravenous leiomyomatosis, fibrous hamartoma, and benign metastasizing leiomyoma. We identified 12 patients with 30 tumors; 24 were available for review. The mean age was 51 years (range 21-74 years). Follow-up >1 year was available for eight patients, with a mean time of 8.5 years. Each patient had a uterine primary and 10 experienced metastases. Mean time to recurrence was 6.8 years. Sites of metastasis included lung, retroperitoneum, right atrium/inferior vena cava, colon, and ovaries. No patient died of disease, but in many cases the follow-up period ended with the discovery of a metastasis. Four patients were originally diagnosed with endometrial stromal sarcoma, but other presenting diagnoses included benign metastasizing leiomyoma, fibroleiomyomatous tumor of lung, smooth muscle tumor of uncertain or low malignant potential, and intravascular leiomyomatosis. On review each patient had at least one tumor (primary and/or metastasis) that was determined to be an endometrial stromal sarcoma variant. Review diagnoses were as follows: endometrial stromal sarcoma (nonvariant), ESS-F, and ESS-SM. Eight of 10 primary tumors with available slides were endometrial stomal sarcoma variants (six ESS-F and two ESS-SM). When these variant features were present, they comprised between 50% and 100% of the neoplasm. The variant histology tumors exhibited prominent spiral arterioles, perivascular edema, and stromal cell condensation around blood vessels. All metastases but one were variant tumors; eight were ESS-F and five were ESS-SM. Four metastases did not resemble the uterine primary. Desmin marked smooth muscle mostly but not specifically. h-Caldesmon marked smooth muscle exclusively. Endometrial stromal cells as well as some fibroblasts and smooth muscle cells expressed CD10. We conclude that the presence of even focal endometrial stromal differentiation in an invasive uterine mesenchymal lesion with a predominant low-grade smooth muscle, fibroblastic, and/or myxoid phenotype should permit classification as low-grade sarcoma-they should be considered endometrial stromal sarcomas.  相似文献   
745.
The aim of this study was to validate orthogonal polarization spectral (OPS) imaging against intravital fluorescence microscopy (IFM) for microvascular measurements in normal skin and during wound healing. Experiments were performed on the ears of hairless mice (N = 8). The diameter of arterioles and venules, red blood cell velocity in venules, and the functional capillary density were assessed under normal conditions using OPS imaging and IFM. After creation of a circular wound, these observations were repeated at the identical microvascular regions on days 4, 7, 10, and 15. Images were videotaped, and CapImage was used for off-line computer-assisted analysis. Using OPS imaging, the microcirculation of wounded skin in hairless mice could be observed successfully. The regression analyses against standard IFM revealed a significant (p < 0.001) correlation for measurements of all microcirculatory parameters investigated (venular diameter: r(2) = 0.98, N = 345; red blood cell velocity: r(2) = 0.51, N = 326; functional capillary density: r(2) = 0.44, N = 156). However, for diameter as well as for functional capillary density measurements, OPS imaging yielded lower absolute values compared with IFM. The authors were able to validate OPS imaging against IFM for the measurement of microvascular parameters in an animal model of skin wound healing. Such a device should now help to study the role of microcirculation in physiology and pathophysiology during wound healing in patients. First clinical investigations are promising.  相似文献   
746.

Background  

Violence against females is a widespread public health problem in Turkey and the lifetime prevalence of IPV ranges between 34 and 58.7%. Health care workers (HCW) sometimes have the unique opportunity and obligation to identify, treat, and educate females who are abused. The objective of this study was to evaluate the knowledge, attitudes, and experiences of the emergency department (ED) staff regarding intimate partner violence (IPV) at a large university hospital in Turkey.  相似文献   
747.
748.
Several studies have well confirmed the contribution of oxidative stress in the pathogenesis of methotrexate (MTX)-induced damage in the small intestine. Many agents have been tried experimentally to reduce or inhibit the oxidative stress. To our knowledge, there is no study about apricot consumption on the MTX-induced damage in the small intestine. The aim of this study was to determine the possible protective effects of apricot and beta-carotene on MTX-induced intestinal damage in rats. The rats were randomly divided into seven groups as follows; I-control group; II-apricot group; III-beta-carotene group; IV-MTX group; V-apricot+MTX group; VI-beta-carotene+MTX group and VII-apricot+beta-carotene+MTX group. In the MTX group; fusion and shortening in the villus, epithelial desquamation, crypt loss, inflammatory cell infiltration in the lamina propria, goblet cell depletion and microvillar damage were observed in the small intestine. Parallel to histological results, malondialdehyde (MDA) content and myeloperoxidase (MPO) activity were found to be increased, whereas superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GP-x) activities and glutathione (GSH) content were decreased in the MTX group. However, single or combined application of apricot and beta-carotene ameliorated all of these hazordous effects in antioxidant system in MTX-treated groups. In conclusion, our results demonstrate that apricot and/or beta-carotene treatment may protect the impairment of oxidative stress and ameliorate MTX-induced intestine damage at biochemical and histological levels.  相似文献   
749.
Targeted delivery of anticancer drugs is one of the most actively pursued goals in anticancer chemotherapy. A major disadvantage of anticancer drugs is their lack of selectivity for tumour tissue, which causes severe side effects and results in low cure rates. Any strategy by which a cytotoxic drug is targeted to the tumour, thus increasing the therapeutic index of the drug, is a way of improving cancer chemotherapy and minimizing systematic toxicity. This study covers the preparation of the gelatin microsphere (GM)-anti-bovine serum albumin (anti-BSA) conjugate for the development of a drug targeting approach for anticancer drug delivery. Microspheres of 5% (w/v) gelatin content were prepared by crosslinking with glutaraldehyde (GTA) at 0.05 and 0.50% (v/v) concentration. Microspheres were in the size range of 71–141 μm. The suitability of these microspheres as drug carriers for anticancer drug delivery was investigated in vitro by studying the release profiles of loaded methotrexate (MTX) and 5-fluorouracil (5-FU) and the cytotoxicities on cancer cell lines. The in vitro MTX release profiles (~22–46% released in 24 h depending on the amount of GTA used) were much slower compared to 5-FU (~42–91% released in 24 h). Both drugs demonstrated an initial fast release, which was followed by gradual, sustained drug release. The MTT cytotoxicity test results of GMs loaded with 5-FU and MTX showed ~54–70% and ~52–67% cytotoxicities in 4 days. In general, incorporation of MTX and 5-FU in microspheres enhanced the cytotoxic effect in a more prolonged manner compared to the free drugs. Gelatin micospheres were chemically conjugated to anti-BSA and the antigen–antibody activities were studied by immunofluorescence. Results indicated ~80% binding with conjugated anti-BSA and BSA-FITC. Based on their low cytotoxicity and the high antigen binding efficiencies, anti-BSA conjugated gelatin microspheres could be suitable targeted drug carrier systems for selective and long-term delivery of anticancer drugs to a specific body compartment (i.e. bladder cancer).  相似文献   
750.
Nanosized liposomal drug delivery systems are well suited for selective drug delivery at tumor sites. Celecoxib (CLX) is a highly hydrophobic cyclooxygenase-2 inhibitor that can reduce the incidence of colorectal polyps; however, the adverse cardiovascular effects limit its applicability. Here, we report a liposomal formulation of CLX using 1,2-Distearoyl-sn-glycero-3-phosphocholine, cholesterol, and polyethylene glycol. Encapsulation efficiency of the drug was greater than 70%; the release was slow and sustained with only 12%–20% of CLX released in the first 12 h. Flow cytometry and confocal microscopy studies using the colon cancer cell lines HCT-116 and SW620 showed significantly higher cellular association and internalization of the liposomes after incubation for 6 h when compared with 30 min. The liposomes did not colocalize with transferrin, but had a punctuate appearance, indicating vesicular localization. Cell proliferation was inhibited by 95% and 78%, respectively, in SW620 and HT29 cells after incubation with 600 μM liposomal CLX for 72 h. Moreover, cellular motility, as shown by a scratch wound healing assay, was also significantly (p = 0.006) inhibited when SW620 cells were incubated with 400 μM liposomal CLX. This is the first report of the successful encapsulation of CLX in a long-circulating liposomal formulation that could be effective against colorectal cancer.  相似文献   
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