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Mechanisms by which gastroplasty for morbid obesity causes weight loss are poorly understood. We studied the role of altered gastric emptying in 50 patients before surgery, 1-4 weeks after surgery, and 2-24 months after surgery using technetium-99m pentetate in water for liquid meals and a Tc-99m styrene divinylbenzene copolymer resin in oatmeal for semisolid meals. We determined the emptying half-times of the stomach before and after surgery in the proximal and distal compartments. The proximal compartment emptied promptly in the early and late postoperative periods. The distal compartment emptied liquids at rates similar to those before surgery, while the late postoperative emptying of semisolids was significantly faster. The stoma connecting the two compartments thus permits rapid transit of liquids and semisolids without delay of distal compartment emptying. No correlation was seen between the emptying half-times or changes thereof and eventual weight loss. Delayed gastric emptying is therefore not the mechanism for satiety and weight loss after gastroplasty has been performed.  相似文献   
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OBJECTIVES: (1) To compare two stool antigen EIAs (HpSA, FemtoLab) and PCR of ureaseA and cagA in feces, with (13)C-urea breath test (UBT). (2) To ascertain whether a simplified UBT (breath collection time = 10 min) is as reliable as the standard assay (30 min). DESIGN AND METHODS: Helicobacter pylori status was recorded in Group 1 (n = 187) by UBT, H. pylori stool antigen, ureA and cagA PCR in feces. UBT with 10, 20 and 30 min sampling was performed in Group 2 patients (n = 283). RESULTS: The sensitivity and specificity of HpSA, FemtoLab, and ureA were 67% and 99%, 90% and 96%, 35% and 98%, respectively. cagA results were positive in 16/48 H. pylori-positive, and in 5/100 H. pylori-negative patients. The results of UBT with a 10- and 30-min sampling strictly overlapped. CONCLUSION: UBT with 10 min breath collection and FemtoLab stool antigen assay are the most reliable non-invasive tests to diagnose H. pylori infection.  相似文献   
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Several experimental studies have suggested that specific nutrients might play a role on the risk of liver damage. Nevertheless, few epidemiological studies have evaluated the role of diet on the risk of symptomatic liver cirrhosis, giving contradictory results. To evaluate the role of the intake of nutritional factors and dietary patterns on the risk of symptomatic liver cirrhosis and to examine their combined action with alcohol consumption we used data from the Italian Study on Liver Cirrhosis Determinants project. From 1994 to 1998 all the consecutive cirrhotic inpatients admitted to 19 Italian collaborative hospitals for signs of liver decompensation in whom the diagnosis of liver cirrhosis was made for the first time (259 cases) and one or two gender, age and area of residence matched individuals (416 controls) were recruited. Data on lifetime alcohol intake, usual consumption of 191 food items and on markers of hepatitis B and C viral infection were collected. The analysis of principal components identified a nutritional pattern positively correlated with vegetable and fruit intakes and negatively with animal and no-fruit sugar products. With respect to abstainers, relative risks in consumers of use < or = 25 and > or = 51 g/day of alcohol increased from 0.4 [95% confidence interval 0.0, 5.9] to 9.3 [1.3, 69.0] and from 2.1 [1.1, 4.2] to 18.1 [2.8, 118.3] for the lowest and the highest value of this nutritional pattern, respectively. Diet might therefore modulate the damaging effect of alcohol on the liver.  相似文献   
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Bone sarcomas, such as osteosarcoma (OS) or Ewing sarcoma (ES), frequently arise in the intramedullary region of long bones. Patients affected by bone sarcomas are treated with preoperative aggressive chemotherapy immediately after diagnosis. After chemotherapy, patients undergo surgery that frequently entails the excision of wide bone segments. If a large segment of the bone is lost (defined as a critical defect) the patient undergoes bone reconstruction. Because bone marrow derived stromal stem cells (SSC) offer great promise for cell-based regenerative medicine in bone reconstruction, we investigated whether SSC could be isolated from chemotherapy-treated bone sarcoma patients. We also investigated whether chemotherapy modified SSC differentiation capability. We studied 9 SSC derived from OS and ES patients that had undergone chemotherapy and 5 SSC derived from bone sarcoma patients that had not undergone chemotherapy. SSC could be obtained from all the patients analyzed regardless of whether the patients received chemotherapy or not. Our results also showed that post-chemotherapy SSC can be cultured and expanded ex vivo, these cells retained the ability to differentiate toward the osteogenic lineage in vitro. In conclusion, our results support that SSC cells can be obtained from bone sarcoma patients that undergo chemotherapy and suggest that SSC can be used for cell-based bone reconstruction techniques in bone sarcoma patients treated with preoperative chemotherapy.  相似文献   
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Wood  GS; Garcia  CF; Dorfman  RF; Warnke  RA 《Blood》1985,66(5):1092-1097
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.  相似文献   
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