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771.
BACKGROUND/AIMS: Spontaneous gastroduodenal perforation is a rare and lethal complication in cancer patients receiving chemotherapy. METHODOLOGY: Data of 9 patients with spontaneous gastroduodenal perforation occurring during chemotherapy were reviewed. RESULTS: All 9 patients were male with an average age of 54.4+/-2.5 years. The primary malignancies included 5 head and neck cancers, 2 esophageal cancers, 1 malignant lymphoma, and 1 hepatocellular carcinoma. Abdominal pain was the most common symptom. The average interval between the onset of symptoms and surgery was 2.9+/-0.7 days (range: 16 hours to 7 days). Perforation was located on the duodenum (6 patients) and on the lower part of the body of the stomach (3 patients). Simple closure of the perforation was performed on 8 patients, and subtotal gastrectomy on 1 patient. Culture of the ascitic fluid of 8 patients revealed E. coli, Klebsiella pneumoniae, streptococcus viridans, and enterococcus. Four patients (44.4%) had post-operative complications. The 30-day post-operative mortality was 44.4% (4/9). Three patients died of sepsis with multiple organ failure, and 1 died of hepatic failure. Age, anaemia, leukopenia, serum albumin levels, impaired renal or liver functions are not significant operative risk factors. Pre-operative shock is a significant factor in predicting operative mortality and complications. CONCLUSIONS: High index with suspicion of the disease with early treatment may improve survival of cancer patients with spontaneous gastroduodenal perforation.  相似文献   
772.
773.
A simple and fast method for diffusion blotting of proteins from precast SDS-PAGE gels (0.5 mm) was developed. The efficiency of protein transfer was evaluated using 14C labelled proteins. Diffusion blotting for three minutes, gave a transfer of 10% compared to electroblotting. By doubling the transfer time for each subsequent imprint, four imprints were made from the same lane with similar amounts of protein transferred onto each imprint. With a transfer time of three minutes each, it was possible to obtain at least ten imprints with all the proteins visible in all the imprints. There was no detectable loss in resolution as compared to electroblotting. The method also works well with an immuno-detecting system. The number of imprints which can be obtained, is dependent on the sensitivity of the detection system and the amount of protein applied. The greatest advantage of diffusion blotting compared to electroblotting is that several imprints can be made from each lane, and different antisera can be tested on identical imprints. The gel remains on its plastic support which prevents it from stretching and compression; this ensures identical imprints and facilitates more reliable molecular mass determination. If only a few imprints are made, sufficient protein remains within the gel for general protein staining. These advantages make diffusion blotting the method of choice when quantitative protein transfer is not required.  相似文献   
774.
PURPOSE: The objective of this study was to assess the complications and efficacy of gastrostomy (GT) feedings in pediatric cancer patients. PATIENTS AND METHODS: We reviewed the medical records of 33 pediatric cancer patients who received enteral nutrition via a GT. RESULTS: Median age was 9.4 years (range, 1-19.8 years), and 28 of the 33 patients had solid tumors. Seventeen patients had a significant weight loss (median, 8.5%) and therapy-related weight loss was anticipated in 16 patients. The GT device was placed an average of 5.5 months after diagnosis. Twenty-five patients were fed via a tube and eight via a button device. The tube was placed surgically in 21 cases (including all eight button types) and endoscopically in 12. Nutritional support lasted a median of 9.5 months. One or more complications occurred in 30 patients and were categorized as (a) insertion site reactions (inflammation, 23; infection/colonization, 14; exuberant granulation tissue, 6); (b) mechanical problems (leaking, 3; obstruction, 2; breakage, 1; accidental dislodgement, 2); (c) insertion site bleeding, 8; and (d) feeding intolerance, 12. Only one insertion site cellulitis progressed to a systemic infection. All eight patients with a button GT experienced insertion site complications, with local infection occurring significantly more often in patients with the button than in those with the tube GT. There were no significant associations between insertion technique and type of complication. Twenty-seven patients (82%) achieved or maintained ideal body weight with this intervention. CONCLUSIONS: GT feeding was associated with minor complications, but permitted effective nutritional support for pediatric cancer patients.  相似文献   
775.
It has been proposed that extremely low frequency (ELF) magnetic fields may enhance tumorigenesis through a co-promotional mechanism. This hypothesis has been further tested using the two-stage model of mouse skin carcinogenesis, i.e. 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced promotion of skin tumors in mice initiated by a single subcarcinogenic dose of 7,12-dimethylbenz[a]anthracene. Experimentation described herein utilized the SENCAR mouse and examined the effect of a magnetic field on skin tumor promotion induced by three different doses of TPA within its dose-response range, i.e. 0.85, 1.70 or 3.40 nmol, administered twice per week. SENCAR mice (56/treatment group) were exposed to a 60 Hz magnetic field having a flux density of 2 mT for 6 h/day for 5 days/week and compared with mice exposed to the ambient magnetic field. Tumor incidence and multiplicity were monitored weekly for 23 weeks of TPA promotion. Statistical evaluation of the effects of the magnetic field on tumor incidence and multiplicity did not reveal any statistically significant effects; thus, within the sensitivity limits imposed by the animal model and the exposure parameters employed, no promotional or co-promotional effect of a 2 mT magnetic field on skin tumor development in SENCAR mice could be demonstrated.  相似文献   
776.
Platelets are small, disc-shaped, anucleated cells formed by fragmentation of megakaryocytes in the bone marrow. They circulate in blood with a lifespan of 7 to 10 days and, together with fibrin, form hemostatic plugs at sites of vessel injury. Abnormalities of platelets, either quantitative or qualitative, may cause clinically significant bleeding with resultant morbidity and, on occasion, mortality. This review will focus on platelet disorders in neonates, defined as infants of up to 4 months of age. Special emphasis will be given to the physiology of platelet function in healthy and sick newborn infants. The review will be divided into sections as follows: role of platelets in hemostasis, platelet function in newborn infants, quantitative platelet disorders, qualitative platelet disorders, and platelet transfusion therapy.  相似文献   
777.
Three cases with characteristic features of nodular (pseudosarcomatous) fasciitis arising in the dermis are described. This is only the second report documenting a dermal location for this condition. One of the three cases also showed features of intravascular fasciitis. A fourth case of intravascular fasciitis arising in periocular tissue is included. The differential diagnosis of dermal fasciitis includes benign fibrous histiocytoma, pyogenic granuloma, peripheral nerve tumors, cutaneous smooth muscle tumours, spindle cell carcinoma, spindle cell melanoma, dermatofibrosarcoma protuberans and atypical fibroxanthoma.  相似文献   
778.
OBJECTIVE: To evaluate the presence of tyrosine-rich crystalloids (TRC) in fine needle aspiration (FNA) specimens of pleomorphic adenomas of salivary gland. STUDY DESIGN: FNA specimens from 12 patients were reviewed, and the percentage of cases showing TRC was established. The staining properties of the TRC were evaluated as well as spontaneous fluorescence under ultraviolet (UV) light. RESULTS: Of the 12 pleomorphic adenomas, 4 showed TRC (30%) in the smears. Among the eight cytologically negative cases there were two that showed a few TRCs on histology. All positive cases were from African American patients. TRC stained weakly with Papanicolaou stain. TRC were deep blue with Diff-Quik. They fluoresced under UV light. CONCLUSION: TRC could be detected in FNA specimens. They were best seen under UV light. The Papanicolaou technique stained TRC very pale, making them difficult to see. Diff-Quik stained TRC dark blue, mimicking deposits of dye. The amount of TRC in histology paralleled the detection rate in cytology.  相似文献   
779.
Murine models such as NZB/W F1, NZB.H-2bm12 and MRL.lpr/lpr mice have provided greater insight into the pathogenic mechanisms of lupus. To understand further the roles of T cells and cytokines in the pathogenesis of murine lupus, 11 cloned anti-DNA antibodies augmenting autoreactive T cell lines were derived from NZB/W F1 mice. All these autoreactive cells responded to syngeneic splenic cells and helped syngeneic B cells to produce anti-DNA antibodies, especially the IgG antibody. Ten out of 11 autoreactive T cell lines expressed neither CD4 nor CD8 cell surface markers on their surface. In addition, the cytokine production pattern of these autoreactive T cell lines was predominantly of type 0 (Th0) or type 2 T helper cells (Th2). To further investigate the role of accessory molecules in the activation of these autoreactive T cell lines, expression of IL-2R and heat-stable antigen (HSA) on these autoreactive T cells was analysed. Results suggest that the HSA played a critical role in the activation and function of these double-negative cloned autoreactive T cells.  相似文献   
780.
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