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51.
Primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma is an extremely rare disease. A 65-year-old female patient with chronic hepatitis B presented with multiple solid masses in segment (S) 4, S5, and S6 of the liver. The nodule in S5 was diagnosed preoperatively as hepatocellular carcinoma by computed tomography, magnetic resonance imaging, and angiography. The nodule in S4 was initially interpreted as lymphoid follicles by needle biopsy. Segmentectomy of S5 and partial resection of S6 were performed. Microscopic examination of the S5 nodule revealed moderately differentiated hepatocellular carcinoma. The nodule from S6 showed nodular proliferation of atypical intermediate to medium-sized lymphoid cells in the portal area and lymph epithelial lesions of bile ducts. The atypical lymphoid cells were positive for LCA, L-26 and bcl-2 and negative for UCHL-1. These features were consistent with the diagnosis of MALT lymphoma. This is the first case report of synchronous hepatic MALT lymphoma and hepatocellular carcinoma associated with chronic hepatitis B.  相似文献   
52.
OBJECTIVE: Since the primary hematological complication in both pediatric HIV-1 and malaria is anemia, co-infection with these pathogens may promote life-threatening severe malarial anemia (SMA). The primary objective of the study was to determine if HIV-1 exposure [HIV-1(exp)] and/or HIV-1 infection [HIV-1(+)] increased the prevalence of SMA in children with acute malaria. DESIGN: The effect of HIV-1 exposure and HIV-1 infection on the prevalence of SMA (hemoglobin < 6.0 g/dl), parasitemia (parasites/microl), and high-density parasitemia (HDP, >or= 10 000 parasites/mul) was investigated in children 相似文献   
53.
Research in malaria-endemic areas is usually focused on malaria during early childhood. Less is known about malaria among older school age children. The incidence of clinical attacks of malaria was monitored, using active case detection in primary schools, in two areas of western Kenya that differ in the intensity of transmission. Clinical malaria was more common in schools in the Nandi highlands, with a six-fold higher incidence of malaria attacks during the malaria epidemic in 2002, compared with school children living in a holoendemic area with intense perennial transmission during the same period. The high incidence coupled with the high parasite densities among cases is compatible with a low level of protective immunity in the highlands. The malaria incidence among school children exposed to intense year-round transmission (26 per 100 school children per year) was consistent with reports from other holoendemic areas. Taken together with other published studies, the data suggest that malaria morbidity among school age children increases as transmission intensity decreases. The implications for malaria control are discussed.  相似文献   
54.
We have shown previously that various human cancer cell lines undergo morphological changes and internucleosomal DNA fragmentation characteristic of apoptosis after exposure to ionizing radiation or isoflavones. Here, we assessed the role of p53 gene in cell cycle and apoptosis following treatment of 11 gastric carcinoma cell lines with gamma-rays, genistein, biochanin A, or daidzein. Cell survival was measured by trypan blue staining, and apoptosis was assessed by fluorochrome staining. The rate of cell survival and apoptosis of the cells by gamma-irradiation or isoflavones did not correlate with p53 gene abnormalities. Flow cytometric measurement of DNA content demonstrated that while gamma-irradiation and genistein induced G(2) arrest, biochanin A and daidzein blocked the cell cycle of all carcinoma cells at G(1) phase. At multiple time points following irradiation, G(2) arrest was observed at 12-16 h in the wild-type and mutant p53 cell lines. Induction of p53 and p21 proteins was not observed in wild-type p53 lines after exposure to gamma-irradiation or isoflavones by Western blotting. Moreover, transfection of the wild-type p53 gene into MKN-1 cells failed to induce G(1) arrest by gamma-irradiation and genistein. Based on these results, we hypothesize that gastric cancer cells may possess a signal pathway which is different from the usual mechanisms of the p53-mediated DNA damage response in normal or hematopoietic tumor cells.  相似文献   
55.
    
Closed reduction (CR) as an initial treatment for developmental hip dysplasia of the hip (DDH) in children aged 24 to 36 months is debatable; however, it could have better results than open reduction (OR) or osteotomies, because it is minimally invasive. The purpose of this study was to evaluate the radiological results in children (24–36 months) with DDH initially treated with CR. Initial, subsequent, final anteroposterior pelvic radiological records were retrospectively analyzed. The International Hip Dysplasia Institute was used to classify the initial dislocations. To evaluate the final radiological results after CR (initial treatment) or additional treatment (CR failed), the Ömeroğlu system was used (6 points excellent, 5 good, 4 fair-plus, 3 fair-minus, and ≤2 poor). The degree of acetabular dysplasia was estimated using the initial acetabular index and the final acetabular index, Buchholz–Ogden classification was used to measure avascular necrosis (AVN). A total of 98 radiological records were eligible, including 53 patients (65 hips). Fifteen hips (23.1%) were redislocated, OR with femoral osteotomy and pelvic osteotomy was the preferred surgical treatment 9 (13.8%). The initial acetabular index versus final acetabular index in total population was (38.9º ± 6.8º) and (31.9º ± 6.8º), respectively (t = 6.5, P < .001). The prevalence of AVN was 40%. Overall AVN in OR, femoral osteotomy and pelvic osteotomy were 73.3% versus CR 30%, P = .003. Unsatisfactory results ≤ 4 points on the Ömeroğlu system were observed in hips that required OR with femoral and pelvic osteotomy. Hips with DDH treated with CR initially might had better radiological results than those treated with OR and femoral and pelvic osteotomies. Regular, good, and excellent results, ≥4 points on the Ömeroğlu system, could be estimated in 57% of the cases, in whom CR was successful. AVN is frequently observed in hips with failed CR.  相似文献   
56.
In sub-Saharan Africa, self-disclosure of HIV-positive status may be a pivotal action for improving access to prevention of mother-to-child transmission services. However, understanding of HIV stigma and disclosure, and their effects on demand for care remains incomplete – particularly in the current context of new antiretroviral therapy guidelines. The purpose of this study was to explore these issues among self-disclosed couples living in southwest Kenya. We conducted 38 in-depth interviews with HIV-positive pregnant or postpartum women and their male partners. Of the 19 couples, 10 were HIV seroconcordant and 9 were serodiscordant. The textual analysis showed that HIV stigma continues to restrict full participation in community life and limit access to care by promoting fear, isolation and self-censorship. Against this backdrop, however, participants’ narratives revealed varying forms and degrees of resistance to HIV stigma, which appeared to both produce and emerge from acts of self-disclosure. Such disclosure enabled participants to overcome fears and gain critical support for engaging in HIV care while further resisting HIV stigma. These findings suggest that programme interventions designed explicitly to stimulate and support processes of HIV stigma resistance and safe self-disclosure may be key to improving demand for and retention in HIV services.  相似文献   
57.
A rapid results initiative (RRI) aimed at increasing male involvement in prevention of mother-to-child transmission (PMTCT) and service uptake among pregnant women at 116 antenatal clinics in Western Kenya was compared at baseline, during the RRI, and 3-months post-RRI. Male involvement increased from 7.4 to 54.2% during RRI (risk difference [RD] 0.47, CI 0.45–0.48) then 43.4% post-RRI (RD 0.36, CI 0.35–0.37). Among HIV-infected women, facility delivery increased from 40.0 to 49.9% (RD 0.10, 95% CI 0.06–0.13) and 65.0% post-RRI (RD 0.25, 95% CI 0.22–0.28). HIV-infected pregnant women linkage to HIV care increased from 58.6 to 85.9% (RD 0.27, CI 0.24–0.30) and 97.3% post-RRI (RD 0.39, CI 0.36–0.41). Time to ART initiation reduced from 29 days (interquartile range [IQR] 6–56) to 14 days (IQR 0–28) to 7 days (IQR 0–20). A male-centered RRI can significantly increase men’s engagement in antenatal care leading to improved partner utilization of PMTCT and antenatal services.  相似文献   
58.
59.
BACKGROUND: Road Traffic Accidents (RTAs) are a major cause of morbidity and mortality in Kenya. Victims may suffer multiple injuries including maxillofacial injuries. In most developing countries RTAs are the leading cause of maxillofacial injuries. In an attempt to reduce RTAs, the government of Kenya has enacted a legislation requiring mandatory fitting of speed governors and safety belts by passenger service vehicles. OBJECTIVE: To describe the characteristics and pattern of maxillofacial and associated injuries sustained in road traffic accidents. DESIGN: A cross-sectional study. SETTING: Kenyatta National Hospital (KNH). SUBJECTS: All patients involved in RTAs brought to casualty and the dental department of KNH as well as accident victims admitted to the KNH mortuary over a four- month period from September 2004 to December 2004. RESULTS: Four hundred and thirteen (85.7%) had non-fatal injuries whereas 69 (14.3%) had sustained fatal injuries. Males in the 21-30-year age group were the most affected. Most accidents occurred during weekends with pedestrians being the leading casualties in 59.5% and 71.4% of non-fatal and fatal cases respectively. Most accidents were caused by passenger service vehicles (matatus) which were responsible for 62% and 40.6% of non-fatal and fatal injuries respectively. Non-use of safety belts was reported in 56.6% of the cases who suffered non-fatal injuries. In the non-fatal category 89.6% of the casualties had soft tissue injuries (STIs) involving the craniofacial region with facial cuts being the majority (69.2%). Two hundred and seventy three (66.1%) incidents of other STIs than those of the head region were noted, the lower limbs accounting for 45.4% of these. Only 5.1% of the casualties with non-fatal injuries had fractures involving the maxillofacial skeleton. Skeletal injuries other than those involving the maxillofacial region were found in 142 (34.1%) incidents. In the fatal category head injury alone was the leading cause of death accounting for 37.7% of the cases followed by head and chest injuries combined which were responsible for 13% of the cases. CONCLUSION: Injuries to the maxillofacial skeleton appear to be uncommon in this series. Pedestrians in their third decade of life are most affected with passenger service vehicles being responsible in the majority of the cases. RECOMMENDATIONS: Interventional programmes targeting pedestrians and those in the third and fourth decades of life should be enacted.  相似文献   
60.
The expression of p53-Inducible cylln-dependent kinase Inhibitor, p21WAF1/CIP1 in non-neopiastic mucosa, adenoma and adenocarclnoma of the colorectum was examined by immunohistochemistry and western bootting and Its relation with the expression of p53 protein was analyzed. Non-neoplastic epithelial cells at the surface area showing no proitferative activity expressed p21WAF1/CIP1.The expression of p21WAF1/CIP1 was lmmunohistochemlcally detected in 55% (206/377 of the adenomas and 66% (190/289) of the adenocarcinomas, respectively. The lncldence of strongly positive cases was significantly higher In the adenocarcinomas (27%) than In the adenomas (18%) ( P< .05). The incidence of cases wtth strong p21WAF1/CIP1 expression was higher In stages 0,1 and 2 carcinomas than in stages 3 and 4 carcinomas ( P <0.05). A decrease in the incidence of cases with strong expression was detected in carclnomas Invading deeper than muscularis propria. The influence of strongly positive cases was signiflcantly lower in carcinomas with lymph node metastasis than those without metastasls ( P <0.05). The expression of p21 as well as p53 detected by western blotting was compatlble with the results of lmmunohistochemlstry in most cases examined. However, there was no significant correlatlon between the expression of p21WAF1/CIP1 and the abnormal accumulation of p53. These findlngs overall suggest that: (i) the physiological expression of p21WAF1/CIP1 may be associated with cellular senescence of colorectal mucosa; (ii) reduced expression of p21WAF1/CIP1 participate in the progression of colorectal carcinoma; and (iii) p53-Independent paulway may be considerably Involved In the inductions of p21WAF1/CIP1.  相似文献   
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