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11.
Primary angiitis of CNS(PACNS) or granulomatous angiitis of CNS is a rare inflammatory disease of small blood vessels mostly confined to the CNS. The clinical and pathological features of 3 autopsied cases are described. Clinically all the three PACNS patients were young males, age ranging from 19 to 31 years. All presented with varied neurological manifestations. There was no evidence of systemic disease in any of the cases. The ESR was normal and CSF analysis showed chronic meningitic pattern. The cerebral angiogram in one case was normal and the CT scan done in another case showed multiple intracerebral haematoma due to vasculitis. Brain biopsy was not done. Diagnosis was made at post-mortem examination. Histology showed characteristic but variable degree of granulomatous and non-granulomatous angiitis of small vessels. Venulitis with parenchymal haemorrhages was the predominant feature and in one case phlebitis with thrombosis was noted. Since the disease responds to steroids and immunosuppressive therapy, establishing antemortem diagnosis is important. In view of the association of angiitis of CNS with bacteria and viral infections, their role in the evolution of the disease needs to be investigated.  相似文献   
12.
Shankar PP  Wei H  Davee SM  Funk JL 《Brain research》2000,868(2):230-240
Parathyroid hormone-related protein (PTHrP) and the PTH/PTHrP receptor are expressed in most normal tissues, including brain, where PTHrP is though to act locally in an autocrine or paracrine fashion. Previous in situ localization studies in adult rodents have documented CNS PTHrP expression in neurons but not in glial cells. However, a recent report describing immunoreactive PTHrP in human astrocytomas suggests that PTHrP expression may be a marker of dedifferentiation and/or malignant transformation in glial cells. To begin to test this hypothesis, constitutive and regulated PTHrP expression were examined in cultured fetal and transformed (U-373 MG) human astrocytes. PTHrP was expressed in untreated fetal astrocytes and U-373 MG cells, as determined by Northern analysis, immunocytochemical staining, and detection of PTHrP(1-84) protein in conditioned media. Epidermal growth factor and tumor necrosis factor, important growth factors in astrocyte development and malignant transformation, stimulated PTHrP expression in both cell types. Treatment of U-373 MG cells or fetal astrocytes with PTHrP(1-34) consistently inhibited cellular proliferation, as measured by [(3)H]-thymidine incorporation. These findings suggest that PTHrP, a peptide whose expression is induced by mitogens in both immature and transformed human astrocytes, may feedback inhibit cellular proliferation, an effect that may be of importance during malignant transformation as well as CNS development. Furthermore, when combined with previous evidence of PTHrP expression by PTH/PTHrP receptor-positive neurons, our demonstration of regulated PTHrP expression by receptor-positive astrocytes identifies PTHrP as a potential peptide mediator of cross-talk between glial cells and neurons.  相似文献   
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Orally administered banana pulp powder (Musa sapientum var. paradisiaca) was shown to have significant anti-ulcerogenic activity in rats subjected to aspirin, indomethacin, phenylbutazone, prednisolone and cysteamine and in guinea-pigs subjected to histamine. Banana powder not only increased mucosal thickness but also significantly increased [3H]thymidine incorporation into mucosal DNA. Relative to untreated control sections, histological studies showed that banana treatment increased staining by alcian blue in the apical cells with staining noted in the deeper layers of the mucosal glands. Banana-treated and control sections were also stained for DNA by the Feulgen reaction. The banana-treated sections showed a greater aggregation and intensity of pink spots when compared to controls. The present study suggests that banana powder treatment not only strengthens mucosal resistance against ulcerogens but also promotes healing by inducing cellular proliferation.  相似文献   
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BACKGROUND: The use of oral contrast in evaluating children by computed tomography (CT) following blunt trauma is controversial. The aim of this study was to evaluate retrospectively the use of oral contrast with abdominal CT in children with suspected abdominal injury. METHODS: The medical records of 101 children who underwent CT for abdominal trauma between 1993 and 1997 were reviewed for data pertaining to the mechanism of injury, clinical findings and management. Scans were reviewed by a paediatric radiologist and criteria of intestinal injury on CT described by Cox and Kuhn were used: (1) extraluminal air or contrast material, (2) focal area of thickening of bowel wall and mesentery, and (3) free intraperitoneal fluid in the absence of solid organ injury. RESULTS: CT was performed within a median time of 2.4 (range 1-48) h after the injury. On 37 (62 per cent) of 60 scans in children who had oral contrast, the duodenum was not opacified after a mean delay of 30 min. Intestinal injury was suspected on CT in four children. In two children with CT evidence of intestinal injury (with/without oral contrast) rupture of the duodenojejunal flexure (n = 1) or ileal perforation (n = 1) was found at laparotomy. Two children had a false-positive scan, leading to negative laparotomy; one scan with oral contrast incorrectly suggested a duodenal leak and in another child CT without oral contrast showed thickening of bowel wall with free intraperitoneal fluid but no specific intestinal injury was identified at laparotomy. One patient had two negative CT scans (with and without oral contrast) and underwent laparotomy for clinical suspicion of bowel injury; rupture of the splenic flexure of the colon was found at laparotomy. CONCLUSION: CT is not reliable for diagnosing intestinal injuries and this is not improved by use of oral contrast. Omission of oral contrast was not associated with delay in the diagnosis of intestinal injury. Since intestinal injuries are uncommon in children, a prospective multicentre study would determine more precisely the role of the routine use of oral contrast.  相似文献   
17.

Background

Constipation is a common problem in childhood, and various radiologic methods have been advocated for investigation. Colonic transit time (CTT) has been used in adults to investigate colonic motility, but few studies evaluate this method in children. Data on CTT in the normal paediatric population are scarce.

Methods

The colonic transit time was measured in 22 healthy children (median age, 10 years; range, 4 to 15 years) by Abrahamsson’s method. Children took bolus ingestions of radiopaque markers on 6 consecutive days, and on day 7 a single abdominal x-ray was performed. This was evaluated for total and segmental colonic transit time.

Results

The mean total CTT was 40 hours, and the upper limit of normal (95th percentile) was 84 hours. The upper limit of normal for segmental transit time was as follows: 14 hours for the ascending, 33 hours for the transverse, 21 hours for the descending, and 41 hours for the rectosigmoid colon.

Conclusions

CTT provides an objective measure to assess childhood constipation. To date, 6 studies using 5 different methods have been published reporting values for healthy children. Comparing these, Abrahamson’s method has low radiation exposure and is well tolerated. This study contributes additional normal values in children.  相似文献   
18.
BACKGROUND: Tumor necrosis factor related apoptosis-inducing ligand/Apo2 ligand (TRAIL/Apo-2L) is a novel anticancer agent, capable of inducing apoptosis preferentially in tumor and transformed cells. TRAIL-R1/death receptor (DR)4 and TRAIL-R2/DR5 are members of the tumor necrosis factor (TNF) receptor family, and can be activated by the TRAIL. We examined the clinical potential of chemotherapeutic drugs and TRAIL for the treatment of prostate cancer. METHODS: Prostate and bladder cancer cells were exposed to chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) and TRAIL. Cell viability was measured by sodium 3'[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) assay; expressions of death receptors and Bcl-2 family members were measured by Western blotting, ELISA and ribonuclease protection assay. PC-3 tumor cells xenografted athymic nude mice were exposed to chemotherapeutic drugs and TRAIL, either alone or in combination, to measure tumor growth and survival of mice. Apoptosis was measured by annexin V-FITC/propidium iodide staining, and terminal deoxynucleotidyltransferase-mediated nick end labeling assay. Caspase-3 activity was measured by the Western blotting and immunohistochemistry. RESULTS: TRAIL induced apoptosis with varying sensitivity. Chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) significantly augmented TRAIL-induced apoptosis in cancer cells through up-regulation of DR4, DR5, Bax, and Bak, and induction of caspase activation. Mitochondrial pathway enhanced the synergistic interactions between drugs and TRAIL. The sequential treatment of mice with chemotherapeutic drugs followed by TRAIL induced caspase-3 activity, and apoptosis, inhibited angiogenesis, completely eradicated the established tumors, and enhanced survival of mice. CONCLUSIONS: Chemotherapeutic drugs can be used to enhance the therapeutic potential of TRAIL in prostate cancer.  相似文献   
19.
Introduction

Surgical decompression is standard care in the treatment of degenerative spondylolisthesis in patients with symptomatic lumbar spinal stenosis, but there remains controversy over the benefits of adding fusion. The persistent lack of consensus on this matter and the availability of new data warrants a contemporary systematic review and meta-analysis of the literature.

Methods

Multiple online databases were systematically searched up to October 2022 for randomized controlled trials (RCTs) and prospective studies comparing outcomes of decompression alone versus decompression with fusion for lumbar spinal stenosis in patients with degenerative spondylolisthesis. Primary outcome was the Oswestry Disability Index. Secondary outcomes included leg and back pain, surgical outcomes, and radiological outcomes. Pooled effect estimates were calculated and presented as mean differences (MD) with their 95% confidence intervals (CI) at two-year follow-up.

Results

Of the identified 2403 studies, eventually five RCTs and two prospective studies were included. Overall, most studies had a low or unclear risk of selection bias and most studies were focused on low grade degenerative spondylolisthesis. All patient-reported outcomes showed low statistical heterogeneity. Overall, there was high-quality evidence suggesting no difference in functionality at two years of follow-up (MD − 0.31, 95% CI − 3.81 to 3.19). Furthermore, there was high-quality evidence of no difference in leg pain (MD − 1.79, 95% CI − 5.08 to 1.50) or back pain (MD − 2.54, 95% CI − 6.76 to 1.67) between patients undergoing decompression vs. decompression with fusion. Pooled surgical outcomes showed less blood loss after decompression only, shorter length of hospital stay, and a similar reoperation rate compared to decompression with fusion.

Conclusion

Based on the current literature, there is high-quality evidence of no difference in functionality after decompression alone compared to decompression with fusion in patients with degenerative lumbar spondylolisthesis at 2 years of follow-up. Further studies should focus on long-term comparative outcomes, health economic evaluations, and identifying those patients that may benefit more from decompression with fusion instead of decompression alone. This review was registered at Prospero (CRD42021291603).

  相似文献   
20.
M.G Prasad  N.S Shankar 《The Foot》1998,8(4):223-225
Fifty cases of hallux valgus treated by Keller's arthroplasty were reviewed over an average period of 91 months. This revealed radiographic changes in the first metatarsal head suggestive of avascular necrosis (AVN) in as many as eight feet. The blood supply to the first metatarsal head and probable cause of these AVN changes are discussed.  相似文献   
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