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22.
Keratomalacia in a neonate secondary to maternal vitamin A deficiency   总被引:1,自引:0,他引:1  
A 40-day-old male child was admitted with complaints of not opening eyes from 2–3 days after birth. A diagnosis of X3-B keratomalacia was made. The treatment was done with vitamin-A to which the patient had responded. The mother of the baby had a history of night blindness throughout the pregnancy for which she was also treated. Keratomalacia secondary to vitamin-A deficiency is rare in neontes, although in children it is reported form developing countries.  相似文献   
23.
Leishmaniasis, a zoonotic protozoan disease, starts with the inoculation of the Leishmania promastigotes into the skin at the time of blood ingestion by a female sandfly. The infection of leishmaniasis is established when the Leishmania organisms start their own intracellular multiplication after having been phagocytized by the host's macrophages. In the earliest stage of the infection, therefore, the attachment of the promastigates to the macrophages is essential. We incubated a mixed culture of macrophages (JM774-1A) and Leishmania (Leishmania) major for 6 hours in vitro and observed the process of the attachment between the parasite and host cell by scanning electron microscope. We found for the first time that the attachment between the two occurred at the site of the parasite body, in addition to the previously reported sites of the flagellar tip, flagellar base, and aflagellar tip (posterior pole).  相似文献   
24.
Primary adenocarcinoma of the appendix is rare, and since Berger first recognised the neoplasm in 1882, fewer than 250 cases have been recorded. Adenocarcinoma of the appendix is never suspected pre-operatively, being usually first discovered by histological examination. Ileocaecal resection during the first operation and right hemicolectomy for a carcinoma diagnosed after appendicectomy remain the main stay of treatment.  相似文献   
25.
The strength of intravascular 192Ir sources is typically measured by the manufacturer before shipment, and treatment planning is based on that assay. However, in-house verification of source strength is required at some institutions by state law or internal policy, is recommended by the AAPM TG 60 report on intravascular brachytherapy, and is considered a necessity by many medical physicists. To accommodate the long sources used in intravascular therapy, special well chambers with extended regions of constant response have been designed. To allow assays using a widely available standard well chamber, we have measured its position dependent sensitivity and derived from it a table of correction factors that account for the extended length of intravascular sources. An experimental verification shows that application of these correction factors yields assays with sufficient accuracy for routine quality assurance tests.  相似文献   
26.
PURPOSE: Studies suggest that HU values on non-contrast computerized tomography may predict the ability to fragment urinary calculi. We determined whether the HUs of in vivo urinary stones could be used to predict the stone-free rates after extracorporeal shock wave lithotripsy. MATERIALS AND METHODS: We evaluated 50 patients who underwent extracorporeal shock wave lithotripsy for 5 to 10 mm. upper urinary tract stones. Chemical analyses and HU calculations were performed for each stone and posttreatment radiographic assessment categorized patients into a stone-free or a residual stone group. Statistical analysis was performed using the Student t test to compare mean HU values in the 2 groups. RESULTS: Of the patients 32 (64%) were stone-free and 18 (36%) had residual stones. Mean values +/- SEM for the stone-free and residual stone groups were significantly different (551.20 +/- 46.66 versus 926.20 +/- 51.42 HU, p <0.0001). A total of 30 calculi (60%) were located in the ureter, including 21 in the stone-free group and 9 in the residual stone group with a mean value of 505.10 +/- 46.66 and 888.70 +/- 102.00 HU, respectively, which was significantly different (p = 0.0005). A total of 20 calculi (40%) were located in the kidney, including 11 in the stone-free group and 9 in the residual stone group with a mean value of 558.40 +/- 62.38 and 905.10 +/- 61.49 HU, respectively, which was significantly different (p = 0.001). CONCLUSIONS: These findings suggest that HU measurement of urinary calculi on pretreatment non-contrast computerized tomography may predict the stone-free rate. This information may be beneficial for selecting the preferred treatment option for patients with urinary calculi.  相似文献   
27.
Kim RY  Pareek P 《Brachytherapy》2003,2(4):166-206
PURPOSE: To analyze the dose-volume histograms (DVHs) of the tumor volume and organs at risk by CT-based treatment planning compared with conventional radiography-based treatment planning for intracavitary brachytherapy in cancer of the cervix. METHODS AND MATERIALS: Fifteen consecutive patients with cancer of the cervix (1 IB1, 3 IB2, 7 IIB, 4 IIIB) were treated with plastic CT-compatible HDR intracavitary applicators and underwent postimplant pelvic CT scans with applicators in place. CT-images were transferred to the PLATO treatment planning system. The gross tumor volume (GTV) and organs at risk were digitized. Dwell positions in the uterine tandem and colpostats were identified and registered for each patient. All patients were treated with 6 Gy per fraction to Point A using radiography-based planning. For the CT-based planning, DVHs were performed for the GTV, bladder, rectum, sigmoid colon, and small bowel in the pelvis. The dose delivered to 3% volume of the organs at risk (D3%) was compared with the respective ICRU reference doses. RESULTS: For stage IB(I), IB2, IIB, and IIIB disease the mean GTV was 20.5 cc, 56.6 cc (54.2-57.2), 63.7 cc (55.4-118.9), and 77.6 cc (49.4-102.9), respectively. The 6 Gy pear-shaped volume (PSV) encompassed an average GTV of 98.5%, 89.5%, 79.5%, and 59.5% for stages IBI, IB2, IIB, and IIIB, respectively. The mean dose for the ICRU bladder point and D3% was 3.72 Gy (1.51-5.53) and 4.74 Gy (1.70-10.10), respectively. The mean dose for the ICRU rectal point and D3% was 3.97 Gy (2.09-5.37) and 3.52 Gy (2.05-4.08), respectively. The D3% for the sigmoid colon was highest (3.88 Gy), followed by the rectum (3.52 Gy), and the small bowel (3.36 Gy). CONCLUSION: Radiography-based conventional treatment planning overestimates tumor dose, especially those with more advanced tumors. To correlate DVHs for tumor control, improved tumor imaging is necessary.  相似文献   
28.
Bone and joint complications related to Gaucher disease   总被引:3,自引:0,他引:3  
There is a broad spectrum of Gaucher disease-related skeletal complications, ranging from asymptomatic osteopenia to osteonecrosis (of the shoulders and hips) with secondary degenerative joint disease. Characterization of the pattern and severity of bone involvement in the individual patient requires the application of conventional and advanced radiographic techniques. The introduction of enzyme replacement therapy (ERT) for this inborn error of glycosphingolipid metabolism has focused great interest in determining the nature and extent of the bone responses with this mode of treatment. The multifactorial etiology of the bone complications necessitates a multifaceted approach, combining pharmacologic strategies with physical therapy and orthopedic intervention. As bone disease can lead to chronic pain and debility with a resultant adverse impact on quality of life, it is important that patients be monitored closely and that early intervention with ERT prior to established bone disease (infarction and fibrosis) be considered.  相似文献   
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30.
Papillon-Lefevre Syndrome   总被引:1,自引:0,他引:1  
Papillon-Lefevre syndrome in six Saudi children in the same family is described. The parents were unaffected, and parental consanguinity was present. Palmoplantar keratosis started at the age of 1 1/2 years. The loss of deciduous teeth was a consequence of juvenile periodontitis. All essential features of the syndrome were present in this series.  相似文献   
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