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71.
BACKGROUND: Camel collision accidents are a common occurrence in Saudi Arabia, with a high rate of mortality and morbidity. Isolated injuries are rare because of the nature of impact sustained by the person. CASE DESCRIPTION: A 4-year-old child with an isolated depressed skull fracture resulting from a camel collision is described. The other occupants of the car were crushed to death. The child sustained only an impact to his head, causing a compound depressed skull fracture with localized cortical damage. CONCLUSIONS: Camel collision accidents are a common cause of mortality and morbidity in Saudi Arabia. Isolated skull injuries are rare and result from a localized impact. This is the first report of a compound depressed skull fracture from such an incident. The extent of the problem and efforts toward prevention are described.  相似文献   
72.
E C Schlorff  K Husain  S M Somani 《Alcohol》1999,18(2-3):203-214
This study was designed to investigate the dose as well as time dependent effects of ethanol on testicular antioxidant defense system in rats. Male Fischer 344 rats were administered ethanol at a dose of 2, 4, and 6 gm/kg orally and control received equal volume of saline and sacrificed 1 h after ethanol ingestion. For time course study, animals were administered ethanol 4 g/kg orally and sacrificed at 1.5, 2, 4, and 6 h after ethanol ingestion. Testicular ethanol concentration increased with increasing doses of ethanol. Copper zinc-superoxide dismutase (CuZn-SOD) activity significantly decreased in the testes of rats treated with increasing doses of ethanol whereas manganese-superoxide dismutase (Mn-SOD) activity significantly increased in a dose dependent manner (181, 186, and 195% of control, respectively). Testicular glutathione (GSH) and malondialdehyde (MDA) levels did not significantly alter with increasing doses of ethanol one hour after ethanol ingestion. Ethanol concentration decreased in the testes with an increase in time after ethanol ingestion. Testicular CuZn-SOD activity significantly decreased whereas Mn-SOD activity increased with an increase in time after ethanol ingestion. Testicular catalase (CAT) activity significantly decreased at 2 h postethanol ingestion. Testicular MDA levels significantly increased at 4 and 6 h after ethanol ingestion indicating that end product of lipid peroxidation. MDA, takes considerable time to form in the testes. A significant decrease in the ratios of CAT/Mn-SOD and glutathione peroxidase (GSH-Px)/Mn-SOD in the testes of rat suggests the ability of mitochondria to scavenge reactive oxygen species (ROS). It is suggested that antioxidant enzyme ratios may be used as an important parameter to determine ethanol induced oxidative stress in the tissues.  相似文献   
73.
PURPOSE: To study the long-term effects of photodynamic therapy (PDT), using liposomal benzoporphyrin derivative (BPD) or Verteporfin, on experimental choroidal neovascularization (CNV) and on normal retina and choroid (with no CNV) in the cynomolgus monkey eye. METHODS: Photodynamic therapy was performed in 8 cynomolgus monkey eyes with experimental CNV induced by laser injury. The effect of PDT on normal retina and choroid (with no CNV) was studied in 9 monkey eyes. Liposomal BPD was administered intravenously (0.375 mg/kg) either as a bolus, as a slow infusion over 32 minutes, or as a fast infusion over 10 minutes. Photodynamic therapy was performed using light at a wavelength of 689 or 692 nm, with an irradiance of 600 mW/cm2 and fluence of 150 J/cm2. Follow-up studies, including fundus photography and FA, were performed at 24 hours after PDT and then weekly. Indocyanine green and BPD angiography were performed in selected cases. Tissues were examined with light and electron microscopy at the end of follow-up. RESULTS: Twenty-three of the 32 areas of CNV treated with PDT showed absence of angiographic leakage at 24 hours. Twenty-eight areas of CNV were followed for 4 weeks; 22 of 28 showed absence of angiographic leakage at 2 weeks; and 20 of 28 at 4 weeks of follow-up. Forty spots on the normal retina and choroid were treated with PDT and were followed for 4 to 7 weeks. These spots showed pigment-laden cells in the outer retina, variably pigmented retinal pigment epithelium (RPE) in the treated area, intact neurosensory retina, and reperfusion of the choriocapillaris. CONCLUSIONS: Photodynamic therapy leads to absence of angiographic leakage for at least 4 weeks in experimental CNV in the monkey model. In the normal monkey eye the RPE and choriocapillaris show generalized recovery with preservation of the neurosensory retina 7 weeks after PDT.  相似文献   
74.
Synthesis of fatty acid ethyl esters (FAEEs), fatty acid methyl esters (FAMEs), and fatty acid anilides (FAAs) in humans and/or experimental animals and in vitro have been reported by us and other investigators. In previous studies, we have demonstrated that fatty acid ethyl ester synthase (FAEES), purified from rat liver microsomes, is structurally and functionally identical to the rat liver microsomal carboxylesterase (pI 6.1) and suggested a role in the conjugation of a variety of xenobiotic alcohols with endogenous fatty acids (B. S. Kaphalia, R. R. Fritz, and G. A. S. Ansari, Chem. Res. Toxicol. 11, 211-218, 1997). However, hepatic FAEES was found to be structurally and functionally different from that of pancreas. Therefore, the present study was undertaken to determine structural and functional interrelationships among the enzyme(s) involved in the synthesis of FAEEs, FAMEs, and FAAs, in HepG2 and AR42J cells using tri-o-tolyl phosphate (TOTP), a specific inhibitor for beta-esterases. Synthesis of FAEEs, FAMEs, and FAAs, studied in the HepG2 cells, was found to be dose- and time-dependent following incubation with methanol, ethanol, or aniline, respectively. Approximately 86-90% inhibition of FAEE, FAME, and FAA synthesizing activities was found in HepG2 cells following exposure to 2.5 microM TOTP. Identical profiles of dose- and time-dependent inhibition of FAEE, FAME, and FAA synthesizing activities by TOTP in HepG2 cells suggest that synthesis of FAEEs, FAMEs, and FAAs is catalyzed by the same enzyme(s). However, FAEE, FAME, and FAA synthesizing activities in AR42J cells could not be inhibited by TOTP under similar experimental conditions. A differential pattern of p-nitrophenyl acetate hydrolyzing activity (a measure of esterase activity) similar to that of fatty acid ester/anilide synthesizing activities was observed in the two cell lines. These results are further substantiated by the presence of approximately 60 kDa (subunit molecular weight) protein in the postnuclear fraction of HepG2 but not in AR42J cells by Western blot analysis using antibodies raised against FAEES, purified from rat liver microsomes or adipose tissue. Therefore, the enzyme responsible for the FAEE, FAME, or FAA synthesizing activities is most probably carboxylesterase in HepG2 cells and is structurally and functionally different than that present in AR42J cells. These studies also indicate the utility of HepG2 and AR42J cell cultures as an alternative to the animal model regarding studies on nonoxidative metabolism of alcohols and amines, in general.  相似文献   
75.
To investigate the bacterial etiology of infant diarrhea in Karachi, Pakistan, 180 rectal swab samples collected from diarrhea patients under 5 years of age and 30 samples from age- and sex-matched healthy children were analyzed. Enteropathogenic organisms were isolated from 70 case samples (38.9%). The two most common etiologic agents were Campylobacter jejuni (19.4%) and Aeromonas hydrophilia (6.1%). Salmonella, Shigella, and Yersina appear to have a limited incidence in this age group. None of the control specimens yielded any enteropathogen. Breast-fed infants had a significantly lower risk of enteric infection. A pathogen was isolated in 26.0% of samples from breast-fed children with diarrhea compared with 46.8% of samples from bottle-fed diarrhea patients. All C jejuni infections identified in this study involved bottle-fed children. Boiled water was used to prepare infant formula in only 31.1% of these patients. These findings are consistent with those of other studies showing a decreased rate or severity of diarrhea in breast-fed infants. Mothers should be encouraged to breast feed their infants or, if this is not possible, to use boiled water for the preparation of infant formula.  相似文献   
76.
A strain of CLAVICEPS PURPUREA (F R.) T UL. isolated from ARTHRAXON LANCIFOLIUS H OCHST. was successfully adapted on rye. Experimental cultivation on rye showed 370 kg/ha yield of sclerotia containing 0.5% total alkaloid which consisted of 33% ergometrine, 17.6% ergotamine, 18.7% ergocornine and 22.7% ergokryptine. The results also reveal that alkaloid profile of the ergot strain depends largely on its host. Significantly high yield of the sclerotia and the valuable alkaloid profile of the new strain indicate its commercial potential.  相似文献   
77.
Intravenously administered oxytocin caused a dose-related fall in blood pressure of the rabbit. When oxytocin was administered in oestrogen-primed animals, the depressor response was converted to a pressor one "Oxytocin reversal". The "oxytocin reversal." was abolished after treatment with dihydroergotamine, hexamethonium or adrenalectomy. The "oxytocin reversal" did not appear in reserpinized animals.  相似文献   
78.
PURPOSE: To prospectively compare standard radiation therapy (RT) with an abbreviated course of RT in older patients with glioblastoma multiforme (GBM). PATIENTS AND METHODS: One hundred patients with GBM, age 60 years or older, were randomly assigned after surgery to receive either standard RT (60 Gy in 30 fractions over 6 weeks) or a shorter course of RT (40 Gy in 15 fractions over 3 weeks). The primary end point was overall survival. The secondary end points were proportionate survival at 6 months, health-related quality of life (HRQoL), and corticosteroid requirement. HRQoL was assessed using the Karnofsky performance status (KPS) and Functional Assessment of Cancer Therapy-Brain (FACT-Br). RESULTS: All patients had died at the time of analysis. Overall survival times measured from randomization were similar at 5.1 months for standard RT versus 5.6 months for the shorter course (log-rank test, P =.57). The survival probabilities at 6 months were also similar at 44.7% for standard RT versus 41.7% for the shorter course (lower-bound 95% CI, -13.7). KPS scores varied markedly but were not significantly different between the two groups (Wilcoxon test, P =.63). Low completion rates of the FACT-Br (45%) precluded meaningful comparisons between the two groups. Of patients completing RT as planned, 49% of patients (standard RT) versus 23% required an increase in posttreatment corticosteroid dosage (chi(2) test, P =.02). CONCLUSION: There is no difference in survival between patients receiving standard RT or short-course RT. In view of the similar KPS scores, decreased increment in corticosteroid requirement, and reduced treatment time, the abbreviated course of RT seems to be a reasonable treatment option for older patients with GBM.  相似文献   
79.
We report a case of a 40-year-old man who had presented with a spontaneous suprapubic urinary leak from a well-healed suprapubic cystostomy tract scar, 20 years following a successful scrotal tube substitution urethroplasty done for a post-traumatic urethral stricture. Preoperative contrast studies suggested a recurrent bulbomembranous urethral stricture. Excision biopsy of the suprapubic fistulous tract revealed scar cancer infiltrating the bladder wall. Of 3 similar cases reported in the past, only 1 had bladder involvement. Ours is the second such case with bladder involvement.  相似文献   
80.
BACKGROUND: The aim of this study was to evaluate feasibility and tolerability of the three-drug combination of paclitaxel, ifosfamide and carboplatin (TIC) in patients with advanced non-small-cell lung cancer. The specific objectives of the study were: (i) to define the dose-limiting toxicities (DLTs) and the maximum-tolerated dose of ifosfamide administered as part of the combination; and (ii) to determine the overall response rate and overall survival of patients treated with this regimen. PATIENTS AND METHODS: Patients with untreated, stage IIIB (pleural effusion) or stage IV non-small-cell lung cancer were enrolled in one of three cohorts. Patients received paclitaxel 200 mg/m(2) as a 1-h infusion on day 1 with carboplatin at an area under the concentration-time curve (AUC) of 6 mg.min/ml on day 2. For dose level I, ifosfamide was administered at a dose of 2 g/m(2) on days 1 and 2. For dose levels II and III, the dose of ifosfamide was decreased to 1.5 g/m(2) on days 1 and 2 and the dose of carboplatin was decreased to AUC 5 mg.ml/min. Therapy for dose levels I and III included filgrastim support (5 micro g/kg/day), which was initiated on day 3 and continued until after day 11 or until an absolute neutrophil count >10 000/ micro l. Treatment cycles were repeated every 21 days. Once the phase II dose was established, a full cohort of patients received therapy at this dose level to examine further the regimen's activity and tolerability. RESULTS: Neutropenia was the DLT encountered for dose levels I and II. No DLT was encountered in the initial six patients treated at dose level III, and therefore this dose level was declared the recommended phase II dose. A total of 49 patients were treated at the recommended phase II dose. The predominant non-hematological toxicity encountered with this triplet regimen was cumulative peripheral neuropathy. Of the 65 eligible patients enrolled in this study, 17 (26%) responded. There were 15 patients with partial responses (23%), two with regression, and 26 with stabilization of disease (40%). Median progression-free and overall survival were 4.8 and 9.4 months, respectively. CONCLUSIONS: The combination TIC is well-tolerated. This triplet regimen produced response and survival rates in advanced non-small-cell lung cancer similar to those of other current combination chemotherapy regimens.  相似文献   
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