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71.
BACKGROUND: Orthopaedic surgeons working in the Americas may be consulted in the care of patients bitten by venomous rattlesnakes (genus Crotalus ), particularly with regard to the possibilities of compartment syndrome and soft-tissue destruction. Despite considerable evidence regarding the safety and efficacy of antivenin in the treatment of rattlesnake bites in adults, controversy persists regarding the roles of antivenin and surgery in the treatment of rattlesnake envenomations in children. Our hypothesis is that aggressive use of antivenin is just as effective and safe for children as it is for adults. METHODS: We retrospectively reviewed the charts of twenty-four consecutive patients who had been managed at our hospital because of a bite from a western diamondback rattlesnake. Nineteen of the twenty-four patients had been envenomated. The uniformity of collected data was facilitated by the use of an intensive-care-unit protocol during the ten-year period that was reviewed. A questionnaire was developed for long-term follow-up. RESULTS: Aggressive use of polyvalent equine antivenin safely prevented the need for surgery in sixteen of the nineteen envenomated patients. Of the three patients who had surgical treatment, two were managed with limited soft-tissue debridement and one was managed with a fasciotomy of the leg because of a compartment syndrome that occurred when adequate antivenin was withheld. No serious adverse effects were noted in association with the antivenin, and no functional impairments were noted at the time of discharge. CONCLUSION: Antivenin, rather than surgery, is the proper initial treatment of severe rattlesnake envenomations in children.  相似文献   
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73.
Cellular microtubules, polymers of tubulin, alternate relentlessly between phases of growth and shortening. We now show that noscapine, a tubulin-binding agent, increases the time that cellular microtubules spend idle in a paused state. As a result, most mammalian cell types observed arrest in mitosis in the presence of noscapine. We demonstrate that noscapine-treated murine melanoma B16LS9 cells do not arrest in mitosis but rather become polyploid followed by cell death, whereas primary melanocytes reversibly arrest in mitosis and resume a normal cell cycle after noscapine removal. Furthermore, in a syngeneic murine model of established s.c. melanoma, noscapine treatment resulted in an 85% inhibition of tumor volume on day 17 when delivered by gavage compared with untreated animals (P 相似文献   
74.
RATIONALE AND OBJECTIVES: The goal of this study was to evaluate the utility of T1rho weighting in magnetic resonance imaging of murine brain tumors. MATERIALS AND METHODS: S91 Cloudman melanoma was implanted in mouse brains (n = 4). A T2-weighted spin-echo (SE) and a T1rho-weighted fast SE-based sequence were performed on a 4-T clinical imager. T2 and T1rho maps were computed. The tumor-to-normal-tissue contrast was compared between T2-weighted, T1rho-weighted, proton-density-weighted, and pre- and postcontrast T1-weighted SE images. RESULTS: The tumor-tissue contrast of the T1rho-weighted images was similar to that of the T2-weighted images but less than that of the postcontrast T1-weighted images. The T1rho-weighted images provided better definition of tumor boundaries than T2-weighted images. At spin-locking powers of 0.5 and 1.5 kHz, the T1rho of the tumor was 64.0 msec +/- 0.46 and 68.65 msec +/- 0.59, respectively. There was no significant inter- or intra-animal variation in T1rho for tumor or normal brain cortex. CONCLUSION: T1rho-weighted imaging performed at low spin-lock strengths qualitatively depicted tumor borders better than proton-density or T2-weighted imaging and could be useful in treatment planning when combined with other imaging sequences.  相似文献   
75.
Early infantile pertussis; increasingly prevalent and potentially fatal   总被引:1,自引:0,他引:1  
We report nine cases of severe early pertussis in infants less than 7 weeks of age. Clinical features at this age are atypical and may be confused with more common illnesses such as bronchiolitis. All were very difficult to manage. Ventilation was required for apnoeas in five cases, seizures in two or respiratory failure in two. Complications included hypotension in seven cases, pulmonary hypertension in one, pneumothoraces in two, seizures in five and co-infection in five. Two cases were referred for extracorporeal membrane oxygenation and six died. Infection was confirmed either at post mortem or by culture from pernasal swabs. The mother or other close family members were symptomatic at the time and thought to be the source of infection. Conclusion The nine cases suggest a significant resurgence of the infection, which may be fatal in early life. If reporting continues to increase, the immunisation schedule will need to be reviewed and secondary transmission prevented where possible, to protect this vulnerable pre-immunisation group. Received: 5 October 1999 / Accepted: 22 May 2000  相似文献   
76.
Summary Children presenting with pallor, hepatosplenomegaly and other features suggestive of haemolytic disease were investigated for the presence of abnormal haemoglobins. In this effort, 67 cases of thalassaemia major, 118 of, thalassaemia minor, 9 of thalassaemia haemoglobin E disease, 8 of sickle cell anaemia and 98 parents with, the thalassaemia minor trait were detected. None of the cases had migrated from or had ancestors from West Bengal or East Bengal. From the Niloufer Hospital for Women and Children, and the Department of Pediatrics, Osmania Medical College, Hyderabad.  相似文献   
77.
Purpose. The present study was conducted to evaluate theeffects of formulation pH and dose on nasal absorption of scopolaminehydrobromide, the single most effective drug available for the prevention ofnausea and vomiting induced by motion sickness. Methods. Human subjects received scopolamine nasally at adose of 0.2 mg/0.05 mL or 0.4 mg/0.10 mL, blood samples were collected atdifferent time points, and plasma scopolamine concentrations were determinedby LC-MS/MS. Results. Following administration of a 0.2 mg dose, theaverage Cmax values were found to be 262 ± 118, 419± 161, and 488 ± 331 pg/mL for pH 4.0, 7.0, and 9.0formulations, respectively. At the 0.4 mg dose the average Cmaxvalues were found to be 503 ± 199, 933 ± 449, and 1,308± 473 pg/mL for pH 4.0, 7.0, and 9.0 formulations, respectively. At a0.2 mg dose, the AUC values were found to be 23,208 ± 6,824, 29,145± 9,225, and 25,721 ± 5,294 pg.min/mL for formulation pH 4.0,7.0, and 9.0, respectively. At a 0.4 mg dose, the average AUC value wasfound to be high for pH 9.0 formulation (70,740 ± 29,381 pg.min/mL)as compared to those of pH 4.0 (59,573 ± 13,700 pg.min/mL) and pH 7.0(55,298 ± 17,305 pg.min/mL) formulations. Both the Cmaxand AUC values were almost doubled with doubling the dose. On the otherhand, the average Tmax values decreased linearly with a decreasein formulation pH at both doses. For example, at a 0.4 mg dose, the averageTmax values were 26.7 ± 5.8, 15.0 ± 10.0, and 8.8± 2.5 minutes at formulation pH 4.0, 7.0, and 9.0, respectively. Conclusions. Nasal absorption of scopolamine hydrobromidein human subjects increased substantially with increases in formulation pHand dose.  相似文献   
78.
We present a rare case of a myxoid-feature lipoma that arose in the patella fat pad and caused patellar tendon rupture.  相似文献   
79.
Many plants are known to possess antifertility activity. However, limited attempts have been made to scientifically evaluate these claims. Hibiscus rosa-sinensis flowers have been shown to possess antifertility and abortifacient activity. In this report, antiimplantation activity of water extract of leaves of H. rosa-sinensis was investigated. Pregnant female mice were dosed with extract (100 mg/kg body weight) from days 1 to 6 of pregnancy. No implantation sites were observed in treated animals when they were surgically opened on day 15 of pregnancy. Biochemical and biophysical alterations were observed in the endometrium in treated animals, especially on day 5, at 4:40 a.m., the day of implantation. A sharp increase in superoxide anion radical and a sharp fall in superoxide dismutase (SOD) activity, as seen in the endometrium from control animals, were altered in treated animals. The extract also exhibited antiestrogenic activity, as judged by increase in uterine weight. The physiological alterations induced by water extract of H. rosa-sinensis are discussed.  相似文献   
80.
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