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991.
Background : The current spectrum of penetrating trauma presenting to Auckland Hospital is described and whether this differs from the situation in 1983 is determined. Methods : Prospectively collected trauma registry data were used to describe the characteristics of penetrating trauma cases presenting to Auckland Hospital during the 1995 calendar year. Using data collected from a previous study in 1983, comparisons were made of the incidence, severity, and outcome of penetrating trauma cases between these two cohorts. Results : In 1995, 96 patients, representing 7.3% of total trauma admissions, presented to Auckland Hospital following penetrating trauma. Of these, 32 patients were admitted by the trauma team via the resuscitation room, 13 were admitted to the intensive care unit (ICU) and four died. The median age of these patients was 30 years and median Injury Severity Score, 4. In comparison with the 1983 patients there was no demonstrable change in the numbers of patients or their length of stay. Although injury severity was similar in the 1995 cohort, fewer patients were admitted to the ICU. Mortality of the ‘trauma team’ group was 4/32 in 1995 compared with 7/33 in 1983. Conclusions : Despite public concerns, the frequency of penetrating trauma cases presenting to Auckland Hospital was similar in 1995 and 1983. There is a non-significant decrease in length of stay and mortality in the 1995 cohort.  相似文献   
992.
Abstract: Excessive distension of venous grafts due to arterial pressure enhances the convective water transport (filtration flow) through the vessel wall, and thus might affect the infiltration of macromolecules such as lipoproteins. In this paired experimental study, filtration velocities were measured at 100 mm Hg for canine jugular veins with or without external supports of expanded poly-tetrafluoroethylene (ePTFE) arterial prostheses. In addition, to assess the effect of filtration velocity on lipid infiltration or uptake, canine jugular veins were wrapped over half of their lengths with ePTFE arterial prostheses and perfused with dog serum containing 3H-cholesterol at a pressure of 100 mm Hg. At 100 mm Hg, the average filtration velocity of the wrapped jugular veins was 7.9 ± 1.3 ± 10-6 cm/s whereas the average filtration velocity of the unwrapped veins was 27.3 ± 2.7 ± 10-6 cm/s (p < 0.005). Moreover, the unwrapped veins had a significantly higher uptake rate of labeled cholesterol than the wrapped veins (10.9 ± 7.3 ± 10-4 cm/h and 5.0 ± 1.6 ± 10-4 cm/h, respectively, p < 0.005). In conclusion, under arterial pressure, veins experience excessive distention, which leads to significant increases in both filtration flow and cholesterol uptake. An external wrap or support of ePTFE material protects veins from excessive distension and thus may prevent atherosclerosis in venous grafts by reducing cholesterol uptake.  相似文献   
993.
Chronic alcohol dependence produces persistent amenorrhea in alcoholic women and female Macaque monkeys but the mechanism is unknown. In one amenorrheic alcohol-dependent monkey, prolactin levels increased from 16.5 to 63 ng/ml during chronic, high-dose alcohol self-administration (3.4 g/kg/day) and immunocytochemical examination of the anterior pituitary showed apparent hyperplasia of the lactotrophs. These data suggested that hyperprolactinemia might contribute to alcohol-induced amenorrhea. Four amenorrheic cycles (85-194 days) from two other alcoholic female monkeys that self-administered an average of 2.97 to 4.4 g/kg/day of alcohol were also studied. Each monkey became amenorrheic during the first menstrual cycle that alcohol was available. One monkey developed galactorrhea during a 97-day amenorrheic cycle when alcohol self-administration averaged 3.35 g/kg/day. Although prolactin levels were intermittently elevated above 20 ng/ml, average levels during these amenorrheic cycles (14.7 +/- 1.8 to 19.6 +/- 1.5 ng/ml) did not differ significantly from prolactin levels during normal ovulatory menstrual cycles when no alcohol was available (19.7 +/- 0.36 ng/ml). There was a negative correlation between daily alcohol dose and prolactin levels (p less than .01). High-dose alcohol self-administration was often associated with low normal prolactin levels, but a relative fall in alcohol dose was usually associated with elevated prolactin levels. These data suggest that both alcohol intoxication and relative alcohol withdrawal may alter basal prolactin levels. LH levels were significantly lower during amenorrheic cycles (16.9 +/- 1.2 to 24 +/- 1.4 ng/ml) than during nonalcohol control cycles (28 +/- 1.2 to 30 +/- 2.2 ng/ml) (p less than .001). These data are consistent with clinical data that suggest that hypothalamic amenorrhea is associated with suppression of gonadotropin secretory activity.  相似文献   
994.
In vivo radionuclide crossmatch is a method for identifying compatible blood for transfusion when allo- or autoantibodies preclude the use of conventional crossmatching techniques. A technique for labeling small volumes of donor red blood cells with [113mIn]tropolone is reported. The use of 113mIn minimizes the accumulation of background radioactivity and the radiation dose especially so when multiple crossmatches are performed. Labeling red cells with [113mIn]tropolone is faster and easier to perform than with other radionuclides. Consistently high labeling efficiencies are obtained and minimal 113mIn activity elutes from the labeled red blood cells. A case study involving 22 crossmatches is presented to demonstrate the technique. The radiation dose equivalent from 113mIn is significantly less than with other radionuclides that may be used to label red cells.  相似文献   
995.
A case of torsion of the vermiform appendix is described. It is a rare cause of an acute abdomen with a clinical presentation that is indistinguishable from acute appendicitis.  相似文献   
996.
The histidine utilization genes hutH and hutU of Pseudomonas putida ATCC 12633 have been mapped by interrupted mating and transduction to a location at approximately 43 minutes on the chromosome, closely linked to ser-800 and met-400 markers previously shown to be at 46 and 42 minutes, respectively. Since restriction enzyme mapping and cloning results have established that all genes associated with the hut pathway are contiguous, earlier maps of this strain which place these genes near 10 minutes on the chromosome in a superoperonic catabolic cluster are in error.  相似文献   
997.
Three inhibitors of the release or effects of endothelium-derived relaxing factor (EDRF), N-nitro-L-arginine, methylene blue and oxyhemoglobin, caused further increases in perfusion pressure during vascular constriction with submaximal concentrations of the thromboxane A2-mimetic, U46619 in fetal vessels of human placental lobules perfused in vitro. The results suggest the EDRF, released during constriction of fetal placental vessels in response to thromboxane A2 receptor stimulation, attenuates the vasoconstrictor response. Hence, impairment of EDRF release or function could contribute to the reduced placental blood flow observed in various disease states associated with increased thromboxane A2 production such as pre-eclampsia.  相似文献   
998.
Three cases are reported of pyogenic (non-tuberculous) myositis involving the ilio-psoas and/or iliacus muscles in children presenting to John Hunter Hospital, Newcastle, Australia, in a 12-month period. In one, cultures grew Haemophilus influenzae type B and in the other two Staphylococcus aureus was isolated. Biopsy of the abscess cavity from the second child confirmed an antecedent haematoma as the underlying cause. The third had underlying sacroiliac septic arthritis with a history of antecedent trauma. The classification, investigation, and treatment of myositis is discussed.  相似文献   
999.
Intra-compartment pressure studies remain the main investigative method in diagnosing chronic compartment syndrome (CCS). Standard exercise protocols have been used to cause the raise in pressure measured in the laboratories. This case suggests that CCS cannot be excluded without the specific sports activity being used to raise the intracompartmental pressure.  相似文献   
1000.
Axillary lymph node status is important in the staging of breast carcinoma. To evaluate the accuracy of technetium-99m sestamibi breast scintigraphy in detecting metastatic axillary lymph nodes as compared with other accepted imaging modalities, we performed99mTc-sestamibi breast scintigraphy, conventional mammography and ultrasound in 36 patients with primary untreated breast carcinoma. With histopathology as the gold standard,99mTc-sestamibi breast scintigraphy was found to yield true-positive results in 7 of 11 cases (64%) of axillary lymph node metastases and true-negative results in 18 of 20 cases (90%); it has an accuracy of 81%, a positive predictive value of 77.8% and a negative predictive value of 81.8%.  相似文献   
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