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Pierce A. Grace 《Irish journal of medical science》1997,166(3):152-156
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OBJECTIVE: Laws that prohibit certain individuals from owning firearms also pertain to ammunition. Whereas retail sales of firearms to criminals are regularly disrupted by instant background checks, sales of ammunition are essentially unchecked and the rate at which criminals acquire ammunition is unknown. This research describes the ammunition market and estimates the rate at which criminals are acquiring ammunition. DESIGN: Criminal background checks conducted on individuals purchasing ammunition in the City of Los Angeles in April and May 2004. SETTING: Los Angeles, CA, USA. SUBJECTS: Ammunition purchasers. MAIN OUTCOME MEASURES: Criminal activity that prohibits one from owning, purchasing, or possessing ammunition. RESULTS: 2.6% (95% CI 1.9% to 3.2%) of ammunition purchasers had a prior felony conviction or another condition that prohibited them from possessing ammunition. During the study period prohibited possessors purchased 10,050 rounds of ammunition in Los Angeles. CONCLUSIONS: These estimates suggest that monitoring ammunition transactions may help reduce the supply of ammunition to criminals and the frequency of injuries from felonious gun assaults. Such a record can also provide information for generating leads on illegal firearm possession. 相似文献
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R. Christopher Pierce Amy J. Clemens Laura A. Shapiro George V. Rebec 《Psychopharmacology》1994,116(1):103-109
Acute administration of neuroleptic drugs alters the extracellular level of ascorbate in the neostriatum, and increasing evidence suggests a role for this vitamin in the behavioral, and possibly therapeutic, effects of these drugs. To shed further light on this issue, extracellular ascorbate was recorded in the neostriatum and nucleus accumbens of awake, behaving rats following chronic treatment with either classical (haloperidol) or atypical (clozapine) neuroleptics or ascorbate itself. Electrochemically modified, carbon-fiber microelectrodes were lowered in place the day after the last of 21 daily injections of either haloperidol (0.5 mg/kg, SC), clozapine (20 mg/kg, IP), sodium ascorbate (500 mg/kg, IP) or vehicle. Voltammetric measurements were obtained during quiet rest and following administration ofd-amphetamine (2.5 mg/kg). Repeated treatment with either haloperidol or ascorbate elevated basal extracellular ascorbate and potentiated the amphetamine-induced increase in ascorbate release in neostriatum but not nucleus accumbens. Both treatment groups also showed a significant increase in amphetamine-induced sniffing and repetitive head movements compared to vehicle-treated animals. In contrast, repeated clozapine had no effect on extracellular ascorbate in either neostriatum or nucleus accumbens, but increased the locomotor response to an amphetamine challenge. Thus, to the extent that increases in neostriatal ascorbate exert neuroleptic-like effects, such effects are likely to parallel haloperidol rather than clozapine. 相似文献
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The purpose of this study was to evaluate the role of pancreaticogastrostomy as an alternative method of restoring pancreaticointestinal continuity after pancreaticoduodenectomy. Since 1975, 45 patients have undergone pancreaticogastrostomy after pancreaticoduodenectomy at our institution. Pancreaticoduodenectomy was performed for pancreatic carcinoma (24 patients), ampullary carcinoma (8 patients), duodenal carcinoma (4 patients), common bile duct carcinoma (4 patients), pancreatic islet cell carcinoma (1 patient), trauma (1 patient), extensive colon carcinoma (1 patient), chronic pancreatitis (1 patient), and gastroduodenal artery aneurysm (1 patient). There was one operative death, for an overall operative mortality rate of 2%, and seven patients had major postoperative complications, for an overall morbidity rate of 15%. No pancreatic anastomotic leaks or other complications related to the pancreaticogastrostomy occurred. Twenty-four patients have died of recurrent carcinoma, with a mean survival of 25 months (range, 5 to 66 months), and 20 patients are alive and well, with a mean follow-up of 27 months (range, 2 to 106 months). Eight of these patients are alive 2 or more years after operation and four do not have exocrine pancreatic insufficiency. This experience confirms that pancreaticogastrostomy is a safe method of pancreatic drainage after pancreaticoduodenectomy and suggests that it may have technical advantages and therefore merits more widespread application. 相似文献
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Jay Jegathesan Jennifer A Liebenthal Melinda G Arnett Richard L Clancy Janet D Pierce 《Medsurg nursing》2004,13(6):371-375
Advances in science have increased the knowledge of how cells die in the body (apoptosis). A basic understanding of this process can improve nurses' ability to review new scientific literature and enable them to provide safer bedside care. 相似文献
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Conservative surgery and radiation therapy in black women with early stage breast cancer. Patterns of failure and analysis of outcome. 总被引:3,自引:0,他引:3
Between 1977 and 1986, 75 black and 615 white women with American Joint Committee (AJC) Stages I and II breast cancer were treated with excisional biopsy, axillary dissection, and radiation therapy for breast conservation. Cyclophosphamide, methotrexate, and 5-fluorouracil, with and without prednisone and tamoxifen, was given to 92% of premenopausal, 83% of perimenopausal, and 63% of postmenopausal node-positive women; 20 of 106 (19%) postmenopausal node-positive women received tamoxifen only. The clinical characteristics of the similarly treated patients were compared. The 5-year actuarial local only first failure rate was 5% for black women and 6% for white women (P = 0.53). Regional only failure as the first site of failure was 9% for blacks versus 1% for whites (P = 0.002), with regional recurrence as any component of first failure being 16% for blacks and 4% for whites (P = 0.001). The supraclavicular fossa was identified as the primary site of regional recurrence in black patients with either pathologically positive or negative axillae. Distant metastases as the only site of first failure were significantly greater in the black population with a 20% 5-year actuarial failure rate versus 11% in white patients (P = 0.01). The 5-year actuarial overall survival for the black patients was 82% versus 91% for the white patients (P = 0.01), with no-evidence-of-disease (NED) survival being 64% and 83% (P = 0.0002) and relapse-free survival (RFS) being 61% and 77% (P = 0.01), respectively. Black patients younger than 40 years of age or with pathologically positive axillary nodes had significantly worse NED, RFS, and overall survival compared with similarly staged white patients. Cosmetic results were analyzed at 3 and 5 years after completion of therapy. Although significantly fewer black patients had an excellent-to-good cosmetic result at 3 years compared with white patients, the results were not significantly different at 5 years. These results show that appropriately selected black patients with early stage breast cancer have excellent local control after conservative surgery and radiation therapy and should continue to be offered breast preservation as an alternative to mastectomy. Patterns of failure, however, demonstrated higher regional and distant recurrence rates and lower NED, RFS, and overall survival rates in most subsets of black patients reviewed. 相似文献