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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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1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
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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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Pancreatogastrostomy: a safe drainage procedure after pancreatoduodenectomy   总被引:8,自引:0,他引:8  
R Delcore  J H Thomas  G E Pierce  A S Hermreck 《Surgery》1990,108(4):641-5; discussion 645-7
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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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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