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51.
A cross-sectional evaluation of dental caries in primary teeth and nutritional status was conducted involving 285 Peruvian children from low socioeconomic conditions aged 3-9 y. Forty-nine percent of the children were found to be chronically malnourished (stunted) whereas acute malnutrition (wasting) was infrequent (2%). Stunted children showed a delayed exfoliation of primary teeth. The caries prevalence curve as a function of age (ie, a plot of decayed, extracted, and filled teeth vs age) was found to be shifted to the right by approximately 15 mo in stunted children as compared with well-nourished children. Children aged 7-9 y with stunted growth showed a significantly higher percentage of carious teeth than did well-nourished children of the same age (40 and 29%, respectively; p less than 0.005). Nutritional deficits that lead to chronic malnutrition not only may affect tooth exfoliation but also appear to render the primary teeth more susceptible to caries attack later in life.  相似文献   
52.
Asian countries account for approximately 60% of the world's suicides, but there is a great mismatch in the region between the scale of the problem and the resources available to tackle it. Despite certain commonalities, the continent itself is culturally, economically, and socially diverse. This paper reviews current epidemiologic patterns of suicide, including suicide trends, sociodemographic factors, urban/rural living, suicide methods, sociocultural religious influences, and risk and protective factors in Asia, as well as their implications. The observed epidemiologic distributions of suicides reflect complex interplays among the traditional value/culture system, rapid economic transitions under market globalization, availability/desirability of suicide methods, and sociocultural permission/prohibitions regarding suicides. In general, compared with Western countries, Asian countries still have a higher average suicide rate, lower male-to-female suicide gender ratio, and higher elderly-to-general-population suicide ratios. The role of mental illness in suicide is not as important as that in Western countries. In contrast, aggravated by access to lethal means in Asia (e.g., pesticide poisoning and jumping), acute life stress (e.g., family conflicts, job and financial security issues) plays a more important role than it does in Western countries. Some promising suicide prevention programs in Asia are illustrated. Considering the specific socioeconomic and cultural aspects of the region, community-based suicide intervention programs integrating multiple layers of intervention targets may be the most feasible and cost-effective strategy in Asia, with its populous areas and limited resources.  相似文献   
53.
Delayed graft function secondary to ischemia/reperfusion injury has been shown to be associated with increased rate of allograft failure following kidney transplantation. Previously, we have shown that chronic lithium pretreatment protects kidney against ischemia/reperfusion injury. In the present study we aimed to examine the effects of acute lithium administration on the renal ischemia/reperfusion injury in rat. Ischemia/reperfusion injury was induced by clamping left renal pedicle for 60 min, two weeks after right nephrectomy. The mechanism of lithium-mediated renoprotection was explored by combined use of lithium and nitro-l-arginine methyl ester (L-NAME) (non-selective nitric oxide synthase inhibitor) and/or indomethacin (non-selective cyclooxygenase pathway inhibitor). Lithium-treated animals were given 40 mg/kg lithium chloride intraperitoneally, 30 min before ischemia. To investigate the role of nitric oxide and cyclooxygenase pathways in renoprotective effect of lithium, L-NAME and/or indomethacin were administered before lithium injection. Serum creatinine, blood urea nitrogen, and renal histology were assessed after 24h of reperfusion. Lithium preconditioning significantly reduced creatinine and blood urea nitrogen (P<0.001) and improved renal histology. Administration of L-NAME completely reversed renoprotective effect of lithium. In contrast indomethacin significantly potentiated the lithium renoprotection. Moreover, co-administration of L-NAME and indomethacin completely abolished the protective effects of lithium. The results show that a single dose of lithium significantly improves renal function following ischemia/reperfusion injury. In conclusion, the ability of lithium to enhance renal tissue tolerance against ischemia/reperfusion injury suggests a potential clinical application in the setting of kidney transplantation. However, more detailed investigations are required before any definite conclusion.  相似文献   
54.

Objective

The Paducah Gaseous Diffusion Plant (PGDP) became operational in 1952; it is located in the western part of Kentucky. We conducted a mortality study for adverse health effects that workers may have suffered while working at the plant, including exposures to chemicals.

Materials and Methods

We studied a cohort of 6820 workers at the PGDP for the period 1953 to 2003; there were a total of 1672 deaths to cohort members. Trichloroethylene (TCE) is a specific concern for this workforce; exposure to TCE occurred primarily in departments that clean the process equipment. The Life Table Analysis System (LTAS) program developed by NIOSH was used to calculate the standardized mortality ratios for the worker cohort and standardized rate ratio relative to exposure to TCE (the U.S. population is the referent for ageadjustment). LTAS calculated a significantly low overall SMR for these workers of 0.76 (95% CI: 0.72–0.79). A further review of three major cancers of interest to Kentucky produced significantly low SMR for trachea, bronchus, lung cancer (0.75, 95% CI: 0.72–0.79) and high SMR for Non-Hodgkin’s lymphoma (NHL) (1.49, 95% CI: 1.02–2.10).

Results

No significant SMR was observed for leukemia and no significant SRRs were observed for any disease. Both the leukemia and lung cancer results were examined and determined to reflect regional mortality patterns. However, the Non-Hodgkin’s Lymphoma finding suggests a curious amplification when living cases are included with the mortality experience.

Conclusions

Further examination is recommended of this recurrent finding from all three U.S. Gaseous Diffusion plants.  相似文献   
55.
56.
BACKGROUND: Current clinical guidelines require that five indices (total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, and the total/HDL cholesterol ratio) be measured or calculated to assess the lipid-related risk of vascular disease. All five are also targets of therapy and therefore all must be measured initially and at follow-up. Considerable evidence indicates that apolipoprotein B (apo B) is a better index of reaching or not reaching treatment targets than total or LDL cholesterol. METHODS: The objective of this study was to examine whether measurement of a single marker (apo B) led to the same categorization of risk as the traditional five indices (lipid profile). If both apo B and lipid profile indicated that the patient was either within or outside their respective treatment targets, the indices were considered concordant. If not, the indices were considered discordant. Concordance/discordance was examined in 215 patients at their first and last clinic visit. RESULTS: Concordance was high in both higher (88% at the first and 92% at the last clinic visit) and lower (76% at the first and 78% at the last clinic visit) risk groups at both the initial and final visits. Discordance was virtually restricted to the group with hypertriglyceridemia with normal concentrations of apo B, a group in which little independent evidence points to any substantially increased risk of vascular disease. CONCLUSIONS: These data raise the possibility that at least for high risk patients treated with statins, follow-up could be simplified and expenses reduced if only apo B were measured. They also raise the possibility that outcome might be improved if the therapeutic algorithm were simplified.  相似文献   
57.
58.
BACKGROUND: Placement of electrophysiology catheters and pacing leads in the coronary sinus is challenging in some patients, particularly those with dilated cardiomyopathy. We hypothesized that cannulation of the coronary sinus and its branches can be facilitated by direct visualization. This study reports our experience with navigation into and within the coronary sinus in a closed-chest animal preparation, using a flexible steerable fiberoptic infrared endoscope that allows visualization through flowing blood. OBJECTIVES: The purpose of this study was to assess the feasibility of direct visualization of endocardial structures through infrared endoscopy. METHODS: Internal jugular venous access was obtained in 10 healthy mongrel dogs (weight 35-45 kg). The infrared endoscope (2900 fiber imaging bundle, wavelength 1,620 nm, frame rate 10-30/s, 320 x 256 pixels) was advanced to the coronary sinus ostium and branches by direct visualization of anatomic landmarks, such as the tricuspid valve and inferior vena cava. Localization was confirmed by fluoroscopy, contrast injection, and pathologic examination. RESULTS: Structures such as the tricuspid valve and inferior vena cava were visualized at distances of 1 to 2 cm, allowing successful coronary sinus identification and engagement in all 10 dogs. Coronary sinus branch images closely resembled pathologic findings. CONCLUSION: Direct visualization of the coronary sinus ostium and branches is possible through infrared endoscopy. This technique likely will facilitate coronary sinus engagement and navigation for pacing lead and catheter placement.  相似文献   
59.
Normal aging causes a decline in object recognition. Importantly, lesions of the perirhinal cortex produce similar deficits and also lead to object discrimination impairments when the test objects share common features, suggesting that the perirhinal cortex participates in perceptual discrimination. The current experiments investigated the ability of young and aged animals to distinguish between objects that shared features with tasks with limited mnemonic demands. In the first experiment, young and old rats performed a variant of the spontaneous object recognition task in which there was a minimal delay between the sample and the test phase. When the test objects did not share any features ("Easy" perceptual discrimination) both young and aged rats correctly identified the novel object. When the test objects contained overlapping features, however, only the young rats showed an exploratory preference for the novel object. In Experiment 2, young and aged monkeys were tested on an object discrimination task. When the object pairs were dissimilar, both the young and aged monkeys learned to select the rewarded object quickly. In contrast, when LEGOs? were used to create object pairs with overlapping features, the aged monkeys took significantly longer than did the young animals to learn to discriminate between the rewarded and the unrewarded object. Together, these data indicate that behaviors requiring the perirhinal cortex are disrupted in advanced age, and suggest that at least some of these impairments may be explained by changes in high-level perceptual processing in advanced age.  相似文献   
60.

Background

The role of ischemia/reperfusion injury in the pathogenesis of acute pancreatitis is still ill-defined. It is accepted, however, that ischemia/reperfusion induces the development of postimplantation pancreatitis that is responsible for considerable morbidity. Preconditioning by brief exposure to ischemia protects the organ against damage evoked by subsequent severe ischemia. This study was undertaken to examine whether two brief ischemic periods protect the pancreas against severe ischemia/reperfusion-induced pancreatitis.

Materials and methods

This study was performed on 30 rats in three groups. The first group (control) underwent a laparatomy without clamping of any artery. The second group underwent 30-minute clamping of the inferior splenic artery followed by 1-hour reperfusion of the pancreas, and the third group underwent clamping of inferior splenic artery (2 × 5 minutes with 5-minute interval) as ischemic preconditioning and then 30-minute clamping of inferior splenic artery followed by 1-hour reperfusion.

Results

Exposure to 30-minute pancreatic ischemia followed by 1-hour reperfusion led to the development of severe alterations greater than the other group that underwent ischemic preconditioning and then ischemia/reperfusion. Ischemia preconditioning applied prior to induction of pancreatitis reduced plasma lipase and interleukin-1β concentrations as well as less histological signs of pancreatic damage.

Conclusion

We concluded that pancreatic ischemic preconditioning reduced the severity of ischemia/reperfusion-induced pancreatitis. This effect seemed to be related at least in part to the release of the proinflammatory mediator interleukin-1β.  相似文献   
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