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41.
Although a formal public health surveillance system has not yet been established in Latin America to document the attitudes of young people toward sex education, sexual activity, and contraception and their behaviors in these areas, representative data are available from 12 household-based Young Adult Reproductive Health Surveys conducted in seven countries since 1985. The surveys indicate that the rate of sexual experience before marriage or consensual union for males is much higher than that for females, and first sexual experience occurs at a younger age for males than for females. However, from 34% to 90% of females 20-24 years of age report having had premarital sexual relations. No more than 41% of females and 31% of males report that they or their partner used contraception at first sexual experience. Less than one-third of both young men and young women could identify the most fertile period during the menstrual cycle. The results of such surveys have provided program officials and policymakers with data to plan, implement, and evaluate interventions targeted for young adults.  相似文献   
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We evaluated the sensitivity and specificity of positron emission tomography for diagnosis of probable Alzheimer's disease under conditions similar to those encountered in the routine clinical practice of nuclear medicine. We obtained tomographic images of regional cerebral blood flow from three groups of subjects: (1) 13 subjects, ages 69 to 84, who had probable Alzheimer's disease diagnosed by validated clinical criteria; (2) 15 subjects, ages 57 to 77, who had Parkinson's disease without dementia; and (3) 11 subjects, ages 65 to 83, who were normal. Three blinded reviewers, who had not previously seen the images, categorized them as normal, bilateral temporoparietal flow defects typical of Alzheimer's disease, or other abnormality. Consensus interpretation demonstrated sensitivity of 0.38 (5/13) and specificity of 0.88 (23/26) for identifying patients with probable Alzheimer's disease. Thus, the criterion of bilateral temporoparietal reduction in cerebral blood flow used in this study did not have sufficient sensitivity to be of clinical value. While other criteria may be developed to improve diagnostic accuracy, clinical utility can be established only by testing for validity in patients with a full spectrum of complicating neurologic and psychiatric conditions for whom diagnosis is uncertain and who are then followed longitudinally to determine clinical outcome or pathologic findings.  相似文献   
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Base deficit stratifies mortality and determines therapy.   总被引:29,自引:0,他引:29  
OBJECTIVE: To determine the association of base deficit with mortality and other factors affecting mortality. DESIGN: Retrospective review. SETTING: Tertiary care center. PARTICIPANTS: Consecutive samples of 3791 trauma patients admitted with an arterial blood gas sample taken in the first 24 hours. MAIN OUTCOME MEASURES: Age, injury mechanism, head injury, shock (systolic blood pressure less than 90 mm Hg), Revised Trauma Score, TRISS probability of survival Ps, and mortality. RESULTS: Most (3038) patients (80.1%) exhibited a base deficit. Base deficit, age, injury mechanism, and head injury were associated with mortality using logistic regression. Age less than 55 years, no head injury, and a base deficit of -15 mmol/L were associated with 25% mortality. Age greater than or equal to 55 years with no head injury or age less than 55 years with a head injury and a base deficit of -8 mmol/L were associated with a 25% mortality. When shock was added to the model, all factors remained significant, and base deficit was supplemental to blood pressure. Base deficit also added significantly to the Revised Trauma Score and TRISS measurements. CONCLUSIONS: The base deficit is an expedient and sensitive measure of both the degree and the duration of inadequate perfusion. It is useful as a clinical tool and enhances the predictive ability of both the Revised Trauma Score and TRISS.  相似文献   
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Concentrations of metabolites and immunoreactive insulin (IRI) and activities of enzymes related to energy metabolism were measured in plasma of Korean and Japanese beef cattle, which were raised by the indoor feeding system programmed to feed larger amount of roughage in their growing periods and larger amount of concentrate diet in their finishing periods (Japanese feeding system), and grazing New Zealand beef cattle. By the Japanese beef grading system, Korean and Japanese beef cattle showed high beef quality score, average grade 3.3 and 3.6, respectively. The plasma free fatty acid and lactate concentrations and lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and aspartate aminotransferase (AST) activities in Korean beef cattle were significantly higher than those in Japanese beef cattle. The plasma lactate concentration in Korean beef cattle was 8.40 mmol/l, which was similar to the values observed in lactic acidosis. The higher activities of plasma LDH, MDH and AST may indicate slight liver damage by slightly acidotic conditions in Korean beef cattle. New Zealand beef cattle fed on pasture which they harvest by grazing showed significantly lower plasma glucose, cholesterol, lactate and IRI concentrations and enzyme activities than those in Korean and Japanese beef cattle fed on larger amount of concentrate diets. Plasma metabolite concentrations and energy metabolism‐related enzyme activities may be good indicators for evaluating metabolic conditions of beef cattle raised by different feeding systems.  相似文献   
48.
Elevations of epidermal growth factor (EGF) and Ca2+ concentrations in the wound site are associated with reepithelialization during wound healing. In addition, Ca2+ and EGF can both induce increases in matrix metalloproteinase‐9 (MMP‐9) synthesis. However, little is known about the interplay of these events in regulating the migration properties of primary keratinocytes on collagen I, the most abundant extracellular matrix component in the skin. We found that EGF stimulated both chemokinetic and chemotactic migration of primary keratinocytes on collagen I; however, MMP‐9 was required for EGF‐stimulated chemotaxis but not EGF‐stimulated chemokinesis. Calcium at 0.5 mM stimulated chemokinetic migration of keratinocytes. Together, Ca2+ and EGF stimulated higher levels of chemokinesis than either stimulus alone. Furthermore, Ca2+ could restore the ability of keratinocytes from MMP‐9 null mice to undergo EGF‐stimulated chemotaxis. The phosphatidylinositol‐3 kinase inhibitor LY294002 inhibited both EGF‐ and Ca2+‐stimulated chemokinetic migration. In contrast, the MEK inhibitor PD98059 blocked Ca2+‐ but not EGF‐stimulated chemokinetic migration of keratinocytes. A combination of PD98059 and LY294002 was required to inhibit Ca2+ enhancement of EGF‐stimulated migration completely. Calcium‐stimulated chemokinesis was completely blocked by either the protein kinase C‐α inhibitor Gö6976 or the src/fyn inhibitor PP2. Using primary keratinocytes, our results showed how the combined action of Ca2+, EGF, and MMP‐9 regulated the contributions of extracellular‐regulated kinase and phosphatidylinositol‐3 kinase toward chemokinetic and chemotactic migration of keratinocytes.  相似文献   
49.
We report 3 siblings (1 male and 2 female) recently diagnosed with congenital disorder of glycosylation type Ia (CDG-Ia) in their mid-20s. They experience mild mental retardation but manage to function independently in society. Their professions are library assistant, professional artistic painter and secretarial work. All three siblings have cerebellar hypoplasia and ataxia, but are able to ambulate easily. Two of the siblings have required strabismus surgical repairs. All have antithrombin III deficiency, osteoporosis, and mild dysmorphic features. Hypergonadotrophic hypogonadism was a feature of the two female siblings. A type 1 sialotransferrin pattern and phosphomannomutase (PMM) deficiency have been demonstrated. They are compound heterozygotes for R141H and L32R mutations in the PMM2 gene. While there is clinical heterogeneity in CDG-Ia, we believe that our patients are among the mildest of intellectually affected CDG-Ia patients reported to date.  相似文献   
50.
Ovarian hyperstimulation syndrome (OHSS) is a serious complicationof gonadotrophin usage but it is difficult to accurately predictits occurrence. Previous investigators have identified the combinationof high oestradiol concentrations and oocyte number as beingpredictive in 80% of cases. In this study we sought to identifythe incidence of severe OHSS in patients with high oestradiolconcentrations and large numbers of oocytes and to evaluatethe importance of pregnancy in the development of OHSS. Between1990 and 1993, we studied 139 cycles using two assisted reproductivetechniques [oocyte donor, n =72; in-vitro fertilization (IVF),n = 67] in which either oestradiol (>4000 pg/ml), oocytenumber (>25), or both were elevated. OHSS was diagnosed bystandard criteria. There were no cases of severe OHSS in theoocyte donor group and six in the IVF group. Among 10 patientswith oestradiol concentration >6000 pg/ml and >30 oocytes,only one had OHSS (10%). The relative risk of OHSS with pregnancywas 12 (confidence interval 2.18–66.14). We conclude thatthe risk of OHSS even at high levels of stimulation is lowerthan previously believed. Secondly, donors have a very low riskof OHSS, probably because of the absence of pregnancy. As such,cryopreservation of all oocytes in IVF cycles is a reasonablealternative to cycle cancellation or use of adjunctive medication.  相似文献   
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