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F. R. VOGELPOEL R. J. VAN KOOIJ E. R. TE VELDE J. VERHOEF 《International journal of andrology》1990,13(2):81-86
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous. 相似文献
3.
Image-directed percutaneous biopsies with a biopsy gun 总被引:3,自引:0,他引:3
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献
4.
Group A Streptococcal Antibodies in Subjects with or without Rheumatic Fever in Areas with High or Low Incidences of Rheumatic Fever 下载免费PDF全文
Elia M. Ayoub Beverly Nelson Stanford T. Shulman Douglas J. Barrett J. Douglas Campbell George Armstrong John Lovejoy Gerald H. Angoff Sol Rockenmacher 《Clinical and Vaccine Immunology : CVI》2003,10(5):886-890
The levels of streptococcal antibody titers in populations with or without rheumatic fever from an area with a relatively high incidence of rheumatic fever and an area with a low incidence of this disease were compared. Streptococcal antibody titers were determined for two populations, each of which included children without rheumatic fever (nonrheumatic children) and rheumatic fever patients. The two populations were derived from two separate geographic areas, one with a high incidence of rheumatic fever (Grenada) and another with a low incidence of this disease (central Florida). The results revealed an absence of consistent differences in the geometric mean antibody titers between the nonrheumatic subjects and the rheumatic fever patients from Grenada. In the population from Grenada, the mean anti-streptolysin O and anti-DNase B titers were higher in the nonrheumatic controls (P of 0.085 and 0.029, respectively). However, the mean titer of the antibody to the group A streptococcal cell wall carbohydrate was higher in the rheumatic fever patients than in the nonrheumatic controls (P = 0.047). This finding contrasted with the finding that the means of all three streptococcal antibody titers in the patients with rheumatic fever were significantly higher than those in the nonrheumatic subjects from Florida (P = 0.01-<0.001). The reason for this paradoxical finding became evident when the streptococcal antibody titers of the nonrheumatic subjects from Grenada and Florida were compared, revealing significantly higher levels of all three antibodies in the nonrheumatic subjects from Grenada than in the nonrheumatic subjects from Florida (P < 0.001). These results suggest that nonrheumatic individuals in an area with a high incidence of rheumatic fever have inordinately elevated levels of streptococcal antibodies in serum. The presence of elevated streptococcal antibody titers in such a population, which probably reflects a high background prevalence of streptococcal infections, should be taken into consideration when evaluating the role of the group A streptococcus in nonpurulent complications of infections. 相似文献
5.
Maria A. Serrat C. Owen Lovejoy Donna King 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(4):375-381
The proximal and distal growth plates of the principal long bones do not contribute equally to longitudinal growth. Most forelimb elongation occurs at the shoulder and wrist, while most hindlimb growth occurs at the knee. This study examined whether insulin‐like growth factor‐I (IGF‐I), a potent growth regulator, could underlie this variation via differential receptor expression. The spatiotemporal distribution of the IGF‐I receptor (IGF‐IR) was mapped in hindlimb growth plates (overall and within regional zones) from immature mice using immunohistochemistry. Growth activity was assessed by size/morphology of the growth plate and proliferating cell nuclear antigen (PCNA) expression. Both IGF‐IR and PCNA staining declined considerably with age in the proximal femur and distal tibia (hip and ankle), but expression remained high in the more active distal femur and proximal tibia (knee) throughout growth. Growth plate size decreased with age in all sites, but the absolute and relative decline in IGF‐IR in the hips and ankles of older mice indicated a site‐specific loss of IGF‐I sensitivity in these less active regions. These results suggest that regulation of the IGF‐IR may at least partially mediate differential long bone growth, thereby providing a local mechanism for altering skeletal proportions absent modification of systemic hormone levels. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
6.
J Smith S Lensing J A Horton J Lovejoy S Zaghloul I Forrester B B McGee M L Bogle 《American journal of public health》1999,89(9):1418-1421
OBJECTIVES: The purpose of this study was to assess demographic and geographic differences in prevalence of self-reported nutrition-related health problems in Arkansas, Louisiana, and Mississippi. METHODS: The authors analyzed 1991 and 1993 Behavioral Risk Factor Surveillance System data for adults 18 years or older. RESULTS: Less educated African American women and women of other minority groups who were aged 35 to 64 years reported the highest prevalence of health problems. Geographic differences involved prevalence of hypertension, health status, and insurance status. CONCLUSIONS: Specific demographic subgroups and geographic areas with a high risk of health problems are in particular need of targeted interventions. 相似文献
7.
BACKGROUND: 'Brown bag' medication reviews carried out by community pharmacists collaborating with GPs have become established, in the USA and elsewhere, as an effective means of helping primary care patients to derive maximum benefit from their medicines, of identifying medication-related problems and of reducing wastage of medicines. OBJECTIVE: We aimed to determine whether 'brown bag' medication review could be used successfully in the UK, and particularly whether it represents an efficient and potentially cost-effective means of identifying medication problems. METHOD: 'Brown bag' medication reviews were carried out on 205 volunteer patients in 23 pharmacies in south-east London. Pharmacists' interventions to improve patients' knowledge and usage of their medicines were analysed. Potential clinical problems identified by pharmacists were analysed in order to identify the drug groups most likely to cause problems. RESULTS: Interventions were made in 87% of reviews; interventions to improve patients' knowledge of the purpose and correct usage of their drugs were made in 65% of reviews. In 12% of reviews, problems were identified that could potentially result in a hospital admission, and the potential for an improved outcome for the patient if drug therapy was changed was identified in a further 34% of cases. Beta-blockers, NSAIDs and verapamil were identified as being associated with potential problems of the highest clinical significance. Patients taking psychoactive medication were at greatest risk of a medication-related problem from any cause. CONCLUSION: Pharmacists could contribute to patients' welfare and reduce health care costs by carrying out 'brown bag' medication reviews on behalf of GPs. 相似文献
8.
Abstract A model of analysis incorporating methodological improvements and epidemiological refinements has been employed to investigate the etiology of porotic hyperostosis and periosteal reactions in infants and children from the Libben Site, a Late Woodland ossuary and occupation site from Ottawa County, Ohio. Results of the age-specific intrapopulational analysis of porotic hyperostosis demonstrate that the skeletal lesion strongly fits the age-specific distribution of hypochromic microcytic iron-deficiency anemia in infants and children. The data indicate that the lesion is a response to nutritional stress. Similarly, our findings show that the age-specific distribution of periosteal reactions strongly coincides with, and appears to be a response to, infectious disease as it occurs in infants and children. More importantly, survivorship and growth data indicate that porotic hyperostosis and periosteal reactions are strongly associated with patterns of infant and child morbidity and mortality, and therefore appear to play an important role in selection and fitness at Libben. Based upon the age-specific patterns and associations observed for porotic hyperostosis and periosteal reactions in the Libben infants and children, it is suggested that: 1. the current methodological procedure of partitioning skeletal populations into broad age categories can significantly distort important age-specific pathophysiological relationships; 2. skeletal lesions should be classified according to their physical quality (i.e., remodeled and unremodeled) to provide an estimate of both the morbidity and mortality associated with the age-specific distribution of a particular skeletal lesion; 3. porotic hyperostosis may be a valuable indicator of nutritional stress which can be employed to evaluate the nutritional status of prehistoric human populations; 4. the pathogenesis of porotic hyperostosis can best be understood in terms of the synergistic interactions between constitutional factors, diet, and infectious disease. 相似文献
9.
Although treatment of HIV infections is possible, anecdotal data and research suggest that infected homosexual and bisexual men are developing sets of HIV-specific self-care behaviors that they believe will maintain their health or delay progressive disease. However, little is known about frequent use of HIV self-care in relationship to symptom distress or other factors commonly assessed by nurses. These deficits limit the ability of healthcare providers to intervene appropriately. Consequently, the following repeated-measures study retrospectively examined correlates of HIV self-care in 162 outpatients who were attending a major healthcare facility in San Francisco, CA. Standard and HIV-specific instruments created for the study were used in data collection. Results suggest that the men increased their use of 35 of 81 HIV self-care behaviors once they became aware of being HIV seropositive (p less than 0.001). Frequent use of HIV self-care behaviors was related to several variables, including previous patterns of self-care (p less than 0.001), and AIDS diagnosis (p less than 0.01), and a locus of control (LOC) indicator (e.g., the statement "What happens to me is beyond my control") (p less than 0.001). Symptom distress also was related to several variables, including selected LOC and quality-of-life (QOL) indicators, mood states, and recent diagnosis of selected AIDS-related diseases (p less than 0.01). Collectively, these results suggest that taking self-care and selected psychosocial histories will allow nurses to identify ambulatory patients with HIV infections who need intensive care. 相似文献
10.