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41.
The disparity in white and African American infant mortality has not only persisted but increased over time and is not expected to diminish in the near future. This article reviews the theoretical and empirical literature on the constellation of class, race, and gender vulnerabilities on African American life as manifested in infant mortality. Utilizing a public health framework, it provides an overview of primary, secondary, and tertiary prevention initiatives within the social work practice domain. Ethnic-sensitive practice perspective for social workers is highlighted and includes empowerment, strengths, Africentric, and advocacy and social action.  相似文献   
42.
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species.  相似文献   
43.
  • 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
  • 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
  • 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
  • 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
  • 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
  • 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
  相似文献   
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Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.  相似文献   
46.
47.
Anti-thrombotic therapy for non-rheumatic atrial fibrillation   总被引:1,自引:0,他引:1  
Recent randomized trials of antithrombotic therapy in non-rheumatic atrial fibrillation have helped to clarify the benefits of warfarin and aspirin. Low-risk patients (normotensives aged <60 with normal left ventricular function) have a small risk of thromboembolic events and are unlikely to benefit significantly from anticoagulants, but may benefit from aspirin with little increase in risk of bleeding. High-risk patients (>75 years, impaired left ventricular function, previous thromboembolism and/or associated conditions such as hypertension and diabetes mellitus) have an increased risk of thromboembolism, and benefit from long-term anticoagulant therapy to a greater degree than with aspirin, although at a risk of increased bleeding complications.   相似文献   
48.
49.
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases.  相似文献   
50.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot.  相似文献   
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