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51.
52.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society. PAC2003: 8719-j, 8710+e  相似文献   
53.
This study was designed to examine ovarian performance, i.e.follicular growth, normal steroidogenesis and luteal phase function,following the administration of multiple increasing doses ofhuman follicle stimulating hormone (FSH) with a constant lowdose of luteinizing hormone (LH) in women with isolated hypogonadotrophichypogonadism. Human meno–pausal gonadotrophin (HMG) wasused in the first treatment cycle, starting with 150 IU of LHand 150 IU of FSH per day, for 7 days. The dose was increaseddaily with 75 IU of LH and 75 IU of FSH for another 7 days ifno response was detected by serial ultrasound measurements andserumoestradiol determinations. In the second treatment cycle,a constant dose of 75 IU of LH (using HMG) was administeredper day and up to 150 IU of FSH (using urofollitrophin) wassupplemented. If no response was detected after 7 days of treatment,the dose of FSH was increased. For the final stage of ovulationinduction, human chorionic gonadotrophin (HCG) was administeredin the presence of at least one follicle >17 mm in diameterbut with no more than three follicles >16mm in diameter.To verify the adequacy of the luteal phase, a pharmacokinetic/pharmacodynamicstudy of -HCG, oestradiol and progesterone was performed followingthe second treatment cycle only. Ovarian stimulation using aconstant dose of 75 IU of LH and increasing doses of FSH upto 225 IU, resulted in normal follicular growth and hormonalmilieu. Both women showed normal luteal phase oestradiol andprogesterone production and both women conceived following thesecond treatment cycle  相似文献   
54.
This paper presents a policy analysis of the impact of prohibiting Medicaid reimbursement funding for tubal ligations by indigent women, under 21 years of age. Because this population is dependent upon Medicaid funds, the freedom of self determination is limited. The current policy does not provide any alternative to the age rule, even if the patient is infected with a life-threatening disease, such as human immunodeficiency virus (HIV). The policy, therefore, creates serious problems for those individuals who choose to prevent a pregnancy under certain life-threatening circumstances. As the incidence of AIDS continues to increase, the absence of an age alternative for tubal ligations will become a problem of increasing practical and statistical significance. The conceptual framework for the analysis of Medicaid nonreimbursement for tubal ligations, with respect to age demands was adopted from the work of Gilbert and Specht, 1986. Four dimensions of choice are addressed: (1) the bases of social allocation, (2) the nature/type of social provisions, (3) the delivery system and (4) finances. Although all areas will be addressed, the major emphasis will be placed on social allocation.  相似文献   
55.
PURPOSE: Carcinoma of the colon, manifested clinically as an enterococcal hepatic abscess, in the absence of liver metastases, is very uncommon. However, having treated a patient with such a condition, we would like to draw the attention of surgeons to this possibility. Most reports describe secondary infections of hepatic metastases only in patients with a known malignancy. However, increased awareness of colonic cancer as an underlying cause of pyogenic liver abscesses will afford earlier diagnosis and treatment. METHODS: The case was analyzed for history, presentation, laboratory data, radiologic studies, and bacteriology. RESULTS: A 66-year-old woman presented with abdominal pain, fever, and chills. Imaging scans revealed a solitary liver abscess, which was successfully treated with percutaneous drainage and broad-spectrum intravenous antibiotics. Pus cultures grew Streptococcus faecalis.A search for the underlying cause led to the discovery of an adenocarcinoma of the sigmoid colon. CONCLUSIONS: An aggressive search for the underlying cause of pyogenic liver abscesses should be an integral part of the definitive treatment of this disease. After prevailing etiologies have been excluded, silent colonic cancer should be considered.  相似文献   
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Certain modifiable risk factors for cardiovascular disease have their beginnings in childhood. Cigarette smoking, hypertension, physical inactivity, obesity, hypercholesterolemia, hyperinsulinemia, homocysteinemia and poor nutrition in childhood and adolescence may all contribute to the development of cardiovascular disease in adulthood. Identifying at-risk children and adolescents is the first step in modifying or preventing these risk factors. Intervention is most effectively accomplished with an integrated family-oriented approach. Involving the entire family in counseling about interventions to reduce the risk factors for coronary artery disease is important. The family should complete a questionnaire about the family's history and risk of cardiovascular disease. The child, along with other family members, should be given advice on dietary changes to reduce fat intake. Incorporating a cardiovascular health schedule into routine office visits is useful for monitoring the risk of cardiovascular disease and for reinforcing the need to maintain healthy habits.  相似文献   
58.
Pelvic inflammatory disease. Key treatment issues and options.   总被引:6,自引:0,他引:6  
OBJECTIVE.--To examine available data regarding optimal antimicrobial therapy for pelvic inflammatory disease (PID) and to address selected treatment issues confronting clinicians caring for women with PID. DATA SOURCES.--Studies evaluated to help establish the Centers for Disease Control's 1989 Sexually Transmitted Diseases Treatment Guidelines and other reports published since 1985. A MEDLINE search of English-language literature was conducted using the indexing terms "pelvic inflammatory disease" or "pelvic infections" or "salpingitis" and "treatment". In addition, abstracts and bibliographies of articles and books were reviewed. STUDY SELECTION.--Studies were selected for detailed review if they evaluated the effectiveness of an antimicrobial regimen for treatment of PID. DATA EXTRACTION.--All studies were evaluated to determine the numbers of women treated and the percentage with clinical or microbiologic evidence of cure. DATA SYNTHESIS.--A variety of combination antimicrobial regimens are highly effective in providing clinical and microbiologic evidence of cure; few data are available to assess optimal therapy for prevention of late sequelae. Because PID is polymicrobial in cause, recommended antimicrobial regimens are broad-spectrum in coverage. CONCLUSIONS.--No single agent that provides sufficient coverage is currently available. Several combination regimens appear highly effective clinically even among women with tubo-ovarian abscess formation. Uncertainties regarding the effectiveness of antimicrobial therapy for prevention of late sequelae complicate decisions regarding the choice among regimens and the appropriateness of ambulatory treatment of women with PID. Pending better data, hospitalization should be strongly considered, where feasible, particularly for those women with PID desiring further childbearing. Sex partners of all women with PID should be treated.  相似文献   
59.
We studied the effects of intermittent exposure to aflatoxin B1 (AFB1) on hepatic DNA and RNA adduct formation. Fisher-344 male rats were fed 0.01, 0.04, 0.4, or 1.6 ppm of AFB1 intermittently for 8, 12, 16, and 20 weeks, alternating with 4 weeks of dosing and 4 weeks of rest. Other groups of rats were fed 1.6 ppm of AFB1 continuously for 4, 8, 12, and 16 weeks. Control rats received AFB1-free NIH-31 meal diet. AFB1-DNA and -RNA adducts were measured by HPLC with fluorescence detection. The data are presented as total DNA or RNA adducts. The DNA and RNA adduct levels increased or decreased depending on the cycles of dosing and rest. Rats removed from treatment 1 month after 1 or 2 dosing cycles (8 and 16 weeks of intermittent exposure) showed approximately a twofold decrease in DNA adduct levels and a two- to elevenfold decrease in RNA adduct levels compared with rats euthanized immediately after the last dosing cycle (12 and 20 weeks of intermittent exposure). Our data indicate that DNA and RNA adducts increased linearly, from 0.01 ppm to 1.6 ppm of AFB1 after 12 and 20 weeks of intermittent treatment. A linear dose response was also apparent for DNA but not for RNA adducts after 8 and 16 weeks of treatment. As biomarkers of exposure, AFB1-RNA adducts were three to nine times more sensitive than AFB1-DNA adducts but showed greater variability. These results suggest that binding of AFB1 to hepatic DNA is a linear function of the dose, regardless of the way this is administered. The dose-response relationship for RNA adducts depends on the length of the no-dosing cycles and on the turnover rate of RNA.  相似文献   
60.
CONTEXT: Despite advances in early detection and prevention of cervical cancer, women living in rural areas, and particularly in Appalachia, the rural South, the Texas/Mexico border, and the central valley of California, have had consistently higher rates of cervical cancer mortality than their counterparts in other areas during the past several decades. METHODS: This paper reviews the published literature from 1966 to July 2002 to assess three potential pathways underlying this excess mortality--high human papilloma virus (HPV) prevalence, lack of or infrequent screening and advanced disease at diagnosis, and under-use of recommended treatment and shorter survival. FINDINGS: Living in rural areas may impose barriers to cervical cancer control, including lack of transportation and medical care infrastructures. Population characteristics that place women at greater risk for developing and dying from cervical cancer, such as low income, lack of health insurance, and physician availability, are concentrated in rural areas. Published data, however, are insufficient to identify the key reasons for the observed mortality patterns. CONCLUSIONS: At this time, given the lack of definitive evidence in the published literature, decisions about priorities in areas with high rates of cervical cancer mortality will depend on knowledge of current levels of screening, incidence, and stage distribution; and service delivery infrastructures, resources, and acceptability of interventions to the target population.  相似文献   
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