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1.
2.
Alikani Mina; Noyes Nicole; Cohen Jacques; Rosenwaks Zev 《Human reproduction (Oxford, England)》1994,9(7):1318-1321
Six cases of identical twin pregnancies which occurred in 2163cycles of in-vitro fertilization during a 3 year period arereported. Monozygosity was confirmed when the number of fetusesexceeded the number of embryos replaced (n = 4) or when twoconcepti were observed in a single amniotic sac (n = 2). Eachof the reported pregnancies resulted from replacement of embryoseither with naturally thin zonae pellucida or embryos whosezonae had been breached during micromanipulation for assistedfertilization (subzonal sperminsertion) or assisted hatching.That such cases exclusively gave rise to monozygosity suggestsa link between the physical state of the zona pellucida, hatching,and generation of identical twins. 相似文献
3.
We have recently demonstrated that the number of small sensory neurons of the A-δ- and C-fiber group in lumbar dorsal root ganglia labeled with horseradish peroxidase (HRP) is selectively decreased 7 days after Nd:YAG laser irradiation of the tibial nerve in the rat. In contrast, the number of large diameter sensory neurons was not affected by laser application. In an attempt to clarify the fate of motoneurons after laser irradiation of their peripheral axons, the numbers of lumbar motoneurons retrogradely labeled with HRP 7 days after Nd:YAG laser irradiation of the tibial nerve have been determined in rats. Our results show that the number of HRP-labeled motoneurons in lumbar segments L6 to L3 is not altered to a significant extent after laser irradiation of their peripheral axons (laser-treated side, 767 ± 10 cells vs control side, 808 ± 19; n = 5, mean ± SEM). In addition, no difference was detected in the mean value or the distribution of soma cross-sectional areas of labeled motoneurons on the laser-treated side and the control side. Specifically, the numbers of HRP-labeled small diameter motoneurons, which are presumably γ in type and have a conduction velocity similar to sensory neurons of the A-δ group, were not affected by laser application. Possible mechanisms of the differential vulnerability of sensory neurons as compared to motoneurons of similar size are discussed. 相似文献
4.
C Callaway C Falcon G Grant D H Maurer A D Auerbach Z Rosenwaks M S Pollack 《Human immunology》1986,16(2):200-204
Like fetal fibroblasts and amniotic fluid cells, cultured chorionic villus cells can also be HLA typed with selected typing sera after preincubation with gamma interferon to promote better antigen expression. A modified procedure now in use would also allow any of these cell types to be tested for the presence or absence of all known HLA A,B,C, and DR antigens with standard preplated typing trays. This procedure was used to confirm that an on-going pregnancy had resulted from the successful in vitro fertilization and implantation of an anonymous donor's ovum and could also be of major use in rape or artificial insemination cases when the identity of the possible father(s) is not known. 相似文献
5.
Detection of sperm in men with Y chromosome microdeletions of the AZFa,AZFb and AZFc regions 总被引:21,自引:0,他引:21
Hopps CV Mielnik A Goldstein M Palermo GD Rosenwaks Z Schlegel PN 《Human reproduction (Oxford, England)》2003,18(8):1660-1665
BACKGROUND: Y chromosome microdeletions are associated with severe male factor infertility. In this study, the success rate of testicular sperm retrieval was determined for men with deletions of AZF regions a, b or c. METHODS: AZF deletions were detected by PCR of 30 sequence-tagged sites within Yq emphasizing the AZFa, b and c regions. Semen analysis and diagnostic testis biopsy or testicular sperm extraction (TESE) findings were correlated with the specific AZF region deleted. RESULTS: A total of 78 men with AZF deletions included three with AZFa deletion, 11 with AZFb, 42 with AZFc, 16 with AZFb+c and six with Yq (AZFa+b+c). All men with AZFa, AZFb, AZFb+c and Yq deletions were azoospermic and no sperm were found with TESE or biopsy. Of men with isolated AZFc deletion, sperm were found in 75% (9/12) by TESE and 45% (9/20) on biopsy (56% overall); 62% (26/42) were azoospermic and 38% (16/42) severely oligozoospermic. A total of 7 patients with deletion patterns that included the complete AZFa region and 23 that included the complete AZFb region who underwent TESE or biopsy did not have sperm detected by these surgical measures. CONCLUSIONS: Microdeletion of the entire AZFa or AZFb regions of the Y chromosome portends an exceptionally poor prognosis for sperm retrieval, whereas the majority of men with AZFc deletion have sperm within the semen or testes available for use in IVF/ICSI. 相似文献
6.
Damario MA; Barmat L; Liu HC; Davis OK; Rosenwaks Z 《Human reproduction (Oxford, England)》1997,12(11):2359-2365
Certain patients have a tendency for high response to gonadotrophin therapy
which is often not ameliorated with prior gonadotrophin- releasing hormone
agonist (GnRHa) suppression. As a result, these patients are frequently
cancelled and often experience ovarian hyperstimulation syndrome (OHSS)
episodes during in-vitro fertilization (IVF)-embryo transfer cycles.
Patients with polycystic ovarian syndrome (PCOS) have been noted to be
particularly sensitive to exogenous gonadotrophin therapy. We have
developed a protocol which is effective in improving IVF outcome in high
responder patients, including those with PCOS. Oral contraceptive pills
(OCP) are taken for 25 days followed by s.c. leuprolide acetate, 1 mg/day,
which is overlapped with the final 5 days of oral contraceptive
administration. Low-dose gonadotrophin stimulation is then initiated on the
third day of withdrawal bleeding in the form of either human menopausal
gonadotrophins or purified urinary follicle-stimulating hormone at a dosage
of 150 IU/day. Over a 5 year period, we reviewed our experience utilizing
this dual method of suppression in 99 cycles obtained in 73 high responder
patients. There were only 13 cancellations prior to embryo transfer
(13.1%). The clinical and ongoing pregnancy rates per initiated cycle were
46.5 and 40.4% respectively. Only eight patients experienced mild-moderate
OHSS following treatment. For those patients who had undergone previous
IVF-embryo transfer cycles at our centre, significant improvements were
noted in oocyte fertilization rates, embryo implantation rates and
clinical/ongoing pregnancy rates with this protocol. Hormonal analyses
revealed that the chief mechanism may be through an improved luteinizing
hormone/follicle-stimulating hormone ratio following dual suppression. An
additional feature of this dual method of suppression is significantly
lower serum androgen concentrations, particularly dehydroepiandrosterone
sulphate.
相似文献
7.
8.
We report here a case of an older woman, 90 years old on admission, who presented with general deterioration, fever, abdominal pain, large hepatic mass, and was found to have an extra-nodal large B-cell lymphoma of the liver. The patient was successfully treated with multi-agent chemotherapy and followed up for 2 years with no recurrence of the disease. To the best of our knowledge this is the oldest patient reported with such a primary extra-nodal hepatic lymphoma and a remarkably favourable response to chemotherapy. 相似文献
9.
Carcinoma of colon presenting as fever of unknown origin 总被引:1,自引:0,他引:1
Agmon-Levin N Ziv-Sokolovsky N Shull P Sthoeger ZM 《The American journal of the medical sciences》2005,329(6):322-326
Fever of unknown origin (FUO) is defined as fever of more than 38.3 degrees C, the cause of which remains elusive after 1 week of intensive investigation. Most cases of FUO are restricted to infections, malignancies, and inflammatory diseases. FUO was previously reported as the presenting symptom of a few solid tumors such as lymphoma, renal cell carcinoma, and hepatocellular carcinoma. Colon carcinoma manifesting as FUO has been rarely reported. We describe three female patients who presented with classical FUO and microcytic anemia. As a control, we retrospectively evaluated 28 matched patients with carcinoma of colon and no fever. The evaluation included review of patient files, clinical and laboratory data, and pathologic specimens. In the three patients (mean age, 58 years) who presented with FUO and had left-sided colon carcinoma and microcytic anemia, pathologic evaluation of the tumor tissues demonstrated a severe organized inflammatory process forming abscesses in the pericolic fat. The 28 control matched patients showed no such histopathologic changes. In patients presenting with FUO, especially those who present with microcytic anemia, even with no bowel disturbances or elevated carcinoembryonic antigen levels, diagnostic workup should include a search for occult colorectal carcinoma. In our three cases, it appears that microabscesses in the pericolic fat are the cause of fever. 相似文献
10.
Sabriya L. Linton Hannah L.?F. Cooper Mary E. Kelley Conny C. Karnes Zev Ross Mary E. Wolfe Don Des Jarlais Salaam Semaan Barbara Tempalski Elizabeth DiNenno Teresa Finlayson Catlainn Sionean Cyprian Wejnert Gabriela Paz-Bailey for the National HIV Behavioral Surveillance Study Group 《American journal of public health》2015,105(12):2457-2465
Objectives. We explored how variance in HIV infection is distributed across multiple geographical scales among people who inject drugs (PWID) in the United States, overall and within racial/ethnic groups.Methods. People who inject drugs (n = 9077) were recruited via respondent-driven sampling from 19 metropolitan statistical areas (MSAs) for the Centers for Disease Control and Prevention’s 2009 National HIV Behavioral Surveillance system. We used multilevel modeling to determine the percentage of variance in HIV infection explained by zip codes, counties, and MSAs where PWID lived, overall and for specific racial/ethnic groups.Results. Collectively, zip codes, counties, and MSAs explained 29% of variance in HIV infection. Within specific racial/ethnic groups, all 3 scales explained variance in HIV infection among non-Hispanic/Latino White PWID (4.3%, 0.2%, and 7.5%, respectively), MSAs explained variance among Hispanic/Latino PWID (10.1%), and counties explained variance among non-Hispanic/Latino Black PWID (6.9%).Conclusions. Exposure to potential determinants of HIV infection at zip codes, counties, and MSAs may vary for different racial/ethnic groups of PWID, and may reveal opportunities to identify and ameliorate intraracial inequities in exposure to determinants of HIV infection at these geographical scales.Since the mid-1990s, there has been an increase in studies evaluating whether features of the social, economic, physical, and political environment (i.e., place characteristics) affect health. This focus on place characteristics is evident in the development of theories conceptualizing place characteristics as health determinants,1–3 in the use of geospatial and systematic social observation methods to measure place characteristics,4–10 in the application of multilevel modeling to assess the potential impacts of place characteristics,11–18 and in the recognition that interventions should not solely encourage individual behavior change but also modify environmental features.3,16,19Literature emerging from this field of research demonstrates that place characteristics operationalized at different geographical scales influence psychosocial processes and individual behaviors that increase vulnerability to several health outcomes. With rare exception,20–24 however, studies of place and health typically assess the potential influence of place characteristics at a single geographical scale and do not simultaneously evaluate characteristics of other geographical scales. For example, several studies, including our own,25,26 sample participants from a single metropolitan statistical area (MSA) to assess the relationships of census tract characteristics to health, without sampling participants from multiple MSAs to simultaneously assess the relationships of tract-, county-, and MSA-level characteristics to health.25–32 The decision to focus on characteristics of a single geographical scale may arise because of data availability, cost constraints, or feasibility.Studies of place and health that focus on a single geographical scale, however, may misspecify relationships and hinder the exploration of causal pathways in 2 ways. First, studies that focus on features measured at a single geographical scale may overlook potential health determinants that are operationalized at other geographical scales. For instance, research assessing the relationships of features of neighborhoods (e.g., economic deprivation, racial/ethnic composition, policing practices, and “crackdowns”) cannot determine the influence of policies, laws, and governmental expenditures that are operationalized at county, MSA, and state levels, and shape neighborhood environments. Second, studies of features of a single geographical scale cannot determine whether relationships between characteristics operating at one geographical scale are confounded, mediated, or modified by characteristics of other geographic scales.3,16,33 The possibility that at least 1 of these mechanisms can occur has been demonstrated in research conducted by Warner and Gomez, which suggests that, among Black women diagnosed with breast cancer, residing in census blocks with high concentrations of Black residents is more protective against mortality in more racially segregated metropolitan areas than less racially segregated metropolitan areas.34In addition, research assessing the association of place-based factors with health outcomes rarely highlights the extent to which variance in health outcomes is explained by place and place-based factors. Determining whether health outcomes vary geographically can generate hypotheses about inequities in exposure to potential place-based determinants of health, and thereby inform how interventions and social policies are developed and spatially concentrated.35The present study illustrates the generative possibilities of extending research beyond a single geographical scale by achieving 2 primary aims. The study’s first aim is to determine the share of total variance in HIV infection that is apportioned to zip codes, counties, and MSAs among people who inject drugs (PWID). In the United States, PWID account for 22% of people living with HIV,36 and a growing body of literature demonstrates that features of neighborhoods such as census-tract racial composition and block-level social or physical disorder are associated with HIV-related outcomes among PWID,37,38 as are features of MSAs, including drug-related law enforcement, income inequality, residential segregation, and health service access.39–41 Revealing the geographical scale to which variance in HIV infection is apportioned among PWID can stimulate hypotheses about inequities in exposure to place-based determinants of HIV and inform the development and tailoring of place-based interventions. For example, finding high MSA-level variance in HIV infection may support analyses of whether MSA-level variations in health care service access predict variance in HIV serostatus and, if they do, support interventions to increase health care access in low-access MSAs. In contrast, if little to no variance in HIV infection among PWID is apportioned to MSAs, PWID may encounter a relatively uniform exposure to health care service access.Previous studies have found that variance in some health outcomes vary across racial/ethnic groups.42,43 The second aim of this study therefore tests the hypothesis that variance in HIV infection will differ within each of 3 racial/ethnic groups of PWID: non-Hispanic/Latino Whites, non-Hispanic/Latino Blacks, and Hispanics/Latinos. 相似文献