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41.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
42.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
43.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
44.
Rachel Rabin Yoel Hirsch Martin M. Johansson Joseph Ekstein David A. Zeevi Beth Keena Elaine H. Zackai John Pappas 《American journal of medical genetics. Part A》2019,179(10):2144-2151
Warsaw breakage syndrome (WABS), caused by bi‐allelic variants in the DDX11 gene, is a rare cohesinopathy characterized by pre‐ and postnatal growth retardation, microcephaly, intellectual disability, facial dysmorphia, and sensorineural hearing loss due to cochlear hypoplasia. The DDX11 gene codes for an iron–sulfur DNA helicase in the Superfamily 2 helicases and plays an important role in genomic stability and maintenance. Fourteen individuals with WABS have been previously reported in the medical literature. Affected individuals have been of various ethnic backgrounds with different pathogenic variants. We report two unrelated individuals of Ashkenazi Jewish descent affected with WABS, who are homozygous for the c.1763‐1G>C variant in the DDX11 gene. Their phenotype is consistent with previously reported individuals. RNA studies showed that this variant causes an alternative splice acceptor site leading to a frameshift in the open reading frame. Carrier screening of the c.1763‐1G>C variant in the Jewish population revealed a high carrier frequency of 1 in 68 in the Ashkenazi Jewish population. Due to the high carrier frequency and the low number of affected individuals, we hypothesize a high rate of miscarriage of homozygous fetuses and/or subfertility for carrier couples. If the carrier frequency is reproducible in additional Ashkenazi Jewish populations, we suggest including DDX11 to Ashkenazi Jewish carrier screening panels. 相似文献
45.
D. J. Anderson L. Olaison J. R. McDonald J. M. Miro B. Hoen C. Selton-Suty T. Doco-Lecompte E. Abrutyn G. Habib S. Eykyn P. A. Pappas V. G. Fowler D. J. Sexton M. Almela G. R. Corey C. H. Cabell 《European journal of clinical microbiology & infectious diseases》2005,24(10):665-670
Enterococcal prosthetic valve infective endocarditis (PVE) is an incompletely understood disease. In the present study, patients
with enterococcal PVE were compared to patients with enterococcal native valve endocarditis (NVE) and other types of PVE to
determine differences in basic clinical characteristics and outcomes using a large multicenter, international database of
patients with definite endocarditis. Forty-five of 159 (29%) cases of definite enterococcal endocarditis were PVE. Patients
with enterococcal PVE were demographically similar to patients with enterococcal NVE but had more intracardiac abscesses (20%
vs. 6%; p=0.009), fewer valve vegetations (51% vs. 79%; p<0.001), and fewer cases of new valvular regurgitation (12% vs. 45%; p=0.01). Patients with either enterococcal PVE or NVE were elderly (median age, 73 vs. 69; p=0.06). Rates of in-hospital mortality, surgical intervention, heart failure, peripheral embolization, and stroke were similar
in both groups. Patients with enterococcal PVE were also demographically similar to patients with other types of PVE, but
mortality may be lower (14% vs. 26%; p=0.08). Notably, 93% of patients with enterococcal PVE came from European centers, as compared with only 79% of patients with
enterococcal NVE (p=0.03). Thus, patients with enterococcal PVE have higher rates of myocardial abscess formation and lower rates of new regurgitation
compared to patients with enterococcal NVE, but there are no differences between the groups with regard to surgical or mortality
rates. In contrast, though patients with enterococcal PVE and patients with other types of PVE share similar characteristics,
mortality is higher in the latter group. Importantly, the prevalence of enterococcal PVE was higher in the European centers
in this study. 相似文献
46.
F C Sotsiou P N Singhellakis A D Nikou A D Pappas C Vambouka N G Sklivagou D G Ikkos 《The Journal of pathology》1987,151(4):271-278
Recent evidence suggests that cimetidine given pre-operatively in primary hyperparathyroidism (1 degree HPT) might cause structural changes in parathyroid glands, while its suppressive effects on the disease are disputable. To determine these possible changes we studied 38 patients with 1 degree HPT who underwent parathyroidectomy. In 14 of these (group I) cimetidine was given pre-operatively (1000 mg orally daily for 4 weeks). The remaining 24 patients (group II) did not take any drug. Parathyroid function was estimated by nephrogenous cAMP (NcAMP) and serum immunoreactive parathyroid hormone (iPTH) measurements. Histological examination of the parathyroids was made by conventional techniques. In group I at the end of cimetidine treatment, the only change observed was a small but significant (p less than 0.05) decrease of plasma calcium (-0.77 mg/dl). Histologically, the glands of group I--compared with those of group II--showed the following findings: increased gland mass: mean increase 1050 mg (adenomas) and 700 mg (hyperplasias); central oedema in all the cases of group I only; increased (about 50 per cent) cellular size and intranuclear 'inclusions' in 10 out of 14 cases of group I only. It is concluded that treatment with cimetidine in 1 degree HPT is followed by histopathologic alterations leading to increased size of the diseased parathyroids. 相似文献
47.
Status of current clinical tests for human immunodeficiency virus (HIV): applications and limitations 总被引:1,自引:0,他引:1
Two laboratory tests are currently used to detect the human immunodeficiency virus (HIV) specific antibodies that are produced when an individual has been infected by the virus at some time. These include the enzyme-linked immunosorbent assay (ELISA) as the screening test and the Western blot (WB) as the confirmatory test. They are not yet optimally effective and have brought with them some problems, especially when used to screen low risk populations such as asymptomatic blood donors. Currently licensed ELISA tests used to detect HIV have sensitivities that range between 93 percent and 99 percent, and all have specificities greater than 99 percent. An important concern is that the positive predictive value for the ELISA screening test is low in spite of the fairly high sensitivity and high specificity values. This poor predictive value is due to the low prevalence of individuals in the general population who have been infected with HIV. Multiple causes of false positive ELISA and Western blot tests have been identified. They can be eliminated by utilizing reagent antigens which are produced by recombinant deoxyribonucleic acid (DNA). The false negative ELISA and Western blot tests can be reduced by tests designed to detect IgM antibodies to HIV. 相似文献
48.
There has been a recent notable increase in the number of patients in the United States seropositive for the human immunodeficiency virus (HIV) and also an increase in the number of otherwise healthy homosexuals with persistent generalized lymphadenopathy (PGL). Lymphoid tissue appears to be a favorite target for the initial viral infection, subsequent opportunistic infections, and associated neoplasms. Therefore, evaluation of PGL is important in understanding the nature of the disease. Biopsies of the acquired immunodeficiency syndrome (AIDS) lymph nodes show a spectrum of abnormal lymphoid proliferations, eventual lymphoid depletion, Kaposi's sarcoma, and malignant lymphoma. Although the individual features of AIDS-related lymphadenopathy may not be specific, the constellation of histologic, immunologic, ultrastructural, and fine needle aspiration findings is characteristic. 相似文献
49.
Summary Ca2+-ATPase activity has been shown to be associated with the nerve terminal plasma membrane at the frog neuromuscular junction. Using a modification of the Wachstein-Meisel procedure for localization of phosphatases, a dense reaction product forms at the neuronal plasma membrane/Schwann cell interface. It has been determined that this reaction product is associated with the plasma membrane of the nerve terminal and not the plasma membrane of the Schwann cell. No ATPase activity is demonstrated at the presynaptic portion of the plasma membrane facing the synaptic gap. When a preparation is denervated, a Schwann cell process moves into the space previously occupied by the nerve. There is no ATPase activity associated with the Schwann cell plasma membrane. Conversely, when the Schwann cell is selectively injured, dense reaction product continues to be associated with the nerve terminal plasma membrane. There is some indication that this ATPase activity is dependent on the presence of Ca2+ and Mg2+. Incubation in the calmodulin inhibitor, R24571, shows little inhibition of labelling. 相似文献
50.
Wide dynamic dose range of VIPAR polymer gel dosimetry 总被引:4,自引:0,他引:4
Kipouros P Pappas E Baras P Hatzipanayoti D Karaiskos P Sakelliou L Sandilos P Seimenis I 《Physics in medicine and biology》2001,46(8):2143-2159
In this work the extent of the linear dose response and the dynamic dose range of N-vinylpyrrolidone-argon based (VIPAR) polymer gels were investigated. VIPAR gels were irradiated using a 6 MV linear accelerator up to 60 Gy and a Nucletron microSelectron 192Ir HDR brachytherapy source to much higher doses to cover a dose range of two orders of magnitude. They were then MR scanned at 1.5 T to obtain T2-maps. VIPAR gel measurements obtained from the two irradiation regimes were calibrated against ion chamber measurements and dose calculations derived using the AAPM TG-43 protocol respectively. A satisfying agreement between the calibration results derived using the 6 MV x-rays and the 192Ir source was found for doses up to 60 Gy, implying that the response of the VIPAR gels is independent of photon energy and dose rate. A linear R2 dose response up to approximately 40 Gy and a dynamic dose range up to at least approximately 250 Gy were observed. VIPAR gel dose measurements derived using the monoexponentially fitted brachytherapy calibration data were found to be quite accurate. 相似文献