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排序方式: 共有1022条查询结果,搜索用时 15 毫秒
1.
Leonidas JC; Berdon WE; Valderrama E; Neveling U; Schuval S; Weiss SJ; Hilfer C; Godine L 《Radiology》1996,198(2):377
2.
Joint influence of fat and lean body composition compartments on femoral bone mineral density in premenopausal women. 总被引:8,自引:0,他引:8
M F Sowers A Kshirsagar M M Crutchfield S Updike 《American journal of epidemiology》1992,136(3):257-265
Body composition (fat and lean compartments) and bone mineral density were measured in 246 healthy premenopausal women, aged 20-40 years, residing in Tecumseh, Michigan. Body composition was measured using four-point bioelectrical impedance and values for fat and lean compartments categorized into tertiles. Additionally, each woman was classified into one of nine different cells based on her location within a 3 x 3 table which reflects the joint distribution of both fat and lean compartments. Bone mineral density of the proximal femur, including the femoral neck and trochanter, was measured using dual photon densitometry. The mean femoral neck bone mineral density values increased significantly and linearly for each tertile of muscle mass (0.90, 0.95, and 1.02 g/cm2, p less than 0.0002). Femoral bone mineral density increased significantly but not linearly as the fat compartment progressed from the lowest to the highest tertile (0.95, 0.93, and 0.99 g/cm2). Bone mineral density of the proximal femur was similar and significantly greater in the high muscle/low fat and high muscle/high fat body composition subgroups compared with bone mineral density in the seven other groups. However, women in the high muscle/low fat subgroup had substantially lower mean weight (67 vs. 91 kg, p less than 0.0001) and mean Quetelet index (22.1 vs. 33.7 kg/m2, p less than 0.0001) than women in the high muscle/high fat subgroup. Bone mineral density values were similar and significantly lower in the following body composition cells: low muscle/low fat, low muscle/medium fat, and low muscle/high fat. Similar findings were observed at the trochanteric site. Low muscle is a risk factor for low bone mineral density in young adult women while higher fat is protective only when associated with substantial muscle. 相似文献
3.
Hepatitis A virus (HAV) is distinguished from other picornaviruses by its tropism for the liver in infected hosts, a nonlytic infection in hepatocytes, and a slow and nonlytic growth cycle in cultured cells. Although the genome structure and organization of HAV appear to be similar to those of the other picornaviruses, the viral proteins synthesized in infected cells have not been previously characterized. We have utilized specific antisera raised in rabbits to recombinant HAV proteins expressed in Escherichia coli in an effort to identify both structural and nonstructural proteins in BS-C-1 cells throughout the course of a viral replication cycle. Replication was monitored by dot blot hybridization of viral genomes. Structural proteins VP0, VP1, VP2, and VP3 were found to accumulate during the infection cycle as did viral RNA. Nonstructural proteins 2C and 3D were not detected on immunoblots, although a minor amount of 2C could be detected by immunoprecipitation of lysates of radiolabeled, infected cells. The relative sensitivities of the various antisera were determined, and the failure to observe nonstructural proteins was shown not to be due to decreased sensitivity of the detection reagents. Thus, it appears that HAV nonstructural proteins do not accumulate in infected cells to levels comparable to those of capsid proteins. 相似文献
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Kaufmann SJ; Sharif K; Sharma V; McVerry BA 《Human reproduction (Oxford, England)》1998,13(2):498-499
The patient was diagnosed in childhood as having severe congenital
neutropenia and had recurrent admissions with severe infections. In 1987,
prior to getting married, she was sterilized. She continued to require i.v.
antibiotics when she contracted a severe infection. On one occasion, she
was treated with growth colony stimulating factor (G- CSF). Her increased
neutrophil count was sustained following this treatment. In June 1993, she
wished to start a family and underwent in- vitro fertilization (IVF)
treatment. G-CSF was given prior to oocyte retrieval. She conceived on her
first cycle and an ultrasound scan revealed a singleton pregnancy.
Throughout the course of the pregnancy, her white cell count was monitored
closely and remained at <1.0x10(9)/l. The pregnancy progressed
uneventfully and at 37 weeks gestation she was admitted for G-CSF
injections. At 38 weeks she was delivered of a boy weighing 3350 g, by
elective Caesarean section. His white cell count was normal. This is the
first case of G-CSF being used before conception and during pregnancy in a
patient with congenital neutropenia. It shows that advances in cytokine
therapy and close interdisciplinary liaison can lead to a successful
outcome and help patients, who would otherwise remain childless, to achieve
a family.
相似文献
7.
Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
The aim of the study was to determine whether a prior diagnostic testicle
biopsy can predict success or failure of testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI) in patients with
non-obstructive azoospermia caused by testicular failure, and what is the
minimum threshold of sperm production in the testis which must be surpassed
for spermatozoa to reach the ejaculate. Forty- five patients with
non-obstructive azoospermia caused by testicular failure underwent
diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure.
The diagnostic testicle biopsy was analysed quantitatively, and correlated
with the quantitative findings of spermatogenesis in patients with normal
spermatogenesis, as well as with the results of subsequent attempts at
TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure
had a mean of 0-6 mature spermatids/seminiferous tubule seen on a
diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in
men with normal spermatogenesis and obstructive azoospermia. These findings
were the same for all types of testicular failure whether Sertoli cell
only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia.
Twenty-two of 26 men with mature spermatids found in the prior testis
biopsy had successful retrieval of spermatozoa for ICSI, 12 of their
partners became pregnant, and are either ongoing or delivered. The study
suggests that 4-6 mature spermatids/tubule must be present in the testis
biopsy for any spermatozoa to reach the ejaculate. More than half of
azoospermic patients with germinal failure have minute foci of
spermatogenesis which are insufficient to produce spermatozoa in the
ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for
the presence of mature spermatids) can predict subsequent success or
failure with TESE-ICSI. Incomplete testicular failure may involve a sparse
multi-focal distribution of spermatogenesis throughout the entire testicle,
rather than a regional distribution. Therefore, it is possible that massive
testicular sampling from many different regions of the testes may not be
necessary for successful TESE-ICSI.
相似文献
8.
β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis. 相似文献
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