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11.
12.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
13.
14.
Meniscal abnormalities: prospective correlation of double-contrast arthrography and arthroscopy 总被引:2,自引:0,他引:2
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed. 相似文献
15.
16.
Aromatization of androgens is important for skeletal maintenance of aged male rats 总被引:16,自引:0,他引:16
D. Vanderschueren E. Van Herck R. De Coster R. Bouillon 《Calcified tissue international》1996,59(3):179-183
A nonsteroidal aromatase inhibitor vorozole (VOR) was administered to aged (12 months old) male Wistar rats and its effect
was compared with the effect of androgen deficiency. The rats were either sham-operated (SHAM) or orchidectomized (ORCH) and
treated with or without VOR. Thus, four experimental groups were created (SHAM, ORCH, SHAM + VOR, ORCH + VOR). The follow-up
period was 4 months. At the end of the experimental period, bone mineral density (BMD) of the first four lumbar vertebrae
and right femur was measured ex vivo with dual-energy X-ray absorptiometry, bone formation was evaluated by serum osteocalcin, and bone resorption by urinary excretion
of (deoxy)pyridinoline. Orchidectomy increased bone resorption 2- to 3-fold whereas bone formation was only slightly increased.
Treatment of intact male rats with VOR also increased bone resorption (+30% increase) whereas bone formation was not increased
in this SHAM + VOR group. Their BMD was 7% lower in the femur (P < 0.01) and 6% lower in the lumbar vertebrae (P < 0.01) compared with the SHAM group that had not received VOR. Moreover, this decrease of bone mineral density was not significantly
different from the expected decrease of bone density observed in the ORCH groups (6–10%). This was also reflected by a decrease
of calcium content of the first four lumbar vertebrae of 15% (P < 0.001) in the SHAM + VOR group and 9–14% (P < 0.05) in the ORCH groups compared with the SHAM group, respectively. These data therefore suggest that inhibition of aromatization
of androgens into estrogens increases bone resorption and bone loss similar to that observed after complete removal of androgens.
Aromatization of androgens into estrogens may therefore, at least partly, explain the effects of androgens on skeletal maintenance.
Received: 13 October 1995 / Accepted: 23 February 1996 相似文献
17.
18.
The development of both adenocarcinoma of the jejunum and in situ squamous carcinoma of the oesophagus in an adult coeliac patient is described. Good evidence that adenocarcinoma of jejunum occurs more frequently in patients with coeliac disease has recently become available though this association has been suggested for some time. While oesophageal carcinoma has long been associated with coeliac disease, in situ carcinoma of oesophagus has not been previously described in these circumstances. We feel that the risk of this complication, as calculated from published series, warrants a screening programme for oesophageal malignancy in adult coeliacs. 相似文献
19.
20.
A 50-kDa membrane protein mediates sialic acid-independent binding and infection of conjunctival cells by adenovirus type 37 总被引:6,自引:0,他引:6
The ocular tropism of adenovirus type 37 (Ad37) does not correlate with the wide distribution of the 46-kDa coxsackievirus and adenovirus receptor (CAR), the major receptor for most adenovirus serotypes. We previously found that Ad37 infects and binds well to conjunctival cells (Chang C), but poorly to lung epithelial (A549) cells that express CAR and hypothesized that this serotype uses a distinct receptor that is selectively expressed on conjunctival cells. To test this, we produced particles of a fiber-deleted Ad5 vector containing the Ad37 fiber protein. The "pseudotyped" vector infected Chang C cells better than A549 cells using a CAR-independent pathway. Ad37 binding was calcium-dependent and was abolished by protease digestion of cell surface proteins. Using a virus overlay protein blot assay (VOPBA), we detected calcium-dependent Ad37 binding to 50- and 60-kDa membrane proteins on permissive Chang C cells. In contrast, calcium-dependent binding was detected with only the 60-kDa protein on nonpermissive A549 cells. Ad19p, a closely related serotype that failed to bind to conjunctival cells, recognized the 60-kDa, but not the 50-kDa, protein. Ad37 has been reported to use sialic acid instead of CAR as a cell receptor on A549 cells. Pretreatment of Chang C cells with neuraminidase abolished Ad37 binding to only the 60-kDa protein, suggesting that sialic acid mediates Ad37 binding to the 60-kDa protein. The pseudotyped Ad37 vector was also able to infect neuraminidase-treated Chang C cells. Thus, subgroup D adenoviral binding to the 50-kDa protein is calcium-dependent and cell type- and serotype-specific, whereas binding to the 60-kDa protein is not necessary for infection of conjunctival cells. Together, these data suggest that the 50-kDa protein is the major receptor for Ad37 on conjunctival cells. 相似文献