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排序方式: 共有973条查询结果,搜索用时 750 毫秒
921.
Silber SJ; Nagy Z; Devroey P; Camus M; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(12):2693-2700
Factors other than spermatozoa could be the major determinant of the
success of assisted reproduction treatment in cases of male infertility.
Our aim was to evaluate the effect of the wife's age and ovarian reserve on
assisted reproduction success rates in the most severe type of male
infertility, i.e. azoospermia. A total of 249 consecutive couples suffering
from male infertility caused by azoospermia underwent microsurgical
epididymal sperm aspiration (MESA) or testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI). Of these men, 186 had
irreparable obstructive azoospermia, and 63 had non-obstructive azoospermia
due to testicular failure. Neither the pathology, the source, the quantity,
nor the quality of spermatozoa had any effect on fertilization or pregnancy
rates. Maternal age and ovarian reserve (number of eggs) had no effect on
fertilization or embryo cleavage, but did dramatically affect the embryo
implantation, pregnancy and delivery rates. Wives of azoospermic men who
were in their 20s had a 46% live delivery rate per cycle, wives aged 30-36
years had a 34% live delivery rate per cycle, wives aged 37- 39 years had a
13% live delivery rate per cycle, and wives > or = 40 years had only a
4% live delivery rate per cycle. The number of eggs retrieved also affected
pregnancy and delivery rate, but to a lesser extent than age. In virtually
all cases of obstructive azoospermia, and in 62% of cases with
non-obstructive azoospermia caused by germinal failure, sufficient
spermatozoa could be retrieved to perform ICSI, with normal fertilization
and embryo cleavage. However, the pregnancy rate and the live delivery rate
were dependent strictly on the age of the wife, and on her ovarian reserve.
Unfortunately, exaggerated claims of high pregnancy rates can thus easily
be made by manipulating, in a very simple way, selection for female
factors.
相似文献
922.
SJ Duckett 《Australia and New Zealand Health Policy》2005,2(1):14
There are recognised shortages in most health professions in Australia. This is evidence that previous attempts at health workforce planning have failed. This paper argues that one reason for such failure is the lack of appropriate structures for health workforce planning. It also suggests that Australia needs to move beyond planning for particular professions and that health workforce planning needs to be based on identifying skill shortages as much as shortages in particular named professionals.The paper proposes specific policy suggestions to facilitate workforce flexibility and health workforce planning in Australia. 相似文献
923.
Glycoform composition of serum gonadotrophins through the normal menstrual cycle and in the post-menopausal state 总被引:7,自引:2,他引:7
Anobile CJ; Talbot JA; McCann SJ; Padmanabhan V; Robertson WR 《Molecular human reproduction》1998,4(7):631-639
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing
hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean
+/- SD) throughout their menstrual cycles and in five post- menopausal
women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7- 4) revealed
menstrual cycle stage- and postmenopausal-related differences in the serum
gonadotrophin charge. There were differences in the proportion of FSH with
an isoelectric point (pl) > 4.3 across phases of the menstrual cycle (P
= 0.019): midcycle (MC) 50%; early to mid-follicular (EMF) 36%; late
follicular (LF) 37%, luteal (L) 29% and following the menopause (PM) 17%.
There was no significant difference in the proportion of LH with pl >
6.55 between midcycle (53%) and EMF, LF or L phases (36, 43 and 32%
respectively); although all were greater than that found in the menopause
(13%). Concanavalin A chromatography revealed less (P < 0.005) complex
FSH and LH glycoforms at midcycle (63 and 13%) than in the EMF, LF and L
phases (90 and 18; 90 and 20 and 93 and 24% respectively). Menopausal
gonadotrophins were least complex (FSH 34%, LH 4%). There was a direct
relationship between serum FSH and FSH pl/complexity, and less acidic FSH
was associated with reduced FSH complexity. Increased oestradiol was
associated with basic FSH isoforms during the menstrual cycle and reduced
follicular phase FSH complexity. We conclude that changes in gonadotrophin
glycoforms occur through the menstrual cycle which are related to changes
in the prevailing steroid environment. Following the menopause oestrogenic
loss resulted in acidic, relatively simple glycoforms.
相似文献
924.
Effect of antiphospholipid antibodies in women undergoing in-vitro fertilization: role of heparin and aspirin 总被引:3,自引:4,他引:3
Kutteh WH; Yetman DL; Chantilis SJ; Crain J 《Human reproduction (Oxford, England)》1997,12(6):1171-1175
To describe the prevalence of antiphospholipid antibodies in women
undergoing in-vitro fertilization (IVF) and to determine if heparin and
aspirin affect implantation rates, 191 women with a history of infertility
undergoing IVF were prospectively tested for antiphospholipid antibodies.
This was a two-centre, non-randomized comparison of women with positive
antiphospholipid antibodies receiving heparin and aspirin versus standard
treatment. An enzyme-linked immunosorbent assay, with referenced standards
and known positive and negative sera on each plate, was utilized to measure
antibodies to cardiolipin, phosphatidylinositol, phosphatidylglycerol,
phosphatidylserine and phosphatidylethanolamine. Statistical analyses of
results included analysis of variance and Fisher's two-tailed exact test.
Antiphospholipid antibodies were detected in 18.8% of patients undergoing
IVF compared with only 5.5% in the 200 normal controls, 26% in 200 women
with recurrent pregnancy loss, and 32% in 200 women with systemic lupus
erythematosus. In conclusion, antiphospholipid antibodies were found more
frequently in women undergoing IVF than in the normal control population.
Although implantation rates appeared higher in the group of women treated
with heparin and aspirin, no statistically significant differences were
detected in implantation, pregnancy and ongoing pregnancy rates between
those who received standard therapy and those treated with heparin and
aspirin.
相似文献
925.
1 病例报告 患者女性 ,33岁 .上腹部不适 2 mo. 3mo前无明显诱因出现背部疲劳 .不伴有疼痛 ,无发热、咳嗽、盗汗 .尿常规 GL U( ) ,UBG(+ ) ,HCG正常 .血糖 GL U 8.1mmol· L- 1 . B超提示腹后实性包块 .手术所见 ,肝左叶巨大肿物 11cm× 9cm× 10 cm位于小网膜囊内与胰腺、胃小弯粘连 ,肝门被侵及 .大部分切除肿瘤 .临床诊断 :腹膜后肿物 .1.1 病理检查 肉眼观察 :暗红色灰褐色包块一个 V:10 cm× 8cm× 3.5 cm,无包膜 ,切面囊实相间 ,部分区域坏死 ,粘液物流出 ,质地软 ,鱼肉状 .1.2 显微镜观察 瘤细胞体积中等大小 ,胞质丰… 相似文献
926.
927.
KT Wilson KS Ramanujam HL Mobley RF Musselman SP James SJ Meltzer 《Gastroenterology》1996,111(6):1524-1533
BACKGROUND & AIMS: Helicobacter pylori uniquely colonizes the human stomach and produces gastric mucosal inflammation. High-output nitric oxide production by inducible nitric oxide synthase (iNOS) is associated with immune activation and tissue injury. Because mononuclear cells comprise a major part of the cellular inflammatory response to H. pylori infection, the ability of H. pylori to induce iNOS in macrophages was assessed. METHODS: H. pylori preparations were added to RAW 264.7 murine macrophages, and iNOS expression was assessed by Northern blot analysis, enzyme activity assay, and NO2- release. RESULTS: Both whole H. pylori and French press lysates induced concentration-dependent NO2- production, with peak levels 20-fold above control. These findings were paralleled by marked increases in iNOS messenger RNA and enzyme activity levels. iNOS expression was synergistically increased with interferon gamma, indicating that the H. pylori effect can be amplified by other macrophage-activating factors. Studies of lipopolysaccharide (LPS) content and polymyxin B inhibition of LPS suggested that the H. pylori effect was attributable to both LPS- dependent and -independent mechanisms. CONCLUSIONS: iNOS expression in macrophages is activated by highly stable H. pylori products and may play an important role in the pathogenesis of H. pylori-associated gastric mucosal disease. (Gastroenterology 1996 Dec;111(6):1524-33) 相似文献
928.
SCHLAPBACH P.; BEYELER CH.; GERBER N. J.; LINDEN SJ. VAN DER; BURGI U.; FUCHS W. A.; EHRENGRUBER H. 《Rheumatology (Oxford, England)》1992,31(8):531-534
The presence of clinically palpable finger joint nodules a(Heberden'sand Bouchard's nodes) was documented in 123 consecutive caseswith diffuse idiopathic skeletal hyperostosis (DISH) of thethoracic spine and 191 matched DISH negative controls. The prevalenceof palpable finger joint nodules was almost twice as frequentin cases with spinal DISH compared to controls (46% versus 31%,X2 = 7.67, P<0.01; multivariate adjusted odds ratio OR =1.84; 95% CI: 1.142.98). This increase was most markedat the proximal interphalangeal joint, in males and in patientsup to the age of 65 years. In addition and independent of othervariables such as hyperostotic features, age and sex, the prevalenceof palpable finger joint nodules was about twice as high inprobands with a history of physically heavy work compared tothose without (43% ver sus 26%, X = 9.18, P<0.005; multivariateadjusted odds ratio OR = 2.10; 95% CI: 1.263.52). Fromthese results we con clude that DISH should be considered asan independent risk factor in the development of finger jointnodules. KEY WORDS: Heberden's nodes, Diffuse idiopathic skeletal hyperostosis (DISH), Controlled study 相似文献
929.
Sieber F; Krueger GJ; O'Brien JM; Schober SL; Sensenbrenner LL; Sharkis SJ 《Blood》1989,73(1):345-350
The Friend virus complex was used as a model to study the effects of merocyanine 540 (MC 540)-mediated photosensitization on enveloped viruses. Simultaneous exposure to the lipophilic dye MC 540 and white light inactivated cell-free virus, cell-associated virus, and virus- transformed cells. When used under experimental conditions that are known to preserve most mature blood cells, at least some coagulation factors, and a significant portion of the pluripotent hematopoietic stem cell compartment, MC 540-mediated photosensitization reduced virus titers by greater than or equal to 4 log and the concentration of in vitro clonogenic erythroleukemia cells by greater than or equal to 5 log. Animals that received a single intravenous injection of photosensitized virus were resistant to a subsequent challenge with live virus. High sensitivity to MC 540-mediated photosensitization appears to be a property that is shared by other enveloped viruses. Thus, photosensitization mediated by MC 540 may be of benefit in the sterilization of blood products (in particular, cellular products), the production of vaccines, and selected areas of antiviral therapy. 相似文献
930.