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排序方式: 共有730条查询结果,搜索用时 93 毫秒
151.
152.
Shibata E Hubel CA Powers RW von Versen-Hoeynck F Gammill H Rajakumar A Roberts JM 《Placenta》2008,29(10):879-882
Preeclampsia and intrauterine growth restriction (IUGR) are both associated with abnormal remodeling of maternal spiral arteries perfusing the placental site. This would be expected to be associated with reduced fetal growth, yet only one third of infants of mothers with preeclampsia are growth restricted. Infants with IUGR have decreased concentrations of amino acids in their blood and system A amino acid transporter activity is reduced in their placentas. Since infants of preeclamptic pregnancies have increased circulating amino acids, we tested system A amino acid transport activity of placental villous fragments from pregnancies with small for gestational age (SGA) infants with and without maternal preeclampsia and from uncomplicated and preeclamptic pregnancies with normal sized infants. We confirm the reduced uptake of amino acids in SGA pregnancies without preeclampsia but report that placental amino acid uptake of SGA infants with maternal preeclampsia is not reduced and is identical to uptake by normal and preeclamptic pregnancies with normal weight infants. 相似文献
153.
Vettriselvi V Vijayalakshmi K Paul SF Venkatachalam P 《The journal of obstetrics and gynaecology research》2008,34(3):301-306
AIM: To assess the association between polymorphisms in angiotensin converting enzyme and methylene tetrahydrofolate reductase genes and recurrent pregnancy loss by a case-control study in South Indian women. METHODS: DNA was extracted from peripheral blood leukocytes of 104 women with Recurrent Pregnancy Loss (RPL) and 120 controls. Genotyping of ACE Insertion Deletion and MTHFR C677T polymorphism were carried out by PCR and PCR-RFLP, respectively. RESULTS: No statistically significant difference was observed in the distribution of genotypes between cases and controls for ACE and MTHFR polymorphisms. Further, the combination of MTHFR and ACE genotypes failed to reveal an association. CONCLUSION: In conclusion, the present study reveals lack of association of MTHFR C677T and ACE I/D polymorphisms in RPL in South Indian women. However, we cannot exclude the possibility that other polymorphisms of ACE and MTHFR genes could be associated with the disease and might be clinically useful as a marker to assess risk for RPL. 相似文献
154.
Vivek Perumal Mario Scholze Niels Hammer Stephanie Woodley Helen Nicholson 《Clinical anatomy (New York, N.Y.)》2020,33(5):705-713
The ligament of the head of femur (LHF) or ligamentum teres has been reported to tense during hip adduction and also to provide mechanical stability to the joint. LHF injury is more common in females and also in right hip joints compared with left ones. Although this could be due to leg dominance, pelvic size or muscle strength, there is no study that has looked into these differences. This cadaveric biomechanical study aimed to compare potential differences in the mechanical behavior of the LHF between neutral and 20° adducted hip joints, sex, and sides. Tensile tests of the LHF were performed on 25 hip joints (mean age at death of 85.7 ± 7.5 years; 9 females, 4 males; 13 left, 12 right), positioned either neutrally or in adduction. The maximum force required to rupture the ligament, its strain at failure, tensile strength, linear stiffness, and elastic modulus were obtained and statistically compared between analysis groups. The maximum force the LHF could withstand before rupture averaged 57 ± 37 N, strain at failure of 59 ± 33%, tensile strength of 2.9 ± 1.8 MPa, linear stiffness of 5.4 ± 3.5 N/mm, and elastic modulus of 7.2 ± 3.8 MPa. The LHF length at failure was significantly greater in males compared with females (P = 0.02). Irrespective of joint position, there were no statistical differences in the stress–strain properties of the LHF between females and males, or sides. There may be other anatomical, functional, and demographic factors that could render the ligament tissue vulnerable to injury in these groups. Clin. Anat., 33:705–713, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
155.
156.
The aim of this study was to determine the possible usefulness of prolactin as a tumour marker in cancer of the cervix. Serum prolactin levels were measured using an enzyme linked immunosorbent assay in 105 women divided into malignant, pre-malignant and control groups. Elevated levels of prolactin were found in 42.9% of patients with malignant disease, 22.9% of controls and 14.2% of individuals with premalignant disease. The differences were not statistically significant. Although prolactin levels were found to be elevated in some patients with malignant disease of the cervix, further studies are needed to establish whether this is of clinical significance. 相似文献
157.
The uptake of norepinephrine into cortical punches from the brain of the rat was studied in the presence of buffer and plasma from patients containing bupropion and its metabolites. Even though bupropion and its metabolite (compound II) were equipotent in inhibiting the uptake of NE in buffer, compound II was twice as active as bupropion in the presence of human plasma. When the inhibition of uptake of NE in the presence of plasma, obtained from patients on bupropion on steady-state, was correlated with levels of bupropion and its metabolites (II, III, IV) a highly significant correlation was seen in the presence of compound II. Since this compound accumulated in plasma from patients 20-100 times that of the parent compound, the mode of action of bupropion may in part be due to the effect of this compound on the uptake of NE. 相似文献
158.
159.
In vivo activity of amikacin alone or in combination with clofazimine or rifabutin or both against acute experimental Mycobacterium avium complex infections in beige mice. 总被引:14,自引:13,他引:1
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P R Gangadharam V K Perumal N R Podapati L Kesavalu M D Iseman 《Antimicrobial agents and chemotherapy》1988,32(9):1400-1403
The in vivo activity of amikacin, used alone or in combination with rifabutin or clofazimine or both, was assessed in the treatment of early and established Mycobacterium avium complex infections in beige mice. Amikacin given alone at a dose of 50 mg/kg, in one, two, or three divided doses, showed remarkable activity. Addition of clofazimine increased the activity significantly, but addition of the third drug, rifabutin, did not further improve the results. Amikacin-containing regimens are worthy of consideration for investigations in patients with M. avium complex infections. 相似文献
160.
N Selvakumar S Sivagamasundari E Prabhakaran R Govindaraju M Perumal R Granich F Wares L S Chauhan P R Narayanan 《The international journal of tuberculosis and lung disease》2005,9(2):223-225
To evaluate the suitability for panel testing of heat-fixed unstained sputum AFB smears stored for up to 10 months, panels of slides were prepared at the national laboratory and stored under ambient conditions. Every month, three slides were utilised for panel testing in each of 12 microscopy centres; 70 smears were checked in a blinded fashion after 10 months. Reading errors occurred in 15/360 slides used in panel testing and in 4/70 slides used in blinded checking. The quality and grading of heat-fixed unstained smears were unaffected for up to 10 months and were found suitable for panel testing. 相似文献