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61.
62.
Soubhagya R. Nayak Ashwin Krishnamurthy SJ Madhan Kumar Latha V. Prabhu Bhagath Kumar Potu Sujatha D’Costa Anu Vinod Ranade 《Hand (New York, N.Y.)》2010,5(1):31-36
The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA)
can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar
artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation
of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal
tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation
of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed
to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed
with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the
RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm.
The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered
as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found
in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will
add to the existing knowledge of the vascular anatomy of forearm and hand. 相似文献
63.
Summary The purpose of this study was to evaluate the occurrence of superficial flaws after machining and to identify fracture initiation and propagation in three‐unit heat‐treated machined fixed partial dentures (FPDs) substructures made of hot isostatic pressed (HIPed) yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) after loaded to fracture. Four three‐unit HIPed Y‐TZP‐based FPDs substructures were examined. To evaluate the occurrence of superficial flaws after machining, the surfaces were studied utilizing a fluorescent penetrant method. After static loading to fracture, characteristic fracture features on both mating halves of the fractured specimens were studied using a stereomicroscope and a scanning electron microscope. Grinding grooves were clearly visible on the surfaces of the machined FPDs substructures, but no other flaws could be seen with the fluorescent penetrant method. After loading to fracture, the characteristic fracture features of arrest lines, compression curl, fracture mirror, fracture origin, hackle and twist hackle were detected. These findings indicated that the decisive fracture was initiated at the gingival embrasure of the pontic in association with a grinding groove. Thus, in three‐unit heat‐treated machined HIPed Y‐TZP FPDs substructures, with the shape studied in this study, the gingival embrasure of the pontic seems to be a weak area providing a location for tensile stresses when they are occlusally loaded. In this area, fracture initiation may be located to a grinding groove. 相似文献
64.
S Gagnon W Fraser B Fouquette A Bastide M Bureau J Y Fontaine C Huot 《Prenatal diagnosis》1992,12(1):9-18
During a 7-year period, 117 fetal karyotypes were available from 131 genetic amniocenteses. These procedures were performed between 14 and 37 weeks' gestation for the following abnormal ultrasound findings: (1) intrauterine growth retardation (IUGR)--61 cases; (2) fetal malformation--71 cases; and (3) amniotic fluid volume (AFV) abnormality--60 cases. Chromosomal abnormalities were identified in 19 cases (16.2 per cent). Aneuploidy was 2.5 times as frequent in the presence of malformations than in their absence. No correlation was demonstrated between specific fetal malformations and specific chromosomal abnormalities. Aneuploidy was also twice as frequent in the presence of symmetrical IUGR than in its absence. No chromosomal abnormalities were found among eight cases of asymmetrical IUGR. Four cases of aneuploidy presented with isolated IUGR, three of these involving the X chromosome. The frequency of aneuploidy was the same with or without abnormalities of AFV (14.3 versus 16.4 per cent). No chromosomal abnormality was found associated with isolated AFV abnormalities. 相似文献
65.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
66.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics. 相似文献
67.
68.
Activation of cyclin D1-kinase in murine fibroblasts lacking both p21(Cip1) and p27(Kip1) 总被引:6,自引:0,他引:6
Sugimoto M Martin N Wilks DP Tamai K Huot TJ Pantoja C Okumura K Serrano M Hara E 《Oncogene》2002,21(53):8067-8074
Deregulation of D-type cyclin-dependent kinases (CDK4 and 6) is widely observed in various human cancers, illustrating their importance in cell cycle control. Like other cyclin-dependent kinases (CDKs), assembly with cyclins is the most critical step for activation of CDK4/6. As previously reported elsewhere, we observed that the level of cyclinD1-CDK4 complex and its associated kinase activity were significantly low in asynchronously proliferating mouse embryo fibroblasts lacking both p21(Cip1) and p27(Kip1) (p21/p27-null MEFs). These evidences imply that p21(Cip1) and p27(Kip1) CDK inhibitors are 'essential activators' of cyclin D-kinases. We, however, discovered here that both the assembly and activation of cyclin D1-CDK4 complex occur when quiescent p21/p27-null MEFs were stimulated to re-enter the cell cycle. This mitogen-induced cyclin D1-kinase activity was blocked by overexpression of p16(INK4a) and resulted in the inhibition of S phase entry in p21/p27-null MEFs. Furthermore, ectopic expression of p34(SEI-1), a mitogen-induced CDK4 binding protein, increased the levels of active cyclinD1-CDK4 complex in asynchronously proliferating p21/p27-null MEFs. Together, our results suggest that there are several independent ways to stimulate the assembly of cyclin D1-CDK4 kinases. Although p21(Cip1) and p27(Kip1) play a role in this process, our results demonstrate that additional mechanisms must occur in G0 to S phase transition. 相似文献
69.
Putong NM Pitisuttithum P Supanaranond W Phonrat B Tansuphasawadikul S Silachamroon U Yuda HC Bussaratid V Aswapokee N 《The Southeast Asian journal of tropical medicine and public health》2002,33(2):346-351
A one year retrospective study, was conducted at Bamrasnaradura Hospital, Nonthaburi Province, Bangkok, Thailand, of 271 subjects with both TB and HIV/AIDS. Single males (median age group 31 to 40 years) were most likely to develop co-infection. The commonest clinical manifestations on initial presentation included a low grade fever, cough, weight loss, lymphadenopathy with pancytopenia, and lung infiltrates. Multi-drug resistant TB (MDR-TB) was found in 26.6% of the subjects which was significantly associated with a past history of anti-TB treatment (p = 0.005; OR=2.5); it was also significantly associated with disseminated TB (p = 0.022; OR=1.9) and mortality (p= 0.013; OR=2.8). Analysis of clinical outcomes showed that 46.7% were lost to follow-up and 13.3% had died by the time of follow-up. Among those who survived, only 11.4% had been successfully treated; the rest had not improved due to relapse (2.9%), therapeutic failure (8.8%), treatment in progress (5.9%), and failure to complete treatment (10.7%). 相似文献
70.
SJ KANG HD WOO JY CHOI YJ LEE HW CHUNG 《中国药理学与毒理学杂志》2006,20(3):224-247
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins. 相似文献