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71.
The use of an episiotomy for vaginal delivery is a controversial topic in modern obstetrics. If one is done, however, correct technique of perineal trauma repair is important. The usual episiotomy has traditionally been closed with interrupted suture. The use of a less reactive material, e.g. polyglycolic acid (Dexon), seem to be suitable for subcutaneous skin closure and beneficial in terms of acute postpartum discomfort and healing. The comparison of healing and patient comfort parameters between interrupted and subcutis polyglycolic acid suture used for episiotomy repair after delivery was done. Patients had follow-up during hospital stay, and two months after delivery a self administered questionnaire was sent to all women who participated, enquiring about perineal pain, resumption of sexual intercourse and cosmetics of suture line. Of 52 patients who had repair with interrupted suture, 21 were lost to follow-up. Of 65 gravidas who had repair with subcutis suture, 23 were lost to follow-up. At the 3rd day postpartum examination, patients with subcutis sutures had significantly better healing. An inflammatory process was present in 2 of 52 patients with interrupted sutures comparable with 1 of 65 in the subcutis group, and a gaping wound in 0 of 52 and 1 of 65, respectively. Recovery of function, measured by resumption of sexual activity by 8 weeks, was demonstrated in 5 of 31 patients with interrupted sutures versus 24 of 42 patients who had subcutis sutures. Episiotomy repair with subcutis polyglycolic acid (Dexon) offers significant advantages over traditional interrupted suture, both in terms of wound healing and resumption of sexual activity.  相似文献   
72.
Fatty masses, especially solid lipomas, in the paediatric abdomen are very rare. We present such a case, that of an 11-year-old boy who was admitted with abdominal pain and distension. The pre-operative diagnosis of lipoma was suggested by US and CT. The diagnosis of simple lipoma arising in the leaves of the small bowel mesentery, without immature cells, was verified microscopically after the operation. The tumour was enucleated from the mesenterium leaving the intestine intact. We underline the importance of US and CT as pre-operative diagnostic tools.  相似文献   
73.
Paclitaxel induces a cell cycle block at G2-M phase by preventing the depolymerization of microtubules and induces p53-independent apoptosis in many cancer cells. We observed that gastric cancer cells treated with paclitaxel have shown a cyclin-dependent kinase (CDK)4 down-regulation. This paclitaxel-induced CDK4 down-regulation resulted in a cell cycle arrest at G1-S phase. To confirm this observation, we prepared stable transfectants that overexpressed CDK4 and analyzed the cell cycle progression. Ectopic expression of CDK4 in SNU cells resulted in a release of paclitaxel-induced G1 arrest. The release of G1 arrest by enforced expression of CDK4 seems to make the cells more sensitive to paclitaxel-induced apoptosis. From this finding, we could then suggest that paclitaxel treatment induces both G1-S and G2-M blocks in the cell cycle progression of gastric cancer cells.  相似文献   
74.
AIMS: To observe the vascular pattern of the peripapillary circle of Zinn-Haller in humans by fundus fluorescein angiography. METHODS: 307 cases (from 212 patients) of fundus fluorescein angiograms performed in patients with myopic degeneration were evaluated to find the circle of Zinn-Haller and to observe its fundus fluorescein angiographic features. RESULTS: 15 cases (from 13 patients) with the circle of Zinn-Haller were found. It appeared as concentric or zigzag-shaped vascular fillings within the temporal crescent region. All cases were observed in pathological myopia with peripapillary atrophy and a tilted disc. Each arterial circle showed variations in location and shape. CONCLUSIONS: The temporal part of the circle of Zinn-Haller can be revealed by fundus fluorescein angiography particularly in pathological eyes with prominent peripapillary atrophy and a tilted disc. The morphological variation of this arterial circle should be considered.  相似文献   
75.
Nanostructured diamond films were grown to a thickness of approximately 35 µm by a 30 kW, 915 MHz, microwave plasma-assisted chemical vapor deposition (MPCVD) on chemically treated WC–6 wt.% Co tool inserts. Rockwell indentation tests were performed to evaluate the adhesion of the films and compared to that of traditional microcrystalline diamond. A series of high speed dry turning tests on high-silicon (18 wt.% Si) aluminum alloy A390 under continuous and interrupted modes were performed and comparisons were carried out to investigate the wear behavior on tool inserts that were uncoated, coated with nanostructured diamond, and commercial PCD (polycrystalline diamond cutter) ones. The tests showed that nanostructured diamond coatings demonstrated excellent durability against the highly abrasive A390 aluminum–silicon alloys in high speed dry turning. Ultra fine grain structure of this coating produces workpiece surface finish comparable or even better than PCD tools in the range we studied. Excellent coating adhesion of nanostructured diamond on WC–6% Co substrates leads to reliable wear behavior. For the first time, we evaluated the performance of nanostructured diamond film coated insert under high speed interrupted turning mode. A “self-cleaning” mechanism was observed which can significantly improve the performance of nanostructured diamond films. Micro-Raman spectra were taken on tested tools to study the wear mechanism of the coating.  相似文献   
76.
A material of flies collected in two localities (altitude of 3900 and 4500 m) in the Barun Khola Valley (East Nepal) was studied, representing the early spring aspect of the species composition of flies. Of the total number of 2309 fly specimens 99.3% represented two species of the genus Paregle (P. aterrima, P. sp.); both are autochthonous high altitude hemisynanthrophic forms. The remainining 0.7% represent 9 species, most of which are more or less eurytopic species of palearctic or holoarctic distribution (Calliphora vicina, C. vomitoria, Meoneura flavifacies, Scatophaga stercoraria, Hydrotea hirticeps, Orthellia caesarian, Paregle danieli, Anthomyiidae g. sp. 1, g. sp. 2).  相似文献   
77.
Coagulase-negative staphylococcus (C-NS) are regarded as normal flora of the lids and conjunctiva. The ability of these organisms to cause conjunctivitis and blepharitis can be overlooked or disregarded. To elucidate the role of individual C-NS species in these eye diseases we compared Staphylococcus sp. isolated from the conjunctiva and lids of 50 healthy volunteers with 248 strains of Staphylococcus isolated from patients with staphylococcal conjunctivitis or blepharitis. S. epidermidis was the most frequent species isolated from the conjunctiva and lids of both groups. S. aureus was isolated only from infected patients. No individual C-NS species was found to be significantly associated with eye disease, but the colony count of C-NS after isolation was a useful indicator of conjunctivitis and blepharitis. The ability of Staphylococcus to ferment mannitol or mannose was associated with isolates only from infected patients.  相似文献   
78.
79.
The selection of NIH 3T3 cells expressing a hydroxytamoxifen-inducible c-Raf-1-estrogen receptor fusion protein (c-Raf-1-BxB-ER) in the absence or presence of the inducer results in dramatic differences in the expression levels of the fusion protein. Hydroxytamoxifen-mediated constitutive activation of the Raf signal favors the selection of cells expressing low levels of c-Raf-1-BxB-ER. Cells selected in the absence of hydroxytamoxifen express up to 20 times higher levels of the inducible Raf kinase. Activation of the oncogenic Raf kinase in cells expressing low levels leads to a weak activation of the Raf/Mek/Erk cascade and the induction of S phase in confluent cells. The activation of cells expressing high levels of the kinase leads to a strong persistent signal and inhibits DNA synthesis and mitosis in proliferating cells. The inhibition of DNA synthesis and cell division is presumably due to the elevated expression of the cyclin-dependent kinase inhibitor p21cip1, similar to cells exposed to ionizing radiation. Despite the inhibition of DNA synthesis and mitosis, the constitutive activity of the Raf signaling pathway is still able to initiate cell growth. Activation of the high-intensity Raf signal in arrested serum-starved cells induces cell growth up to a size corresponding to that of M-phase cells in the absence of DNA synthesis. High-intensity Raf signals in proliferating cells consistently lead to an accumulation of cells with the size of M-phase cells and the DNA content of G1 cells or G2-M-phase cells. Therefore, the activation of Raf kinase is sufficient to drive cell growth, even in the presence of high levels of the cyclin-dependent kinase inhibitor p21cip1.  相似文献   
80.
OBJECTIVE: Our goal was to determine the relationship between critical factors and conditions such as gestational age and exposure time to elevated glucose levels in diabetic embryopathy. STUDY DESIGN: A postimplantation rat embryo culture was used as a model for investigation. The effect of various factors on embryonic development was studied. Experiments were conducted with increasing glucose concentrations (150 to 905 mg/dl, n = 186), at various gestational ages (10 to 12 days, n = 169), and for varying durations of exposure (30 to 180 minutes, n = 169). Gross morphologic characteristics of the yolk sac and embryo were assessed. RESULTS: Embryopathy was induced by hyperglycemia in a dose-related fashion: a 20% rate at two times control glucose concentration, almost a 50% rate at four times control, and approximately a 100% abnormality rate at more than six times control. A critical window in gestational age, days 10 to 11, and a minimum exposure time to hyperglycemia of 2 hours were necessary to induce teratogenesis. CONCLUSIONS: Diabetic teratogenesis occurs in a dose-related fashion and requires a minimum exposure time and critical gestational age. Only synchronization of these critical conditions induces embryonic maldevelopment. Furthermore, nonsynchronized aberrant conditions may result in apparently normal embryonic development.  相似文献   
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