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101.
The introduction of new modalities of treatment for the very premature infant and advanced life-support systems have led to a decrease in the neonatal mortality rate, and a consequent increase in the population of the tiniest survivors. Many premature infants that survive their neonatal intensive care unit stay have permanent injury to their vital organs including eyes, lungs, brain, and gastrointestinal tract, causing them to have lifelong disabilities. Whether these injuries are a result of their prematurity, or are caused by the life-support systems and treatments is a subject of much dispute. This article explains the process of iatrogenicity and separates the iatrogenic problems that are preventable from those that are currently unpreventable.  相似文献   
102.
Physiologic events in the last few weeks of pregnancy coupled with the onset of spontaneous labor are accompanied by changes in the hormonal milieu of the fetus and its mother, resulting in preparation of the fetus for neonatal transition. Rapid clearance of fetal lung fluid is a key part of these changes, and is mediated in large part by transepithelial sodium reabsorption through amiloride-sensitive sodium channels in the alveolar epithelial cells, with only a limited contribution from mechanical factors and Starling forces. This article discusses the respiratory morbidity associated with elective cesarean section, the physiologic mechanisms underlying fetal lung fluid absorption, and potential strategies for facilitating neonatal transition when infants are delivered by elective cesarean section before the onset of spontaneous labor.  相似文献   
103.
Galea P  Barigye O  Wee L  Jain V  Sullivan M  Fisk NM 《Placenta》2008,29(8):734-742
The renin-angiotensin system (RAS) in twin-twin transfusion syndrome (TTTS) is up-regulated in the donor fetus's kidneys, but down-regulated in the recipient's. Ultrasonographic and echocardiographic features suggest that the recipient is also exposed to RAS components. In this study we investigated the role and origin of RAS components in the recipient fetus. Monochorionic diamniotic (MCDA) pregnancies were recruited from a tertiary fetal medicine service. Cord blood was collected from MCDA twins (TTTS and control non-TTTS) at delivery for renin and angiotensin II immunoassays. Placental tissue was flash-frozen for mRNA and protein expression or formalin-fixed for immunohistochemistry. Archival placenta and kidney samples were used for immunohistochemistry and in-situ hybridization. Plasma renin levels were elevated (p<0.05) in recipients (median 201pg/ml, range 54-315pg/ml) and donors (125pg/ml, 25-296) with TTTS compared to controls (2.5pg/ml, 1.1-1.5pg/ml). The same was found with angiotensin II with high levels in both recipients (300.5pg/ml, 86.1-488pg/ml) and donors (239pg/ml, 76.6-422) compared to controls (169.5pg/ml, 89-220pg/ml, p<0.05). Renin mRNA expression, and protein appeared qualitatively higher in the placental territory of the recipient compared to that of the donor and non-TTTS controls. We conclude that both fetuses in TTTS are exposed to high levels of RAS components; these appear to be produced from different sites, namely the kidney of the donor, and the placenta of the recipient. Given the markedly different phenotypes in the genetically identical fetuses with TTTS, we suggest that the source of RAS components may influence their clinical manifestations.  相似文献   
104.
The aim of this investigation was to determine the metabolism of glyburide (GL) by microsomes prepared from placentas obtained from uncomplicated pregnancies (UP), women with gestational diabetics (GD) on a diabetic diet, and those on a diet and GL. Term placentas were obtained from UP and GD. Crude microsomal fractions were prepared by differential centrifugation and stored at -80 degrees C. The activity of the microsomes in metabolizing glyburide to the trans-4-hydroxycyclohexyl glyburide (THCGL) and cis-3-hydroxycyclohexyl glyburide (CHCGL) was determined and quantified using high-performance liquid chromatography-mass spectrometer (HPLC-MS). The activity of the placental microsomes varied widely between individual placentas in each group. The median values (pmol.mg (-1) P.min (-1)) for the rates of THCGL formation were 0.34, 0.3, and 0.23 for placentas of UP, GD on diet, and GD on GL and a diet, respectively. The median values for CHCGL formation were 0.13 for UP, 0.11 for GD on a diet, and 0.10 (pmol.mg (-1) P.min (-1)) for GD on GL and a diet. A pool of individual microsomal fractions from each group was prepared and its activity revealed the following: greater formation of THCGL in the UP (0.36 +/- 0.10) than GD (0.22 +/- 0.03) ( P = 0.058 for GD on a diet, 0.04 for GD on GL). There was greater formation of CHCGL in UP (0.26 +/- 0.04) than GD (0.12 +/- 0.003) ( P < 0.006). There was no difference in GD on a diet and GD on GL plus diet. We concluded that the apparent differences in the formation of metabolites may be statistically significant, but it is unlikely to be of physiological importance, given the sample size and other experimental factors. Therefore, a more comprehensive investigation is underway.  相似文献   
105.
Objective To demonstrate the association between genital endometrial tuberculosis and Asherman's syndrome. Materials and methods A total of 28 women who underwent hysteroscopy with or without laparoscopy for suspected Asherman’s syndrome from symptoms (amenorrhoea or oligomenorrhoea, and or primary or secondary infertility) and who were found to have genital tuberculosis on endometrial biopsy (histopathology or culture) or positive polymerase chain reaction (PCR) on endometrial aspirate or positive findings of tuberculosis on laparoscopy or hysteroscopy were enrolled in this retrospective study. Results The mean age and parity were 26.5 years and 0.3, respectively. There was past history of TB in 67.8% women. All women had menstrual dysfunction, with oligomenorrhoea and hypomenorrhoea in 16 (57%) women and amenorrhoea in 12 (42.8%). All women had primary (n = 19, 67.8%) or secondary (n = 9, 32%) infertility. On hysteroscopy, there were various grades of adhesions in all women, with grade I in 17.8%, grade II in 28.5%, grade III in 28.5% and grade IV in 17.5% women. Only four women (14.3%) had open ostia, while others had bilateral (28.5%) or unilateral (21.3%) blocked ostia or inability to see ostia (28.5%). On laparoscopy performed on 18 women, there were varying grades of adhesions in 16 (88.8%) women, with beading (33.3%), tubercles (33.3%), caseation (11.1%) and tubo-ovarian masses (11.1%). The diagnosis of genital TB was made by histopathology (tuberculous granuloma) on endometrial biopsy in 28.6%, positive culture in 3.6%, positive polymerase chain reaction (PCR) in 46.4% and observation of tubercles, beading or caseation on laparoscopy in 17.8% or shaggy cavity with caseation on hysteroscopy in 3.6% women. Conclusion Genital tuberculosis appears to be an important and common cause of Asherman's syndrome in India, causing oligomenorrhoea or amenorrhoea with infertility.  相似文献   
106.
107.
108.
The effect of acute and subchronic experimental aflatoxicosis on blood clotting activity and platelets was evaluated. Male New Zealand White rabbits (weighing 2.4-3.2 kg each) were used. In Experiment 1, 19 rabbits were given orally 0.05 mg of aflatoxin B1 (AFB1)/kg of body weight daily from Day 0 through Day 23. Blood samples were collected before dosing and on Days 2, 5, 9, 12, 16, 19, and 23 of the experimental period. In Experiment 2, 40 rabbits were given a single dose of 0.4 mg of AFB1/kg of body weight. Blood samples were collected before dosing and at 12, 24, 36, and 48 hr after dosing. When compared to baseline and control animal values, one-stage prothrombin times and activated partial thromboplastin times of aflatoxin-dosed rabbits were lengthened, and there was a statistically significant decrease in fibrinogen, Factor IX, VIII, and V activities. Platelet counts were significantly increased in subacutely exposed rabbits, and platelet size was decreased in single high-dose treated groups. Factor deficiencies were attributed to a combination of decreased factor synthesis from hepatic insufficiency and consumptive coagulopathy or primary fibrinolysis.  相似文献   
109.
The selection of a facile, eco-friendly, and effective methodology is the need of the hour for efficient curing of the COVID-19 virus in air, water, and many food products. Recently, semiconductor-based photocatalytic methodologies have provided promising, green, and sustainable approaches to battle against viral activation via the oxidative capabilities of various photocatalysts with excellent performance under moderate conditions and negligible by-products generation as well. Considering this, recent advances in photocatalysis for combating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are inclusively highlighted. Starting from the origin to the introduction of the coronavirus, the significant potential of photocatalysis against viral prevention and -disinfection is discussed thoroughly. Various photocatalytic material-based systems including metal-oxides, metal-free and advanced 2D materials (MXenes, MOFs and COFs) are systematically examined to understand the mechanistic insights of virus-disinfection in the human body to fight against COVID-19 disease. Also, a roadmap toward sustainable solutions for ongoing COVID-19 contagion is also presented. Finally, the challenges in this field and future perspectives are comprehensively discussed involving the bottlenecks of current photocatalytic systems along with potential recommendations to deal with upcoming pandemic situations in the future.

Photocatalysts are green, eco-friendly, clean and sustainable and could be a solution to combat COVID-19 because of potential features of various types of metal oxides against viral inactivation via the generation of reactive oxidative species.  相似文献   
110.
Massive ovarian edema is an uncommon benign condition affecting young females predominantly those in the child bearing age group and preadolescent girls. Its clinical and radiologic overlap with ovarian neoplasms and torsion which require surgical intervention makes it imperative for the radiologist to consider this entity preoperatively as preserving fertility is vital in this young age group. We report a case of massive ovarian edema, a rare presentation in a patient with inferior vena cava web and consequent Budd Chiari Syndrome, an association previously unreported in literature.  相似文献   
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