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71.
Philip Avner Maja Bućan Danielle Arnaud Hans Lehrach Ulf Rapp 《Somatic Cell and Molecular Genetics》1987,13(3):267-272
The localization of the A-rafcellular oncogene on the mouse X chromosome has been determined using Xbal-restricted DNAs prepared from progeny of an interspecies backcross between the B6.CBA.R1 and the Spe/Pas mouse strains. This localization to the proximal part of the mouse X chromosome has been confirmed by the use of somatic cell hybrids, carrying partially deleted X chromosomes and suggests that the A-raf oncogene localizes to a region lying some 10–17 centimorgans proximal to the hypoxanthine phosphoribosyltransferase (Hprt) gene between the locus DXPas4and the locus DXPas7defined by the cross-reacting human X chromosome-specific probe DXS32 (M2C). This localization on the mouse X chromosome is compatible with the presence of the A-rafoncogene on the short arm of the human X chromosome between the centromere and Xp21. 相似文献
72.
Marija Čarman-Kržan 《Inflammation research》1986,18(1-2):120-123
Agonist interaction with histamine H1-receptor in [3H] mepyramine bovine aortic membranes labeled with [3H] mepyramine is selectively regulated by cations and guanine nucleotides. GTP and his nonhydrolisable analog Gpp(NH)p' markedly decrease histamine affinity for [3H] mepyramine binding sites. The effect of GTP is reversed in the presence of divalent cation, magnesium. Calcium and sodium ions have little effect on histamine binding whereas magnesium ions decrease the affinity of histamine for the radioantagonist binding sites about tenfold.GTP has little effect on [3H] mepyramine binding and the interaction of H1-antagonist triprolidine with histamine H1-receptors. The above results indicate that the effect of guanine nucleotides, mono and divalent cations involves the effect on membrane signal transducing mechanism probably GTP-binding protein(s) cation regulatory site(s) rather than receptor binding site directly. 相似文献
73.
Karacaoğlu S Timur S Telefoncu A 《Artificial cells, blood substitutes, and immobilization biotechnology》2003,31(3):357-363
Arginase and urease enzymes were immobilized on the surface of pH electrode by using gelatin membrane which is then cross-linked with glutaraldehyde. Sensor response was maximum when 2.5 mM, Tris-HCl buffer (pH 8.5) was used at 25 degrees C. The biosensor response depends linearly on arginine concentration between 0.025-0.310 mM with response time 10 min. Furthermore, application of the system for the arginine detection in serum samples was also tested. 相似文献
74.
Morphology of the lumbar spinal canal in normal adult Turks 总被引:2,自引:0,他引:2
Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified. 相似文献
75.
Clinical, electrophysiological and magnetic resonance imaging findings in carpal tunnel syndrome 总被引:1,自引:0,他引:1
Musluoğlu L Celik M Tabak H Forta H 《Electromyography and clinical neurophysiology》2004,44(3):161-165
OBJECTIVE: To assess magnetic resonance imaging (MRI) findings in carpal tunnel syndrome (CTS) and to compare them with electrophysiological findings. METHODS: Routine motor and sensory nerve conduction examinations and needle EMG were performed in 42 hands of 22 patients, who were clinically diagnosed as having CTS in at least one wrist. RESULTS: Of 29 wrists with clinically and electrophysiologically confirmed CTS, MRI could detect abnormality in 18 wrists (62%). Median nerve was found to be abnormal in MRI in 1 of 2 wrists with suspected clinical symptoms and proven CTS by electrophysiological examination. MRI was abnormal in 1 of 4 wrists with normal clinical and electrophysiological examination. MRI was abnormal in 46, 7% of wrists with mild CTS, in 61.6% of moderate CTS and in 100% of severe CTS. Volar bulging of the flexor retinaculum was detected in a single wrist with severe CTS. Enlargement of median nerve was observed in 3 of 5 severe CTS. CONCLUSION: MRI could be useful in the diagnosis of unproven cases in CTS. It also provides anatomical information that correlate well with electrophysiological findings in regard of the severity of median nerve compression. 相似文献
76.
Slobodan Jarić Dušan Ristanović Daniel M. Corcos 《European journal of applied physiology》1989,59(5):370-376
Summary Kinematic variables of the vertical jump (jumping height, jump phase durations and joint angles) were measured on 39 male
physical education students. In addition, kinetic parameters of the hip and knee extensors, and of the plantar flexors (maxima
voluntary force and its rate of development) were recorded on the same subjects, in isometric conditions. The results demonstrated
significant positive correlations between kinetic parameters of the active muscle groups and jumping height (r=0.217−0.464). The dominant effect on these correlations was due to the knee extensors. Correlations between these parameters
and the duration of the jump phases were much weaker. Correlation coefficients between kinetic parameters and limb angles
in the lowest body position showed that fast force production in one muscle group was related to a significant decrease in
the joint angles of distant body segments. Multiple correlation coefficients between leg extensor parameters and kinematic
variables (ranging between 0.256 for the duration of the counter-movement phase and 0.616 for jump height) suggested that
kinetic parameters could explain more than a quarter of the variability of this complex human movement. Therefore, the conclusion
was drawn that an extended set of measurements of the relevant musculo-skeletal system parameters could predict a considerable
amount of the variability of human movement. However, high correlation coefficients between the same kinetic parameters of
different muscle groups suggest that not all active muscle groups have to be included in the measurements. 相似文献
77.
Gürpinar OA Tuzlakoğlu K Onur MA Tümer A Serdar MA Unal N Pişkin E 《Journal of biomaterials science. Polymer edition》2003,14(6):589-600
In this study, attachment and growth of Baby Hamster Kidney (BHK) cells on ethylene diamine (EDA)-plasma-treated poly(L-lactide/epsilon-caprolactone) biodegradable copolymer films were investigated. The co-polymer (Mw: 58000; Mn: 35000 and PI 1.60) was synthesised by ring-opening polymerization of the respective dimers with using stannous octoate as the catalyst. The final ratio of L-lactide to epsilon-caprolactone obtained by 1H-NMR was 87:13. The co-polymer films were treated with the EDA-plasma in a glow-discharge apparatus. The BHK-30 cell line was cultured on plain and EDA-plasma-treated films and their pre-wetted forms (with ethanol and/or cell culture medium before use). Cell attachment and growth were followed. Alkaline phosphatase (ALP) activity and glucose uptake in cell culture medium were also investigated. There was no attachment in the first 12 h. Glow-discharge treatment increased significantly the attachment and growth. Pre-wetting with ethanol and cell culture medium was also increase significantly both the attachment and growth. 相似文献
78.
Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>
Abdulkadir Bayir A. Necdet Sirkecioğlu Harun Polat N. Mevlüt Aras 《Comparative clinical pathology》2007,16(2):119-126
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in
winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate
dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz,
which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively
affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters
are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal
changes of blood biochemistry in fish. 相似文献
79.
Nina Krajcar Lorna Stemberger Mari Anja urina Sanja Kure
i Filipovi Vladimir Trkulja Sran Rogli Goran Teovi 《Croatian medical journal》2020,61(6):491
MethodsData on patients aged ≤19 years with a positive SARS-CoV-2 PCR test recorded in the period March 12-May 12 (first wave) and June 19-July 19, 2020 (second wave) were retrospectively analyzed. The periods were separated by several weeks with no incident cases.ResultsWe analyzed data on 289 children and adolescents (6.5% of all cases; incidence rate [IR] = 3.54, 95% confidence interval [CI] 3.14-3.97/million person-days), 124 in the first wave (IR = 2.27) and 165 in the second wave (IR = 6.37): IRR second/first = 2.71 (2.13-3.44). During the first wave, the incidence was highest in infants (IR = 3.48), while during the second wave it progressively increased to IR = 7.37 in 15-19-year olds. Family members were the key epidemiological contacts (72.6% cases), particularly during the first wave (95.8% vs 56.3%). Overall, 41.3% patients were asymptomatic, 25.3% in the first and 52.6% in the second wave. Age 15-19 years (vs younger) was associated with a higher (RR = 1.26, 1.02-1.54) and infection in the second wave with a lower probability (RR = 0.66, 0.53-0.81) of being symptomatic. The most common symptoms were fever, cough, and rhinorrhea. In children aged ≥7 years, headache, anosmia/ageusia, and sore throat were also recorded. Only one child suffered a severe disease. All but 18 (7.8%) children were treated only symptomatically, and all fully recovered.ConclusionA large proportion of SARS-CoV-2 PCR-positive children/adolescents were asymptomatic. The associated disease was predominantly mild, comparably so in the first and second pandemic wave.Since the late December 2019, coronavirus disease 2019 (COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread quickly worldwide and as of early December accounts for more than 65 million cases diagnosed in more than 200 countries (1). At this point, the most affected countries in Europe are Russia, Spain, France, United Kingdom (UK), and Italy with consequently the highest mortality rates. The first case in Croatia was reported in the late February 2020, and within the next two months the infection expanded nationwide. During this first epidemic wave, Croatia was under a one-month lockdown, which rapidly decreased the disease incidence, and only a few newly diagnosed cases were reported between May 25 and June18, 2020. Easing of restrictions increased the incidence in late June, causing a second wave of COVID-19 in Croatia, with >147 000 cases reported so far (1,2).Over the last two decades, there were two other coronavirus outbreaks. Severe acute respiratory syndrome coronavirus appeared in 2002, affecting around 8000 people, with 10% mortality. Children (4 months-17 years) accounted for <0.02% of total cases, and there was no reported death in this age group. During the outbreak of the Middle East respiratory syndrome coronavirus, around 2300 people were infected, and children (<19 years of age) were rarely affected as well (2% of total cases; 2 reported deaths) (3,4). COVID-19 has exhibited a similar epidemiological pattern. Although early reports from China, Italy, and the United States (US) suggested that children and adolescents accounted for only 1%-2% of the overall COVID-19 cases (5-7), later reports around the world indicated a higher proportions of pediatric cases, between 1%-8% (8-10). Children of all ages can be affected by SARS-CoV-2 infection, but in contrast to other respiratory viruses, they usually suffer a mild or asymptomatic infection. Compared with adults, severe infections and fatal outcomes in children are rare, and several immunopathological mechanisms could be responsible for such differences in disease severity (11). Although many studies have reviewed the features of adults with COVID-19, overall data regarding pediatric cases are scarce, and most of them are reports from China and the US, with only a few studies describing disease in children from European countries.We aimed to describe epidemiological and clinical features of children and adolescents with COVID-19 confirmed by the polymerase chain reaction (PCR) test for SARS-CoV-2 in Croatia and to assess potential differences between the first (March-May 2020) and second (on-going) pandemic wave (June-July 2020). 相似文献
80.
Sönmez AS Yasar L Savan K Koç S Ozcan J Toklar A Yazicioğu F Akgün A Sut N 《Human reproduction (Oxford, England)》2005,20(1):175-179
BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS. 相似文献