排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
Samaiya A Deo SS Thulkar S Hazarika S Kumar S Parida DK Shukla NK 《World journal of surgical oncology》2005,3(1):3-7
BACKGROUND: Malignant small bowel tumors are very rare and leiomyosarcoma accounts for less than 15% of the cases. Management of these tumors is challenging in view of nonspecific symptoms, unusual presentation and high incidence of metastasis. In this case report, an unusual presentation of jejunal sarcoma and management of liver metastasis with radiofrequency ablation (RFA) is discussed. CASE PRESENTATION: A 45-year-old male presented with anemia and features of small bowel obstruction. Operative findings revealed a mass lesion in jejunum with intussusception of proximal loop. Resection of bowel mass was performed. Histopathological findings were suggestive of leiomyosarcoma. After 3-years of follow-up, the patient developed recurrence in infracolic omentum and a liver metastasis. The omental mass was resected and liver lesion was managed with radiofrequency ablation. CONCLUSION: Jejunal leiomyosarcoma is a rare variety of malignant small bowel tumor and a clinical presentation with intussusception is unusual. We suggest that an aggressive management approach using a combination of surgery and a newer technique like RFA can be attempted in patients with limited metastatic spread to liver to prolong the long-term survival in a subset of patients. 相似文献
2.
JINDŘIŠKA BOJKOVÁ KLÁRA KOMPRDOVÁ TOMÁŠ SOLDÁN SVĚTLANA ZAHRÁDKOVÁ 《Freshwater Biology》2012,57(12):2550-2567
1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area. 相似文献
3.
Moderate alcohol consumption is associated with better endothelial function: a cross sectional study
Keiko Suzuki Mitchell SV Elkind Bernadette Boden-Albala Zhezhen Jin Grace Berry Marco R Di Tullio Ralph L Sacco Shunichi Homma 《BMC cardiovascular disorders》2009,9(1):1-5
Background
Natural heterologous valved conduits with a diameter greater than 22 mm that can be used for right ventricular outflow tract reconstruction in adults are not commercially available. The purpose of this study was to measure by ultrasonography the maximum diameter of the distended jugular veins of horses and cattle, respectively, to identify a population of animals that would be suitable for post-mortem collection of jugular veins at sizes greater than 22 mm.Methods
The study population included 60 Warmblood horses, 25 Freiberger horses, 20 Brown Swiss cows, and 20 Holstein cows (including 10 Holstein and 10 Red Holstein). The maximum cross-sectional diameter of the distended jugular veins was measured at a location half-way between the mandibular angle and the thoracic inlet. The thoracic circumference (heart girth length) was used as a surrogate of body size. The jugular vein diameters of the different populations were compared by analysis of variance and the association between heart girth length and jugular vein diameter was determined in each of the four study populations by linear regression analysis.Results
There was considerable individual variation of jugular vein diameters within each of the four study populations. There was no statistically significant relationship between thoracic circumference and jugular vein diameter in any of the populations. The jugular vein diameters of Brown Swiss cows were significantly larger than those of any of the other populations. Warmblood horses had significantly larger jugular vein diameters compared to Freiberger horses.Conclusion
The results of this study suggest that the production of bovine or equine xenografts with diameters of greater than 22 mm would be feasible. Differences between species and breeds need to be considered. However, prediction of the jugular vein diameter based on breed and heart girth length in an individual animal is inaccurate. 相似文献4.
O. V. Grishin S. V. Basalaeva N. D. Umantseva N. V. Ustyuzhaninova V. G. Grishin I. M. Mitrofanov 《Human physiology》2011,37(5):582-587
Indices of pulmonary gas exchange and heart rate (HR) have been measured in 24 healthy subjects not adapted to hypoxia after
hypoxic aerial mixture (HAM) (17, 15, 13 vol % of oxygen) respiration for 15 min. Using group data analysis, it has been shown
that hypoxia under the conditions of inhalation of 17 and 15 vol % of O2 caused no significant changes. Hypoxia under the conditions of 13 vol % of O2 inhalation is a threshold one, when ventilation (SpO2) drops below 85%. A significant increase in the lung ventilation (Ve) (10–14%, p < 0.05) and HR (11–15%, p < 0.05) have been observed in this case. Hyperpnea was accompanied by an increase in the oxygen uptake rate by 10% and carbon
dioxide release rate (10–18%, p < 0.05). On the contrary, individual data analysis showed changes in the pulmonary gas exchange indices in 90% of subjects
in the case of inhalation of 17 vol % of O2 HAM. Four response types have been found: ventilation (increase in lung ventilation), hypoxic hypometabolism (decrease in
oxygen consumption rate), and mobilization response (increase in oxygen utilization in the lungs), and anaerobic response,
which is expressed in an increase in the carbon dioxide release rate along with an increase in the respiratory quotient. All
these responses are of an individual type, but the ventilation response is developed in response to hypoxia caused by inhalation
of 13 vol % of O2 HAM and a decrease in SpO2 below 85% in more than 60% of cases. 相似文献
5.
Thomas GH; Newbern EC; Korte CC; Bales MA; Muse SV; Clark AG; Kiehart DP 《Molecular biology and evolution》1997,14(12):1285-1295
Many structural, signaling, and adhesion molecules contain tandemly
repeated amino acid motifs. The alpha-actinin/spectrin/dystrophin
superfamily of F-actin-crosslinking proteins contains an array of triple
alpha-helical motifs (spectrin repeats). We present here the complete
sequence of the novel beta-spectrin isoform beta(Heavy)- spectrin (beta H).
The sequence of beta H supports the origin of alpha- and beta-spectrins
from a common ancestor, and we present a novel model for the origin of the
spectrins from a homodimeric actin-crosslinking precursor. The pattern of
similarity between the spectrin repeat units indicates that they have
evolved by a series of nested, nonuniform duplications. Furthermore, the
spectrins and dystrophins clearly have common ancestry, yet the repeat unit
is of a different length in each family. Together, these observations
suggest a dynamic period of increase in repeat number accompanied by
homogenization within each array by concerted evolution. However, today,
there is greater similarity of homologous repeats between species than
there is across repeats within species, suggesting that concerted evolution
ceased some time before the arthropod/vertebrate split. We propose a
two-phase model for the evolution of the spectrin repeat arrays in which an
initial phase of concerted evolution is subsequently retarded as each new
protein becomes constrained to a specific length and the repeats diverge at
the DNA level. This evolutionary model has general applicability to the
origins of the many other proteins that have tandemly repeated motifs.
相似文献
6.
Comparisons of the molecular evolutionary process at rbcL and ndhF in the grass family (Poaceae) 总被引:2,自引:1,他引:1
We examine rate heterogeneity among evolutionary lineages of the grass
family at two plasmid loci, ndhF and rbcL, and we introduce a method to
determine whether patterns of rate heterogeneity are correlated between
loci. We show both that rates of synonymous evolution are heterogeneous
among grass lineages and that are heterogeneity is correlated between loci
at synonymous sites. At nonsynonymous sites, the pattern of rate
heterogeneity is not correlated between loci, primarily due to an aberrant
pattern of rate heterogeneity at nonsynonymous sites of rbcL. We compare
patterns of synonymous rate heterogeneity to predictors based on the
generation time effect and the speciation rate hypotheses. Although there
is some evidence for generation time effects, neither generation time
effects nor speciation rates appear to be sufficient to explain patterns of
rate heterogeneity in the grass plastid sequences.
相似文献
7.
8.
Grishin OV Basalaeva SV Umantseva ND Ustiuzhaninova NV Grishin VG Mitrofanov IM 《Fiziologiia cheloveka》2011,37(5):77-83
Pulmonary gas exchange, SpO2 and heart rate at 15-min hypoxia (respiration by air with 0.17; 0.15 and 0.13 oxygen fractions) have been investigated in 24 health subjects. It has been established, results of the group analysis and the results of the individual analysis had been differed. Reaction on hypoxia at the group analysis had been found only at 0.13 02 fraction. It was only hyperventilation. The individual analysis had revealed 4 types of reaction on hypoxia already at 0.17 and 0.15 02 fractions: (1) hyperventilation, (2) decrease of oxygen consumption, (3) increase of ventilation effectiveness, (4) increase of CO2 production. The mechanisms of last reaction are unknown, but we supposed it was connected with anaerobic metabolism. The reactions were detected at light hypoxia (0.17 and 0.15 oxygen fractions) in 90% health subjects when SpO2 decreased to 87-93%. The increase ventilation has been detected at hypoxia within respiration 0.13 oxygen in 60% subjects when SpO2 decreased to 83-87%, while other reactions were nearly absent. 相似文献
9.
Hannah Gardener Della David Morte Mitchell SV Elkind Ralph L Sacco Tatjana Rundek 《BMC cardiovascular disorders》2009,9(1):1-8
Background
Heterogeneity in B-type natriuretic peptide (BNP) levels, especially among individuals with acute heart failure with normal left ventricular ejection fraction (HFNEF), can cause confusion in interpreting results. We investigated the characteristics of cases of acute HFNEF with only modestly elevated BNP.Methods
One hundred forty-two patients with acute or acute exacerbation of chronic HFNEF were divided into two groups by BNP level: BNP < 100 pg/ml (NB group, n = 45) and BNP ≥ 100 pg/ml (B group, n = 97). We compared clinical findings, echocardiography results, and neurohormonal factors between these two groups.Results
In the NB group, a history of open-heart surgery (OHS) was more frequent (71% vs. 22%, p < 0.0001) and hypertension was less frequent (p = 0.0005). Left atrial diameter (LAd) was higher (p = 0.0026), while interventricular septal thickness, posterior wall thickness, relative wall thickness, left ventricular mass index were lower (p = 0.0005, p = 0.0225, p = 0.0114, p = 0.0051, respectively) in the NB group. In patients with HFNEF, a history of OHS remained an independent predictor of BNP level (< 100 pg/ml) after adjustment for hypertension, age, LAd, and interventricular septal thickness (odds ratio 3.6, p = 0.0252).Conclusion
We found associations between acute HFNEF with less elevated BNP and a history of OHS. In a patient suspected of HFNEF, a history of OHS is considered diagnostic evidence of presence of diastolic heart failure when plasma levels of BNP are less elevated. 相似文献10.
Nadezdha L. Basalaeva 《Biological trace element research》2013,154(2):244-254
The purpose of this study was to determine the content of iodine and selenium in the thyroid and pituitary glands of rats under iodine-induced blockade of the thyroid gland. Electron probe microanalysis, wavelength-dispersive spectrometry, and point analysis were used in this investigation. We also determined the expression of sodium iodide symporter and caspase 32 in the thyroid and pituitary glands and the expression of thyroid-stimulating hormone in the pituitary. The samples for iodine analysis must be thoroughly dehydrated, and for this purpose, we developed a method that produced samples of constant mass with minimal loss of substrate (human thyroid gland was used for the investigation). Normal levels of iodine and selenium were found in the thyroid, pituitary, ovaries, testes hypothalamus, and pancreas of healthy rats. The levels of iodine and selenium in I- or Se-positive points and the percentage of positive points in most of these organs were similar to those of controls (basal level), except for the level of iodine in the thyroid gland and testes. Blockade of the thyroid gland changed the iodine level in iodine-positive points of the thyroid and the pituitary glands. On the sixth day of blockage, the iodine level in iodine-positive points of the thyroid gradually decreased to the basal level followed by an abrupt increase on the seventh day, implying a rebound effect. The opposite was found in the pituitary, in which the level of iodine in iodine-positive points increased during the first 6 days and then abruptly decreased on the seventh day. Expression of the thyroid-stimulating hormone in the pituitary decreased during the first 5 days but sharply increased on the sixth day, with a minimum level of iodine in the thyroid and maximum in the pituitary, before normalization of the iodine level in both glands preceding the rebound effect. The expression of sodium iodide symporter increased during the first 4 days of blockage and then decreased in both glands. The fluctuations of the thyroid-stimulating hormone in the pituitary gland reflected the changes of iodine in the thyroid gland more precisely than the changes of sodium iodide symporter. The selenium level in the selenium-positive points changed only in the pituitary, dropping to zero on the second and fifth day of the blockade. Simultaneously, the maximum induction of caspase 32 was observed in the pituitary gland. We believe that these results may help to clarify a role of the pituitary gland in the thyroid blockade. 相似文献