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21.
下消化道出血221例分析 总被引:4,自引:2,他引:2
0 引言 下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1 临床资料 男 12 0例 ,女 10 1例 ,年龄 14~ 72 (平均 42 )岁 ,病程 16 h~ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1… 相似文献
22.
A variety of lasers are available for the treatment of pigmented and vascular lesions. This paper presents our preliminary evaluation of the Q-switched 532 nm Con-Bio laser (Continuum Biomedical, Livermore, CA) in a murine model. Mice were anesthetized with intraperitoneal pentobarbital. Laser impacts (10 nsec, 150 mJ max.) were created on the ears at fluences of 1.5, 2, 3, 4, 5, and 6 J/cm 2. Acute study animals were sacrificed 15 min postinjury. Tissues were fixed in formalin and examined via light microscopy. Chronic study animals were allowed to heal for 3 weeks postoperatively. Parameters analyzed included the presence or absence of blistering, hemorrhage, visual assessment of thermal injury, microscopic evidence of vascular coagulation, or disruption and cosmesis. Acute vascular disruption and coagulation were present in all samples. Healing and cosmesis were good at all fluences tested. Tests of the laser in a prefocused mode produced a tissue cavitation effect with a depth of coagulation of 0.73 +/- 0.44 mm and hemorrhage of 0.68 +/- 0.41 mm. A chronic study of the vascular effect on larger vessels (1-2 mm) was conducted on a rabbit ear. Acute disruption was observed, however, all vessels were recanalized when examined grossly and histologically at 3 weeks. These preliminary results suggest that this new laser may be useful for the treatment of cutaneous vascular lesions. Further studies and clinical trials are warranted. 相似文献
23.
Avissar S Schreiber G Nechamkin Y Neuhaus I Lam GK Schwartz P Turner E Matthews J Naim S Rosenthal NE 《Archives of general psychiatry》1999,56(2):178-183
BACKGROUND: Information-transducing heterotrimeric G proteins have been implicated previously in the mechanism of action of mood stabilizers and in the pathophysiology of mood disorders. Mononuclear leukocytes of patients with unipolar and bipolar depression have been characterized by reduced measures of the stimulatory and inhibitory G proteins. In this study, patients with seasonal affective disorder (SAD) were measured for mononuclear leukocyte G protein levels while depressed during the winter, following light therapy, and in remission during the summer. METHODS: Twenty-six patients with SAD and 28 healthy subjects were assessed in the study. The immunoreactivities of Gs alpha, Gi alpha, and Gbeta subunit proteins were determined by Western blot analysis of mononuclear leukocyte membranes with selective polyclonal antibodies for the various G subunit proteins, followed by densitometric quantitation using an image analysis system. RESULTS: Untreated patients with SAD and winter, atypical-type depression showed significantly reduced mononuclear leukocyte immunoreactive levels of Gs alpha and Gi alpha proteins, similar to previous observations in patients with nonseasonal major depression. The reduced G protein levels were normalized with 2 weeks of light therapy. The same patients while in remission during the summer had G protein levels that were similar to those of healthy subjects. CONCLUSIONS: G protein-immunoreactive measures in patients with SAD are suggested as a state marker for winter depression, which is normalized by light treatment and during the summer. We speculate that light may exert its effects via normalization of transducin (Gt protein) levels, which are thought to be reduced in winter depression. 相似文献
24.
Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells 总被引:7,自引:5,他引:7
Cell to cell communication via gap junctions is essential in the
maintenance of the homeostatic balance of multicellular organisms. Aberrant
intercellular gap junctional communication (GJIC) has been implicated in
tumor promotion, neuropathy and teratogenesis. Oxidative stress has also
been implicated in similar pathologies such as cancer. We report a
potential link between oxidative stress and GJIC. Hydrogen peroxide, a
known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells
with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible
as indicated by the complete recovery of GJIC with the removal of H2O2 via
a change of fresh media. Free radical scavengers, such as t-butyl alcohol,
propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2,
which indicated that the effects of H2O2 on GJIC was probably not a
consequence of aqueous free radical damage. The depletion of intracellular
GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of
glutathione- sufficient cells with H2O2 resulted in the
hyperphosphorylation of connexin43, which is the basic subunit of the
hexameric gap junction protein, as determined by Western blot analysis.
TPA, a well-known tumor promoter, also inhibits GJIC via
hyperphosphorylation of GJIC, which is a result of protein kinase-C
activation. However, H2O2 also induced hyperphosphorylation in
GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism
of GJIC inhibition must be different from the TPA-pathway and involves GSH.
相似文献
25.
Abdulla Watad Nicola Luigi Bragazzi Mohammad Adawi Howard Amital Shaye Kivity Naim Mahroum 《Autoimmunity》2017,50(4):269-274
Autoimmunology is a super-specialty of immunology specifically dealing with autoimmune disorders. To assess the extant literature concerning autoimmune disorders, bibliometric and scientometric analyses (namely, research topics/keywords co-occurrence, journal co-citation, citations, and scientific output trends – both crude and normalized, authors network, leading authors, countries, and organizations analysis) were carried out using open-source software, namely, VOSviewer and SciCurve. A corpus of 169,519 articles containing the keyword “autoimmunity” was utilized, selecting PubMed/MEDLINE as bibliographic thesaurus. Journals specifically devoted to autoimmune disorders were six and covered approximately 4.15% of the entire scientific production. Compared with all the corpus (from 1946 on), these specialized journals have been established relatively few decades ago. Top countries were the United States, Japan, Germany, United Kingdom, Italy, China, France, Canada, Australia, and Israel. Trending topics are represented by the role of microRNAs (miRNAs) in the ethiopathogenesis of autoimmune disorders, contributions of genetics and of epigenetic modifications, role of vitamins, management during pregnancy and the impact of gender. New subsets of immune cells have been extensively investigated, with a focus on interleukin production and release and on Th17 cells. Autoimmunology is emerging as a new discipline within immunology, with its own bibliometric properties, an identified scientific community and specifically devoted journals. 相似文献
26.
Albert Chan Patrick HY Chung Ronnie TP Poon 《World journal of gastroenterology : WJG》2014,20(29):10208-10211
An insufficient future liver remnant(FLR)is associated with post-hepatectomy liver failure.Associating liver partition and portal vein ligation for stage hepatectomy(ALPPS)has been shown to be effective for the induction of rapid FLR hypertrophy so as to improve the resectability in patients with insufficient FLR.We hereby report our experience of this novel approach for a 6-year-old patient with hepatoblastoma.Computed tomography showed a hepatoblastoma measuring12.5 cm×9.9 cm×11.7 cm in the right liver(Couinaud segmentⅣ,ⅤandⅧ).Volumetric assessment of the FLR i.e.,left lateral section was 112.6 mL i.e.,21.2%of the estimated total liver volume.In view of the small-for-size FLR,ALPPS was contemplated.An anterior approach was adopted for the in-situ parenchymal split without mobilisation of the right liver.FLR volumetry on the seventh postoperative day was 160.7 mL,which represented a 46.1%gain in volume,and a FLR/ESLV ratio of 30.2%.A right trisectionectomy was performed on the eighth postoperative day.Postoperative recovery was uneventful.Patient was discharged on day 16 after the first operation.To our knowledge,this was the first report that showed the applicability of ALPPS to a paediatric patient. 相似文献
27.
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29.
Suleyman Cuneyt Karakus Sevgi Buyukbese Sarsu Coskun Celtk Selim Gokce Naim Koku 《Pediatrics international》2015,57(2):304-307
Gastrointestinal hemorrhage in children is a critical condition that demands quick and effective management. The differential diagnosis of gastrointestinal hemorrhage is wide. Heterotopic pancreas is a rare congenital anomaly and usually discovered incidentally. It is generally asymptomatic, but symptoms may occur when complicated by inflammation, bleeding, obstruction or malign transformation. Heterotopic pancreas may present throughout the gastrointestinal tract, but it is most commonly found in the stomach, duodenum and proximal jejunum. Juvenile polyps are common during childhood and present most often with painless rectal hemorrhage. They remain the most common colonic polyps in children. Colonoscopic polypectomy is the most effective procedure in the treatment of juvenile polyps. In this study, we describe rare causes of gastrointestinal system hemorrhage in infancy and discuss some diagnostic and therapeutic approaches. 相似文献
30.
Effects of heparin on hepatic regeneration and function after partial hepatectomy in rats 总被引:4,自引:0,他引:4
INTRODUCTIONItisknownthatliverregeneratesquicklyinresponsetotisuedamage.Hepatocytegrowthfactor(HGF)hasbeenimplicatedintheregu... 相似文献