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61.
To further understand the temporal mode and mechanisms of coronary restenosis, 229 patients were studied by prospective angiographic follow-up on day 1 and at 1, 3 and 6 months and 1 year after successful percutaneous transluminal coronary angioplasty. Quantitative measurement of coronary stenosis was achieved by cinevideodensitometric analysis. Actuarial restenosis rate was 12.7% at 1 month, 43.0% at 3 months, 49.4% at 6 months and 52.5% at 1 year. In 219 patients followed up for greater than or equal to 3 months, mean stenosis diameter was 1.91 +/- 0.53 mm immediately after coronary angioplasty, 1.72 +/- 0.52 mm on day 1, 1.86 +/- 0.58 mm at 1 month and 1.43 +/- 0.67 mm at 3 months. In 149 patients followed up for greater than or equal to 6 months, mean stenosis diameter was 1.66 +/- 0.58 mm at 3 months and 1.66 +/- 0.62 mm at 6 months. In 73 patients followed up for 1 year, mean stenosis diameter was 1.65 +/- 0.56 mm at 6 months and 1.66 +/- 0.57 mm at 1 year. Thus, stenosis diameter decreased markedly between 1 month and 3 months after coronary angioplasty and reached a plateau thereafter. In conclusion, restenosis is most prevalent between 1 and 3 months and rarely occurs beyond 3 months after coronary angioplasty.  相似文献   
62.

Background

This study aimed to determine the radiologic predictors and clarify the clinical features related to survival in patients with combined pulmonary fibrosis and emphysema (CPFE) and lung cancer.

Methods

We retrospectively reviewed the medical chart data and high-resolution computed tomography (HRCT) findings for 81 consecutive patients with CPFE and 92 primary lung cancers (70 men, 11 women; mean age, 70.9 years). We selected 8 axial HRCT images per patient, and visually determined the normal lung, modified Goddard, and fibrosis scores. Multivariate analysis was performed using the Cox proportional hazards regression model.

Results

The major clinical features were a high smoking index of 54.8 pack-years and idiopathic pulmonary fibrosis (n = 44). The major lung cancer profile was a peripherally located squamous cell carcinoma (n = 40) or adenocarcinoma (n = 31) adjacent to emphysema in the upper/middle lobe (n = 27) or fibrosis in the lower lobe (n = 26). The median total normal lung, modified Goddard, and fibrosis scores were 10, 8, and 8, respectively. TNM Classification of malignant tumors (TNM) stage I, II, III, and IV was noted in 37, 7, 26, and 22 patients, respectively. Acute exacerbation occurred in 20 patients. Multivariate analysis showed that a higher normal lung score and TNM stage were independent radiologic and clinical predictors of poor survival at the time of diagnosis of lung cancer.

Conclusions

A markedly reduced area of normal lung on HRCT was a relevant radiologic predictor of survival.  相似文献   
63.
4‐(4‐Hydroxyphenyl)‐2‐butanol (rhododendrol, RD), a skin‐whitening agent, was reported to cause skin depigmentation in some users, which is attributed to its cytotoxicity to melanocyte. It was reported that cytotoxicity to melanocyte is possibly mediated by oxidative stress in a tyrosinase activity‐dependent manner. We examined the effect of UV radiation (UVR) on RD‐induced melanocyte cytotoxicity as an additional aggravating factor. UVR enhanced RD‐induced cytotoxicity in normal human epidermal melanocytes (NHEMs) via the induction of endoplasmic reticulum (ER) stress. Increased generation of intracellular reactive oxygen species (ROS) was detected. Pretreatment with N‐acetyl cysteine (NAC), antioxidant and precursor of glutathione significantly attenuated ER stress‐induced cytotoxicity in NHEMs treated with RD and UVR. Increase in cysteinyl‐RD‐catechol and RD‐pheomelanin in NHEMs treated with RD and UVR suggested that, after UVR excitation, RD or RD metabolites are potent ROS‐generating substances and that the tendency to produce RD‐pheomelanin during melanogenesis amplifies ROS generation in melanocytes. Our results help to elucidate the development mechanisms of RD‐induced leukoderma and provide information for innovation of safe skin‐whitening compounds.  相似文献   
64.
T Shimono  S Nosaka  K Sasaki 《Brain research》1976,108(2):279-294
(1) Functional commencements of the neuronal elements in the cerebellar cortex of young rats were studied electrophysiologically by means of laminar field potential analyses in the cortex on stimulation of the cerebellar surface (Loc) and the white matter (WM). (2) The antidromic action potential of Purkinje cells on the WM stimulation was observed at one day after birth. The climbing fiber excitation of Purkinje cells on the stimulation was noted at 3 days after birth. (3) The mossy fiber-granule cell synapses were found to function at 10 days after birth and the Golgi cell inhibition of granule cells could be proved at the same time. The excitatory action of parallel fibers and the inhibitory action of basket-stellate cells on Purkinje cells appeared simultaneously at about 12 days after birth. The transverse distribution across the cerebellar folium of the basket-stellate cell inhibitory action on Purkinje cells was found to be narrow up to 60 days after birth. (4) These results concerning the dates of commencement of excitatory and inhibitory synaptic actions in the cerebellar cortex were compared with those of synaptogenesis studied morphologically, and some implications of the dates in the functional development of the cerebellar cortex were discussed.  相似文献   
65.
Transient left ventricular (LV) wall thickening is observed in patients with acute lymphocytic myocarditis. The present study was undertaken to clarify the significance of transient LV wall thickening in patients with this disease. The subjects comprised 25 patients with acute lymphocytic myocarditis. Echocardiography was used to measure the thickness of the interventricular septum (IVS) and the LV posterior wall (PW) at four time points after myocarditis onset – namely, on days 1–3, 6–8, 13–15, and 28–30 – to clarify the timing and frequency of wall thickening. The 25 patients were divided into a fulminant myocarditis group (n = 14) and a nonfulminant myocarditis group (n = 11), and the relationship between LV wall thickening and myocarditis severity was investigated. Left ventricular wall thickening was greatest on days 1–3 after myocarditis onset (IVS: 13.3 ± 3.2 mm; PW: 12.1 ± 2.6 mm), with this finding being noted in 14 of the 25 cases (56%). By days 6–8, the thickness of IVS had virtually normalized to 10.6 ± 1.6 mm (P < 0.0001) and that of PW to 10.2 ± 1.4 mm (P = 0.0006). The thickness of the IVS and PW on days 1–3 after myocarditis onset were 14.6 ± 3.7 and 13.0 ± 2.9 mm, respectively, in the fulminant group (P = 0.014), and 11.5 ± 0.9 and 10.9 ± 1.4 mm, respectively, in the nonfulminant group (P = 0.039). In lymphocytic myocarditis, LV wall thickening is greatest on days 1–3 after myocarditis onset and improves to near normal by days 6–8. Such transient LV wall thickening occurs in approximately 50% of cases. Left ventricular wall thickening was more marked in the fulminant compared with the nonfulminant group.  相似文献   
66.
A bout of eccentric exercise confers protection against subsequent bouts of the same exercise. This study investigated whether the protective effect would be produced similarly between old and young adults. Eight old men (70.5 ± 4.1 years) and ten young men (20.4 ± 2.0 years) performed two bouts of eccentric exercise of the elbow flexors (six sets of five eccentric actions) separated by 4 weeks. Changes in maximal isometric strength, range of motion (ROM), upper arm circumference (CIR), plasma creatine kinase (CK) activity, myoglobin (Mb) concentration, and muscle soreness (SOR) before, immediately after, and 1, 24, 48, 72 and 96 h following exercise were compared between bouts, and between groups by a two-way repeated measures ANOVA. Changes in the measures following the first bout were significantly (P < 0.05) smaller for the old than the young group. The young group showed significantly (P < 0.05) smaller changes in all measures following the second bout than the first bout; however, the old group had the protective effect only for ROM, Mb, and SOR. The magnitude of the effect observed for ROM and Mb concentration in the old group was significantly (P < 0.05) smaller compared with that of the young group. These results suggest that the protective effect conferred by the first bout was less for the old than the young group. This may be due to the less muscle damage after the first bout in the old subjects, but it is also possible that the protective effect of old adults does not last as long as that of young adults.  相似文献   
67.
Images of perforated choledochal cysts typically show an intraperitoneal fluid collection. We report a case with, in addition to free intraperitoneal fluid, fluid collection in the right-side anterior pararenal and perirenal spaces. Surgery confirmed the presence of a perforation at the junction of the cystic duct and the common bile duct. This perforation may explain the biliary leakage extending into the free peritoneal space as well as into the anterior pararenal space and the hepatoduodenal ligament. Anterior pararenal and perirenal spaces communicate with the infrarenal space, and this may result in extension of the fluid into the perirenal space from the anterior pararenal space.  相似文献   
68.
The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis.  相似文献   
69.
Hepatitis C virus (HCV) infection is associated with lymphoproliferative disorders. HCV infection of B cells is a predictive factor for lymphoproliferative disorders in patients with chronic hepatitis C, although its molecular mechanisms remain unknown. Epstein-Barr virus (EBV) is a B cell-tropic virus with the potential to cause lymphoproliferative disorders, and its reactivation is induced by several viruses and cytokines. The possibility that HCV infection triggers reactivation of EBV and induces lymphoproliferative disorders were investigated. Expression of EBV mRNAs was analyzed by RT-PCR in patients infected with HCV and control subjects, and correlations between reactivation of EBV and markers for lymphoproliferative disorders were investigated. BZLF1 mRNA, a starter molecule of reactivation, was detected in peripheral blood mononuclear cells from 12 of 52 (23%), patients infected with HCV and the frequency was higher than in healthy subjects [3 of 43 (9%), P = 0.032]. But the presence of the BZLF1 mRNA was not associated with an abnormality of markers for lymphoproliferative disorders. This study on BZLF1 mRNA expression among lymphoid cell subsets showed that reactivation of EBV was observed specifically in B cells. The BZLF1 mRNA disappeared following anti-viral therapy and remained negative after eradication of HCV in patients with a sustained viral response, while the EBER1 RNA, a marker for persistence of EBV, was detected throughout the therapy. Infection with HCV induces reactivation of EBV in B cells, but this reactivation was not associated directly with lymphoproliferative disorders triggered by HCV.  相似文献   
70.
Selective loss of dopaminergic neurons is the final common pathway in Parkinson's disease. Expression of Parkin associated endothelin-receptor like receptor (Pael-R) in mouse brain was achieved by injecting adenoviral vectors carrying a modified neuron-specific promoter and Cre recombinase into the striatum. Upregulation of Pael-R in the substantia nigra pars compacta of mice by retrograde infection induced endoplasmic reticulum (ER) stress leads to death of dopaminergic neurons. The role of ER stress in dopaminergic neuronal vulnerability was highlighted by their decreased survival in mice deficient in the ubiquitin-protein ligase Parkin and the ER chaperone ORP150 (150 kDa oxygen-regulated protein). Dopamine-related toxicity was also a key factor, as a dopamine synthesis inhibitor blocked neuronal death in parkin null mice. These data suggest a model in which ER- and dopamine-related stress are major contributors to decreased viability of dopaminergic neurons in a setting relevant to Parkinson's disease.  相似文献   
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