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71.
72.
Depression symptomatology was assessed up to four times at 2-year intervals on a sample of 2100 Danish twins initially aged 70 years and older. Data were analyzed using the biometric growth model approach proposed by Neale and McArdle (2000). Results show that occasion-specific depression is moderately and equally heritable in men and women (occasion-specific estimates of heritability ranged from 22% to 37%). Estimates of phenotypic variance, genetic variance, and heritability did not vary systematically across waves. In the best-fitting growth model, depression symptomatology was accounted for by two factors: (1) a level (i.e., average) effect that was highly heritable (estimate of 69% in women and 64% in men) and reflected overall vulnerability, and (2) a residual effect that was nonheritable and reflected occasion-specific circumstances that could either exacerbate or moderate inherited vulnerability. Attempts to identify specific genetic contributions to depression might profitably focus on average levels across multiple assessments, while attempts to identify specific environmental effects might profitably focus on deviations about this average.  相似文献   
73.
74.
The distribution of carcinoembryonic antigen (CEA) in human gastric adenocarcinoma cell lines (HPE-GAC-3 cells and HPE-GAC-2 cells) was determined immunohistochemically by indirect peroxidase-labeled antibody method at the light and electron microscopic levels. In GAC-3 cells that proliferated as non-adherent single cells, CEA was located in the perinuclear spaces, the endoplasmic reticulum, Golgi apparatus, vesicles, multivesicular body (MVB) and entire plasma membrane. Membrane CEA was shown to be internalized into MVB in GAC-3 cells. In GAC-2 cells that form an acinus, CEA was predominantly present along the microvilli of the lumina) surface and in glycocalyceal bodies, the vesicles which bud from the microvilli into the lumen. These results suggest that in poorly differentiated cancer cells CEA is transported over the entire cell surface, retained on the membrane and accumulated Into the cell by way of the MVB, but in well differentiated cancer cells the newly synthesized CEA is rapidly and predominantly transported to the luminal surface and rapidly released from the membrane into the lumen by way of the glycocalyceal body.  相似文献   
75.
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer.  相似文献   
76.
Despite extensive genomic scans, linkage studies of multiplex pedigrees have been unable to produce replicable evidence of genes predisposing to schizophrenia. This indicates that it is unlikely that a single gene accounts for a majority of cases of schizophrenia, even in multiplex pedigrees. It is most likely that schizophrenia is caused by the nonlinear interaction of multiple genetic and environmental factors influencing brain development and function. This conclusion has strong implications for the design of linkage and association studies. Recently designed linkage studies involve several improvements to deal with extensive locus heterogeneity and multiplicative interaction. These improvements include much larger samples of pedigrees, systematic ascertainment and sequential extension rules, and standardized procedures at multiple sites to facilitate collaboration and replication. Future improvements are likely to require advances in the assessment of clinical and neurobiological variability in multiplex pedigrees, more systematic environmental assessment, and advances in analytic methods to deal with multiplicative interaction. Rather than focusing only on schizophrenia as one or more discrete disorders, future linkage efforts should also consider the etiology of individual clinical syndromes or dimensional components of risk that interact to cause the complex pattern of syndromal comorbidity observed within schizophrenics and their families. © 1994 Wiley-Liss, Inc.  相似文献   
77.
Summary The effects of a COMT-inhibitor, U-0521, and a MAO-B-inhibitor, l-deprenyl, on L-dopa-induced circling behaviour were compared in 6-OHDA-lesioned rats. The actions of U-0521 and l-deprenyl on the anticataleptic effect of L-dopa were also studied. Both U-0521 and l-deprenyl were found to potentiate L-dopa-induced circling behaviour and anticataleptic effect of L-dopa. In both test systems the L-dopa potentiation of l-deprenyl was longer-lasting than that caused by U-0521. Thus inhibition of COMT, like inhibition of MAO, is able to enhance the central effects of L-dopa. This principle might be beneficial in the treatment of Parkinson's disease especially if COMT-inhibitors with greater performance can be developed.  相似文献   
78.
A single topical instillation of clonidine-3H HCl solution (0.2%) was administered to the rabbit eye (30 μl) in order to study the drug's ocular pharmacokinetics. Seven different tissues and plasma were excised and assayed for drug over 180min. By 45–60 min pseudoequilibrium is reached for the cornea, iris/ciliary body, and aqueous humor. Thereafter, drug levels in these tissues decline in parallel. The data are fit separately to a physiological model and a classical diffusion model for which seven ocular tissue compartments and a plasma reservoir are constructed for each model. Clearance terms and distribution equilibrium coefficients are determined from the tissue level data and used as parameters in fitting the mass balance differential equations representing the physiological model. The model parameters can also be fit to a 0.4% single dose. In a separate experiment, a topical infusion technique was designed to provide a constant rate input to the cornea until an apparent steady state was reached in aqueous humor at 55 min. Aqueous humor levels were assayed for clonidine over the infusion and postinfusion periods. The physiological model parameters are fit to the topical infusion data and show good agreement between the predicted and experimental data. The classical model is too complex to fit the data to integrated exponential equations primarily because the method of residuals is inadequate in determining a sufficient set of initial estimates. This is overcome by dividing the eight-compartment model into seven fragmental models, each representing one to five compartments. A stepwise procedure is developed in which initial estimates are obtained for each separate fragmental model and refined. The refined parameter values can then be used as initial estimates for the complex model. Differential equations for the complex model are fit simultaneously to tissue levels representing each compartment. By observation, the classical model fit the data more closely than the physiological model. Statistical moment theory is also applied to the topical infusion data to determine ocular pharmacokinetic parameters for clonidine. The calculated values are: corneal absorption rate constantk a , 0.00139 min?1; aqueous humor elimination rate constantk 10 , 0.0658min?1; mean residence timeMRT d , 35.6 min; apparent steadystate volume of distributionV ss, 0.530 ml; and ocular clearanceQ e , 14.9 =μl/min. The fraction absorbed from the single instillation is estimated as 0.0163.  相似文献   
79.
Zusammenfassung Anhand einer prospektiven, auslesefreien Serie von 22 Patienten mit perforierten Ulcera im Gastroduodenalbereich verweisen wir auf die begrenzte diagnostische Aussagekraft einfacher anamnestischer, klinischer und radiologischer Daten. Lediglich bei acht Patienten (36%) ergaben sich wesentliche Indizien aus Krankengeschichte und Aufnahmebefund. Bei 16 Patienten (73%) verriet die Thoraxübersichtsaufnahme durch Nachweis einer subphrenischen Luftsichel eine Perforation im Magen-Darm-Trakt. Die Ultraschalluntersuchung wird als bedeutungsvolle Ergänzungsmethode vor allem in der diagnostischen Abklärung radiologisch negativer Ulcusperforationen vorgestellt und diskutiert. Dabei werden die sonographisch faßbare flüssigkeitsbedingte Magendistension sowie das Magenwandödem als unspezifische Kriterien gewertet. Der Objektivierung einer pathologischen Magenkokarde kommt bei gleichzeitigem Nachweis freier Luft und/oder extraluminärer Ingesta sowie freier echoloser Transsudatflüssigkeit pathognomonische Beweiskraft zu. Selbige Ultraschallkriterien erlaubten im einschlägigen Krankengut bei 16 Patienten (73%) eine definitive Diagnose und erfaßte 4 Patienten mit negativem Röntgen. Die kombinierte Analyse radiologischer und sonographischer Befunde führte somit bei 20 Patienten (91 %) unverzüglich zur korrekten Diagnose.
Perforated peptic ulcer: Diagnosis and assessment by sonography
Summary In a prospective unselected series of 22 patients with perforated gastroduodenal ulcers the diagnostic efficacy of clinical and radiologic data was modest. In eight patients only (36%), clinical data yielded sufficient evidence; in 16 patients (73%), plain X-ray demonstrated subphrenic gas. Sonography was proven to be a major advance, especially rewarding in the diagnosis of perforations with negative plain X-ray. Gastric distention and stomach wall edema are unspecifc sonographic criteria, whereas objectivation of a pathologic stomach cockade in the presence of free gas, extraluminary ingesta or echofree fluid in the peritoneal cavity are pathognomonic data. These criteria yielded a definite diagnosis in 16 patients (73%) including four patients with negative X-ray. The combined analysis of radiologic and sonographic findings yielded an immediate correct diagnosis in 20 patients (91%).
  相似文献   
80.
糖尿病足溃疡是糖尿病严重的破坏性并发症,致残率及致死率逐年增高,严重威胁人类身心健康。中医药治疗糖尿病足溃疡,注重辨证论治与整体观念相结合,不仅能改善中医证候,更能在加速创面愈合的同时减少创面的复发,一定程度上延缓了糖尿病足溃疡的进一步恶化,降低其致残率及致死率。现代研究发现,糖尿病足溃疡难以愈合与各种细胞因子如炎症因子、生长因子、趋化因子等分布异常密切相关;随着现代医学对中医药研究的不断深入,中药单体及复方调控细胞因子治疗糖尿病足溃疡已成为研究热点,该文通过对目前国内外研究现状进行归纳,得出以下总结:(1)芝麻酚、栀子苷、当归补血汤、紫朱软膏等调节肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1、IL-6、IL-10等炎症因子,抑制创面炎症。(2)白芷、丹酚酸B、四效散、壮药拔毒生肌膏等调节血管内皮生长因子(VEGF)、血小板衍生生长因子(PDGF)、转化生长因子(TGF)、表皮生长因子(EGF)等生长因子,促进创面胶原沉积及血管新生。(3)芍药苷、隐丹参酮、蜂毒、回阳生肌汤等调节CXC趋化因子配体(CXCL)1、CXCL2、CC趋化因子配体(CCL)2、CCL3、基质细胞衍生...  相似文献   
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