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PubMed2000

[Nitrogen dynamics in different organs of Calamagrostis angustifolia and Carex lasiocarpa in Sanjiang plain].

The dynamics of nitrogen content and storage in different organs of Calamagrostis angustifolia and Carex lasiocarpa which are dominant vegetation in swamp wetland were determined, and the utilization rate of nitrogen and its nutrient limitation in the region were analyzed. The results showed that the aboveground and underground biomass might be described by p = gamma + alpha t + beta t2 and p = a0 + b0t, respectively. The content of total N, NH4(+)-N and NO3(-)-N varied widely with different organs because of the effects of soil water, nutrient content, atmospheric temperature, vegetable feature and selective absorption to nitrogen, etc. The content of NO3(-)-N in different organs varied less than that of NH4(+)-N, and NH4(+)-N/NO3(-)-N was < 1. The N:P content less than 14 in two vegetations showed that it was N but not P was the limitation nutrient to the growth of vegetation in this region, moreover, the limitation was less in July than in August. This conclusion was also drawn from the analysis of the NH4(+)-N and NO3(-)-N content in soil.

Biomass↗
PubMed2002

[Effect of psychological factors on visceral sensation of patients with irritable bowel syndrome].

OBJECTIVE: To investigate the features of selective attention in patients with irritable bowel syndrome (IBS) and the effect of psychological hint on visceral sensation in IBS patients. METHODS: A set of 36 modified investigation cards originally developed for depression patients and including 12 cards describing gastrointestinal (GI) symptoms, 12 cards describing respiratory symptoms, and 12 cards with neutral terms, was used to investigate selective attention. 36 patients with diagnosis of IBS based on Rome II criteria, 23 patients with asthma, and 26 healthy volunteers, all without hemorrhoid, were asked to select one card from the set and put it in an envelop. A rectal balloon was inserted into the rectum of the examinees, then the balloon was inflated by pumping air so as to distend the rectum and the thresholds of initial filling sensation, evacuation sensation, urgent evacuation sensation, and utmost tolerance sensation were recorded. The examinees were asked to talk about something so as to divert their attention, and then examination of thresholds of rectal sensation and the time needed for diverting attention were recorded. After a rest for 5 approximately 10 minutes, the examinees were asked to fill the contents of selective attention they still remembered in a recording card. Then pictures of anatomy and pathology of colon were shown and conversation about gastrointestinal diseases was made to the examinees (as malignant stimuli) the changes of thresholds were recorded again. RESULTS: More terms about GI diseases were selectively recalled by the IBS patients than by asthma patients and healthy controls (all P < 0.001). During rectal distention, IBS patients had lower thresholds of initial sensation (21 +/- 5 mm Hg), evacuation sensation (36 +/- 9 mm Hg), urgent evacuation sensation (51.3 +/- 14.2 mm Hg), and utmost tolerance sensation (67 +/- 17 mm Hg) in comparison with the other two groups (both P < 0.001). After diverting the examinees' attention by talking and reading, the thresholds of the above mentioned different kinds of sensation in different groups increased significantly as compared with the basic values (all P < 0.05), in particular, the threshold of initial sensation in IBS patients increased markedly (P < 0.01). Focusing the examinees' attention on GI stimuli by reading pictures of malignant gastrointestinal diseases significantly decreased the sensation thresholds in IBS patients (P < 0.05). However, no remarkable change in the thresholds was recorded in the nonpatients. CONCLUSION: Selective attention of GI symptoms is the cognitive-behavioral characteristic of patients with IBS. Diverting the examinees' attention may decrease their response to stimuli. Psychological hint exerts significant influence on the rectal pain sensitivity of IBS patients. Psychotherapy may be helpful in treatment of IBS.

Adult↗
PubMed1993

Relationship between birth rate and infant mortality under natural reproduction situations.

The author investigates the relationship between infant mortality and the birth rate. "For this research, a number of countries with representative features are selected from different parts of the world. The study focuses on mortality and birth in these countries in the 25 year span between 1945 and 1970. A major reason for selecting these countries is that they are in a natural reproduction situation...[which] refers to a reproductive condition without any government intervention."

Birth Rate↗
PubMed1975

[Neo and postnatal development of the cerebral cortex in mice. Ultrastructural study].

Maturation in the Purkinje cell (Pk) of the cerebellar cortex of developing mice (from birth up to weaning) was investigated by structural and especially ultrastructural studies. In comparison to the adult neuron, four developmental stages were identified by studying selective morphological features (shape and size of the Pk, neuronal environment) as well as specific characteristics of neuronal constituants, particularly the "nucleus-ribosome system". The stages are: early, intermediate and late neuroblasts and young neuron. The neuronogenesis of the Purkinje cell can be summarized as follows: (a) the nuclear maturation occurs early in the development and markedly preceeds that of several organelles in the perikaryon; (b) the cytoplasmic maturation extends gradually until the young neuron state was reached. Some structures such as the granular mass and the "spotted body" in the nucleus, the nuclear envelop including its two membranes, and the ribosomal components either free or attached to the Endoplasmic Reticulum seem to exert an important role during neuronal development. Maturation processes in the Purkinje cell are generally similar in both mouse and rat and, except for some morphological and/or chronological variables, comparable in others developing nerve cells. This model of neuronal maturation is used alone or in comparison to another model of neuro-behavioral evolution which was established concommitantly. Both of these models reveal to be very useful for the evaluation of the effects induced in the developing animal following the administration of neuropsychotropic drugs such as Hallucinogens and Narcotics.

Animals↗
PubMed2002

Immunoexpression of nm23 in advanced esophageal squamous cell carcinoma.

The study was undertaken to determine the immunoexpression of protein products of nm23 genes which are thought to be potential metastasis suppressor genes, in esophageal squamous cell carcinoma, and to analyze their relationship to selected clinicopathological features (age, sex, tumour size, depth of invasion, presence of lymph nodes and distant metastasis, pathologic tumor stage, degree of cancer differentiation and vascular/lymphatic invasion), as well as to the overall survival. Immunohistochemical staining with monoclonal antibody against nm23 using LSAB2/HRP method on formalin-fixed, paraffin-embedded sections obtained from 32 tumors was performed. Eight tumors (25%) showed positive nm23 immunoexpression. There were no statistically significant differences between nm23-positive and nm23-negative groups with respect to all clinicopathological features studied. The positive nm23 status was related to a worse prognosis but this was not significant. The results may suggest that nm23-status is not associated with metastatic ability and prognosis in esophageal squamous cell carcinoma, but such thesis requires further study on a larger population.

Carcinoma, Squamous Cell↗
PubMed1992

[The course of pregnancy with placenta praevia diagnosed in the 2nd and 3rd trimester].

Selected clinical features of the course of pregnancy in 118 gravidas with placenta praevia diagnosed ultrasonographically on the first breeding were compared. The clinical features significantly connected with bleeding and the prognostic features for the way of delivery were stated. The longest bleeding was observed in patients with partial or marginal placenta praevia. The most common anterior location of low placenta praevia was connected with the lowest risk as regards the cesarean section due to hemorrhage. The earlier occurrence of the bleeding was associated with its longer duration. The time of the occurrence of the first bleeding and its duration were associated with a duration of the pregnancy and a body mass of the newborn. The recurrence of bleeding was of no prognostic importance. The appearance of the first bleeding after the 28th week of pregnancy was significantly connected with the necessity of performing a cesarean section due to hemorrhage in case of central, partial or marginal placenta praevia. In case of low-lying placenta the way on delivery was significantly related to the time of appearance of the first bleeding and the distance between the placenta and the internal os. Fisher's linear discriminative function of the two features allowed for the determination of a mathematical formula for the prognosis of the way of delivery in case of a low-lying placenta.

Adolescent↗
PubMed1998

[Antroduodenal motility in patients with gastroesophageal reflux disease].

Beside the defective lower esophageal sphincter different mechanisms may be involved pathophysiology of GERD. This study shows antroduodenal motility disorders including a lower incidence of IMC's and lower frequencies of contractions in some study periods as possible pathophysiologic feature in selected patients with atypical symptoms and increased duodenogastric reflux.

Adult↗
PubMedDate not supplied

[Evaluation of selected personality factors in patients with bronchial asthma].

Psychological factors an important role in the development and clinical course of the bronchial asthma. Therefore, an effect of the selected personality features on the course of the bronchial asthma have been studied. The study included 91 asthmatic patients and 30 persons of the control group. Three psychological tests have been used: Wiskad-MMPI. Cattell's Self-Cognition Chart, and Eysenck's Personality Inventory translated by Chojnowski. The study has shown, that asthmatic patients are characterized by the high level of anxiety and marked emotional imbalance, especially female patients. Emotions are suppressed and neglected by the asthmatic patients. These attitude should be considered in psychotherapy of such patients.

Adolescent↗
PubMed2003

Validity of hematologic parameters in identification of early and late onset neonatal infection.

This study was designed to evaluate the utility of hematological parameters and C-reactive protein (CRP) to formulate a sepsis screen to detect sepsis in early and late onset infection. Hundred and fifty neonates clinically suspected of bacterial infection, based on risk factors and/or clinical features were selected for the study. Blood was collected by venipuncture at the time of admission in all neonates. A total leukocyte count (TLC), differential leukocyte count (DLC), its derivatives [Total neutrophil count (TNC or T), ratio of immature to total neutrophil count (I/T), ratio of immature to mature neutrophil count (I/M)] and CRP were obtained. TLC = 10x10(9)/L, TNC = 8x10(9)/L, I/T = 0.16, I/M = 0.25 and CRP = 0.6 mg/dl were found to be good parameters in detection of sepsis. During the first three days of life leukopenia, neutropenia, elevated I/T ratio, elevated I/M ratio and CRP were good diagnostic aids while after 3 days of life CRP was the best single test. This emphasizes use of multiple indicators for detection of sepsis. Using these parameters a sepsis screen was formulated which detected >90% of proven early and late onset sepsis suggesting that other neonates with positive sepsis screen but blood culture negativity may have been truly infected.

Age of Onset↗
PubMed2004

[Total and specific IgE and immediate skin tests in the prognosis of atopic dermatitis].

The possibility of forecasting of atopic dermatitis (AD) course is limited. The aim of the study was to determine the prognostic usefulness of determination of total and specific IgE concentrations and the results of immediate skin tests in AD patients. The study included 480 adult patients with AD. Immediate skin tests with extracts of 18 aeroallergens and 10 food allergens were performed by PRICK method. Total IgE concentration and concentration of specific IgE (sIgE) against 13 aeroallergens and 12 food allergens were determined by the FAST method. For the assessment of the degree of pathologic process intensity the occurrence was determined of selected AD features according to Hanifin and Rajka exerting direct effect on the severity of the disease, urticaria, extensive cutaneous lesions and remission of the disease. The results were subjected to statistical analysis. In patients in whom total IgE concentration was significantly increased and/or hypersensitivity was found to aeroallergens, coexistence of atopic diseases of the airways, ectodermal defect, urticaria and extensive skin lesions was more frequently observed. Extensive skin lesions were also more frequent in patients with hypersensitivity to food allergens. The studies performed demonstrated that the diagnostic tests discussed are useful for prognostication of AD course. The presence of SIgE, positive results of immediate skin tests and high total IgE concentration prognosticate a more severe course of the disease.

Adolescent↗
PubMed1992

[Quality assessment of ginseng by chemical fuzzy pattern recognition].

Water and liquor extracts of ginseng simulating its habitual preparations used in the practice of traditional Chinese medical science were prepared from 25 samples, and data reflecting its chemical constituents as a whole were obtained by ultraviolet and visible spectrophotometry (UV-Vis), high performance liquid chromatography (HPLC), and emission spectroscopy with inductively coupled plasma source (ICP). Antifatigue, antidiuretic, and macrophage phagocytosis experiments were carried out to determine the pharmacologic actions of the extracts. Results obtained with the extracts on mice were compared mutually and with those obtained on placebo-treated ones in the respective pharmacologic experiments. Based on the results of the three pharmacologic experiments, features were selected from among the chemical data and fuzzy equations formulated hereby were solved to ascertain the effective constituents with different weights and their compatibility. Finally, correlation analysis was carried out, and a new scheme for the quality assessment of ginseng has been worked out. The methodology proposed is of general significance to the formulation of quality assessment schemes for Chinese traditional medicines and the ascertainment of their bioactive constituents.

Animals↗
PubMedDate not supplied

[Cerebrovascular disease: its relationship with cardiovascular and renal pathology in 134 clinical autopsies].

OBJECTIVE: To establish the relationship between cardiopathy and chronic nephropathy, and cerebral vascular pathology in clinical necropsies performed in adult patients. MATERIAL AND METHODS: The protocols of 861 clinical autopsies done during the lapse 1990-2000 were reviewed, of these, 134 cases with diagnosis of cerebrovascular disease (CVD) were selected. Analyzed features included: neuropathological study of CVD, renal and cardiovascular pathology, and cause of death. RESULTS: CVD represented 15.5% of all autopsies done during the study period. Ischemic CVD constituted 56.7% of the cases, whereas cases of hemorrhagic CVD accounted for 43.3% of the total. Causes included arterial hypertension (33%), atherosclerosis (19%), emboli and vascular malformations (13% each, respectively), coagulopathies (8%), angeiitis (4%), tumors (1%), and unknown origin (11%). Ischemic CVD was caused by atherosclerosis in 34.2% of the cases, lacunar infarcts in 32.8%, of embolic cause in 14.4% of the cases, angeiitis in 1.3%, and of unknown origin in 17.1% of the cases. Hemorrhagic CVD presented as intraparenchymal hematoma in 50% of the cases, as sub-arachnoid hemorrhage in 28%, as disseminated petechial hemorrhages in 19%, and intraventricular in 3% of the cases. Ischemic CVD was associated with hypertensive cardiopathy in 86.5% of the cases, and with nephrosclerosis in 51.3%, whereas hemorrhagic CVD was seen associated with the same pathological entities in 86.2% and 29.3% of the cases, respectively. Cerebral herniation was the cause of death in 2.6% of the patients with ischemic CVD, and in 74.1% of the patients with hemorrhagic CVD. CONCLUSIONS: CVD was associated with a high frequency of intercurrent pathological processes, namely hypertensive cardiopathy, atherosclerosis, nephroscleroisis, and other chronic nephropathies, that eventually interact, and constitute well known predisposing and/or concomitant factors to the cerebrovascular event

Adult↗
PubMed2004

What evidence-based undergraduate interventions promote rural health?

AIMS: This article identifies published reports of medical undergraduate rural programmes from international medical schools and investigates the features making these programmes successful in recruiting and retaining rural physicians. METHOD: Literature review. RESULTS: Ten successful programmes were identified. Common features included selective admission, curricular focus on primary care/family medicine, community-based teaching, and community/rural preceptorship. A strong association exists between rural background of the student and choice of both a rural career and a career in primary care. Medical students of rural origin with an initial interest in a generalist career are significantly more likely to enter rural practice. Community preceptorship with its high staff:student ratio has been effective in influencing students' career choices. CONCLUSIONS: The effectiveness of a medical undergraduate rural programme in preparing and recruiting physicians for rural practice does not occur with one isolated strategy but with a chronological sequence of interventions. The most effective programmes consider both pre-medical school and medical school educational factors. Medical schools would need to implement a combination of these strategies when designing a programme to maximise success.

Career Choice↗
PubMed2005

Connexins 26 and 43 correlate with Bak, but not with Bcl-2 protein in breast cancer.

Apoptosis is a process associated with development and progression of breast cancer. The association between connexins and programmed cell death has only been demonstrated in a few studies. The aim of the present study was the evaluation of Cx26 and Cx43 expression in breast cancer in correlation with Bcl-2 and Bak proteins as well as with selected clinicopathological features. Tissue samples from 71 women were examined by immunohistochemistry, using the streptavidin-biotin-peroxidase complex technique for Cx26, Cx43, Bak and Bcl-2. Cytoplasmic expression of Cx26 and Cx43 was detected in 34 (47.9%) and 61 (85.9%) of breast cancers, respectively. Bcl-2 and Bak expression was found in 59 (83%) and 50 (70%) of studied cases, respectively. We found a positive correlation between Cx26 and Bak expression (r=0.541, p<0.0001) as well as between Cx43 and Bak (r=0.589, p<0.0001), but not between the studied connexins and Bcl-2. The expression of Cx26 was not associated with age, tumor size, lymph node status or histological grade. However, we observed an association between Cx43 expression and histological grade G3 (p<0.04). Cytoplasmic localization of evaluated connexins supports the concept of alterations in connexins expression in breast cancer cells. The associations of evaluated connexins with Bak protein could suggest that connexins localized in the cytoplasm may participate in signaling apoptotic pathways.

Adult↗
PubMed2005

Use of Geographic Information Systems in the development of prediction models for onchocerciasis control in Ethiopia.

A risk assessment model was developed for onchocerciasis distribution and its control in Ethiopia using Geographic Information System (GIS) methods. GIS data analysis was done to generate 3 separate risk models using selected environmental features of (1) earth observing satellite data on Normalized Difference Vegetation Index (NDVI) and midday Land Surface Temperature (LST) prepared from AVHRR sensor data of the Global land 1-km project for the years 1992 and 1995, (2) FAO agroclimatic databases from the Crop Production System Zone (CPSZ) of the Intergovernmental Authority on Development (IGAD) sub-region of East Africa, and (3) a climate-based forecast index based on the growing degree days (GDD) and water budget concepts. Parasitological data used for the analysis were published and unpublished reports of onchocerciasis surveillance made between 1969 and 2000 in various parts of the country. Analysis of queries based on 1992 and 1995 annual wet and dry season data of the Global land 1-km project resulted in a predictive value of 95.1%, 94.0% and 96.3%, respectively, using data values extracted from buffers centered on sites above 5% prevalence. The model based on CPSZ data predicted an endemic area that best fit the distribution of sites over 5% prevalence; the query was based on CPSZ values of average altitude (442-2134 m), annual mean temperature (18-28 degrees C), annual rainfall (822-1980 mm), annual potential evapotranspiration (1264-1938 mm), rain minus potential evapotranspiration (-124 - 792 mm), average NDVI x 100 (2000-5000) and average terrain percent slope (9-34). The climate-based model based on GDD and water-budget predicted high risk to severe risk areas in the western and southwestern parts of the country. All three of the models predicted suitable areas for the transmission of onchocerciasis outside known endemic areas, suggesting the need for ground-based validation and potential application to current community-directed treatment programs with ivermectin (CDTI) for control of onchocerciasis in Ethiopia.

Agriculture↗
PubMed2005

Karyometry in rectal mucosa of patients with previous colorectal adenomas.

OBJECTIVE: To determine whether karyometric measurements taken in biopsies from histologically normal-appearing rectal mucosa could serve as a biomarker for the risk of recurrence of polyps. MATERIALS AND METHODS: Biopsies were taken from the rectal mucosa of cases with a prior history of colonic polyps at the baseline of the study. In 57 cases recurrent polyps occurred (R cases); in 72 cases no recurrent disease was found at the end of the study (NR cases). From each biopsy 100 nuclei were recorded at high resolution. After segmentation, feature extraction and selection of a discriminating subset of features, a number of discriminant functions were derived. Also, measures of nuclear abnormality were computed. RESULTS: The differences in karyometricfeature values for nuclei from biopsies of cases with recurrent or nonrecurrent disease were very small and not notably expressed in the majority of nuclei. It was possible by focusing on nuclei showing clear deviations from normal to derive a discriminant function that exhibited a shift for the NR and R data sets. The distributions of discriminant function scores were then subjected to a second-order discriminant analysis to separate cases according to recurrence status. This function showed a statistically highly significant correlation with recurrence. At one extreme of its score distribution were 11 of 57 cases that had a recurrence, and at the other extreme were 8-10 of 72 cases that had no recurrence. The distributions of nuclear abnormality values for these subsets of cases were drastically different, with an average value of 1.72 for the group that may be at high risk for another recurrence and 1.02 for the group possibly at low risk. All cases with a prior history of colonic polyps showed a nuclear abnormality deviating from normal. CONCLUSION: Measurement of a sample of 100 nuclei from the rectal mucosa will suggest, for approximately 10% of cases, that a high risk for recurrence of adenomatous polyps exists and, for a slightly lower proportion, confirm that the nuclei deviate only slightly from those from individuals with no history of colonic polyps. For the majority of cases with a prior history of adenoma, the nuclei in the biopsy show a notable deviation from normal, but the deviation is practically the same for cases that had a recurrence and those that did not. However, a tentative discriminant function (DF I,3) derived from the characteristics of the extreme cases correctly classified approximately 64% of nonrecurrent and 83% of recurrent cases using a Bayesian decision boundary.

Adenomatous Polyposis Coli↗
PubMed1991

Commonly used suture materials in skin surgery.

The ideal suture is strong, handles easily and forms secure knots. It causes minimal tissue inflammation and does not promote infection. It stretches, accommodates wound edema and recoils to its original length with wound contraction. Ideally, it is also inexpensive. Although no single suture material possesses all of these features, proper selection of sutures helps achieve better results in skin surgery. Among the absorbable sutures are catgut and treated catgut (both are used infrequently) and the synthetic sutures, which are designed for good tensile strength, easy handling and low tissue reactivity. Nonabsorbable sutures include silk (now infrequently used) and several synthetic materials designed for elasticity, easy handling, good knot security and minimal tissue irritation.

Absorption↗
PubMed1991

Wide QRS tachycardia.

Wide QRS tachycardia is a diagnostic challenge when confronted on a 12-lead electrocardiogram. The differential diagnosis includes: ventricular tachycardia; supraventricular tachycardia with aberration; and Wolff-Parkinson-White syndrome. Confronted with a wide QRS tachycardia, one must determine whether the origin is ventricular or supraventricular because the therapy will differ. The electrocardiographic findings of capture beats, fusion beats and atrioventricular dissociation are highly specific for ventricular tachycardia but not very sensitive. After careful assessment of the 12-lead electrocardiogram following selected diagnostic features, the correct diagnosis of the cause of wide QRS tachycardia can be made in about 90 percent of patients. This article contains a brief discussion of the diagnostic features of wide QRS tachycardia.

Bundle-Branch Block↗