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1.
On hatching from the egg, a larva of Lepidosroma hirtum Curtis constructed a tubular, sand grain case. As the larva became older it periodically added new material to the anterior of the case and, once in every instar except the 1st, cut off ⅓ to ¼ of the posterior of the case. In the 3rd instar the larva changed from adding sand grains to cutting out and attaching almost rectangular leaf panels. By the 5th instar the case was composed entirely of leaf panels. The case was then square in section and composed of one row of panels for each of the sides. The panels were not truly rectangular but convex on the leading edge and sides and concave at the back, so that the anterior convexity of one panel fitted into the posterior concavity of the panel in front. Panels were arranged with their long axes across the case. The seams between panels in the roof were half a panel length out of phase with those in the sides but in phase with those in the floor. The convex sides of a panel allowed it to overlap the seams between panels on the two adjacent sides. If a 5th instar larva was removed from its case it first built a sand grain case followed by a leaf panel case. The animal cut panels from the leaf with its mandibles and then further shaped them by chewing round the edge. Just prior to pupation, the case was modified by the attachment of further panels to the anterior; these included panels which for the first time in the life of the larva were arranged with their long axes along the case.  相似文献   

2.
Heterogeneity of big-big hPRL in hyperprolactinemia   总被引:1,自引:0,他引:1  
Sera from a patient with macroprolactinoma (case 1) and from a hyperprolactinemic woman with regular menstruation (case 2) were analyzed for prolactin activity by gel filtration using Sephadex G-100, Sephadex G-200 and TSK G3000SW columns. The chromatographic profile by Sephadex G-100 showed that the percentage of immunoreactive big-big hPRL was 10.7% in case 1 and 64.1% in case 2. On Sephadex G-200 and TSK G3000SW columns, the molecular weight of big-big hPRL was estimated to be more than 500,000 daltons (big-big1 hPRL) in case 1 and approximately 250,000-300,000 daltons (big-big2 hPRL) in case 2. Big-big1 hPRL in case 1 was converted to big and little hPRLs when the serum was treated with 2-mercaptoethanol (2-ME), but part of the big-big2 hPRL in case 2 was converted to a larger molecule. Radioactive big-big hPRL generated by mixing labeled hPRL with the serum from case 1 was eluted with the void volume on Sephadex G-100 column and was not converted to the other molecular forms after 2-ME treatment. There were two radioactive big-big hPRL on TSK G3000SW column and these estimated molecular weights were more than 300,000 daltons. The data demonstrated the existence of at least two forms of big-big hPRL in the serum and indicated that radioactive big-big hPRL may be different from these hPRLs in the serum.  相似文献   

3.
Studies were carried out on the metabolism of lipid peroxides and antioxidative enzymes during diabetes and diabetes superimposed with myocardial infarction. Diabetes was induced using alloxan and myocardial infarction was induced by isoproterenol. In the case of diabetic animals there was a decrease in the levels of lipid peroxides in the heart while in the case of diabetes associated with myocardial infarction it was slightly elevated. The activity of superoxide dismutase and catalase showed a decrease in both the groups. Glutathione showed a fall in the case of diabetes and diabetes associated with myocardial infarction while taurine in heart and ceruloplasmin in the serum was elevated. Histopathological changes in the heart tissue showed some focal changes in the case of both diabetes and diabetes associated with myocardial infarction, but the degree of necrosis was much less than in the case of myocardial infarction.  相似文献   

4.
In this paper a general deterministic discrete-time metapopulation model with a finite number of habitat patches is analysed within the framework of adaptive dynamics. We study a general model and prove analytically that (i) if the resident populations state is a fixed point, then the resident strategy with no migration is an evolutionarily stable strategy, (ii) a mutant population with no migration can invade any resident population in a fixed point state, (iii) in the uniform migration case the strategy not to migrate is attractive under small mutational steps so that selection favours low migration. Some of these results have been previously observed in simulations, but here they are proved analytically in a general case. If the resident population is in a two-cyclic orbit, then the situation is different. In the uniform migration case the invasion behaviour depends both on the type of the residents attractor and the survival probability during migration. If the survival probability during migration is low, then the system evolves towards low migration. If the survival probability is high enough, then evolutionary branching can happen and the system evolves to a situation with several coexisting types. In the case of out-of-phase attractor, evolutionary branching can happen with significantly lower survival probabilities than in the in-phase attractor case. Most results in the two-cyclic case are obtained by numerical simulations. Also, when migration is not uniform we observe in numerical simulations in the two-cyclic orbit case selection for low migration or evolutionary branching depending on the survival probability during migration.  相似文献   

5.
Theoretical basis and favourable therapeutical application of magnetic field in case of trophic ulcerations of the lower limbs are discussed. As a clinical example of such action a case of a 39-year old female patient with trophic ulceration of the leg is presented. Practical advantages of magnetotherapy in similar to the described case patients are suggested.  相似文献   

6.
Summary In case–control research where there are multiple case groups, standard analyses fail to make use of all available information. Multiple events case–control (MECC) studies provide a new approach to sampling from a cohort and are useful when it is desired to study multiple types of events in the cohort. In this design, subjects in the cohort who develop any event of interest are sampled, as well as a fraction of the remaining subjects. We show that a simple case–control analysis of data arising from MECC studies is biased and develop three general estimating‐equation‐based approaches to analyzing data from these studies. We conduct simulation studies to compare the efficiency of the various MECC analyses with each other and with the corresponding conventional analyses. It is shown that the gain in efficiency by using the new design is substantial in many situations. We demonstrate the application of our approach to a nested case–control study of the effect of oral sodium phosphate use on chronic kidney injury with multiple case definitions.  相似文献   

7.
We report a case of chimpanzee trisomy 22 in a captive-born female. Because chromosome 22 in great apes is homologous to human chromosome 21, the present case is analogous to human trisomy 21, also called Down syndrome. The chimpanzee in the present case experienced retarded growth; infantile cataract and vision problems, including nystagmus, strabismus, and keratoconus; congenital atrial septal defect; and hypodontia. All of these symptoms are common in human Down syndrome. This case was the second reported case of trisomy 22 in the chimpanzee. The chimpanzee in our case became blind by 7 years old, making social life with other chimpanzees difficult, but opportunities to interact with other conspecific individuals have been offered routinely. We believe that providing her with the best care over the course of her life will be essential.  相似文献   

8.
Scott Grimm 《Morphology》2011,21(3-4):515-544
This paper presents a framework which connects case assignment with the semantics of argument realization. Broad notions of agency and affectedness are decomposed into more fine-grained semantic properties, loosely based on Dowty??s Proto-Role theory, but conceived in terms of privative opposition and organized into a lattice. This lattice provides a semantic space of participant properties and supports defining hierarchical relations among participant types, interpreted as semantic prominence, as well as topological relations such as ??closeness??, interpreted as semantic similarity between participant types. Cases are defined as connected regions of this space, relating a given case to a structured set of semantic properties. A case system is represented as a semantic system, which embodies oppositions and contrasts, and operates against the backdrop of the general semantics of argument realization, where one can define notions such as maximal agents and maximal patients and represent generalizations from the research on transitivity. Core case markers (e.g. ergative, accusative) are represented as subspaces of the lattice spreading outwards from the maximal agent and maximal patient nodes of the lattice. Case alternations arise when the subspace of the lattice delimited by a predicate??s entailments for an argument is partitioned by different cases, exemplified with the genitive/accusative alternation in Russian occurring with direct objects of certain intensional predicates. This method also provides a treatment of case polysemy, viz. a single case subsuming multiple uses, by relating the diverse uses at the more abstract semantic level of the case??s region on the lattice, demonstrated with non-canonical uses of the dative.  相似文献   

9.
In the analysis of two-period crossover designs, one frequently must consider the case of a categorical response with binary as a special case. These circumstances are considered in this paper and the proposed method—an extension of GART'S tests for the binary case—is similar to that of PIKE, CASAGRANDE and SMITH for the analysis of pair-matched case-control studies. The results are illustrated with a numerical example.  相似文献   

10.
The [2 + 2] cycloaddition of chlorosulfonyl isocyanate to (Z)-4-O-propenyl ethers 16, 17, 29 and 30 proceeds with an excellent stereoselectivity in the case of ether 16 and with moderate stereoselectivity in remaining cases. Adducts were transformed into corresponding oxacephams: 37 in the first case, a mixture of 37/40 in the second and third case, and a mixture of 50/51 in the last case. In all instances addition to the si-re side of the olefin dominates. Oxacephams 41 and 52 with opposite R-configuration at the bridgehead carbon C-5a can be obtained by the alternate methodology based on the alkylation of nitrogen in 4-vinyloxyazetidin-2-one by protected 6-O-triflate 24 or 25, followed by cyclization via intramolecular displacement of the vinyloxy group. Compounds 37, 40, 41, 50, 51 and 52 constitute a convenient entry leading to polyfunctionalized oxacephams.  相似文献   

11.
The effect of dispersal and inbreeding on the evolution of seed dormancy to avoid sib competition is theoretically investigated, using a model which assumes a plant population with patchy spatial structure in a constant environment. Applying the inclusive fitness method, the evolutionarily stable dormancy rates are analytically derived for three cases: (a) an asexual haploid population, (b) a diploid-hermaphrodite population in which the dormancy rate is controlled by seeds, and (c) a diploid-hermaphrodite population in which the dormancy rate is controlled by mother plants. The evolutionarily stable dormancy rates decrease in the order of case (c), case (a), and case (b). In all the cases, the evolutionarily stable dormancy rates increase with decreasing the dispersal rate. Although inbreeding generally increases the evolutionarily stable dormancy rates, inbreeding due to selfing reduces the rate exceptionally in case (c).  相似文献   

12.

Background

The findings of a prevalence survey conducted in western Kenya, in a population with 14.9% HIV prevalence suggested inadequate case finding. We found a high burden of infectious and largely undiagnosed pulmonary tuberculosis (PTB), that a quarter of the prevalent cases had not yet sought care, and a low case detection rate.

Objective and methods

We aimed to identify factors associated with inadequate case finding among adults with PTB in this population by comparing characteristics of 194 PTB patients diagnosed in a health facility after self-report, i.e., through passive case detection, with 88 patients identified through active case detection during the prevalence survey. We examined associations between method of case detection and patient characteristics, including HIV-status, socio-demographic variables and disease severity in univariable and multivariable logistic regression analyses.

Findings

HIV-infection was associated with faster passive case detection in univariable analysis (crude OR 3.5, 95% confidence interval (CI) 2.0–5.9), but in multivariable logistic regression this was largely explained by the presence of cough, illness and clinically diagnosed smear-negative TB (adjusted OR (aOR) HIV 1.8, 95% CI 0.85–3.7). Among the HIV-uninfected passive case detection was less successful in older patients aOR 0.76, 95%CI 0.60–0.97 per 10 years increase), and women (aOR 0.27, 95%CI 0.10–0.73). Reported current or past alcohol use reduced passive case detection in both groups (0.42, 95% CI 0.23–0.79). Among smear-positive patients median durations of cough were 4.0 and 6.9 months in HIV-infected and uninfected patients, respectively.

Conclusion

HIV-uninfected patients with infectious TB who were older, female, relatively less ill, or had a cough of a shorter duration were less likely found through passive case detection. In addition to intensified case finding in HIV-infected persons, increasing the suspicion of TB among HIV-uninfected women and the elderly are needed to improve TB case detection in Kenya.  相似文献   

13.
Mechanical circulatory support (MCS) devices are blood pumps that support or replace the function of the native heart. It is important to minimize the material stresses in the flexing blood sac or diaphragm in order to increase the duration of support these devices can provide. An axisymmetric finite element model of a pusherplate blood pump was constructed to evaluate the effect of various design parameters on the material stresses in a segmented poly(ether polyurethane urea) seamless blood sac. The design parameters of interest were the sac thickness, pump case wall taper, and radius of the sac between the pusherplate and pump case wall. The analysis involved a quasi-static analysis of the systolic ejection phase of the pump. The finite element solution suggested that the principal stresses and strains increased almost linearly with sac thickness. The pump case wall taper had the largest effect; decreasing the peak principal stresses by approximately 35% when the pump case was straight versus tapered. Lastly, the model demonstrated that the radius of the blood sac between the pusherplate and pump case wall had little or no effect on the magnitude of the blood sac stresses. Therefore, this study suggests that in order to minimize the stresses in a blood sac of a pusherplate blood pump, a straight pump case should be chosen with the thinnest sac.  相似文献   

14.
Four patients with common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma are presented. The subclasses of monoclonal protein were IgD kappa (1 case), IgA lambda (1 case), and IgA kappa (2 cases). Bence Jones proteinuria was seen in all cases. The clinical stages were determined as IIA (2 cases) and IIIA (2 cases). All patients died with a median survival time after diagnosis of 62 days due to rapid development of renal failure (3 cases), and renal insufficiency and pneumonia (1 case). According to light microscopic evaluation, these myelomas corresponded to plasmablastic (1 case), immature (2 cases), and intermediate (1 case) types. Both CALLA and a cytoplasmic immunoglobulin identical with the serum monoclonal protein were simultaneously detected in single cells from all cases using immunofluorescent double labeling. These findings suggest that CALLA-positive and plasma-blastic myelomas constitute clinically a subgroup characterized by extremely poor survival but they represent cytologically different subcategories.  相似文献   

15.
探讨应用电子阴道镜在寻找妊娠期阴道出血原因方面的价值。方法:对我院2004年5月-2006年11月64例非产科原因孕期阴道流血的孕妇,进行电子阴道镜检查及颈管分泌物培养和镜下定位活检。结果:阴道镜下发现宫颈赘生物12例,其中2例坏死,10例明显充血水肿;宫颈炎伴活动性出血2例,宫颈炎无活动性出血18例;正常宫颈16例;宫颈上皮内瘤样病变图象15例;宫颈分泌物培养阳性23例。结论:妊娠期不规则阴道出血原因复杂,阴道镜检查能较快排除与查明宫颈及阴道病变所导致的出血。  相似文献   

16.
BACKGROUND: Plasmacytoma of the bladder is an extremely rare tumor, with all information concerning this neoplasm derived from case reports. It can be a major diagnostic pitfall on both histology and urine cytology. CASE: A 95-year-old woman presented with gross hematuria and a large bladder mass detected by ultrasound. The case was initially misdiagnosed as a high grade urothelial carcinoma. Since the urine cytology did not show the classical cytologic features of urothelial carcinoma, the histologic sections were reviewed and immunohistochemical staining performed. The final diagnosis was plasmacytoma of the bladder. Subsequently the patient underwent a skeletal survey and bone scan, which did not reveal any lesion suspicious for multiple myeloma. The patient was scheduled for radiotherapy. CONCLUSION: In this case of bladder plasmacytoma, urine cytology provided a clue to the diagnosis. Urine cytology can be a diagnostic tool to help make this diagnosis in the case of poorly differentiated bladder neoplasm, especially in a patient with a known history of multiple myeloma.  相似文献   

17.
We describe a hemoglobin beta-chain mutant detected incidentally in an unusual profile of glycated hemoglobin (HbA1c) measured by ion-exchange HPLC. Analysis of intact globin by electrospray ionization mass spectrometry (ESI-MS) and peptide analysis by on-line HPLC-ESI-MS-MS revealed the substitution, [beta111(G13)Val-->Ala], which was confirmed by DNA analysis. This was the second case of Hb Stanmore. As the first case combined beta(0)-thalassemia, and the family study in that case showed no case of Hb Stanmore without combined thalassemia, the case presented here is the first case of single heterozygote, and the first Japanese case. Hb Stanmore is isoelectrophoretically silent with only mild clinical symptoms, although stability by isopropanol test was positive.  相似文献   

18.
Despite the fact that migration occurs in a wide variety of taxa worldwide, little is known about the conditions under which migration is expected to evolve from an ancestral resident population. We develop a model that focuses on ecological factors affecting the evolution of migration in a seasonal environment within a genetically explicit framework. We model the evolution of migration for two common types of migration: ‘shared breeding where migrants share a breeding ground with residents and migrate to a separate non-breeding area, versus ‘shared non-breeding’, where migrants share a non-breeding ground with residents and migrate to a separate breeding area. Ecologically, migration is more easily established in the shared-breeding case versus the shared-non-breeding case. Genetically, the additive effect of a migratory allele affects its establishment more in the shared-non-breeding case versus the shared-breeding case, whereas the dominance effect of the allele affects its establishment more in the shared-breeding case versus the shared-non-breeding case. Generally, migratory alleles can invade even when residents are competitively superior to migrants during the shared season. Partial migration occurs when the population is polymorphic for migratory and non-migratory alleles, and is dependent upon which season is shared and the additive and dominance behaviour of the migratory allele.  相似文献   

19.
目的:通过描述2010年北京市手足口病死亡病例的流行病学特点和临床特点,分析手足口病重症病例发生死亡的危险因素,为防制手足口病,减少手足口病的死亡提供科学依据。方法:采用现况描述及病例对照研究的方法,对2010年北京市手足口病死亡病例的特点进行分析。结果:2010年北京市共报告18例手足口病死亡病例,88.9%分布在5.8月份;死亡病例的男女比例为3.5:1;年龄均小于4岁;流动人口聚集区的死亡病例较多;散居儿童及外地户籍儿童比例高,分别为83.3%和94.4%。死亡病例均出现出疹、发热及神经精神系统症状,整体精神状况,呼吸功能指标以及循环系统受累明显。与重症痊愈病例相比,感染EV71型病毒是发生死亡的危险因素(x2=4.774,P=0.029)。结论:手足口病死亡病例分布与重症病例分布基本一致。应对流动人口聚集地区的4岁以下婴幼儿重症病例进行重点防控。  相似文献   

20.
BackgroundA better understanding of case management practices is required to improve inpatient pediatric care in resource-limited settings. Here we utilize data from a unique health facility-based surveillance system at six Ugandan hospitals to evaluate the quality of pediatric case management and the factors associated with appropriate care.MethodsAll children up to the age of 14 years admitted to six district or regional hospitals over 15 months were included in the study. Four case management categories were defined for analysis: suspected malaria, selected illnesses requiring antibiotics, suspected anemia, and diarrhea. The quality of case management for each category was determined by comparing recorded treatments with evidence-based best practices as defined in national guidelines. Associations between variables of interest and the receipt of appropriate case management were estimated using multivariable logistic regression.ResultsA total of 30,351 admissions were screened for inclusion in the analysis. Ninety-two percent of children met criteria for suspected malaria and 81% received appropriate case management. Thirty-two percent of children had selected illnesses requiring antibiotics and 89% received appropriate antibiotics. Thirty percent of children met criteria for suspected anemia and 38% received appropriate case management. Twelve percent of children had diarrhea and 18% received appropriate case management. Multivariable logistic regression revealed large differences in the quality of care between health facilities. There was also a strong association between a positive malaria diagnostic test result and the odds of receiving appropriate case management for comorbid non-malarial illnesses - children with a positive malaria test were more likely to receive appropriate care for anemia and less likely for illnesses requiring antibiotics and diarrhea.ConclusionsAppropriate management of suspected anemia and diarrhea occurred infrequently. Pediatric quality improvement initiatives should target deficiencies in care unique to each health facility, and interventions should focus on the simultaneous management of multiple diagnoses.  相似文献   

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