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91.
Sporozoites and free circumsporozoite (CS) protein were stained immunoenzymatically in 1-min saliva samples collected fromAnopheles stephensi mosquitoes infected with eitherPlasmodium berghei orP. falciparum. The number of sporozoites in 1-min saliva-streak samples significantly increased as the salivary gland index rose from 3+ to 4+. ForP. berghei-infected mosquitoes from which saliva had been collected before 30 days postfeed, the median sporozoite counts for 3+ and 4+ gland indexes were 4.5 and 116, respectively. ForP. falciparum-infected mosquitoes, the median counts obtained in two experiments were 4.5 and 14.5 (3+) and 97 and 107 (4+), respectively. The frequency of sporozoite detection in the saliva of mosquitoes containing <100 salivary-gland sporozoites was low (0.1), whereas that in the saliva of mosquitoes with >100 sporozoites was high (0.96). In highly infected 4+P. berghei-infected mosquitoes from which saliva had been collected after 30 days postinfection, both the volume of saliva collected and the median number of sporozoites recovered decreased significantly. 相似文献
92.
Summary
The compartment syndrome (cs) is characterized by an increased tissue pressure in a limited space. Pathophysiologically, it
is a multifactorial disease that is potentially induced by an initial trauma and develops according to the existence of cofactors.
Cofactors are, for instance, the circulation of the patient and the initial treatment of the impending cs. In particular,
the microcirculation is altered with endothelial destruction, development of a capillary leak, protein loss from intravasal
space and the development of an interstitial and intracellular third space. An impaired drainage of the lymphatic and venous
system causes a venous infarction. An arterial infarction results if the tissue pressure exceeds the arteriolar pressure.
An accompanying ischemia reperfusion mechanism increases the trauma load. In disadvantageous cases, the patients are in danger
of developing a multi-organ deficiency syndrome (MODS) by an uncontrolled inflammatory reaction, by intravasal volume loss
and by a myonephropathic systemic reaction. Clinically, the patients suffer a disproportionate amount of pain, followed by
neurological signs. Especially in noncompliant patients, tissue pressure measurement is useful. Resuscitation of the circulation
as well as splitting of casts is important. In case of a manifest cs, dermatofasciotomy has to be performed as an emergency
operation. Even if cs is diagnosed early and fasciotomy is carried out early, the development of sequellae cannot be avoided
in every single case.
相似文献
93.
African Americans experienced massive internal migrations that shifted more than 6 million Southern-born blacks to other sections of the United States over the past century, a trend that only recently has been reversed. Whenever mass migration takes place, there is an opportunity to examine the role of the native and relocated environments in the development of disease. This article examines those relationships for diabetes mellitus, a group of diseases that disproportionately affect African-Americans relative to other racial and ethnic groups in the United States. Age-specific and age-adjusted rates with 95% confidence intervals were calculated for males and females for combinations of five regions of birth and four regions of residence at time of death. Southern-born males had statistically significantly higher death rates from diabetes than did their counterparts who died in the same regions in 9 of 16 comparisons. For females, those born in the South had statistically significantly higher rates in 15 of 16 comparisons. The results of this study indicate that place of birth and early life experiences are statistically associated with diabetes mortality among African Americans regardless of place of residence at time of death. 相似文献
94.
Routine clinical use of radiographic contrast media (RCM) causes adverse reactions in some patients. To elucidate the mechanisms of these reactions both in vitro and in vivo studies are necessary. In this study, RCM-induced histamine release from isolated mast cells was compared with the in vivo release of histamine and cardiovascular symptoms using a porcine model. The 2 non-ionic preparations examined (Solutrast and Ultravist) released little or no histamine from the 4 cell types tested (porcine pulmonary, cardiac, hepatic, and renal mast cells). The 4 ionic preparations (Angiographin, Hexabrix Rayvist, and Telebrix) caused histamine release from most of the cell suspensions. In almost all cases, the cardiac mast cells were the most sensitive followed by the hepatic mast cells. All 4 RCM tested in vivo produced elevated plasma histamine levels in some animals. The highest incidence was observed using the ionic, high osmolal Rayvist (6 of 12 animals), followed by the non-ionic RCM with the lowest osmolality Ultravist (4 of 12 animals). In vivo, mechanisms in addition to direct histamine release may also be involved in RCM-induced adverse reactions, since low osmolal, non-ionic RCM can cause elevated plasma histamine levels without in vitro release. The susceptibility of cardiac mast cells to RCM-induced histamine release suggests that patients undergoing e.g. coronary angiography may be especially at risk for an adverse reaction. 相似文献
95.
J Schneider M Meier D Maroske H Kaffarnik 《Clinica chimica acta; international journal of clinical chemistry》1988,171(2-3):305-310
In spite of significant advances in the past decade, assessing of severe prognosis in acute pancreatitis remains an improvable problem. Actually the standardized means are clinical, multiple laboratory and peritoneal lavage. In a series of 20 subsequent cases of acute pancreatitis with a lethality of 30%, apolipoprotein AII has proven to be a predictor of fatal outcome with a sensitivity in the range of all other methods together. Competitive replacement of Apo AII by serum amyloid like substance A as an indicator for the amount of necrosis would explain this relation. Whether this suggestion can be confirmed by ongoing work or not, apolipoprotein AII merits attention in this context. 相似文献
96.
97.
Kirk J. Schneider 《Clinical psychology》2002,9(1):26-27
I contend that although the Luborsky et al. findings on the Dodo bird verdict are noteworthy, the methodology on which they are based is significantly delimited. Amplifying Luborsky et al.'s moderate recognition of that delimitation, I propose a qualitative complement to the extant research. I call this complement "amalgamated" qualitative research and propose that it will deepen, clarify, and contextualize Luborsky et al.'s enigmatic findings. Until this amalgam is implemented, therapy research will be relegated to impressions rather than fine-grained illuminations. 相似文献
98.
Different proliferative activity of the glandular and myoepithelial lineages in benign proliferative and early malignant breast diseases. 总被引:3,自引:0,他引:3
Agnes Bánkfalvi Andreas Ludwig Bettina De-Hesselle Horst Buerger Igor B Buchwalow Werner Boecker 《Modern pathology》2004,17(9):1051-1061
The aim of the present study was to explore cell biological characteristics of normal breast, benign proliferative breast diseases and noninvasive breast malignancies based on the recently published adult progenitor cell concept from our group. Here, we investigated the proliferative activity of CK5/14(+), CK8/18/19(+) and alpha-smooth muscle actin(+) cellular phenotypes encountered in normal mammary gland, in a series of usual ductal hyperplasias and early malignant breast diseases, such as atypical ductal and lobular hyperplasias, as well as ductal and lobular in situ carcinomas. Immunohistochemical double labeling was performed on frozen sections from diagnostic breast biopsies by using antibodies to basal cytokeratins (CK5/14), glandular cytokeratins (CK8/18/19), smooth muscle actin and the Ki-67 antigen (MIB1). Normal breast tissues and usual ductal hyperplasias were characterized by a heterogeneous cellular composition of the growth fraction. The proliferative cell compartment consisted of CK8/18/19(+) glandular and, in a variable proportion, CK5/14(+) progenitor phenotypes. In contrast, noninvasive breast malignancies were composed of a monotonous proliferation of CK 8/18/19(+) neoplastic glandular cells. These findings indicate a significant role of progenitor cells in the development of benign proliferative breast diseases and lend support to the view that malignant transformation in the human breast usually occurs in a cell committed to the glandular lineage. Our results provide cell kinetic support to the functional progenitor cell hypothesis, and we propose this concept as an operative model for understanding benign proliferative and malignant breast diseases. 相似文献
99.
In a retrospective study, 1.173 fractures of the proximal femur, which had been treated surgically, were analysed in two periods from 1975 to 1991 and from 1992 to 2000. The influence on mortality of preoperative risk factors and primary treatment with total hip replacement (THR), even in cases of pertrochanteric fractures, was analysed by stepwise logistic regression. In the later period, mortality within 90 days was 13.1%, and within 1 year 22.2%. Rejection of hemiendoprosthesis in high-risk patients with intracapsular fractures increased the mortality rate from 6.3% to 11.8%. The introduction of dynamic hip screws instead of Ender nails led to a reduction of mortality from 16.5 to 7.1%. Higher mortality after THR (27.6%) compared to osteosynthesis (15.5%) in pertrochanteric femur and lateral neck fractures was due to higher age and increased risk factors. Although the influence of some risk factors could be reduced, age, sex and morbidity influenced the outcome more than surgical treatment. THP, even after pertrochanteric fractures, is reasonable if it guarantees a quick and enduring mobilisation of the patient. Bicentric bipolar prostheses are recommended for high risk patients. 相似文献
100.
GM1 ganglioside is believed to be important in promoting the recovery of neurons from injury. The present study assesses the ability of GM1 to repair or prevent the damage of dopamine neurons caused by the neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Treatment of mesencephalic cell cultures with 2.5 μM MPP+ resulted in the loss of 30% of tyrosine hydoxylase (TH) immunoreactive neurons. In contrast, cultures administered 100 μM GM1 ganglioside for 3 days after toxin treatment contained nearly control numbers of TH+ neurons (97%). This reparative effect of GM1 was reflected in parallel increases in TH enzyme activity, dopamine and dopac levels. Cultures sustaining greater insult from higher doses of MPP+ (5.0–10.0 μM) did not benefit from ganglioside treatment, suggesting that rescue by GM1 depended on the degree of initial damage to cells. Moreover, the timing of ganglioside treatment was critical; pretreatment with GM1 alone did not prevent or attenuate the damage caused by subsequent incubation in 2.5 μM MPP+. 相似文献