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161.
We aimed to observe morphological changes in the spleen from the emergence of the primordium to the end of the embryonic period using histological serial sections of 228 samples. Between Carnegie stages (CSs) 14 and 17, the spleen was usually recognized as a bulge in the dorsal mesogastrium (DM), and after CS 20, the spleen became apparent. Intrasplenic folds were observed later. A high‐density area was first recognized in 6 of the 58 cases at CS 16 and in all cases examined after CS 18. The spleen was recognized neither as a bulge nor as a high‐density area at CS 13. The mesothelium was pseudostratified until CS 16 and was replaced with high columnar cells and then with low columnar cells. The basement membrane was obvious after CS 17. The mesenchymal cells differentiated from cells in the DM, and sinus formation started at CS 20. Hematopoietic cells were detected after CS 18. The vessels were observed at CS 14 in the DM. Hilus formation was observed after CS 20. The parallel entries of the arteries and veins were observed at CS 23. The rate of increase in spleen length in relation to that of stomach length along the cranial‐caudal direction was 0.51 ± 0.11, which remained constant during CSs 19 and 23, indicating that their growths were similar. These data may help to better understand the development of normal human embryos and to detect abnormal embryos in the early stages of development. Anat Rec, 298:820–826, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
162.
Fractures of the distal radius in children have a similar incidence to that found in postmenopausal women but occur more commonly in boys than in girls. Fractures of the distal tibia are uncommon in children and show no sex specificity. About 90% of lengthening of the radius but only 30% of lengthening of the tibia during puberty occur at the distal growth plate. We speculated that more rapid modeling at the distal radial metaphysis results in a greater dissociation between growth and mineral accrual than observed at the distal tibia. We measured the macro‐ and microarchitecture of the distal radial and tibial metaphysis using high‐resolution peripheral quantitative computed tomography in a cross‐sectional study of 69 healthy boys and 60 healthy girls aged from 5 to 18 years. Bone diameters were larger but total volumetric bone mineral density (vBMD) was lower at the distal radius (not at the distal tibia) by 20% in boys and by 15% in girls at Tanner stage III than in children of the same sex at Tanner stage I (both p < .05). In boys at Tanner stage III, total vBMD was lower because the larger radial total cross‐sectional area (CSA) had a thinner cortex with lower vBMD than in boys at Tanner stage I. In girls at Tanner stage III, the larger total radial CSA was not associated with a difference in cortical thickness or cortical vBMD relative to girls in Tanner stage I. Cortical thickness and density at both sites in both sexes after Tanner stage III were greater than in younger children. Trabecular bone volume fraction (BV/TV) was higher in boys than in girls at both sites and more so after puberty because trabeculae were thicker in more mature boys but not in girls. There was no sex‐ or age‐related differences in trabecular number at either site. We infer that longitudinal growth outpaces mineral accrual in both sexes at the distal radius, where bone grows rapidly. The dissociation produces transitory low cortical thickness and vBMD in boys but not in girls. These structural features in part may account for the site and sex specificity of metaphyseal fractures during growth. © 2010 American Society for Bone and Mineral Research  相似文献   
163.
Nasal endotracheal intubation using GlideScope   总被引:1,自引:0,他引:1  
We describe the performance of GlideScope in 34 consecutive patients who required nasal endotracheal intubation for surgical convenience. In the 34 patients, nasal endotracheal intubation was achieved in 52 +/- 22 (mean +/- SD) sec by unexperienced clinicians, and in 50 +/- 17 sec by anesthetists in the department. Margill forceps were not needed for any patient during nasotracheal intubation. The improved coordination afforded by an image on a video monitor seen by both the assistant providing laryngeal manipulation and the anesthetist handling the laryngoscope resulted in a significant advantage over the conventional laryngoscope technique. GlideScope seems to be a novel useful device for nasal endotracheal intubation.  相似文献   
164.

Aims:

To evaluate the prevalence and characteristics of different neurological and psychiatric presentations in patients admitted to hospital with systemic lupus erythematosus (SLE).

Materials and Methods:

In this retrospective hospital-based study, we examined the medical records of patients with SLE who were referred to the hospitals affiliated to Shiraz University of Medical Sciences from 1995 to 2005. All patients of SLE who had clinical neurological or psychiatric features were included in this study. The patients´ demographic data, findings on general examination, neuropsychiatric manifestations, and the results of laboratory investigations and imaging studies were recorded. Clinical manifestations were classified according to the American College of Rheumatology (ACR) case definitions.

Results:

Of the 407 study patients, 11.3% had neuropsychiatric complications. The most frequent findings were seizure (63%), headache (60%), and decreased level of consciousness (50%). Cerebrovascular disease (28.3%), seizure disorder (26.5%), and acute confusional state (19.6%) were the most prevalent syndromes.

Conclusion:

The prevalence and nature of different neurological presentations of SLE in Iranian patients has some similarities to that seen in other populations, as well as some differences. Ethnic and environmental factors may contribute to these differences.  相似文献   
165.
Previous studies have revealed that 5-HT1A agonists ameliorate antipsychotic-induced extrapyramidal symptoms (EPS) through postsynaptic 5-HT1A receptors. Here, we conducted an intracerebral microinjection study of (±)-8-hydroxy-2-(di-n-propylamino)-tetralin ((±)8-OH-DPAT) to determine the action site of the 5-HT1A agonist in alleviating EPS. Bilateral microinjection of(±)8-OH-DPAT (5 µg/1 µL per side) either into the primary motor cortex (MC) or the dorsolateral striatum (dlST) significantly attenuated haloperidol-induced catalepsy in rats. The anticataleptic action of (±)8-OH-DPAT was more prominent with the MC injection than with the dlST injection. WAY-100135 (a selective 5-HT1A antagonist) completely antagonized the reversal of haloperidol-induced catalepsy both by intracortical and intrastriatal (±)8-OH-DPAT. Furthermore, lesioning of dopamine neurons with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (30 mg/kg/day, i.p., for 4 days) did not alter the anti-EPS actions of (±)8-OH-DPAT in a mouse pole test. The present results strongly suggest that 5-HT1A agonist alleviates antipsychotic-induced EPS by activating postsynaptic 5-HT1A receptors in the MC and dlST, probably through non-dopaminergic mechanisms.  相似文献   
166.
One cause of X-linked dilated cardiomyopathies is mutation of the dystrophin gene. We report the case of a young boy who suffered from dilated cardiomyopathy caused only by dystrophin-deficient cardiac muscle, but who did not present with any clinical signs of skeletal myopathy. Sequence analysis of the patient's dystrophin gene revealed the presence of a novel single point mutation at the first exon-intron boundary, inactivating the 5' splice site consensus sequence of the first intron. The lack of muscle weakness observed clinically can be explained by expression of the brain and Purkinje dystrophin isoforms in skeletal muscle.  相似文献   
167.
The aim of this study was to determine whether estrogen modulates central and peripheral responses to cold in female rats. In ovariectomized female rats with and without administered estrogen [E2 (+) and E2 (−), respectively], the counts of cFos-immunoreactive cells in the medial preoptic nucleus (MPO) and dorsomedial hypothalamic nucleus (DMH) in the hypothalamus were greater in the E2 (+) rats than in the E2 (−) rats at 5°C. Examination of the response of normal female rats to exposure to 5°C at different phases of the estrus cycle revealed that counts of cFos-immunoreactive cells in the MPO, DMH, and posterior hypothalamus and the level of uncoupling protein 1 mRNA in the brown adipose tissues were greater in the proestrus phase than on day 1 of the diestrus phase. This result was linked to the level of plasma estrogen. The body temperature during cold exposure was higher in the E2 (+) rats than in the E2 (−) rats and was also higher in the proestrus phase than on day 1 of the diestrus phase. We conclude that estrogen may affect central and peripheral responses involved in thermoregulation in the cold.  相似文献   
168.
Identification of regulatory T cells (Tregs) has led to breaking the dichotomy of the Th1/Th2 axis in the immunopathology of several diseases such as autoimmune diseases and cancer. Despite the presence of extensive information about immunobiology of Tregs in pathogenesis of autoimmune diseases, little is known about the frequency and function of these cells in hematologic malignancies, particularly chronic lymphocytic leukemia (CLL). Recent data have demonstrated increased frequency and intact functional capacity of CD4+ Tregs in CLL patients. However, the precise role of these cells in the immunopathology of CLL is not well known. While targeting Tregs in cancer diseases seems to be an interesting immunotherapeutic approach, such therapeutic interventions in CLL might be deleterious due to suppression of the tumor-specific adaptive and innate immune responses. Thus, the precise biological and regulatory functions of all Tregs subsets should be carefully investigated before planning any immunotherapeutic interventions based on targeting of Tregs. In this communication, we review the recent data published on immunobiology of Tregs in CLL and discuss about the possibility of targeting Tregs in CLL.  相似文献   
169.
BackgroundThe cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene, is one of the candidate genes for susceptibility to Graves' disease. This study aimed to investigate the association of Graves' disease and Graves' ophthalmopathy with polymorphisms at position + 49 in exon 1 and positions ? 318 and ? 1147 in the promoter region of CTLA-4 gene in Iranian patients.MethodsA total of 205 unrelated Iranian patients with Graves' disease who were referred to the outpatient endocrine clinic of a large university general hospital and 103 sex-matched healthy controls were included in this study. Venous blood was obtained, genomic DNA was extracted by a salting out method, and the polymorphisms at positions + 49, ? 318 and ? 1147 of the CTLA-4 gene were determined using the PCR-restriction fragment length polymorphism method (PCR-RFLP). Genotype and allele frequencies were determined.ResultsThe frequency of the G allele at position + 49 was significantly higher in patients with Graves' disease than in the control group (27.1% vs. 15.1%, OR = 2.096, 95%CI = 1.350–3.253 and p < 0.01). Significant trends were not seen for the other two polymorphisms studied. In patients with ophthalmopathy, the frequency of the G allele at position + 49 was higher than in those without ophthalmopathy (33.8% vs. 20.0%, OR = 2.043, 95%CI = 1.304–3.202 and p < 0.01).ConclusionThe results of this study suggest that the G allele at position + 49 in exon1 of the CTLA-4 gene is associated with Graves' disease and Graves' ophthalmopathy in Iranian patients.  相似文献   
170.
OBJECTIVE: Lower socioeconomic status (SES) is associated in industrialized countries with unhealthy lifestyle characteristics, such as smoking, physical inactivity and being overweight or obese. This paper examines changes over time in the association between SES and smoking status, physical activity and being overweight or obese in Australia. METHODS: Data were taken from three successive national health surveys in Australia carried out in 1989-90 (n = 54,576), 1995 (n = 53,828) and 2001 (n = 26,863). Participants in these surveys were selected using a national probability sampling strategy, and aggregated data for geographical areas are used to determine the changing association between SES and lifestyle over time. FINDINGS: Overall, men had less healthy lifestyles. In 2001 inverse SES trends for both men and women showed that those living in lower SES areas were more likely to smoke and to be sedentary and obese. There were some important socioeconomic changes over the period 1989-90 to 2001. The least socioeconomically disadvantaged areas had the largest decrease in the percentage of people smoking tobacco (24% decrease for men and 12% for women) and the largest decrease in the percentage of people reporting sedentary activity levels (25% decrease for men and 22% for women). While there has been a general increase in the percentage over time of those who are overweight or obese, there is a modest trend for being overweight to have increased (by about 16% only among females) among those living in areas of higher SES. CONCLUSION: Socioeconomic inequalities have been increasing for several key risk behaviours related to health; this suggests that specific population-based prevention strategies intended to reduce health inequalities are needed.  相似文献   
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