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71.
The present study aims to give detailed histomorphological features of the hippocampus of adult male New Zealand rabbits. Both histological and histochemical specimens were prepared to be examined microscopically by using a light microscope. The hippocampus appeared as C-shaped hippocampal proper, dentate gyrus, and subiculum. The hippocampal proper subdivided along its length according to the density and size of its major constituent pyramidal cells into four distinct regions named Cornu Ammonis (CA1, CA2, CA3, and CA4). With the histochemical preparations, each of these regions consisted of five layers, stratum alveolus, stratum oriens, stratum pyramidale, stratum radiatum, and stratum lacunosum-moleculare. The stratum pyramidale constituted the middle dark zone and contained the principal excitatory neurons and a few interneurons. Histochemically, the pyramidal neurons along all regions of the CA reacted positively to Grimelius silver impregnation, lead hematoxylin, Gomori's aldehyde fuchsin, aldehyde thionine, Gomori's chrome alum hematoxylin, and performic acid alcian blue stains. Immunohistochemically, the pyramidal neurons reacted positively to anti-NSE antibodies. The dentate gyrus was formed of three distinct layers. The subiculum was formed of proper subiculum, presubiculum, and parasubiculum.  相似文献   
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PURPOSE Transanal excision is an appealing treatment for low rectal cancers because of its low morbidity, mortality, and better functional results than transabdominal procedures. However, controversy exists about whether it compromises the potential for cure. Several, recent reports of high recurrence rates after local excision prompted us to review our results of transanal excision alone in patients with T1 rectal cancers.METHODS All patients with T1 low rectal cancer undergoing local excision alone between 1980 through 1998 were reviewed for local recurrence, distant metastasis, disease-free interval, results of salvage surgery, and overall and disease-free survival. Demographics, tumor size, distance from anal verge, and preoperative endoluminal ultrasound results also were recorded. Patients with poorly differentiated tumors, perineural or lymphovascular invasion, or with mucinous component were excluded.RESULTS Fifty-two patients underwent transanal excision during the study period. Five-year recurrence was estimated to be 29.38 percent (95 percent confidence interval, 15.39–43.48). For 52 patients, five-year, cancer-specific and overall survival rates were 89 and 75 percent respectively. Fourteen of 15 patients with recurrence underwent salvage treatment with 56.2 percent (95 percent confidence interval, 35.2–90) five-year survival rate. Gender, preoperative staging by endorectal ultrasound, distance from the anal verge, tumor size, location, and T1 status discovered after transanal excision of a villous adenoma did not influence local recurrence or tumor-specific survival.CONCLUSIONS Transanal excision for T1 rectal tumors with low-grade malignancy has a high rate of recurrence. Although overall cancer survival rates might be regarded as satisfactory, this high recurrence and low salvage rate raises the issue about the role of transanal excision alone for early rectal cancer and the possible need for adjuvant therapy or increased role of resective surgery.Presented at the meeting of The American Society of Colon and Rectal Surgeons, Chicago, Illinois, June 3 to 7, 2002.  相似文献   
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Starfish can regenerate entire arms following their loss by both autotomic and traumatic amputation. Although the overall regenerative process has been studied several times in different asteroid species, there is still a considerable gap of knowledge as far as the detailed aspects of the repair phase at tissue and cellular level are concerned, particularly in post‐traumatic regeneration. The present work is focused on the arm regeneration model in the Mediterranean red starfish Echinaster sepositus; to describe the early cellular mechanisms of arm regeneration following traumatic amputation, different microscopy techniques were employed. In E. sepositus, the repair phase was characterized by prompt wound healing by a syncytial network of phagocytes and re‐epithelialisation followed by a localized subepidermal oedematous area formation. Scattered and apparently undifferentiated cells, intermixed with numerous phagocytes, were frequently found in the wound area during these first stages of regeneration and extensive dedifferentiation phenomena were seen at the level of the stump, particularly in the muscle bundles. A true localized blastema did not form. Our results confirm that regeneration in asteroids mainly relies on morphallactic processes, consisting in extensive rearrangement of the existing tissues which contribute to the new tissues through cell dedifferentiation, redifferentiation, and/or migration.  相似文献   
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Objectives:

To assess health care services provided to type 1 and type 2 diabetic patients and diabetes health care expenditure in the Kingdom of Saudi Arabia (KSA).

Methods:

This study was part of a nationwide, household, population based cross-sectional survey conducted at the University Diabetes Center, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia between January 2007 and December 2009 covering 13 administrative regions of the Kingdom. Using patients’ interview questionnaires, health care services data were collected by trained staff.

Results:

A total of 5,983 diabetic patients were chosen to assess health care services and expenditure. Approximately 92.2% of health services were governmental and the remaining 7.8% were in private services. The mean annual number of visits to physicians was 6.5±3.9 and laboratories was 5.1±3.9. Diabetic patients required one admission every 3 years with a mean admission duration of 13.3±28.3 days. General practitioners managed 85.9% of diabetic cases alone, or shared with internists and/or endocrinologists. Health care expenditure was governmental in 90% of cases, while it was personal in 7.7% or based on insurance payment in 2.3%.

Conclusion:

Health services and its expenditure provided to diabetic citizens in Saudi Arabia are mainly governmental. Empowerment of the role of both the private sector and health insurance system is badly needed, aside from implementing proper management guidelines to deliver good services at different levels.The health care system (HCS) in the Kingdom of Saudi Arabia (KSA) is growing at an annual rate of 2% to meet the increasing demand for health care services caused by increased population growth, and a surge in chronic non-communicable diseases.1 This has resulted in an increase in the total health care budget by more than 2 times; from 30 billion Saudi Riyals (SR) (US$8 billion) in 2008 to approximately SR69 billion (US$18.4 billion US dollars) in the year 2011 with a cumulative allocation of SR113 billion (U$30.13 billion) in 2010 and 2011; which accounted for 3.7% of the estimated country’s gross domestic product (GDP), which is one of the highest among Gulf Cooperation Council (GCC) countries.2 The Saudi health care system, which is ranked 26th among 190 countries by the World Health Organization (WHO),3 has a lower percentage of average expenditure in relation to the country’s GDP than many developed and developing countries.4 The government HCS in KSA is structured to deliver free health care services to Saudi citizens through various public hospitals and primary health care centers (PHCCs) including government health sectors, such as the Ministry of Health (MOH), Military Health Services and University Health Institutions. In addition to this, the private health care sector, through its clinics and hospitals, provided 31.1% of the total health care services in KSA in 2013.5 The real challenge facing the Kingdom’s HSC is the increased demands for hospital beds and medical personnel to meet international standards.6 The population ratio of physician and nurses in the Kingdom is lower than the global ratio being 9.4 physicians and 21 nurses per 10,000 of population versus 13 physicians and 28 nurses globally.7 This explains the current imbalance between the growth in HCS and the real medical needs of Saudi citizens.Diabetes mellitus, being the most prevalent chronic non-communicable disease in the Kingdom, has a significant effect on the country’s HCS and overall economy.8,9 This is proved by the fact that 25.4% of Saudi citizens older than 30 years of age have diabetes, which implies that there are approximately 1.5 million Saudi citizens suffering from this chronic disease.10 This is aside from the fact that more than 70% of known diabetic patients in the Middle Eastern countries have poorly controlled diabetes,11 associated with high rates of chronic complications that place greater pressure on health services and expenditure, where in 2013, it was estimated that the Middle East and North Africa (MENA) region spent US$13.6 billion on diabetes care with the spending per person with diabetes, where the spending in Saudi Arabia was US$934, which is far below other GCC such as United Arab Emirates (US$2,228), Qatar (US$2,199), and Kuwait (US$1,886),12 although we strongly believe that these figures are underestimated.Diabetic patients are currently managed at all health care levels, from primary to secondary and tertiary levels by general practitioners (GPs), internists, and endocrinologists.13 Since diabetes care involves many medical disciplines, such as ophthalmology, cardiology, nephrology and so forth, specialized diabetes clinics, and diabetes centers are needed to function as liaising bodies. Although health care needs for diabetic patients’ management at a global level have witnessed a clear shift to the primary from secondary and tertiary health care levels,14 diabetic patients in the Kingdom are still receiving services at secondary or even tertiary levels. Since there are no studies so far that have looked into the health care services provided to diabetic patients in KSA, the current study, as a part of the Saudi Abnormal Glucose Metabolism and Diabetes Impact (SAUDI-DM) survey,10 has investigated the current status of health care services provided to diabetic patients. This study aimed to assess the medical system providing care to diabetic patients, and methods of payment through a randomly selected cohort of diabetic patients at a country level.  相似文献   
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