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61.
Several investigators have estimated the intracranial volume (ICV) in the past which indirectly reflects the brain volume. Most of these studies have been made on the dry skulls using linear dimensions, packing methods or occasionally radiological methods. It is also reported that the etiology of cerebellar tonsillar herniation is closely related to the size of the foramen magnum (FM). In the present study the ICVs have been estimated in 28 dry skulls using filling water method and the surface area of FMs were measured planimetry method. The estimated mean ICV was 1,311 +/- 133 cm. Surface area of FM was 760 +/- 144 mm. Antero-posterior and lateral direct roentgenograms of the skulls were also taken and the width, height and length (WHL) of the skull were measured by means of the cephalometry on radiograms. The relationship between the ICV, WHL and surface area of FM were analyzed statistically. The ICV, WHL and surface area of FM was correlated well (r = 0.271, P < 0.005; r = 0.265, P < 0.005, respectively) and a regression formula was proposed. Our results showed that skulls with larger ICV and WHL have larger FM surface area. We also suggested a regression formula that could be used to predict the surface area of FM regarding to the ICV and WHL values. In the next step, we took roentgenograms of skulls and obtain ICV measuring the width, length and height of skulls by means of cephalometry and investigate the relation between the findings of cephalometry and surface area of FM. The cephalometry could apply on living subjects and, thereby, our findings could provide some data to evaluate the etiology of Arnold Chiari malformation and achondroplasia for living subjects.  相似文献   
62.
Two atypical cases of xeroderma pigmentosum are reported. One of these cases with lung metastasis of squamous cell carcinoma in the first decade of life and the other with late onset disease (XP) in fifth decade of life. Lung metastasis of squamous cell carcinoma in first decade of life in patients with xeroderma pigmentosum has never been reported in the literature to our knowledge. Late onset of the disease in fifth decade is also a rare condition. Clinicians should be more alert for the internal organ metastases to improve the survival of the patients and should never forget that xeroderma pigmentosum has got a wide range of clinical presentation.  相似文献   
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PURPOSE: To assess the effects of exposure to exhaust particles on intima-media thickness of the common carotid artery in highway toll collectors. METHODS: Sixty-one highway toll collectors (HTCs) between 24 and 56 years of age (mean, 36.2 +/- 7.3) and 48 controls between 24 and 64 years of age (mean, 42.6 +/- 10.6) were evaluated with gray-scale sonography to measure intima-media thickness (IMT) of the common carotid artery (CCA). Subgroups were categorized according to duration of exhaust exposure and further divided according to tobacco use. RESULTS: CCA IMT was higher (0.8 +/- 0.2 mm) in HTCs than in the control group (0.6 +/- 0.1 mm; p < 0.001) and remained higher when subgroups with similar smoking habits were compared. In HTCs, IMT was greater when the number of years working in tollbooths was greater (p = 0.023). IMT was lower in HTCs with an exposure duration of < 10 years compared with a duration of 10-20 years (p = 0.017) or > 20 years (p value not significant). CONCLUSION: Air pollution has a widely acknowledged negative effect on humans. This study confirms that exposure to exhaust particles might cause wall thickening of carotid arteries.  相似文献   
64.
The Cavalieri estimator using a point grid is used to estimate the volume of three-dimensional structures based on two-dimensional slices of the object. The size of the components of intracranial neural structures should have proportional relations among them. The volume fraction approach of stereological methods provides information about volumetric relations of the components of structures. The purpose of our study is to estimate the volume and volume fraction data related to the cerebrum, cerebellum and brain stem. In this study, volume of the total brain, cerebrum, cerebellum and brain stem were estimated in 24 young Turkish volunteers (12 males and 12 females) who are free of any neurological symptoms and signs. The volume and volume fraction of the total brain, cerebrum, cerebellum and brain stem were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods. The mean (+/-SD) total brain, cerebrum and cerebellum volumes were 1,202.05 +/- 103.51, 1,143.65 +/- 106.25 cm(3) in males and females, 1,060.0 +/- 94.6, 1,008.9 +/- 104.3 cm(3 )in males and females, 117.75 +/- 10.7, 111.83 +/- 8.0 cm(3) in males and females, respectively. The mean brain stem volumes were 24.3 +/- 2.89, 22.9 +/- 4.49 cm(3) in males and females, respectively. Our results revealed that female subjects have less cerebral, cerebellar and brain stem volumes compared to males, although there was no statistically significant difference between genders (P > 0.05). The volume ratio of the cerebrum to total brain volume (TBV), cerebellum to TBV and brain stem to TBV were 88.16 and 88.13% in males and females, 9.8 and 9.8% in males and females, 2.03 and 2.03% in males and females, respectively. The volume ratio of the cerebellum to cerebrum, brain stem to cerebrum and brain stem to cerebellum were 11.12 and 11.16% in males and females, 2.30 and 2.31% in males and females, 20.7 and 20.6% in males and females, respectively. The difference between the genders was not statistically significant (P > 0.05). Our results revealed that the volumetric composition of the cerebrum, cerebellum and brain stem does not show sexual dimorphism.  相似文献   
65.
Coronary artery dissection is an uncommon but potentially serious complication in percutaneous coronary interventions. We treated a 53-year-old female patient with right coronary spasm, which was misdiagnosed as a coronary lesion. The coronary spasm resolved with nitrate administration, but proximal coronary dissection developed during angiography. It progressed anterograde and led to inferior myocardial infarction and severe hemodynamic instability due to right coronary artery occlusion. Percutaneous intervention failed, and it was determined that coronary dissection progressed retrograde, across the truncus of the aorta. Ascending aortic grafting and coronary bypass surgery were performed. The patient recovered and was discharged after 10 days. Close cardiothoracic observation is mandatory in patient evaluation and management.  相似文献   
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