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51.
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.  相似文献   
52.
为比较盐酸二甲双胍和糖适平对Ⅱ型糖尿病的治疗效果,通过33例Ⅱ型糖尿病患者服用二甲双胍和35例Ⅱ型糖尿病患者服用糖适平,观察4mo后发现二甲双胍在降低血糖、24h尿糖定量,降低血脂及逆转外周神经病变方面有显著疗效。但二甲双胍不能升高血浆C—肽水平,不能降低24h尿蛋白质定量。如能将二甲双胍和糖适平联合应用将会提高疗效,减轻副作用。  相似文献   
53.
We present two children with massive bleeding into the serous body cavities accompanied by intractable consumption coagulopathy. One had a large spleen palpable at admission, the other developed progressive splenomegaly while in hospital. Neither child had any external evidence of angiomatous lesions. A splenic hemangioma was suspected clinically and on abdominal ultrasound; the diagnosis was confirmed at laparotomy. Splenectomy resulted in a prompt cure in both cases.  相似文献   
54.
A sensitive and specific method has been developed to detect hepatitis B virus (HBV) in serum. The method involves two steps: the capture of viral genome from serum using a high affinity IgM monoclonal antibody directed against a common a domain epitope found on the envelope, and the amplification of viral DNA by the polymerase chain reaction (PCR). The amplification is initiated using "generic" primers derived from the core and pre-core sequences which are highly conserved amongst the hepadnaviruses. This rapid technique detects less than 10 infectious virions and may be useful in the study of individuals with acute and chronic liver disease of unknown etiology.  相似文献   
55.
Surgical treatment of intracavernous neoplasms: a four-year experience   总被引:1,自引:0,他引:1  
Forty-two patients with neoplasms involving the cavernous sinus had operations between 1983 and 1987. The lesions included 25 benign tumors (e.g., meningioma, neurilemoma) and 17 malignant tumors (e.g., chondrosarcoma, adenoid cystic carcinoma). The cavernous sinus was entered by inferior, anterolateral, or medial extradural approaches or by superior or lateral intradural approaches. The intracavernous internal carotid artery was managed by dissecting tumor away from it or by occlusion and excision with or without direct vein graft reconstruction, based on the results of a preoperative balloon occlusion test. Cranial nerves III, IV, V, and VI usually were dissected from tumor, but in 3 cases of tumor invasion, the excised nerve segment was reconstructed by direct suture or with a sural nerve interposition graft. Twenty-one of the benign tumors and 8 of the malignant tumors were excised totally and the remainder subtotally. On follow-up ranging from 3 to 48 months, one subtotally excised meningioma recurred and was treated with re-excision and adjuvant radiation therapy. Two "totally" excised malignant tumors recurred outside the cavernous sinus at the margins of excision. There was no operative mortality or permanent cerebral morbidity. Postoperatively, the ocular and neurological function of most patients was similar to the preoperative status; in some, it was significantly improved. Thirteen additional patients with intracavernous neoplasms also were evaluated during the same period and followed without operation. The early follow-up information regarding these patients is provided.  相似文献   
56.
Cytogenetic analysis using C-, G-, and Ag-nucleolus organizer region (NOR) staining techniques, performed on established cell lines as well as directly processed breast tumor effusions, revealed that: 1) chromosome No. 1 is involved in translocation; 2) based on 1q translocation chromosome, breast tumors could be classified into two groups; and 3) double minutes and homogeneously staining regions may be present in breast tumor cells in vivo as well as in vitro, and that homogeneously staining regions may exhibit some heterogeneity in staining.  相似文献   
57.
目的 探讨新生儿C6PD缺陷病和晚发性维生素K缺乏症的危害与预防措施。方法 回顾分析1995-2000年儿内科住院的1周-2月(不含2月)的婴儿3104例次,其中病死56例。结果 1周-2月的小婴儿占住院患儿的19.34%,其中新生儿G6PD缺陷病239例,占7.70%;晚发性维生素K缺乏症92例,占2.96%。死因的第2、3位分别是晚发性维生素K缺乏症(13例,占23.21%)和新生儿C6PD缺陷病(12例,占21.43%),两者的病死率分别为14.13%和5.02%,极显著高于(x^2=17.59,P<0.01)或相近于(x^2=0.88,P>0.05)肺炎的3.57%。新生儿G6PD缺陷病合并感染占38.49%、低氧血症占23.35%、低血糖占19.25%、酸中毒占15.90%,继发胆红素脑病占13.81%。晚发性维生素K缺乏症出现抽搐占90.22%、胃肠、注射部位出血占60.89%;CT证实颅内出血占98.91%。结论 1周-2月的小婴儿约占住院患儿的两成,新生儿G6PD缺陷病和晚发性维生素K缺乏症的病死率均很高,两者是除肺炎外最主要的死因。提议制定并推广预防这2种疾病的常规措施,并参照国内外相应的现状拟出其具体内容。  相似文献   
58.
Oxygen consumption of slices of rat submandibular gland was monitored with an oxygen electrode method. Carbachol stimulated an immediate increase in tissue respiration that was inhibitable by ouabain. The stimulation required the presence of calcium in the incubation medium and was blocked by atropine. The calcium ionophore A23187 also stimulated ouabain-sensitive oxygen consumption in the tissue slices. The results show that the mechanism using the extra energy during cholinergic stimulation is the sodium pump. Amiloride at a 1, 10, or 100 microM concentration had no effect on stimulation of ouabain-sensitive respiration by carbachol. Since amiloride, which is known to block the sodium reabsorption process in the ductal segment, has no effect on the stimulation, the increased sodium pump activity is probably located in the acinar region and is associated with the primary fluid secretion process.  相似文献   
59.
In the present investigation a method of quantifying electromyograms (EMG's) from different muscle groups of the body to evaluate total muscular activity is described. A unipolar pickup, i.e., one standard silver cup surface electrode over each active muscle, was used because the EMG outputs with this electrode configuration during the same muscular activity were found to be greater than those with a bipolar pickup, i.e., two electrodes over each muscle. It was observed that for the purpose of quantification the root mean square (r.m.s.) value of a ‘steady’ level or the average r.m.s. value of a varying level of EMG is related in a linear fashion to the absolute mean value of the wave obtained by integrating the EMG for a specified time interval after making the waveform unidirectional. A similar relationship was observed with different voltage levels from a noise generator which was used for calibration purposes. EMG's from different muscle groups during isometric as well as isotonic voluntary contractions were found to summate together outside the body in a manner similar to noise voltages, i.e., the r.m.s. value of the combined voltages is equal to the square root of the sum of the mean square values of the individual waves. A method of passing EMG's through a summing amplifier and then quantifying the output for the evaluation of total muscular activity was developed, which greatly reduces the system components normally necessary for such studies. The results obtained from a series of experiments are discussed in detail.  相似文献   
60.
Reactive oxygen species (ROS) contribute significantly to myocardial ischaemia-reperfusion (I-R) injury. Recently the combination of the antioxidants vitamin E (VE) and alpha-lipoic acid (alpha-LA) has been reported to improve cardiac performance and reduce myocardial lipid peroxidation during in vitro I-R. The purpose of these experiments was to investigate the effects of VE and alpha-LA supplementation on cardiac performance, incidence of dysrhythmias and biochemical alterations during an in vivo myocardial I-R insult. Female Sprague-Dawley rats (4-months old) were assigned to one of the two dietary treatments: (1) control diet (CON) or (2) VE and alpha-LA supplementation (ANTIOXID). The CON diet was prepared to meet AIN-93M standards, which contains 75 IU VE kg-1 diet. The ANTIOXID diet contained 10 000 IU VE kg(-1) diet and 1.65 g alpha-LA kg(-1) diet. After the 14-week feeding period, significant differences (P<0.05) existed in mean myocardial VE levels between dietary groups. Animals in each experimental group were subjected to an in vivo I-R protocol which included 25 min of left anterior coronary artery occlusion followed by 10 min of reperfusion. No group differences (P>0.05) existed in cardiac performance (e.g. peak arterial pressure or ventricular work) or the incidence of ventricular dysrhythmias during the I-R protocol. Following I-R, two markers of lipid peroxidation were lower (P<0.05) in the ANTIOXID animals compared with CON. These data indicate that dietary supplementation of the antioxidants, VE and alpha-LA do not influence cardiac performance or the incidence of dysrhythmias but do decrease lipid peroxidation during in vivo I-R in young adult rats.  相似文献   
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