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71.
We have screened exon 12 of the low density lipoprotein (LDL) receptor gene from 46 familial hypercholesterolemia (FH) heterozygotes and 64 normolipidemic controls for two polymorphisms, Hindi , which is caused by a T to C substitution at base 1773, and a C to T transition at base 1725, by using single strand conformation polymorphism (SSCP) analysis. Our results indicate that polymorphism at base 1725, previously reported as very rare from a Japanese sample, is quite frequent in the Spanish population and that it is closely linked to the presence of the Hindi site ( Hinc II+). Thus, both polymorphisms constitute a system of three alleles, typed Hinc II-C1725, Hinc II+C1725, and Hinc II+T1725, whose frequencies in the FH sample were 0.489,0.347, and 0.164, respectively. No significant differences were found in the allele frequencies between the FH and control samples. This three-allelic polymorphic system provides a higher information content (PIC value) than the Hindi RFLP alone (0.537 versus 0.373, respectively); therefore, it is an extremely useful marker for linkage analysis of FH in Caucasian populations.  相似文献   
72.
Male infertility is a clinical manifestation which concerns approximately 15 % of all couples in Europe. Male causes for infertility are found in 50% of involuntarily childless couples. For Germany this counts for a number of an equivalent of 50 000 men/year, No causal factor is found in 60%-75% of cases (idiopathic male infertility). Nevertheless, reduced male fertility can be the result of congenital and acquired urogenital abnormalities, increased scrotal temperature (varicocele), endocrine disturbances, genetic abnormalities and immunological factors. Furthermore, urogenital inflammations and infections play an important role. Indications for microbiological assessment include abnormal urine samples, urinary tract infections, prostatitis, epididymitis, orchitis, ejaculate infections and sexually transmitted diseases. In the following review, different infectious diseases of the male urogenital tract and their implications on fertility were reviewed.  相似文献   
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Seventy-six patients underwent parathyroidectomy for renal hyperparathyroidism.There were 10 subtotal parathyroidectomies, 49 total parathyroidectomieswith implantation of part of one gland as an autograft, ninetotal parathyroidectomies with no autograft, and eight patientsin whom only three parathyroid glands were found. In 34 dialysis patients who underwent total parathyroidectomywith an autograft there was a high rate of recurrent hyperparathyroidismafter 6 years in those remaining on dialysis. Fifty per centhad asymptomatic recurrent hyperparathyodism and 30 per centrequired partial autograft excision for symptomatic hyperparathyroidism.In contrast, recurrent hyperparathyroidism was rare in renaltransplant recipients with good renal function. This favourableoutcome did not depend upon whether parathyroid surgery wasperformed before or after transplantation, or on the type ofparathyroidectomy. Total parathyroidectomy without an autograftwas performed in nine dialysis patients without any short-termadverse effects, and with clinical and pathological improvementin bone disease. In summary, the results of surgery for renal hyperparathyroidismwere excellent in patients who received a successful renal transplant.However, there was a high incidence of recurrent hyperparathyroidismin patients who remained on long-term dialysis. Total parathyroidectomywithout an autograft may be the treatment of choice in patientsunlikely to receive a renal transplant.  相似文献   
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Nonobstructive Dysphagia in Reflux Esophagitis   总被引:2,自引:0,他引:2  
Dysphagia in the absence of organic esophageal stricture may occur in patients with reflux esophagitis. Although the exact mechanism of this "nonobstructive dysphagia" (NOD) is not known, it is believed to be related to transient segmental esophageal motor disorder. The goals of this study were to determine the frequency of NOD in patients with reflux esophagitis and correlate it with esophageal pH and motility changes. Sixty-three consecutive patients with symptoms of esophageal dysfunction were studied with endoscopy, infusion esophageal manometry, and 24-h ambulatory esophageal pH monitoring. Forty-seven had severe erosive esophagitis unresponsive to medical therapy; 16 with esophageal motility disorders were used as symptomatic controls. Twenty-eight of 63 patients studied experienced NOD during the 24-h pH study; 22 had esophagitis and six had esophageal dysmotility without esophagitis. NOD was noted with similar frequency in the two groups; 22/47 (46.8%) of patients with esophagitis and 6/16 (37.5%) with esophageal dysmotility experienced NOD during the period of study. NOD correlated with pH less than 4.0 in 88.6% of patients with esophagitis but in only 7% of patients with esophageal dysmotility (p less than 0.001). There was no difference in acid reflux patterns in esophagitis patients who experienced NOD (22/47), and in those who did not (25/47). There was no correlation between NOD and baseline esophageal motility abnormalities. In summary, 1) NOD is a common, intermittent symptom that occurred in up to 46.8% of esophagitis patients and 37.5% of symptomatic controls during the 24-h period of this study; 2) NOD correlates with esophageal pH less than 4.0 in patients with esophagitis and not in patients with esophageal dysmotility. These data strongly suggest that acid in the distal esophagus frequently triggers the sensation of dysphagia in esophagitis patients, but not in patients with esophageal motility disorders. Combined ambulatory intraesophageal motility and pH monitoring may further elucidate the mechanism of dysphagia in these patients.  相似文献   
78.
The change in transfer coefficient (Kco) with increasing heart rate during exercise was studied in 25 normal subjects and in 21 patients with pulmonary sarcoidosis. The slope of the Kco response against heart rate was found to be 0·0053 mmol min−1 kPa−1 l−1 per beat in the normal group but in many of the patients was two standard deviations or more below this normal slope, even when their routine function tests were normal. This response of Kco to exercise is a more sensitive index of changed function than more routine function tests in pulmonary sarcoidosis.  相似文献   
79.
Cervical spine trauma accounts for majority of spinal injuries, and approximately one‐third involve the craniocervical junction (CCJ). Due to its high sensitivity, magnetic resonance imaging (MRI) has become the standard tool for imaging suspected ligamentous injuries in an unstable spine and in patients with neurological deficits having a normal CT. The ligamentous anatomy of the CCJ is complex, and thorough knowledge is a prerequisite for accurate interpretation of the MRI findings. This pictorial essay aims to familiarise radiologists with the ligamentous anatomy, mechanisms of injury and MRI appearances of injuries in the cervical spine, with emphasis on the CCJ.  相似文献   
80.
目的探索内镜下经扩大鼻蝶入路显露斜坡区的可行性,为切除斜坡区病变提供解剖学参考。方法在10例成人头部固定标本上,内镜下模拟扩大经鼻蝶手术入路显露斜坡区,观察有关显微解剖标志。结果扩大经鼻蝶内镜入路可磨除从鞍后到斜坡、枕骨大孔前缘的骨性结构;可显露斜坡区腹侧硬膜下的椎基底动脉及其分支、后交通动脉及其与大脑后动脉汇合处、动眼神经、脑干腹侧等结构。此入路的手术标志主要包括:蝶筛隐窝、蝶窦开口、视神经隆突、颈内动脉隆突与颈内动脉视神经隐窝、咽结节、枕骨大孔前缘。结论内镜下扩大经鼻蝶手术入路可充分显露鞍后-斜坡区的腹侧硬膜下结构,适用于此区病变的手术治疗。  相似文献   
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