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81.
To elucidate the anatomic distal ligament of the human glans penis and associated clinical implications, we compared the structures of the glans penis and corpora cavernosa in dogs, rats, and humans. From May 2001 to March 2003, gross dissection, microscopic examinations, and stains for elastic fibers and collagen subtypes were made in the penises of 11 adult human male cadavers, 7 dogs, and 5 rats. A distal ligament in the human glans penis replaces the os penis that is present in dogs or rats, also termed the baculum, but retains collagen types I and III as common structural and interlocking components, respectively. The intercavernosal septum is complete, and intracavernosal pillars (ICPs) are abundant in dogs, absent in rats, and moderately developed in humans. A tunica with numerous elastic fibers exists to fulfill the requirements of erectile function in humans but not in dogs or rats, since it is essential for establishing tissue strength to serve as a buttress. We may conclude that in dogs and rats, the strong os penis is designed for ready intromission and is associated with a pair of well-developed nonelastic corpora to serve as a buttress for the os penis. These structures are necessary for the rigorous coitus observed in dogs. The less compliant corpus cavernosum is suitable for the flipping action observed in a mating male rat. These specific anatomic designs may provide explanations for the individual requirements for the specific physiologic functions that differ from species to species. Although there is no os in the human glans, a strong equivalent distal ligament is arranged centrally and acts as a supporting trunk for the glans penis. Without this important structure, the glans could be too weak to bear the buckling pressure generated during coitus and too limber to serve as a patent passage for ejaculation, and it could be too difficult to transmit the intracavernosal pressure surge along the entire penis during ejaculation. Given the common histologic nature of the distal ligament, which is associated with the tunica albuginea and serves a similar function as the os penis observed in the dog and the rat, one may ask whether the healing process of a tunica may take as long as that required in a bony structure. Further research is required to answer this question.  相似文献   
82.
Our aim was to study retrospectively the destiny of the deep dorsal vein of the penis in the event of its stripping surgery or its simple ligation in patients diagnosed with venoocclusive dysfunction 17 years ago. From June 1986 to May 1987, a total of 31 men were seen for erectile dysfunction due to venous leakage resulting from priapism, aging, or congenital or idiopathic factors. Of these, 23 men underwent venous stripping of the deep dorsal vein and are referred to as the stripping group. The remaining 8 patients received a simple ligation of the deep dorsal vein and are classified as the ligation group. A total of 21 patients (16 of the 23 and 5 out of the 8) were available for follow-up by using the abridged 5-item version of the International Index of Erectile Function (IIEF-5) scoring system and cavernosograms. In the ligation group, the imaging demonstrates some compensatory veins that are commensurate with impotence postoperatively. In the stripping group, however, the follow-up cavernosograms disclosed no venous recurrence, but residual ones that were not crucial to the rigidity. The IIEF-5 scoring in the ligation group changed from a preoperative mean IIEF-5 score of 10.0 +/- 4.5 to 9.8 +/- 3.6 postoperatively. In the stripping group, however, the mean preoperative IIEF-5 score of 9.8 +/- 4.1 increased to a mean postoperative IIEF-5 score of 18.9 +/- 2.1. Although there was no significant difference between the 2 groups' preoperative IIEF-5 score, there was a statistically significant difference between treatments (P <.001). The penile venous vasculature bears no evidence of regeneration even as long as 17 years after their removal. This finding is in contrast to what is commonly believed, that erectile dysfunction will recur about 2 years after ligation of the deep dorsal vein. We therefore believe that the clinical recurrence may not be due to venous regeneration, and penile venous surgery, if properly performed, may be durable, although larger studies will be required.  相似文献   
83.
Brain abscess: clinical experience and analysis of prognostic factors   总被引:9,自引:0,他引:9  
Xiao F  Tseng MY  Teng LJ  Tseng HM  Tsai JC 《Surgical neurology》2005,63(5):442-9; discussion 449-50
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84.
Acute small bowel obstruction is a common problem, especially for those patients with previous abdominal surgery that can cause postoperative adhesions. Acute, non-postoperative small bowel obstruction is less common and has various etiologies. We report a case of acute small bowel obstruction without previous abdominal surgery. The patient underwent laparoscopic exploration, and a congenital band was found to cause direct compression of the ileum and entrapment of a segment of bowel loop. There was evidence of bowel strangulation. The color and peristalsis of the entrapped bowel loop recovered gradually after division of the band, and segmental bowel resection was avoided. He has remained asymptomatic since the procedure. We suggest early and aggressive surgical intervention for patients with acute, non-postoperative small bowel obstruction to avoid possible complications of bowel strangulation and gangrene. A laparoscopic approach may be a safe, feasible, and favorable option for correct diagnosis and appropriate treatment in this situation.  相似文献   
85.
Epileptogenesis in chronically injured cortex: in vitro studies   总被引:8,自引:0,他引:8  
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86.
Simultaneous impactions of first, second, and third permanent molars comprises a very rare clinical situation with diverse therapeutic approaches and is a difficult challenge for dentists. Early diagnosis and treatment of eruption disturbances contributes to optimal outcomes. This article reports the treatment of a teenager with severe impaction of right mandibular first, second, and third molars, which hinders the masticatory function and dental arch integrity. A decision-making process and a simple orthodontic technique are described. To shorten the treatment time and simplify the procedures, the impacted right mandibular third and second molars were orthodontically uprighted with an innovative tip-back cantilever. Subsequently, the deeply impacted right mandibular first molar was extracted with minimal obstacles. The combined surgical-orthodontic approach resolved a challenging clinical problem and eliminated the need for prosthetic or dental implant replacement of the impacted molars. Good occlusion, normal function, and a healthy periodontium of the patient were also achieved.  相似文献   
87.
Betel quid (BQ) chewing is a common oral habit in South Asia and Taiwan. BQ consumption may increase the risk of oral squamous cell carcinoma (OSCC), oral submucous fibrosis (OSF), and periodontitis as well as systemic diseases (atherosclerosis, hypertension, etc.). However, little is known about the toxic effect of BQ components on endothelial cells that play important roles for angiogenesis, carcinogenesis, tissue fibrosis, and cardiovascular diseases. EAhy 926 (EAHY) endothelial cells were exposed to arecoline, a major BQ alkaloid, for various time periods. Cytotoxicity was estimated by 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. The cell cycle distribution of EAHY cells residing in sub-G0/G1, G0/G1, S-, and G2/M phases was analyzed by propidium iodide staining of cellular DNA content and flow cytometry. Some EAHY cells retracted, became round-shaped in appearance, and even detached from the culture plate after exposure to higher concentrations of arecoline (> 0.4 mM). At concentrations of 0.4 and 0.8 mM, arecoline induced significant cytotoxicity to EAHY cells. At similar concentrations, arecoline induced G2/M cell cycle arrest and increased sub-G0/G1 population, a hallmark of apoptosis. Interestingly, prolonged exposure to arecoline (0.1 mM) for 12 and 21 days significantly suppressed the proliferation of EAHY cells, whereas EAHY cells showed adaptation and survived when exposed to 0.05 mM arecoline. These results suggest that BQ components may contribute to the pathogenesis of OSF and BQ chewing-related cardiovascular diseases via toxicity to oral or systemic endothelial cells, leading to impairment of vascular function. During BQ chewing, endothelial damage may be induced by areca nut components and associate with the pathogenesis of OSF, periodontitis, and cardiovascular diseases.  相似文献   
88.
PURPOSE: To examine the efficacy of photodynamic therapy with verteporfin (VPDT) for treatment of subfoveal choroidal neovascularization (CNV) in patients with pathologic myopia. METHODS: In a prospective study, adult patients (18 years of age or older) with new onset subfoveal CNV were treated in two tertiary centers with the standard protocol of VPDT. Snellen best-corrected visual acuity was measured at baseline and at 1 month, 3 months, 6 months, 12 months, 15 months, 18 months, and 24 months after VPDT. Stratified analyses for single and multiple treatments and different age groups were performed by paired t-tests, and the results were compared with baseline findings. RESULTS: Thirty-three patients with single VPDT and 13 patients with multiple treatments were enrolled for analysis. Significant improvement in measurement of visual acuity was found after 24 months of follow-up for the group with single therapy. For patients receiving multiple treatments, an improving trend was not as clear. In prognosis analysis by age groups in the single-treatment group, the younger group had better mean visual acuity at the end of the 24-month study period than the older group. Improvement was much more evident in the younger group, although it was not statistically significant at every follow-up time point. CONCLUSION: In patients with response to single VPDT, visual acuity significantly improved over a 2-year period. In patients receiving multiple treatments, improvement was not as distinctive, suggesting alternative treatment options might be relevant for this subgroup.  相似文献   
89.
PURPOSE: To evaluate how sutureless amniotic membrane patches may affect visual functions in normal human eyes. DESIGN: Prospective intervention study. METHODS: Ten sets of sutureless amniotic membrane patch manufactured as PROKERA were inserted in one eye of six normal patients. Four sets (one each) were inserted in four patients, while six sets (three each) were inserted in two patients. Uncorrected distant and near visual acuities, color vision, amniotic membrane thickness measured by pachymetry, and total symptom scores were compared before and after insertion. RESULTS: Within 30 minutes after insertion, mean distant visual acuities decreased from -0.22 +/- 0.06 to 0.92 +/- 0.45 logarithmic minimum angle of resolution (logMAR). Among 10 sets of PROKERA inserted, the largest optotype (1.0 logMAR) of the near vision chart could not be recognized in five, but color vision evaluated by Panel D-15 was still preserved in all. Total symptom scores increased to 47.8 +/- 9.1 points (maximum, 100 points). Among symptoms, total scores for foreign body sensation (17.8 +/- 3.6) and blurred vision (17.8 +/- 4.4) were high. Loss of distant visual acuity and increases of symptom scores were not correlated with amniotic membrane thickness, of which the mean was 67.6 +/- 25.2 mum. However, amniotic membrane that was less opaque tended to provide relatively good visual acuities. CONCLUSION: Because of the relative non-transparency of sutureless amniotic membrane patches in PROKERA, distant and near visual acuities decreased in normal human eyes. The foreign body sensation noted after insertion is primarily derived from the rigid supporting skirt.  相似文献   
90.
报道了β-阻滞剂塞利洛尔的简便制备方法,即以对乙氧基苯胺为原料,经酰胺化,傅克反应,以环氧氯丙烷取代,最后用叔丁胺直接与环氧基反应开环等4步反应制得。比文献五步反应缩短了一步,产物经元素分析、红外光谱、核磁共振谱、质谱等分析确定结构。  相似文献   
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