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71.
Pseudoangiosarcomatous squamous cell carcinoma, also called pseudovascular, pseudoangiomatoid or adenoid pseudovascular carcinoma, is an uncommon and highly aggressive variant of squamous cell carcinoma. Histologically, it is characterized by proliferation of atypical keratinocytes with acantholysis and formation of pseudovascular spaces, forming anastomosed channels lined with neoplastic cells that invade the dermis. These cells are positive for cytokeratin and negative for vascular markers such as CD31 and CD34. There are few reports of this variant in the literature. Skin, breast, lung and vulva involvement have been described, but to the best of our knowledge, no cases involving the penis has been described. This study aims to describe the first case of angiosarcomatous squamous cell carcinoma of the penis. The patient presented with a painful lesion in the penis associated with urinary retention. Macroscopic findings exhibited an ulcerative vegetating lesion that involving the entire glans and part of the penile body, as well as infiltration of penile structures and scrotal skin. Microscopy shows atypical proliferation of sarcomatous keratinocyte pattern mimicking vascular spaces. Human papilloma virus (HPV) biomarkers and polymerase chain reaction (PCR) were all negative. Advanced penile squamous cell carcinoma with aggressive lymph node metastasis. This report presents the first case of penile pseudoangiosarcomatous squamous cell carcinoma, as an important differential diagnosis.  相似文献   
72.
Quality of Life Research - As people around the world are facing the Covid-19 outbreak, their perception of oral health problems could be changed. This study aimed to evaluate the immediate effects...  相似文献   
73.
A novel methodology for characterization of animal sperm shape involving the use of a spectral approach to multiscale curvature estimation is proposed. By using the derivative property of the Fourier transform, allied to Gaussian smoothing, accurate estimates of the curvature along the sperm contour can be obtained in such a way that the curvature peaks corresponding to the sperm head vertices can be effectively identified. The measurements derived from such a processing, namely the width of the basal region of the head, the centralization of tail implantation, and the multiscale bending energy, provide valuable resources for fertility and phylogenetic studies.  相似文献   
74.
A new technique to correct persistent left superior vena cava (LSVC) drainage into the left atrium is described in a 14-year-old patient with situs inversus, left atrial isomerism common atrium, and mitral valve regurgitation. During surgery, occlusion of the LSVC markedly increased the venous pressure, precluding its ligation. Because of the malposition of the heart and the unusual atrial anatomy, correction with an intra-atrial baffle was not attempted. After correcting the intra-cardiac anomaly, the LSVC was divided and anastomosed to the "right" atrial appendage using a segment of PTFE graft. The postoperative course was uneventful and an angiogram demonstrated excellent performance of the graft.  相似文献   
75.
We have studied the histopathological aspects related to the evolution of cutaneous lesions experimentally produced in the monkey Cebus apella (Primates: Cebidae) by Leishmania (V.) lainsoni, L. (V.) braziliensis and L. (L.) amazonensis. Microscopical examination of a series of biopsies obtained from these animals showed the kinetics of the cutaneous lesions regarding three species of Leishmania inoculated, as follows: 1) an initial non-specific chronic inflammatory infiltrate; 2) macrophagic nodules; 3) necrosis of parasitized phagocytic cells; 4) epitheliode granuloma; 5) absorption of the necrotic area (sometimes forming "foreign-body granuloma"); 6) a non-specific residual inflammatory infiltration; and 7) cicatrization. These pathological processes are, of course, responsible for both development and resolution of the leishmaniotic lesion. We also discuss some immunopathological mechanisms probably related with the sequential events, and that could be also responsible for the different clinical aspects found in man.  相似文献   
76.
妊娠期雌二醇和催乳素与瘦素的关系   总被引:2,自引:0,他引:2  
目的 研究妊娠期间性激素与瘦素水平之间的关系。方法 在180例不同孕周的妇女中,按孕周分为<20周组,20-23周组,≥28周组,采用酶联免疫吸附法测定其外周血血清雌二醇(E2)和催乳素(PRL),放射免疫法测定血清瘦素水平,分析这些激素之间的相互关系。结果 E2和PRL均随妊娠进展而逐步升高(P<0.0001),组间均有显著差异(P<0.05)。各组瘦素水平均高于非妊娠组,但组间差异无显著性。瘦素水平与孕妇体重及体重指数显著相关(P0.01),与PRL也呈相关(P<0.05),而与E2无明显相关。结论 PRL水平与妊娠期瘦素水平升高有一定关系。  相似文献   
77.
目的:用定量超声方法对有骨折史的骨质疏松症患者进行骨量检查,方法用CUBA Clinical型定量骨密度超声仪对393例被疑为骨质疏松的患者进行检测,并根据病史按有无骨折中进行分组。分析二组患者宽频超声衰减(BUA)、超声速率(VOS)、强度指数(SI)与骨折次数的关系。结果:伴有骨折史的骨质疏松症虱的BUA、VOS、SI值都要比无骨折史的患者明显降低(P=0.000)。结论定量超声值与骨折的发生次数呈负相关,其测定值越低,骨折的发生次数越多;骨的质量下降是造成骨质疏松骨折的主要原因。  相似文献   
78.
To assess the efficacy of quinolones in the prophylaxis of infections in neutropenic patients with acute non-lymphocytic leukemia, and to evaluate the emergence of quinolone resistance in two University Hospitals in Brazil, we retrospectively compared 101 consecutive episodes of neutropenia managed with quinolone prophylaxis between 1989 and November 1993, and 26 previous episodes without prophylaxis, and reviewed the results of in vitro sensitivity of Gram-negative strains to quinolones in the same period. Prophylaxis with quinolones resulted in less episodes of bacteremias (21% vs. 69%, p=10(-7)), including Gram-negative bacteremias (6% vs. 38%, p=10(-5)), with no statistically significant difference in the death rate (18% vs. 31%, p=0.14, 95% confidence interval -6-32). The resistance of Gramnegative strains to quinolones rose from 7% to 18% between 1990 and 1993 (p=10(-5)). The resistance against ceftazidime and amikacin, the agents used in the empirical antibiotic therapy, increased in the same proportion as the quinolones. Given the limited benefit of quinolones as prophylaxis and the increasing number of quinolone-resistant Gram-negative strains observed in our hospitals, the use of quinolones as prophylaxis must be seriously questioned. A stricter control of the use of quinolones in these hospitals might decrease resistance.  相似文献   
79.
The varicella vaccine developed by Takahashi and cols. in 1974, in Japan, shows outstanding features. Its development, site and route of administration and final results are reviewed in this article.The varicella vaccine is highly effective in normal children (with almost 100% seroconversion rate), and with good protective responses in immunocompromised children (82% to 90% seroconversion rate). This is the first attenuated live virus vaccine that may be recommended for these patients. Its indications and side effects, along with needed precautions and contraindications are reviewed. Simultaneous administration of varicella vaccine with other vaccines can be done, each vaccine should be injected at different sites. New studies are ongoing for the association of the varicella vaccine with others vaccines. Several countries licensed this vaccine for administration in selected high-risk individuals. Probably, in the future, the varicella vaccine will be included in the preventive immunization schedule.  相似文献   
80.
The main objective of this study was to introduce among us this technique. In a first step, steatocrit was compared to Van de Kamer test for 30 fecal samples. A significant positive correlation was found. In a second step, a steatocrit value was determined for normal children aged 0 to 72 months. In children from 0 to 3 months of age, no influence was found of diet (whether exclusively maternal milk or artificial one) on steatocrit value. However, upto the age of 3 months a significant and negative correlation was found between age and steatocrit value. Finally, three age groups were identified with different steatocrit values, as follows: 0-1 month, 4.04%; 1-3 months, 1.38%, 3-72 months, 0.29%. Thus the steatocrit test for fecal fat excretion was again shown to be not only simple, rapid, painless and inexpensive but also a reliable one.  相似文献   
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