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81.
Coronavirus disease 2019 (COVID-19) has become a global pandemic with a high rate of transmission. Currently, there is a lack of vaccines and specific drugs for this newly-emerged virus. Timely diagnosis and treatment, as well as isolation of patients and virus carriers, contribute to the effective prevention and control of this epidemic. This review focuses on early stage COVID-19 diagnosis methods and strategies, highlighting the guiding role of laboratory indicators on treatment strategy formulation, and prognosis assessments.  相似文献   
82.

Objective

Intraoperative histopatological examination of the sentinel nodes enables selection of patients who need dissection of the regional lymphatic system during the same operation. The aim of this study is to evaluate the diagnostic value of intraoperative histopathological examination of the sentinel nodes in breast cancer and skin melanoma. Intraoperative histopathology of the sentinel nodes as a diagnostic method is used in patients with melanoma and breast cancer. Recent studies have proved it to be an effective method for evaluating the nodes in the final histopathology. Intraoperative histopathological examination of the sentinel nodes is not performed routinely and there is no clear position on this issue. In this paper we try to prove that intraoperative test gives patients the simultaneous benefits of removal of regional lymph nodes metastases and earlier initiation of adjuvant therapy.

Methods

The study comprises 137 patients with breast cancer and 35 patients with malignant skin melanoma. Sentinel nodes were intraoperatively sectioned and examined by means of the imprint method and frozen section evaluation. The patients with positive sentinel nodes underwent immediate dissection of regional lymph nodes. Those with negative sentinel nodes diagnosed in the intraoperative examination, but positive in final pathologic results, underwent subsequent dissection of regional lymph nodes.

Results

60 sentinel lymph nodes were found in 35 patients with skin melanoma. In 3 patients, 3 sentinel lymph nodes were false negative in the intraoperative histopathological examination. No false positive sentinel lymph nodes were found. 249 sentinel lymph nodes were found in the intraoperative histopathological examination in 137 patients with breast cancer. There were no false positive sentinel nodes, but there were 7 false negative sentinel nodes. In this study, only 5 (3.6%) patients with breast cancer and 3 (8.5%) patients with skin melanoma required another regional operation.

Conclusion

The method of intraoperative histopathological evaluation of the sentinel nodes enables identification of metastases in these lymph nodes and gives a possibility to carry out a one-step regional lymphadenectomy and start the adjuvant therapy earlier.  相似文献   
83.
Oral infection has become the most important transmission mechanism of Chagas disease in Brazil. For this study, the development of Trypanosoma cruzi infection in mice, induced by the oral and intraperitoneal (IP) routes, was compared. Four groups of Swiss mice were used to evaluate the influence of parasite genetics, number of parasites, inoculation volume and developmental stages on the development of the orally induced infection: 1 – blood trypomastigotes (BT) via oral; 2 – BT via IP; 3 – culture metacyclic trypomastigotes (MT) via oral; and 4 – culture MT via IP. Animals inoculated orally showed levels of parasitemia, as well as infectivity and mortality rates, lower than animals inoculated via IP, regardless of DTU (discrete typing unit) and inoculum. Animals infected with TcII showed higher levels of these parameters than did animals infected with TcI. The larger volume of inoculum showed a greater capacity to cause an infection when administered via the oral route. BT infection was more virulent than culture MT infection for both routes (oral and IP). However, mice inoculated orally with BT showed lower levels than via IP, while mice inoculated orally with culture MT showed similar levels of infection to those inoculated via IP. Mice inoculated with culture MT showed more histopathological changes than those inoculated with BT, regardless of the inoculation route. These results indicate that this alternative experimental model is useful for evaluating infection by T. cruzi isolates with subpatent parasitemia and low virulence, such as those belonging to the TcI and TcIV DTUs, which are prevalent in outbreaks of orally transmitted Chagas disease.  相似文献   
84.
目的测定绿色荧光蛋白转基因小鼠不同年龄段的生理生化、组织病理学等方面的指标,为该品种转基因小鼠应用于毒理学等领域研究提供理论依据。方法定期测定不同周龄段(4~6周龄,6~8周龄,9~12周龄,13~14周龄)141只绿色荧光蛋白转基因(GFP)小鼠和100只对照组C57BL/6J小鼠的体重和摄食量,对上述两种动物定期取血,测定血生化及血液学指标,对动物进行大体解剖,计算主要脏器(心、肝、脾、肺、肾、脑、胸腺,性腺)的脏器系数并进行组织病理学检测。结果①体重和摄食量:4周龄的GFP小鼠,其体重明显低于对照组,差异具有显著性(P<0.01);4~5周龄的GFP小鼠,其摄食量明显高于对照组,差异具有显著性(P<0.01)。②血常规测定:6~8周龄,9~12周龄的GFP小鼠,其红细胞计数(RBC)明显低于对照组,差异具有显著性(P<0.01);9~12周龄,13~14周龄的GFP小鼠,其白细胞计数(WBC)明显高于对照组,差异具有显著性(P<0.01)。③血生化测定:6~8周龄,9~12周龄,13~14周龄的GFP小鼠,其尿酸(UA)值明显高于对照组,差异具有显著性(P<0.01);6~8周龄,9~12周龄的GFP小鼠,其总蛋白(TP),白蛋白(ALB)明显低于对照组,差异具有显著性(P<0.01)。④脏器系数:6~8周龄,9~12周龄的GFP小鼠,其胸腺的脏器系数明显低于对照组,差异具有显著性(P<0.01);9~12周龄,13~14周龄的GFP小鼠,其肝脏的脏器系数明显高于对照组,差异具有显著性(P<0.01)。⑤病理检测:6~8周龄有部分GFP小鼠胸腺发育不良,其他受检脏器和其他年龄段动物未见明显病理改变。结论①绿色荧光蛋白转基因小鼠与对照组C57BL/6J小鼠相比,在体重(4周龄)、摄食量(4~5周龄)、血常规(红细胞计数RBC、白细胞计数WBC、血红蛋白HGB)、血生化(尿酸UA、总蛋白TP、白蛋白ALB)、脏器系数(胸腺,肝脏)等指标上存在明显差异,但是其值均在正常范围内。②绿色荧光蛋白转基因小鼠在6~8周龄有部分小鼠胸腺发育不良。  相似文献   
85.
目的:颅骨过度气化(Craniocervical bone pneumatisation)比较少见,近年来对其报道和认识逐渐增多。本文介绍一例偶然发现的颅骨过度气化的影像表现并对相关文献进行复习。方法:分析我院1例颅骨过度气化的影像学图像。并从国外pubmed数据库(www.pubmed.gov)及国内中国知网数据库(www.cnki.net)查找发表的文献进行文献复习。结果:颅骨过度气化表现为颅骨的气腔形成并局部膨出,多为偶然发现或因并发症就诊,可涉及颅盖骨、颅底骨及颈椎等,近年来对其认识逐渐增多。结论:颅骨过度气化尽管少见,对征象的认知有助于相关科室医师正确识别此征象,从而有利于临床一些相关疑难病例的诊断和操作并对防止漏、误诊具有一定的意义。  相似文献   
86.
心电检查网络平台近年来是医院信息化建设的热点,我院根据医院实际情况,分析了部署心电网络时涉及到的网络结构、数据交换、数据格式等实际问题,并成功实施了该项目。  相似文献   
87.
AimThe aim is to find out why the rate of recurrence of tongue and floor of the mouth cancer is so high despite radical surgical treatment combined with radiochemotherapy.BackgroundOropharyngeal cancer is the second most common head and neck cancer in Poland. Tongue cancers account for 40% of all oral cavity tumours. A frequent reason for a failure in treatment of tongue and floor of the mouth cancers is local recurrence. Based on that examination, cancer treatment can be precisely planned.Materials and methodsThe study comprised a group of 56 tongue and floor of the mouth cancer patients. 9 patients who showed local recurrence were given an extended histopathological examination. The infiltration of the vessels, nerves and muscles was examined. The examination also checked the largest dimension of the tumour, the greatest depth of invasion from the mucous membrane, invasive front of the cancer, vessel embolisms, intra- and perineural infiltrations in the cancer invasive front. Tumour aggressiveness was assessed according to M. Brandwein-Gensler.ResultsIn five patients, primary tumours were found to be histologically aggressive as indicated by the infiltration of the vessels, nerves and muscles. Tumours which penetrate these structures were characterized with peri- and intraneural infiltration and were correlated with the depth of invasion from the mucous membrane, the occurrence of embolisms, and a high risk assessment as proposed by M. Brandwein-Gensler.ConclusionThe progression of cancer depends strongly on histopathological traits. The incidence of penetration of the vessels, nerves and muscles correlates with aggressiveness of the tumour front.  相似文献   
88.
食品中细菌快速测定的方法学研究   总被引:1,自引:0,他引:1  
通过对现代细菌数量检测方法的研究 ,探讨其必然的发展趋势 ,为寻求更快更好的方法找到其出路。同时也为现在的各种检测的方法的实质找到其必然的归宿。  相似文献   
89.
水体中大肠杆菌的生物检测法—斑贝检测法   总被引:2,自引:0,他引:2  
大肠杆菌是水体污染程度的重要指示菌 ,因而对其要求快速、准确的检测。常规检测法的优点是简便、快速 ,但缺点是当菌数过多会影响准确计数 ,而菌体过少则会出现漏检的情况。综述了一种新的大肠杆菌生物检测法 ,该法应用斑贝作为预测水体中菌密度升高的一种指示生物 ,因其具备快速积累并保留水体中大肠杆菌的能力 ,可有效地避免低菌数时的漏检情况 ,能使水域管理者降低正常监测大肠杆菌临界量所需的取样频率 ,因而提供了一个更高效的细菌污染的河水监测方案。  相似文献   
90.
基于等位基因InDel快速检测黑木耳原生质体单核体   总被引:1,自引:1,他引:0  
范秀芝  周雁  边银丙 《菌物学报》2014,33(2):273-279
以黑木耳 Auricularia auricula-judae栽培菌株Au916三磷酸甘油醛脱氢酶(GAPDH)两个等位基因中的InDel为基础,以原生质体再生菌株为研究材料,建立了基于InDel的黑木耳原生质体单核体检测技术,并采用荧光显微镜检和配对试验对此方法进行了验证。应用InDel能清晰地区分黑木耳双核体和两种原生质体单核体,且不同的单核体之间可以进行交配,其杂交双核体能正常出耳,结果表明基于等位基因InDel标记可以快速准确地检测黑木耳原生质体单核体。在大规模测序获得真菌基因组信息的基础上,InDel标记在原生质体单核体鉴定中的应用将更加普遍。  相似文献   
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