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1.
2.
Cytologic evaluation of the CSF is often difficult when trying to distinguish between truly neoplastic and reactive cells. Several non-neoplastic conditions may be associated with atypical cells in the CSF, a fact the clinician has to consider to avoid inadequate aggressive theraphies. We report here three patients with infectious meningitis (due to Herpes zoster virus in two, and neuroborreliosis in one) and cytologically atypical cerebrospinal fluid lymphocytes. Further characterization showed that the pleocyrosis in these patients was of reactive origin. Cytomorphology is frequently insufficient and histochemical, immuncytochemical and cellular genome analysis techniques may help differentiate atypical reactive cells from neoplastic cells. 相似文献
3.
目的:探讨常见呼吸道发热疾病的临床特点及与传染性非典型肺炎(严重急性呼吸综合症,SAGS)的鉴别。方法:发热门诊诊治的以发热体温高于38℃伴呼吸道症状患者702例,对病因、临床表现、实验室检查、胸部X线、治疗及转归进行比较。结果:常见呼吸道发热患者中,急性上呼吸道感染596例占总数的85%,577病例白细胞计数不高占82%,淋巴细胞计数不降低,X线检查正常或仅有支气管炎表现。有基础肺部或全身疾病患者,虽然有发热,但往往以肺部或全身原发疾病相应症状为重要或首发表现,可有气急,体温以中度发热为主,78%病例有白细胞计数及中性比例升高。胸片除肺炎改变外,多有肺部基础疾病的表现,抗生素治疗有效;而单纯性肺炎胸部X线多表现为节段性或局灶性肺炎。这部分病例也以发热为主要或首发症状,一般表现为咳嗽、咳痰,气急少见,易与SARS混淆。结论:临床呼吸道发热疾病以急性上呼吸道感染最多见,容易忽略,要注意筛查。单纯性肺炎与SARS的鉴别,应结合流行病史、治疗反应及实验室检查结果进行。 相似文献
4.
Pekka Saikku 《Clinical microbiology and infection》1997,3(6):599-604
The main atypical pathogens in respiratory tract infections are classified on the basis of their ability to cause atypical pneumonia. This is not a well-defined clinical entity, and it is evident that atypical pathogens can sometimes cause 'typical' pneumonias and vice versa. This emphasizes the need for microbiological diagnosis, since it affects the selection of proper treatment, in which β-lactam antibiotics and aminoglycosides are not effective. Moreover, mixed infections caused by atypical and typical pathogens together are common. At this moment rapid and sensitive diagnostic methods are lacking. Besides numerous viruses, the main bacterial pathogens causing atypical pneumonias are Mycoplasma pneumoniae , two chlamydia species. Chlamydia pneumoniae and C. psittaci , one rickettsia, Coxiella burnetti , and several Legionella species. The majority of these pathogens cause upper respiratory tract infections more often than overt pneumonias. An atypical agent, Chlamydia pneumoniae , has also been associated with chronic inflammatory conditions in the cardiovascular system. The most recently discovered pathogen in atypical pneumonias is a hantavirus causing hantavirus pulmonary syndrome. 相似文献
5.
Expression of cyclin D1, retinoblastoma gene protein, and p16 MTS1 protein in atypical adenomatous hyperplasia and adenocarcinoma of the lung 总被引:2,自引:0,他引:2
Y. Kurasono Takaaki Ito Yoichi Kameda Nobuo Nakamura Hitoshi Kitamura 《Virchows Archiv : an international journal of pathology》1998,432(3):207-215
To clarify the events leading to the disruption of cell growth control that occurs during the development of pulmonary adenocarcinoma
(AC), we used immunohistochemistry to evaluate the expression of G1 cycle regulators, cyclin D1, Rb protein (pRb), and p16
MTS1 protein and the tumour proliferation marker, Ki 67, both in AC of the lung and in its precursor lesion, atypical adenomatous
hyperplasia (AAH). The frequency of lesions with cyclin D1 overexpression was relatively high in AAH (47–89%), but was decreased
in early AC (28%) and overt AC (35%). The loss of pRb expression was rare in both AAH (0–18%) and early AC (0%), and was infrequent
even in overt AC (13%). The loss of p16 expression was also relatively infrequent in both the premalignant and the malignant
lesions (11–25%). Our results suggest that overexpression of cyclin D1 is an early event and plays an important part in tumorigenesis
in the case of lung AC. However, cyclin D1 overexpression is not required for the development and maintenance of a malignant
phenotype. It is likely that some cyclin D1-independent pathways other than Rb and p16 abnormalities have an important role
in the malignant transformation from AAH to early AC.
Received: 8 July 1997 / 26 September 1997 相似文献
6.
Kawauchi S Okuda S Morioka H Iwasaki F Fukuma F Chochi Y Furuya T Oga A Sasaki K 《Human pathology》2005,36(10):1096-1100
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction. 相似文献
7.
Usual human livers contain two major ALDH isozymes, i.e., cytosolic ALDH1 and mitochondrial ALDH2, while approximately 50% of Orientals are "atypical" and have only the ALDH1 and are missing the ALDH2. Instead, the atypical livers contain an enzymatically inactive but immunologically cross-reactive material (CRM) corresponding to the ALDH2 component. Some Orientals are found to be atypical also in the ALDH1 locus, i.e., they are missing the enzymatically active ALDH1 but contain a large amount of CRM corresponding to the ALDH1 component. cDNA for ALDH1 and that for ALDH2 were cloned and their nucleotide sequences were determined. The amino acid sequences of ALDH1 and ALDH2 were deduced from their cDNA sequences. The molecular abnormality of the inactive ALDH2(2) is found to be the substitution of Glu at the 14th position from the COOH-terminal of the protein by Lys which resulted from G----A transition in the gene. 相似文献
8.
Clozapine as a drug of dependence 总被引:1,自引:0,他引:1
Rationale: In schizophrenics, clozapine has been reported to induce various withdrawal signs and rapid onset relapse to psychosis on
cessation of chronic treatment. Objective: The study was designed to develop an animal model of one aspect of clozapine tolerance and withdrawal using core body temperature
measures. Methods: Two groups of 15 female Wistar rats were treated chronically (b.i.d.) with clozapine at 6 or 12 mg/kg per injection for
21 days prior to cessation of drug treatment, withdrawal being studied over 4 consecutive days. Body temperatures were assessed
daily throughout the study. Results: Acutely, clozapine induced dose-related hypothermia, to which complete tolerance developed in both groups, the development
of tolerance being more rapid in the group treated with 6 mg/kg per injection of clozapine. During withdrawal only the group
treated chronically with 12 mg/kg per injection of clozapine showed rapid onset significant hyperthermia. This dissipated
progressively over days, and was completely absent after 4 days of withdrawal. Conclusions: Clozapine induced a clear somatic withdrawal sign after chronic treatment. It is suggested that, in future research in both
humans and animals, it is important to attempt to differentiate between clozapine withdrawal and clozapine withdrawal-induced
relapse to psychosis. It is also important to characterise the clozapine withdrawal syndrome fully in animals; to establish
the neurochemical mechanisms involved in such withdrawal; and to determine which novel antipsychotics are most efficacious
in inducing clozapine-like withdrawal effects, in suppressing clozapine withdrawal, and in preventing relapse to psychosis
in patients being transferred from clozapine to novel atypical antipsychotic drugs.
Received: 14 May 1998/Final version: 14 September 1998 相似文献
9.
We report five patients with atypical parkinsonism characterized by freezing phenomenon, akinesia and axial rigidity without limb rigidity or tremor. These patients were selected from 252 patients with parkinsonism who were referred to our clinic from 1986 to 1993. They have common clinical features consisting of freezing phenomena involving all four extremities, especially in the initiation of walking, and marked axial rigidity; otherwise, neither supranuclear ophthalmoparesis nor nuchal dystonia was noted. Their clinical features did not change over several years except in one patient who later developed typical manifestations of progressive supranuclear palsy (PSP). Levodopa was of no effect on their symptoms. After excluding other possibilities, it is our conclusion that they represent an atypical form of PSP lying between the pure akinesia of Imai and Narabayashi and the typical form of PSP. 相似文献
10.
广东地区环境水源和临床标本嗜肺军团菌培养与基因快速鉴定 总被引:9,自引:2,他引:9
目的建立嗜肺军团菌培养与基因快速鉴定方法,探讨广东地区环境水源和非典型肺炎患者嗜肺军团菌感染状况。方法对广东地区采集的57份中央空调冷凝塔水、30份湖泊水和53份临床标本,用本室改良BCYE-α培养基作培养和PCR试验。结果57份中央空调冷凝塔水培养检出嗜肺军团菌20株(35.1%),PCR检测LP-DNA阳性38份(66.7%);30份湖泊水细菌培养均阴性,PCR阳性4份(13.3%);53例非典型肺炎患者支气管洗液和痰液细菌培养均阴性,PCR阳性5例(9.4%);本实验设计的PCR扩增引物,只和标准嗜肺军团菌和本地分离株产生反应;不与其他病原菌扩增,而显示其良好特异性;本PCR敏感性可检出检体中0.6个细菌DNA含量。结论广东地区环境水源中普遍存在嗜肺军团菌,是引起非典型肺炎的重要病源之一。 相似文献