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31.
目的着重探讨45例缺血性肠病患者的病因、CT检查技术及其影像表现。资料与方法45例缺血性肠病均经螺旋CT扫描。26例经过手术证实,14例经过治疗痊愈,5例急性死亡。结果其中肠系膜动脉缺血24例,肝固有动脉缺血4例,肠系膜静脉缺血17例。结论严格掌握CT检查技术,根据CT影像表现并密切结合临床,对缺血性肠病患者可以作出确定诊断。  相似文献   
32.

Background  

Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP.  相似文献   
33.

BACKGROUND.

The ThinPrep Imaging System (TIS) has been approved by the U.S. Food and Drug Administration for use to decrease the number of false‐negative results in ThinPrep (TP) gynecologic specimens and increase cytotechnology productivity. Although the increased detection of squamous abnormalities using the TIS has been well documented, to the authors' knowledge, data regarding the impact of the TIS in the detection of glandular abnormalities is limited. The goal of the current study was to evaluate the effectiveness of the TIS in detecting glandular abnormalities in cervicovaginal specimens.

METHODS.

TIS evaluated TP tests with histologic confirmation of adenocarcinoma involving the gynecologic system were included in the current study. Two cytotechnologists independently reviewed the cases for the presence or absence of atypical glandular cells. Review results were correlated with initial cytologic and histologic diagnoses.

RESULTS.

A total of 124 cases met the criteria for inclusion in the current study. Seventy of these cases (56%) were found to contain atypical glandular cells on the TP slide. TIS was able to identify atypical cells in 97% of these cases (68 of 70 cases). Nine cases initially reported as benign were found to contain atypical glandular cells on secondary review. All but 1 of these cases contained atypical glandular cells detected by the TIS. The majority of these false‐negative cases (6 of 9 cases) derived from endometrial adenocarcinoma. No cytologic evidence of a glandular abnormality was found in the 54 remaining cases.

CONCLUSIONS.

The TIS was found to be effective in identifying atypical glandular cells in specimens containing malignant glandular cells, leading to a full review of the slide. Cancer (Cancer Cytopathol) 2008. © 2007 American Cancer Society.  相似文献   
34.
35.
Adenocarcinoma in situ (ACIS) of the uterine cervix is an increasingly recognized disease. Thirty-seven cases were reviewed to determine the effect of HPV, marital status, parity, smoking habit and age on the topography and behaviour of this lesion. Using a commercial probe, 25% of 28 lesions tested were positive for HPV 16/18. The presence of HPV and a history of smoking appeared to exert no significant influence upon the topography and behaviour of ACIS. Nulliparity and a history of never being married was associated with a significant reduction in the incidence of coexisting CIN lesions. Age less than 36 years was associated with a significant reduction in the proximal linear extent of ACIS. While hysterectomy is probably the definitive treatment for ACIS of the cervix, there is an important place for conservative management by conization alone. Patients younger than 36 years are most likely to be desirous of retained fertility and appear to have the lesions most amenable to conservative surgery.  相似文献   
36.
The Significance of Mild Squamous Atypia on Cytology   总被引:2,自引:0,他引:2  
Summary: Between January, 1991 and February, 1993 inclusive, 396 Papanicolaou smears were reported to show Mild Squamous Atypia with or without Human Papilloma Virus (MSA ± HPV). All women with MSA ± HPV smears were routinely recalled for colposcopy. To determine the significance of MSA ± HPV on routine smear screening, the records of all patients were reviewed.
Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion.
It is concluded that all asymptomatic women with MSA ± HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months.  相似文献   
37.
38.
目的探讨肝局灶性结节增生(FNH)不典型的螺旋CT征象。方法对病理证实或临床确诊的32例FNH患者37个病灶的螺旋CT征象进行回顾性分析。结果 37个病灶中,有 14个病灶直径≤3 cm,23个病灶直径>3 cm;7个病灶周边存在假包膜;22个病灶存在中央瘢痕, 其中有20个病灶直径>3 cm;所有病灶在动脉期均呈高密度,其中31个病灶肿瘤实质均匀强化。结论多发病灶、存在假包膜、无中央瘢痕、动脉期不均匀强化是FNH不典型的CT征象。征象的多样性与病灶的病理类型和病灶的直径相关。  相似文献   
39.
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to their low spontaneous tumour incidence and their increased sensitivity towards the lymphomagen ethylnitrosourea these mice may present an interesting model for short-term carcinogenicity testing. Here, we report on the further exploration of this transgenic mouse model with two additional carcinogens known to have, among others, the lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and 12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week (by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1 mice during the observation period of 40 weeks. B[a]P also induced tumours of the forestomach within this observation period, though at a lower incidence and apparently equally effective in wildtype and transgenic mice. TPA, on the other hand, was unable to induce lymphomas (or tumours in any other organ) in either transgenic or wildtype animals within the observation period of 44 weeks, when applied dermally at the maximum tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular analysis showed that B[a]P-induced lymphomas in transgenic mice were of T-cell origin, 80% of which had elevated levels of c-myc expression. None of the lymphomas had increased N-myc expression and mutation analysis of the ras-gene family revealed a K-ras mutation in only one out of eight tumours investigated. Also, none of the lymphomas showed aberrant expression of p53 as determined by immunohistochemistry. It is concluded that the E mu-pim-1 mouse model will not be very suitable for short-term carcinogenicity testing in general: only genotoxic chemicals that have the lymphohaematopoietic system as target for carcinogenesis in wild- type mice, appear to be efficiently identified.   相似文献   
40.
目的寻求制作门静脉高压动物模型的最佳方法,并以此为基础从事肝硬化后门静脉血液动力学基础研究。方法以3组共15只兔为动物模型,分别以0.2%、0.4%、0.8%浓度的白芨粉为栓塞材料,开腹注入兔门静脉内,手术前后行门静脉测压、血管造影及病理学检查,最长观察时间阎周.结果以0.4%浓度白芨粉制作门静脉高压模型最佳,4周后肝脏体积缩小20%,门静脉压平均升高40%,病理呈典型坏死后肝硬化表现。结论以白芨粉为栓塞材料制作肝硬化门静脉高压动物模型方法简单、效果可靠已重复性好.以不同浓度的白芨栓塞剂来控制坏死后肝纤维化的程度是本试验的一大特点,本动物模型的建立对深入研究肝硬化门静脉高压的成因及治疗措施有着重要意义。  相似文献   
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