全文获取类型
收费全文 | 910篇 |
免费 | 99篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 41篇 |
妇产科学 | 15篇 |
基础医学 | 171篇 |
口腔科学 | 16篇 |
临床医学 | 98篇 |
内科学 | 166篇 |
皮肤病学 | 48篇 |
神经病学 | 83篇 |
特种医学 | 41篇 |
外科学 | 101篇 |
综合类 | 37篇 |
一般理论 | 1篇 |
预防医学 | 104篇 |
眼科学 | 16篇 |
药学 | 37篇 |
中国医学 | 1篇 |
肿瘤学 | 32篇 |
出版年
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 11篇 |
2020年 | 8篇 |
2019年 | 16篇 |
2018年 | 22篇 |
2017年 | 10篇 |
2016年 | 14篇 |
2015年 | 16篇 |
2014年 | 31篇 |
2013年 | 33篇 |
2012年 | 36篇 |
2011年 | 54篇 |
2010年 | 32篇 |
2009年 | 33篇 |
2008年 | 34篇 |
2007年 | 38篇 |
2006年 | 44篇 |
2005年 | 33篇 |
2004年 | 47篇 |
2003年 | 36篇 |
2002年 | 38篇 |
2001年 | 29篇 |
2000年 | 24篇 |
1999年 | 26篇 |
1998年 | 24篇 |
1997年 | 21篇 |
1996年 | 14篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 12篇 |
1992年 | 14篇 |
1991年 | 19篇 |
1990年 | 24篇 |
1989年 | 20篇 |
1988年 | 12篇 |
1987年 | 16篇 |
1986年 | 16篇 |
1985年 | 22篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1981年 | 9篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1975年 | 5篇 |
1974年 | 5篇 |
1973年 | 8篇 |
1972年 | 4篇 |
1971年 | 5篇 |
排序方式: 共有1011条查询结果,搜索用时 15 毫秒
1.
Multicentric reticulohistiocytosis. Detailed immunophenotyping confirms macrophage origin 总被引:1,自引:0,他引:1
J R Salisbury P A Hall H C Williams M H Mangi G J Mufti 《The American journal of surgical pathology》1990,14(7):687-693
A case study of multicentric reticulohistiocytosis is presented with extensive immunohistochemical studies of the infiltrate in both paraffin and cryostat sections. These studies showed that the cells are of monocyte/macrophage origin. B- and T-cell gene rearrangement analysis of multicentric reticulohistiocytosis was also performed and showed a germline configuration. 相似文献
2.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
3.
4.
5.
Motoaki Nakamura Dean F Salisbury Yoshio Hirayasu Sylvain Bouix Kilian M Pohl Takeshi Yoshida Min-Seong Koo Martha E Shenton Robert W McCarley 《Neuropsychopharmacology》2007,62(7):773-783
BACKGROUND: Overall neocortical gray matter (NCGM) volume has not been studied in first-episode schizophrenia (FESZ) at first hospitalization or longitudinally to evaluate progression, nor has it been compared with first-episode affective psychosis (FEAFF). METHODS: Expectation-maximization/atlas-based magnetic resonance imaging (MRI) tissue segmentation into gray matter, white matter (WM), or cerebrospinal fluid (CSF) at first hospitalization of 29 FESZ and 34 FEAFF, plus 36 matched healthy control subjects (HC), and, longitudinally approximately 1.5 years later, of 17 FESZ, 21 FEAFF, and 26 HC was done. Manual editing separated NCGM and its lobar parcellation, cerebral WM (CWM), lateral ventricles (LV), and sulcal CSF (SCSF). RESULTS: At first hospitalization, FESZ and FEAFF showed smaller NCGM volumes and larger SCSF and LV than HC. Longitudinally, FESZ showed NCGM volume reduction (-1.7%), localized to frontal (-2.4%) and temporal (-2.6%) regions, and enlargement of SCSF (7.2%) and LV (10.4%). Poorer outcome was associated with these LV and NCGM changes. FEAFF showed longitudinal NCGM volume increases (3.6%) associated with lithium or valproate administration but without clinical correlations and regional localization. CONCLUSIONS: Longitudinal NCGM volume reduction and CSF component enlargement in FESZ are compatible with post-onset progression. Longitudinal NCGM volume increase in FEAFF may reflect neurotrophic effects of mood stabilizers. 相似文献
6.
7.
SUMMARY Event-related potential (ERP) recordings were used to investigate the nature of auditory stimulus evaluation during stage 2 sleep. Frequent and rare stimuli, differing in intensity and frequency, were presented to six adult subjects while awake and asleep. The latency and voltage distribution of one of the long-latency components evoked during sleep resembled the P3 component evoked while awake. However, it was attenuated in voltage and superimposed on N3, a large late negative component, most probably the slow potential of the K complex. The identification of a P3-like potential during sleep suggests that the P3 potential is not solely a marker of active cognitive processes, but contains a small component which reflects automatic, pre-attentive evaluation of deviant stimuli. 相似文献
8.
Synovial sarcoma: an immunohistochemical study 总被引:4,自引:0,他引:4
The immunohistochemical staining pattern of 18 cases of synovial sarcoma with two epithelial-specific monoclonal antibodies is described. This is compared with normal synovium, cases of giant cell tumour of tendon sheath (benign synovioma) and a variety of spindle celled sarcomas. Sixteen cases of synovial sarcoma showed staining of the epithelial component with at least one antibody. No staining was seen in normal synovium or in giant cell tumours of tendon sheath. A small number of malignant schwannomas contained groups of cells which stained positively whilst other spindle cell sarcomas either did not stain or showed 'cross-reaction' type staining only. These results add weight to the proposition that synovial sarcomas do not arise from normal synovium, despite their morphological similarities, but from mesenchymal connective tissue. It is also shown that immunohistochemical staining with anti-epithelial antibodies will emphasize the biphasic pattern of synovial sarcomas allowing their distinction from other sarcomas. 相似文献
9.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
10.