全文获取类型
收费全文 | 14774篇 |
免费 | 1110篇 |
国内免费 | 399篇 |
专业分类
耳鼻咽喉 | 247篇 |
儿科学 | 689篇 |
妇产科学 | 292篇 |
基础医学 | 1654篇 |
口腔科学 | 349篇 |
临床医学 | 1266篇 |
内科学 | 1304篇 |
皮肤病学 | 289篇 |
神经病学 | 707篇 |
特种医学 | 1221篇 |
外国民族医学 | 6篇 |
外科学 | 2211篇 |
综合类 | 1567篇 |
现状与发展 | 4篇 |
预防医学 | 311篇 |
眼科学 | 208篇 |
药学 | 610篇 |
11篇 | |
中国医学 | 129篇 |
肿瘤学 | 3208篇 |
出版年
2024年 | 33篇 |
2023年 | 216篇 |
2022年 | 492篇 |
2021年 | 570篇 |
2020年 | 538篇 |
2019年 | 438篇 |
2018年 | 408篇 |
2017年 | 425篇 |
2016年 | 531篇 |
2015年 | 542篇 |
2014年 | 918篇 |
2013年 | 1006篇 |
2012年 | 786篇 |
2011年 | 779篇 |
2010年 | 641篇 |
2009年 | 609篇 |
2008年 | 720篇 |
2007年 | 685篇 |
2006年 | 624篇 |
2005年 | 547篇 |
2004年 | 481篇 |
2003年 | 352篇 |
2002年 | 303篇 |
2001年 | 281篇 |
2000年 | 239篇 |
1999年 | 234篇 |
1998年 | 252篇 |
1997年 | 223篇 |
1996年 | 218篇 |
1995年 | 186篇 |
1994年 | 219篇 |
1993年 | 143篇 |
1992年 | 148篇 |
1991年 | 167篇 |
1990年 | 138篇 |
1989年 | 121篇 |
1988年 | 118篇 |
1987年 | 89篇 |
1986年 | 103篇 |
1985年 | 118篇 |
1984年 | 110篇 |
1983年 | 68篇 |
1982年 | 85篇 |
1981年 | 101篇 |
1980年 | 77篇 |
1979年 | 63篇 |
1978年 | 46篇 |
1977年 | 41篇 |
1976年 | 29篇 |
1975年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
The cytologic features of ascitic fluid in a case of malignant fibrous histiocytoma (MFH) of the colon are described. At autopsy, two solid tumor masses were found around the ascending and transverse colon, accompanied by about 3,000 ml of ascites. Tumor cells had infiltrated diffusely into the outer layers of almost all of the gastrointestinal wall, simulating peritonitis carcinomatosa. Cytologic examination of the ascites revealed various kinds of tumor cells; short spindle-like cells, multinucleated giant cells, and round cells with an invaginated nuclear margin, forming small clusters. These cytologic findings were considered to be very useful in the diagnosis of MFH, especially in cytologic examinations of ascites. ACTA PATHOL JPN 38: 921 ∼ 928, 1988. 相似文献
82.
家猪心脏纤维支架的大体解剖 总被引:1,自引:1,他引:1
目的 观察猪心纤维支架 ,为猪心的研究和比较解剖学积累资料。方法 取甲醛固定后的猪心2 7例 ,液态塑料浸渍的塑化猪心 5例 ,解剖显示纤维支架后用游标卡尺进行观测。结果 猪心左纤维三角的三边分别平均为 17 4 1± 1 99mm、18.96± 3.2 6mm和 17.6 4± 2 .4 4mm ;右纤维三角三边分别为 15 .83± 2 .11mm、16 .19± 1.94mm和 2 0 .96± 2 .6 2mm ;二尖瓣环、三尖瓣环的周长平均为 73.0 0± 9.71mm ,6 8.89±7.2 4mm ;主动脉瓣环和肺动脉瓣环直径分别为 18.4 4± 2 .89mm和 16 .0 3± 2 .6 3mm ;猪Todaro腱呈扁带状 ,走行部位较深 ,且分支较人心多 ,长度为 2 0 98± 4 2 0mm。结论 猪心纤维支架与人类形态结构相似 ,但瓣环周长和Todaro腱形态有一定差别。 相似文献
83.
Miroslav Makek Hans Jörg Leu 《Virchows Archiv : an international journal of pathology》1982,397(3):241-250
Summary We present the case of a sacrococcygeal chordoma which recurred 15 years after the radical removal as a soft tissue tumor in the gluteal musculature. This tumor consisted of two parts: a chordoma without symptoms of aggressive cellular proliferation and a malignant fibrous histiocytoma. During the following 4 years several local recurrences of the malignant fibrous histiocytoma occurred in the gluteal musculature. The patient finally died of lung metastases. No chordoma tumor tissue was found in the lungs, in the gluteal musculature or in the sacrococcygeal bone area. Histology including electron microscopy revealed no proof of a transition of chordoma into malignant fibrous histiocytoma. It must be assumed that the secondary soft tissue tumor originated from residual chordoma cells which were implanted during the operation of the primary tumor. It remains unclear whether the malignant fibrous histiocytoma arose from mesenchymal stromal cells within the chordoma or directly from primitive neuroectodermal chorda cells which possess the ability to differentiate into a variety of cell types including mesenchymal cells. 相似文献
84.
Coindre JM Hostein I Maire G Derré J Guillou L Leroux A Ghnassia JP Collin F Pedeutour F Aurias A 《The Journal of pathology》2004,203(3):822-830
Inflammatory malignant fibrous histiocytoma (inflammatory MFH) is a very rare tumour that occurs most often in the retroperitoneum. So far, it has been considered to be a special subtype of MFH. As it is now widely accepted that most retroperitoneal pleomorphic MFHs are dedifferentiated liposarcomas, the present study compared histological features, genomic profile (CGH analysis), and MDM2 and CDK4 status (immunohistochemistry, FISH, and quantitative PCR) in inflammatory MFHs from 12 patients and dedifferentiated liposarcomas that had an inflammatory MFH component from eight patients. Metaphase cytogenetic and FISH analyses were also performed on one inflammatory MFH. Histological review showed areas of well-differentiated liposarcoma in nine inflammatory MFHs. CGH analysis showed 12q13-15 amplification or gain in six of seven inflammatory MFHs and in seven of seven dedifferentiated liposarcomas. Immunohistochemistry showed positivity of tumour cells for MDM2 in every tumour in both groups and for CDK4 in ten and seven inflammatory MFHs and dedifferentiated liposarcomas, respectively. Metaphase cytogenetic and FISH analysis performed on one inflammatory MFH showed the presence of a supernumerary large marker chromosome and ring chromosome with high-level amplification of both MDM2 and CDK4 genes. FISH analysis on paraffin wax-embedded sections showed amplifications of MDM2 and CDK4 in seven of seven inflammatory MFHs and in seven of seven dedifferentiated liposarcomas. Quantitative PCR showed amplification of MDM2 in six and of CDK4 in seven of nine inflammatory MFHs. In conclusion, this study strongly suggests that most so-called inflammatory MFHs are dedifferentiated liposarcomas. 相似文献
85.
正常国人腰间盘纤维软骨粘弹性实验研究 总被引:3,自引:0,他引:3
研究了正常国人急性外伤致死的成人新鲜尸体10个腰间盘L3-4、14-5纤维软骨的力学性质。以一维拉伸的方法得出了L3-4、L4-5腰间盘纤维软骨的破坏载荷、伸长比、Lagrange张应力、Lagrange张应变等数据。以多项式,用回归分析方法得出椎间盘L3-4、L4-5纤维软骨的应力-应变关系表达式及应力-应变曲线。还对椎间盘L3-4、L4-5纤维软骨进行拉伸应力松弛、蠕变实验。得出了椎间盘L3-4、L4-5纤维软骨的归一化应力松弛函数、蠕变函数G(t)、J(t)表达式。以冯元桢教授的软组织大变形准线性理论,构建了L3-4、L4-5椎间盘纤维软骨的松弛函数K(λ,t)=G(t)T^(e)(λ)的表达式,对实验结果进行分析讨论。 相似文献
86.
G. Holstege L. Meiners K. Tan 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,58(2):379-391
Summary Injections of HRP in the nucleus raphe magnus and adjoining medial reticular formation in the cat resulted in many labeled neurons in the lateral part of the bed nucleus of the stria terminalis (BNST) but not in the medial part of this nucleus. HRP injections in the nucleus raphe pallidus and in the C2 segment of the spinal cord did not result in labeled neurons in the BNST. Injections of 3H-leucine in the BNST resulted in many labeled fibers in the brain stem. Labeled fiber bundles descended by way of the medial forebrain bundle and the central tegmental field to the lateral tegmental field of pons and medulla. Dense BNST projections could be observed to the substantia nigra pars compacta, the ventral tegmental area, the nucleus of the posterior commissure, the PAG (except its dorsolateral part), the cuneiform nucleus, the nucleus raphe dorsalis, the locus coeruleus, the nucleus subcoeruleus, the medial and lateral parabrachial nuclei, the lateral tegmental field of caudal pons and medulla and the nucleus raphe magnus and adjoining medial reticular formation. Furthermore many labeled fibers were present in the solitary nucleus, and in especially the peripheral parts of the dorsal vagal nucleus. Finally some fibers could be traced in the marginal layer of the rostral part of the caudal spinal trigeminal nucleus. These projections appear to be virtually identical to the ones derived from the medial part of the central nucleus of the amygdala (Hopkins and Holstege 1978). The possibility that the BNST and the medial and central amygdaloid nuclei must be considered as one anatomical entity is discussed.Abbreviations AA
anterior amygdaloid nucleus
- AC
anterior commissure
- ACN
nucleus of the anterior commissure
- ACO
cortical amygdaloid nucleus
- AL
lateral amygdaloid nucleus
- AM
medial amygdaloid nucleus
- APN
anterior paraventricular thalamic nucleus
- AQ
cerebral aqueduct
- BC
brachium conjunctivum
- BIC
brachium of the inferior colliculus
- BL
basolateral amygdaloid nucleus
- BNSTL
lateral part of the bed nucleus of the stria terminalis
- BNSTM
medial part of the bed nucleus of the stria terminalis
- BP
brachium pontis
- CA
central nucleus of the amygdala
- Cd
caudate nucleus
- CI
inferior colliculus
- CL
claustrum
- CN
cochlear nucleus
- CP
posterior commissure
- CR
corpus restiforme
- CSN
superior central nucleus
- CTF
central tegmental field
- CU
cuneate nucleus
- D
nucleus of Darkschewitsch
- EC
external cuneate nucleus
- F
fornix
- G
gracile nucleus
- GP
globus pallidus
- HL
lateral habenular nucleus
- IC
interstitial nucleus of Cajal
- ICA
internal capsule
- IO
inferior olive
- IP
interpeduncular nucleus
- LC
locus coeruleus
- LGN
lateral geniculate nucleus
- LP
lateral posterior complex
- LRN
lateral reticular nucleus
- MGN
medial geniculate nucleus
- MLF
medial longitudinal fascicle
- NAdg
dorsal group of nucleus ambiguus
- NPC
nucleus of the posterior commissure
- nV
trigeminal nerve
- nVII
facial nerve
- OC
optic chiasm
- OR
optic radiation
- OT
optic tract
- P
pyramidal tract
- PAG
periaqueductal grey
- PC
cerebral peduncle
- PO
posterior complex of the thalamus
- POA
preoptic area
- prV
principal trigeminal nucleus
- PTA
pretectal area
- Pu
putamen
- PUL
pulvinar nucleus
- R
red nucleus
- RF
reticular formation
- RM
nucleus raphe magnus
- RP
nucleus raphe pallidus
- RST
rubrospinal tract
- S
solitary nucleus
- SC
suprachiasmatic nucleus
- SCN
nucleus subcoeruleus
- SI
substantia innominata
- SM
stria medullaris
- SN
substantia nigra
- SO
superior olive
- SOL
solitary nucleus
- SON
supraoptic nucleus
- spV
spinal trigeminal nucleus
- spVcd
spinal trigeminal nucleus pars caudalis
- ST
stria terminalis
- TRF
retroflex tract
- VC
vestibular complex
- VTA
ventral tegmental area of Tsai
- III
oculomotor nucleus
- Vm
motor trigeminal nucleus
- VI
abducens nucleus
- VII
facial nucleus
- Xd
dorsal vagal nucleus
- XII
hypoglossal nucleus 相似文献
87.
Takanori Hirose Toshiaki Sano Junichi Abe Kazuo Hizawa Shigeki Hatakeyama Itsumi Mori 《Ultrastructural pathology》1988,12(5):529-536
A case of recurrent soft part sarcoma with focal areas showing epithelial differentiation in the right thigh in a 78-year-old woman is reported. The primary tumor consisted of myxoid areas and solid areas, in which relatively uniform epithelioid tumor cells were arranged in sheets, whereas pleomor-phism and a storiform pattern appeared in the recurrent tumors. Thus this tumor was suspected to be a malignant fibrous histiocytoma. However, further studies showed unexpected ultrastructural and immunohistochemical features. Cytokeratin immu-noreactivity and tonofilamentlike structures probably indicated epithelial differentiation of some tumor cells. From the clinical and histological findings, this tumor should be identified as a malignant fibrous histiocytoma with phenotypic expressions of epithelial cell. 相似文献
88.
Fukunaga M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(4-5):304-308
A rare case of fibromyxoma arising in the stomach of a 78-year-old male is presented. A well-defined, encapsulated tumor measuring 27x17x8 cm showed a lobular growth in the submucosa and muscularis propria, with no association with the propria mucosa. Histologically, the tumor was characterized by a diffuse, widely spaced proliferation of small spindle, stellate and round cells with dendritic outlines with fibromyxoid stroma. Neither cellular atypia nor mitotic figures were observed. Immunohistochemically, the tumor was positive for vimentin and CD34 but negative for CD117, alpha-smooth muscle actin, muscle actin, desmin and S-100 protein. Ultrastructurally, the tumor cells had irregularly shaped nuclei and cytoplasm containing moderate amounts of mitochondria, rough endoplasmic reticulum, subplasmalemmal densities, and short interdigitating processes. These findings indicated the fibroblastic nature of the tumor. The patient was well without recurrence 20 months after surgery. It is important to recognize that gastric fibromyxoma is a distinct entity and to include it in the differential diagnosis of gastric mesenchymal tumors, as the tumors show a different clinical behavior and as limited surgery with local excision is possible. 相似文献
89.
Clinical stage I seminomas are effectively treated with surgery raising concerns as to when to give adjuvant radiation therapy given the risk of secondary malignancies. A recent randomized trial found tumor size and rete testis invasion to be the strongest predictors of relapse in clinical stage I seminomas. These 2 parameters may be surrogate measures of tumor volume. Intertubular seminoma (ITS) of the testis describes the presence of neoplastic germ cells within the interstitium of the testis. These cells are detected away from the main macroscopic mass. Because ITS can infiltrate in a 3-dimensional fashion, it may also represent a measure of tumor volume not usually noted in standard pathology reporting. The goal of this study was to determine the incidence of ITS in pure seminomas and its association with other prognostic parameters. One hundred twenty consecutive pure seminomas surgically removed between 1998 and 2003 were evaluated. ITS was defined as the presence of an interstitial or intertubular growth pattern of tumor cells, which was noncontiguous with the main tumor and present at least 3 high-power fields away from the tumor mass. The average tumor size was 3.4 cm. Of the entire cohort of patients, which included pathological stages T1 through T3, 11% had invasion through the tunica albuginea, 51% had rete testis invasion, 51% had lymphovascular invasion, 93% had associated intratubular germ-cell neoplasia, and 36% had ITS. ITS was significantly associated with rete testis invasion ( P = .001). Logistic regression analysis looking at ITS, tumor size, patient age, and lymphovascular invasion revealed that only ITS was associated with rete testis invasion (RR, 4.1, P < .0001). ITS is present in a significant proportion of pure seminomas and has a significant association with rete testis invasion. The presence of ITS may therefore be an important prognostic factor, not only because it alters the calculated size of the tumor but also because it has an association with rete testis invasion. 相似文献
90.
M. Satya Murthy Edward F. Scanlon Ralph H. Silvermant Clyde R. Goodheartt Robert A. Goldschmidt Mary Lou Jelachich 《Clinical & experimental metastasis》1993,11(2):159-173
Fibronectins are a family of glycoproteins with modular functional domains. They mediate cell-cell and cell-matrix interactions which are important in embryogenesis, wound healing, metastasis and other processes. We present data on the influence of fibronectin on wound implantation of a murine mammary carcinoma line, TA3Ha. Fibronectin used in these studies was derived from bovine plasma, human serum, human foreskin fibroblasts, and mouse embryo cultures. TA3Ha cells rarely form tumors in the liver of syngeneic mice when injected intravenously but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Wound implantation is markedly reduced when the cells are pre-exposed to 200 µg/ml bovine plasma fibronectin (13%, P = 0.007), human serum fibronectin (0%, P = 0.02), human cellular fibronectin (0%, P = 0.02), or mouse cellular fibronectin (0%, P = 0.04). Lung colonization is also reduced by these fibronectins. These effects are not due to a cytotoxic action of fibronectin, since intraperitoneally injected fibronectin-treated cells form ascites tumor as effectively as do control untreated cells. Local application of a solution containing 0.25 mg/ml mouse cellular fibronectin to the hepatic wound reduces the frequency of tumor implantation from 45% to 5% (1/21, P = 0.001). No tumor implantation inhibition is seen when only suspending medium or albumin in suspending medium is used. The mechanism by which topical application of fibronectin reduces hepatic wound implantation of tumor cells is unclear, but this finding raises an exciting possibility of preventing local recurrence of cancer. 相似文献