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21.
Mixed dysembryoplastic neuroepithelial tumor and ganglioglioma 总被引:3,自引:0,他引:3
We report a case of a 15-year-old girl with new onset seizures, who had a mixed dysembryoplastic neuroepithelial tumor (DNT)
and ganglioglioma of the right parieto-occipital lobe. The tumor appeared well demarcated and exhibited a low T1 and a high
T2 signal on magnetic resonance imaging. Architecturally it was in large part intracortical and multinodular, but also featured
a leptomeningeal component. The former corresponded to DNT, a proliferation of oligodendroglia-like cells (OLCs) arranged
in nodules, as well as comprising a diffuse internodular element featuring “floating neurons” in a mucoid matrix. The leptomeningeal
portion of the lesion was a ganglioglioma consisting of large neurons and astrocytes in association with marked desmoplasia.
Spacially, the two components abutted one another but appeared distinct. Immunohistochemistry showed the neurons of the ganglioglioma
to be positive for class III β-tubulin, synaptophysin, and chromogranin A, whereas the astrocytic cells stained only for glial
fibrillary acidic protein. Most OLCs in the DNT were positive for S-100 protein. This apparently mixed lesion suggests that
a close histogenetic relationship exists between DNT and ganglioglioma. We postulate that the pluripotential progenitor cells
residing in the subpial granular layer may have given rise to the cortical DNT and to the leptomeningeal ganglioglioma. To
our knowledge, this is the first detailed histological, immunochemical and ultrastructural report of a mixed DNT and ganglioglioma.
Received: 11 August 1997 / Revised, accepted: 24 November 1997 相似文献
22.
Professor C. Martin J. -P. Auffray C. Badetti G. Perrin L. Papazian F. Gouin 《Intensive care medicine》1992,18(2):101-104
Continous monitoring of mixed venous (SvO2) and central venous (ScO2) oxygen saturation was compared in 7 critically-ill patients (Apache II score: 19±2.1) to determine whether or not information derived from ScO2 were reliable in clinical practice. Patients were catheterized with both a pulmonary artery (PA) and a central venous (CV) catheter, each of them mounted with fiberoptic sensors (Opticath PA Catheter P7110 and Opticath CV Catheter U440, Abbott). A total of 580 comparative measurements were obtained during periods without and with therapeutic interventions (drug-titration, bronchial suction, use of PEEP, changes in FiO2...). The systematic error between the 2 measurement techniques was 0.6% and 0.3% in periods with and without therapeutic interventions, respectively. The variability between the 2 techniques was 10% for both periods. Differences between the values were 5% in 49% of values during periods of stability and in 50% of values during periods with therapeutic interventions. There were poor correlations between the values during periods without (r=0.48) and with therapeutic interventions (r=0.62). Better, but still less than ideal, correlations were obtained with changes in SvO2 and ScO2 during periods without (r=0.70) and with therapeutic interventions (r=0.77). Although there is a need to develop a simple technique to monitor mixed venous oxygen saturation, the present study indicates that ScO2 monitoring was not reliable in the study patients. 相似文献
23.
Terada T Matsunaga Y Maeta H Endo K Horie S Ohta T 《Virchows Archiv : an international journal of pathology》1999,435(6):606-611
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison
syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy
and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated
carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was
present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine
carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal
elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements
were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic
antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised
World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because
the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our
knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine
carcinomas.
Received: 14 April 1999 / Accepted: 7 July 1999 相似文献
24.
The one-way mixed lymphocyte reaction (MLR) is a useful model of the graft-vs.-host (GvH) response that occurs following bone-marrow transplantation (BMT). Previous studies of the MLR have shown high levels of type-1 cytokine production, such as IL-1, IL-6, IFN-γ and TNF-, but low or undetectable levels of type-2 cytokines, such as IL-4 and IL-10. Here, through establishing optimal conditions for the examination of levels and kinetics of a more definitive panel of type-1/type-2 cytokines (IL-4, IL-5, IL-10 and IL-13, IFN-γ, TNF- and the soluble IL-4 receptor) we show that, contrary to previously published data, the human alloresponse is truly heterogeneous, resulting in abundant type-2 as well as type-1 cytokine secretion. The kinetics of cytokine levels in the MLR show surprising complexity, suggesting a well-defined regulation as the alloresponse develops over time. Furthermore, each MLR responder:stimulator combination tested produces a composite cytokine profile that is intrinsic to that particular pairing. These combination-specific cytokine responses are reproducible when tested on multiple occasions over time. These data reveal a potential clinical application for the cytokine MLR in selecting donors for BMT with the least inflammatory cytokine profile. Additional analysis of this system reveals that the bulk of cytokine measured is both allospecific and T-cell-derived, with comparatively low levels produced through an autologous mechanism. Interestingly, although most of the cytokine detected is produced by CD45RO+ ‘mature/activated’ T cells, CD45RA+ ‘naive’ T cells are responsible for transient early production of IL-4. This novel finding suggests that naive T cells themselves could regulate type-1/type-2 developmental fate through an autocrine IL-4 mechanism. 相似文献
25.
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27.
阿尔茨海默病、阿尔茨海默病混合型及血管性痴呆患者心理及行为症状的比较 总被引:4,自引:0,他引:4
目的 比较阿尔茨海默病(Alzheimer Disease,AD)、AD混合型痴呆(Mixed dementia,MD)、血管性痴呆(Vascular dementia,VD)心理和行为症状(Psychological and behavioral symptoms of dementia,PBSD)的特征。方法 AD、MD及VD患者各30名参加本研究。采用Alzheimer病行为症状评定量表(The Begavioral Pathlolgy in Alzheiner Disease Rating Scale,BEHAVE—AD)、Cohen—Masfield激惹性问卷(The Cohen Mansfield Agitation Inventory,CMAI)评定痴呆患者BPSD。结果 AD患者激惹、焦虑与恐惧发生率较高,VD患者无目的游荡发生率、严重程度较低,MD患者BPSD症状无特异性。结论 AD、VD患者BPSD症状有特异性,MD患者BPSD表现无特异性。 相似文献
28.
A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage. 相似文献
29.
Ruliang Xu 《Current Diagnostic Pathology》2007,13(6):438-455
A neoplastic proliferation of peripheral nerve sheath cells (Schwann cells, fibroblasts and perineurial cells) and ganglion cells in the colorectum may give rise to the mucosal or submucosal polyps. Depending upon the predominant cell types, these neurogenic polyps can be classified as schwannomas, granular cell tumours, neurofibromas, perineuriomas, mixed nerve sheath tumours, ganglioneuromas or paragangliomas. Morphologically, the neoplastic cells repeat or mimic the corresponding nerve sheath cells or neurons in terms of growth pattern, histology and immunoreactivity. They are uncommon, but the polyps can occur in any age group, although the vast majority of patients are adults. The polyps can be either solitary (most peripheral nerve sheath tumours) or multiple, especially if associated with systemic diseases (i.e. syndromes involving the peripheral nerve tissue). They are usually incidental findings or may be accompanied by gastrointestinal symptoms. Almost all colorectal neurogenic polyps are benign, and they rarely undergo malignant transformation unless they are part of a syndromatic manifestation. However, these polyps may cause a diagnostic problem during screening for colorectal cancer. An accurate diagnosis of these entities will help clinicians to make appropriate management decisions. 相似文献
30.
Pauwels P Dal Cin P Roumen R van den Berghe H Sciot R 《Virchows Archiv : an international journal of pathology》1999,434(2):167-171
A case of an entirely intramuscular mixed tumour occurred in an 82-year-old man, who presented with a large mass in the region
of the right triceps muscle. A lobulated tumour was seen, with plump, round epithelioid cells embedded in a chondromyxoid
stroma. Immunohistochemical examination showed strong S100 protein and pancytokeratin positivity in most of the tumour cells.
Cytogenetic analysis revealed complex clonal chromosomal changes: 47, XY, +i (2) (q10), –15, der (17)t(15;17) (q11; p12),
+r. Differential diagnosis against extraskeletal myxoid chondrosarcoma (EMC) may be problematic, particularly in an incisional
biopsy. Chromosomal analysis can be very helpful in solving this problem, since EMC shows a specific reciprocal chromosome
translocation characterised as t (9;22) (q22–31) (q11–12).
Received: 8 July 1998 / Accepted: 22 September 1998 相似文献