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排序方式: 共有630条查询结果,搜索用时 31 毫秒
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Sanjay Kakar Kenneth P Batts John J Poterucha Lawrence J Burgart 《Modern pathology》2004,17(7):874-878
Impairment of venous outflow from the liver manifests as zone 3 sinusoidal dilatation and congestion (SDC) in liver biopsy. The spectrum of histologic changes in portal tracts has not been described. We studied liver biopsies from 34 patients with a confirmed diagnosis of venous outflow impairment (VOI). Liver transplant recipients and biopsies with cirrhosis and hepatic neoplasms were excluded. Clinical records were reviewed for laboratory tests and radiographic findings. In all, 19 patients had right heart disease, 13 had classic Budd-Chiari syndrome and two had veno-occlusive disease. Liver chemistry tests showed elevated liver transaminases (n=21; 61.8%), elevated alkaline phosphatase (n=31; 91.2%) and GGT (all 13 cases tested). The elevation in ALT and AST was mild (below 200 U/l in all cases), while alkaline phosphatase (ALP) was elevated above 500 U/l in nine (26.5%) patients and above 1000 U/l in three cases. On biopsy, all cases showed SDC. The portal tracts showed (a) portal expansion with bile ductular proliferation (n=16; 47.1%) accompanied by lymphoplasmacytic infiltrate (n=10), lymphocytic cholangitis (n=3) and portal or periportal fibrosis (n=11), (b) Portal and/or periportal fibrosis without ductular proliferation (n=3; 8.8%) or (c) Normal portal tracts (n=15; 44.1%). The combination of elevated ALP and bile ductular changes on biopsy suggested chronic bile duct disease. Ultrasound/CT scan evaluation of bile ducts in 26 patients showed no biliary tree abnormality. Antimitochondrial antibody testing in eight cases also yielded negative results. In conclusion, bile ductular proliferation, portal inflammation and portal-based fibrosis are commonly seen in liver biopsies of patients with VOI even in the absence of bile duct disease. These changes are often accompanied by elevated ALP and GGT and can lead to the suspicion of chronic biliary disease. In the absence of demonstrable abnormalities in the biliary tree, these changes can be attributed to venous outflow impairment. 相似文献
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K. Skradski M. E. Reid PhD M. Mount H.F. Polesky L. Sausais M. Yacob and R. Batts 《Vox sanguinis》1994,66(1):68-71
A discrepancy in duplicate anti-K1 typing in a parentage case led to the discovery of an unusual K1 blood group antigen. Red blood cells from the propositus (JC) express a rare variant of the K1 antigen that is detectable by only 8 of 72 sera containing anti-K1. Absorption and elution studies using reactive anti-K1 confirmed the presence of a K1 antigen. Nonreactive anti-K1 was not absorbed by or eluted from JC's red blood cells. Red cells from 3 of the propositus's siblings also had the variant K1 antigen. The variant antigen exhibited qualitative as well as quantitative differences as compared to normal K1, and we have named it K1var. 相似文献
6.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
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Chang HJ Batts KP Lloyd RV Sebo TJ Thompson GB Lohse CM Pankratz SV 《Endocrine pathology》2000,11(3):229-241
Nonfunctioning islet cell tumors or pancreatic endocrine tumors are the most common type of malignant islet cell tumor. Although
previously detected usually at an advanced stage because of mass effect, the early detection rate of small localized disease
has been increasing. To date it has been difficult to predict the clinical behavior in localized regional nonfunctioning tumors.
To investigate potential markers predicting malignancy and poor prognosis in nonfunctioning pancreatic endocrine tumors, we
analyzed the expression of Ki-67, topoisomerase IIα (Topollα), and p27, as well as a variety of clinicopathologic parameters
in 76 cases of nonfunctioning islet cell tumors (23 benign cases and 53 malignant cases). Ki-67, Topollα, and p27 labeling
indices were significantly different between benign and malignant tumors. Expression of Ki-67, Topollα, and p27 were associated
with survival in patients with a malignant tumor in a univariate setting. However, only p27 and Topollα were jointly associated
with survival in multivariate analysis. Immunohistochemical staining for p27, Topollα, and Ki-67 can be helpful in the diagnosis
of nonfunctioning pancreatic endocrine tumor. Analysis of p27 and Topollα may also have potential utility as prognostic factors
for malignant tumors. 相似文献
10.
Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献