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51.
Kazushiro Tsuji Kouji Narahara Kiyoshi Kikkawa Masae Murakami Yuji Yokoyama Shinsuke Ninomiya Yoshiki Seino 《American journal of medical genetics. Part A》1994,49(1):98-102
Craniosynostosis (CRS) is frequently seen in the del(7p) syndrome, and the gene for this cranial anomaly (CRS1) has been assigned to 7p21. We present a 3-year-old boy with CRS involving the sagittal and coronal sutures, who had a de novo and apparently balanced translocation, t(6;7)(q16.2;p15.3). Southern blot analysis of several loci on 7p14 → pter showed that the patient was heterozygous for HOX1I and IL6, possibly homozygous for D7S149, but hemizygous for D7S135 with a loss of the paternal allele. These findings suggest the localization of a candidate gene for CRS1 to be on 7p15.3 in the close proximity to the D7S135 locus. © 1994 Wiley-Liss, Inc. 相似文献
52.
Azuma A Koyama T Mikami Y Tamai K Fujimoto K Morisawa N Nagano F Yoshioka S Togashi K 《Pediatric radiology》2008,38(8):898-901
We present a case of Sertoli-Leydig cell tumour of the ovary in a 14-year-old girl who presented with abdominal distension. Ultrasonography showed a multilocular cystic lesion filled with finely echogenic fluid. Contrast-enhanced CT demonstrated a huge multilocular cystic mass with thickened septa. At MR imaging, the capsule of the cyst was focally thickened, showing intermediate signal intensity on T2-W images. Although extensive cyst formation of Sertoli-Leydig cell tumour is rare, this tumour should be considered in the differential diagnosis of a multilocular cystic ovarian tumour in a young female. 相似文献
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54.
Akitaka Nonomura Yuji Mizukami Fujitsugu Matsubara Naoko Kono Yasuni Nakanuma 《Pathology international》1989,39(5):328-335
A case of pancreatic tumor with features of both duct and islet cell components was found incidentally at autopsy in a 76 year old male who had died of intrahepatic cholan-giocarcinoma. The tumor, measuring about l.0cm in diameter, was located in the pancreatic tail. The tumor was composed of two distinct cell populations, islet cells and duct cells. Immunocytochemically, nearly all of the former cells were positive for insulin but negative for cytokeratin, carcinoembryonic antigen (CEA) and mucin, while the latter were positive for cytokeratin, CEA and mucin but negative for insulin. Additionally, a majority of the tumor cells that had formed islet-like structures were positive for neuron specific enolase (NSE), whereas NSE-positive cells were found only rarely in duct components. Electron microscopy confirmed the presence of two cell populations. Simultaneous occurrence of duct and islet cell components in a single pancreatic tumor indicates an intimate histogenetic relationship between pancreatic endocrine and duct cells. Acta Pathol Jpn 39: 328 335, 1989. 相似文献
55.
Toshio Nakatani Shigenori Tanaka Shigeki Mizukami 《Clinical anatomy (New York, N.Y.)》1998,11(3):209-212
Bilateral four-headed biceps brachii muscles were observed in the dissected cadaver of a 95-year-old Japanese woman. The third head on both sides originated from the humerus at the insertion of the coracobrachialis and inserted into the distal part of the biceps brachii and the proximal part of the common biceps tendon on the ipsilateral side. The fourth head on both sides arose from a thin fibrous origin from the intertubercular sulcus and the insertion of the pectoralis major, and inserted into the confluence of the biceps brachii and the third head. This anomaly is relatively rare. Moreover, the left third head gave off a muscle slip into the posterior fascia of the pronator teres, forming a tunnel. The median nerve and the brachial artery passed through the tunnel, where the nerve and artery seemed to be compressed. The possible production of clinical symptoms, given the anatomy, is discussed. Clin. Anat. 11:209–212, 1998. © 1998 Wiley-Liss, Inc. 相似文献
56.
Accelerated Loss of Islet β Cells in Sucrose-Fed Goto-Kakizaki Rats, a Genetic Model of Non-Insulin-Dependent Diabetes Mellitus 下载免费PDF全文
Motoi Koyama Ryu-ichi Wada Hiroyasu Sakuraba Hiroki Mizukami Soroku Yagihashi 《The American journal of pathology》1998,153(2):537-545
The Goto-Kakizaki (GK) rat is a spontaneously diabetic animal model of non-insulin-dependent diabetes mellitus, which is characterized by progressive loss of β cells in the pancreatic islets with fibrosis. In the present study, we examined the effects of sucrose feeding on the islet pathology in this model. Six-week-old GK rats were fed with 30% sucrose for 6 weeks to induce severe hyperglycemia, and their condition was compared with that of nontreated rats. Age-matched normal Wistar rats were also given sucrose for the same periods and used for comparison. The sucrose-treated GK rats showed elevated blood glucose levels on oral glucose tolerance tests at 60 minutes and 120 minutes, representing 123% and 127% of values in untreated GK rats, respectively. At the end of the study, the mean β-cell volume density in GK rats was 50% less than that in untreated Wistar rats. Sucrose feeding further reduced the volume densities of β cells to only 50% of the levels of age-matched GK rats. Apoptotic cells were found in islet β cells only in GK rats fed sucrose (mean 0.067%). There appeared to be more islets that immunohistochemically stained strongly positive with 8-hydroxy-deoxyguanosine as a marker of oxidative damage of DNA in GK rats fed sucrose compared with those not given sucrose. GK rats not fed sucrose showed significantly lower proliferative activity of β cells measured by 5-bromo-2′-deoxyuridine uptake and intensified expression of Bcl-2 immunoreactivities at 6 weeks of age compared with those in age-matched Wistar rats. These two indices were reduced in both GK and Wistar rats with increasing age and were not affected by sucrose feeding in either group. The present study thus indicated that sucrose feeding promoted the apoptosis of β cells in GK rats through increased oxidative stress without altering their proliferative activity. 相似文献
57.
Cell type-selective expression of green fluorescent protein and the calcium indicating protein,yellow cameleon,in rat cortical primary cultures 总被引:9,自引:0,他引:9
A cell type-specific green fluorescent protein (GFP) expression system in rat cortical primary cultures has been developed for the fluorescence labeling of brain cells. Lipid-mediated transfection (lipofection) was employed, allowing the establishment of a convenient efficient system for the analysis of individual cells. To achieve cell type-specific labeling, GFP expression vectors containing the rat neuron-specific enolase (NSE) gene promoter, human glial fibril acidic protein (GFAP) gene promoter, human elongation factor (EF-1alpha) gene promoter, or human cytomegalovirus (CMV) immediate early promoter were constructed, and their specificities examined. Vectors containing the CMV or GFAP promoter resulted primarily in GFP expression in astrocytes, while those containing the EF1-alpha or NSE promoter resulted primarily in GFP expression in neurons. This labeling system was applied to the morphological analysis of living neurons and to cell type-selective calcium imaging. Confocal microscopy revealed that individual GFP-expressing neurons had processes, which were longer than 500 microm and bore spine-like protrusions. A calcium-indicating GFP variant, yellow cameleon (YC2.1), was expressed in the same system, and cell type-selective calcium imaging performed. On pharmacological stimulation, YC2.1-expressing neurons responded to depolarizing stimuli, but not to the metabotropic glutamate receptor agonist, trans-(1S,3R)-1-amino-1,3-cyclopentanedicarboxylic acid (tACPD), while astrocytes responded only to tACPD. 相似文献
58.
59.
Hideaki Sogawa Kiyotaka Horino Fukumi Nakamura Tooru Kudoh Kazuhiko Oyanagi Toyoshige Yamanouchi Ryoji Minami Tooru Nakao Akira Watanabe Yoshiki Matsuura 《European journal of pediatrics》1978,128(4):235-240
Clinical, biochemical, and electron microscopic studies are pesented in two brothers with Niemann-Pick disease. The clinical features include hepatosplenomegaly and mental retardation without any other neurological signs. Roentgenograms of the chest showed bilateral diffuse reticular infiltration. The amounts of sphingomyelin and cholesterol in liver were increased, and sphingomyelinase activities in both liver and skin fibroblasts were markedly reduced in Case 1. Numerous foam cells and myelin figures were observed in the liver, kidneys, bone marrow, and lymph nodes on electron microscopical examination. These cases were regarded as a variant of Niemann-Pick disease from our investigations as they have mental retardation as an exceptional symptom when they are diagnosed as type B. 相似文献
60.
Toxicity of dichloropropanols 总被引:1,自引:0,他引:1
A rare outbreak of acute hepatic damage in workers exposed to dichloropropanols was reported in 1992. As there are no detailed reports of dichloropropanols (DCPs) toxicity and its mechanism, we reviewed the toxicity of dichloropropanols using our results. 1) A marked elevation of serum AST and ALT with massive necrosis of the liver was noted in the 1/2 x, the 1 x and 2 x LD50 (0.149 mg/kg) of 1, 3-dichloro-2-propanol(DC 2 P). Hepatic malondialdehyde level was significantly increased, and associated with a decrease in liver glutathione S-transferase activity and reduced glutathione content. It is suggested that the free radical is associated with DCPs. 2) A reduction of leukocytes, platelets and fibrinogen, and prolonged prothrombin time were observed in the 1 x LD50 of DC 2 P. 3) In the CA1 area of the hippocampus, inhibition of population spikes was reduced by the 1 x LD50 of DC 2 P. This research was completed with the assistance of several other papers concerning dichloropropanols toxicity. 相似文献