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51.
Hiyama T Tanaka S Yoshihara M Sasao S Kose K Shima H Tuncel H Ueno Y Ito M Kitadai Y Yasui W Haruma K Chayama K 《Journal of gastroenterology and hepatology》2004,19(7):756-760
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers. 相似文献
52.
53.
Dr. Kazutomo Inoue MD Tamotsu Kawano MD Koichi Shima MD Teruji Kim MD Takashi Suzuki MD Takayoshi Tobe MD Masaharu Takeyama PhD Haruaki Yajima PhD 《Digestive diseases and sciences》1983,28(8):724-732
This study was undertaken to determine the effect of synthetic chicken vasoactive intestinal peptide (VIP) on pancreatic blood flow, exocrine and endocrine secretions of the pancreas, and biliary secretion in dogs. The effect of synthetic chicken VIP on pancreatic blood flow and systemic arterial pressure was identical to that of natural chicken VIP in dogs. The present study demonstrated that synthetic chicken VIP induces significant increases in pancreatic blood flow, pancreaticobiliary secretion, and blood levels of insulin and glucose in dogs. Both the volume of pancreatic juice and blood levels of insulin were increased in consonance with the increase of pancreatic blood flow. This study suggests that the stimulatory effects of synthetic chicken VIP on exocrine and endocrine secretions of the pancreas may be related to the increased pancreatic blood flow elicited by synthetic chicken VIP. 相似文献
54.
Malignant serous cystic neoplasm of the pancreas: report of a case and review of the literature 总被引:4,自引:0,他引:4
Matsumoto T Hirano S Yada K Shibata K Sasaki A Kamimura T Ohta M Kitano S Kashima K 《Journal of clinical gastroenterology》2005,39(3):253-256
BACKGROUND: In general, serous cystic neoplasms of the pancreas are thought to be benign. Malignant serous cystic neoplasm of the pancreas is a rare clinical entity. CASE REPORT: We report the case of an 87-year-old woman with a serous microcystic neoplasm in the tail of the pancreas that behaved in a malignant fashion. The neoplasm had also invaded the colonic mesentery and splenic hilum. The pancreatic lesion was diagnosed as a large malignant serous cystic neoplasm, and the patient underwent distal pancreatectomy with splenectomy and segmental colectomy. The resected specimen contained a large tumor, 12 x 9 x 8 cm, which occupied the body and tail of the pancreas. Histologically, the tumor was indistinguishable from serous cystadenoma. However, the tumor had invaded surrounding tissues including the splenic vein, and there were splenic invasion and a regional lymph node metastasis. The postoperative course was uneventful. DISCUSSION: There are few reported cases of malignant serous cystic neoplasm, in which malignancy was histologically confirmed in the resected specimen. There are no reports of a negative outcome with complete resection of the tumor. Surgical treatment should be considered for serous cystic neoplasms, especially large ones, because of the malignant potential. 相似文献
55.
Yoshida T Matsumoto T Morii Y Aramaki M Matsumoto S Mori H Kitano S 《Hepato-gastroenterology》2005,52(61):8-12
BACKGROUND/AIMS: Preoperative information on arterial anatomy in the peripancreatic and hepatic areas is valuable to any surgeon performing pancreatoduodenectomy. METHODOLOGY: Between 1994 and 1998, 49 patients with periampullary cancer (31 distal bile duct and 18 ampullary tumors) underwent visceral angiography and radical pancreatoduodenectomy with lymphadenectomy. Surgically "significant" arterial variations and their effects on operative management and results were examined retrospectively. RESULTS: Arterial variations were found in 18 patients (37%); 15 (31%) were "significant" and 3 (6%) were "nonsignificant." All 15 patients with "significant" variants required specific type of various preservations of the hepatic arterial system. Intraoperative blood loss, transfused blood units, and operation time were greater in patients with "significant" variations than in patients without (P<0.05). Histopathologic diagnosis, tumor staging, morbidity, and mortality did not differ between the 2 groups. The 5-year survival was 33% for patients with "significant" variations and 63% for patients without (P<0.05). CONCLUSIONS: Information on arterial anatomy in the peripancreatic and hepatic areas is necessary for preoperative evaluation in patients requiring radical pancreatoduodenectomy. Presence of "significant" arterial variations may be considered as one of the negative prognostic factors in patients with periampullary cancer. 相似文献
56.
57.
Shima Farahani Navid Eshghi Abolfazl Abbasi Fereshteh Karimi Ebadallah Shiri Malekabad 《Toxin reviews》2015,34(2):96-100
Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms. 相似文献
58.
Protein C activation in NIDDM patients 总被引:6,自引:0,他引:6
E. C. Gabazza H. Takeya H. Deguchi Y. Sumida O. Taguchi K. Murata K. Nakatani Y. Yano M. Mohri M. Sata T. Shima J. Nishioka K. Suzuki 《Diabetologia》1996,39(12):1455-1461
Summary Enhanced activation of the clotting system has been recently implicated in the pathogenesis of vascular complications in
patients with diabetes mellitus. Abnormalities of the anticoagulant system may constitute a potential trigger factor for the
haemostatic activation observed in diabetic subjects. The current study aimed to evaluate anticoagulant activity in diabetic
patients by assessing the plasma levels of activated protein C-protein C inhibitor complex; and by measuring the anticoagulant
response to exogenous thrombomodulin. This study comprised 61 patients (34 men, 27 women) with non-insulin-dependent diabetes
mellitus (NIDDM) of whom 22 showed microalbuminuria and 39 normoalbuminuria. Data obtained in 31 non-obese and non-diabetic
subjects were available for comparison. The plasma levels of fibrinogen (p < 0.02), prothrombin fragment 1 + 2 (p < 0.05), fibrin monomer (p < 0.0001), protein C antigen (p < 0.005), total protein S antigen (p < 0.02), soluble thrombomodulin (p < 0.005) and soluble E-selectin (p < 0.005) were significantly higher in diabetic patients than in healthy subjects. The plasma level of activated protein C-protein
C inhibitor complex (7.4 ± 3.8 vs 3.0 ± 0.4 pmol/l) was significantly higher (p < 0.0001) and the anticoagulant response to exogenous thrombomodulin (23.4 ± 2.6 vs 35.3 ± 3.0 ng/ml) was markedly lower
(p = 0.005) in all diabetic patients than in healthy subjects. Cases with microalbuminuria presented low plasma levels of activated
protein C-protein C inhibitor complex (5.5 ± 0.6 vs 8.6 ± 0.7 pmol/l, p < 0.05) and significantly decreased values of the anticoagulant response to exogenous thrombomodulin (16.5 ± 2.9 vs 23.4
± 2.6 %, p = 0.03) as compared to those with normoalbuminuria. The present study suggests that the hyper-coagulable state in NIDDM is
associated with an increased activation of protein C but with a poor plasma reactivity to the anticoagulant effect of thrombomodulin.
[Diabetologia (1996) 39: 1455–1461]
Received: 27 February 1996 and in revised form: 3 June 1996 相似文献
59.
Marked increases of two kinds of two-exon-skipped albumin mRNAs with aging and their further increase by treatment with 3''-methyl-4-dimethylaminoazobenzene in Nagase analbuminemic rats. 总被引:2,自引:1,他引:2 下载免费PDF全文
T Kaneko H Shima H Esumi M Ochiai S Nagase T Sugimura M Nagao 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(7):2707-2711
Nagase analbuminemic rats (NARs) have a 7-base-pair deletion at the 5' splice site of the HI intron of the albumin gene. The level of immunohistochemically albumin-positive hepatocytes is about 1 per 10(5) cells in neonatal NARs, increases with age, and further increases with chronic oral treatment with 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB). The mechanisms involved in the increase in albumin-positive hepatocytes during aging of NARs and their treatment with 3'-MeDAB were analyzed. NARs were found to have four species of albumin mRNA: intact mRNA and those lacking the regions corresponding to exon H, exon G-H, and exon H-I. In 4-week-old NARs, the level of intact albumin mRNA was about 1/4000 of that in normal rats and mRNA lacking the exon H sequence was the major species. In aged and 3'-MeDAB-treated aged NARs, all four species of mRNA increased and the relative proportion of mRNAs lacking two exon sequences to mRNAs lacking one exon sequence was greatly increased, suggesting that aging is associated with changes of the splicing pattern and that 3'-MeDAB treatment enhanced these changes. In aged NARs and 3'-MeDAB-treated aged NARs, there was an increase in the amount of aberrant 60-kDa albumin. The 60-kDa protein could be a translation product of mRNAs lacking two exons, the amount of which increases in aged NARs and 3'-MeDAB-treated NARs. 相似文献
60.
J. Fu H. Ikegami Y. Kawaguchi T. Fujisawa Y. Kawabata Y. Hamada H. Ueda M. Shintani K. Nojima N. Babaya Q.-J. Shen Y. Uchigata T. Urakami Y. Omori K. Shima T. Ogihara 《Diabetologia》1998,41(2):228-232
Summary An insulin-dependent diabetes mellitus (IDDM)-susceptibility gene (IDDM13) has recently been mapped to a region of distal chromosome 2q, which is syntenic to the region of mouse chromosome 1 containing
a murine susceptibility gene for IDDM, Idd5. To determine the contribution of this region to IDDM disease susceptibility further and to narrow the region for positional
cloning of susceptibility genes, we have studied the association of distal chromosome 2q with IDDM in the genetically distinct
Japanese population. A 137 mobility unit (mu) allele at D2S137 locus was significantly associated with IDDM (odds ratio 1.92, p = 0.0016). Other markers, D2S301 and D2S143, located in the same region were not associated with IDDM, indicating that IDDM13 is in linkage disequilibrium with D2S137, but not with D2S301 or D2S143. The association of D2S137 with IDDM was observed in patients lacking one of two high risk HLA alleles, DQB1
*
0303 and DQB1
*
0401, but not in patients with either of these alleles. The frequency of high risk HLA alleles was significantly lower in patients
with the susceptible allele at D2S137, suggesting that IDDM13 contributes to IDDM susceptibility in subjects without high risk genotypes at IDDM1. Demonstration of allelic association of D2S137 with IDDM localizes IDDM13 in the close vicinity (< 2 centiMorgans) of D2S137, greatly facilitating fine structure mapping and positional cloning of IDDM13. [Diabetologia (1998) 41: 228–232]
Received: 27 March 1997 and in revised form: 3 October 1997 相似文献