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991.
Pancreatic tuberculosis 总被引:6,自引:0,他引:6
Sanabe N Ikematsu Y Nishiwaki Y Kida H Murohisa G Ozawa T Hasegawa S Okawada T Toritsuka T Waki S 《Journal of Hepato-Biliary-Pancreatic Surgery》2002,9(4):515-518
A 63-year-old Japanese man visited our institute with fever of unknown origin. Findings on preoperative imaging modalities were consistent with pancreatic carcinoma, but a positive tuberculin skin test indicated tuberculosis infection. Negative results for MycobacteriumDNA polymerase chain reaction from sputum and bone-marrow aspiration biopsy specimens ruled out pulmonary and miliary tuberculosis, respectively. Positron emission tomography (PET) with 2-[fluorine-18]-fluoro-2-deoxy- d-glucose (FDG) showed multiple labeled spots within the pancreas body and chest. Distal pancreatectomy was performed with a diagnosis of suspected pancreatic carcinoma, but the histological and microbiological diagnosis was Mycobacterium infection. A rare case of pancreatic tuberculosis evaluated by FDG PET is reported and discussed herein. 相似文献
992.
Hepatocyte-based biological therapies are increasingly envisioned for temporary support in acute liver failure and provision of specific-liver functions in liver-based metabolic deficiency. One of the hurdles to develop such therapies is severe shortage of human livers for hepatocyte isolation. To address the issue, we have focused on reversible immortalization of human hepatocytes. Such technology can allow rapid preparation of functional and uniform human hepatocytes. Here we present our strategy to construct transplantable human hepatocyte cell lines. 相似文献
993.
The aim of this study is to evaluate the biomechanical effects of multilevel foraminotomy and foraminotomy with double-door laminoplasty compared with foraminotomy with laminectomy. Using fresh human cadaveric specimens (C2-T1), sequential injuries were created in the following order: intact, bilateral foraminotomies (C3-C4, C4-C5, C5-C6), laminoplasty (C3-C6) using hydroxyapatite spacer, removal of the spacers, and laminectomy. Changes in the rotations of each vertebra in each injury status were measured in six loading modes: flexion, extension, right and left lateral bending, and right and left axial rotation. Foraminotomy alone and following laminoplasty showed no significant differences in motion compared with intact except in axial rotation. After removal of the spacers and following laminectomy, the motion increased significantly in flexion and axial rotation. The ranges of initial slack showed similar trends when compared with the results at maximum load. Clinical implications of these observations are presented. 相似文献
994.
Endoscopic findings in chronic subdural hematoma 总被引:10,自引:0,他引:10
Shiomi N Hashimoto N Takeuchi H Yamanaka T Nakagawa N Mineura K 《No shinkei geka. Neurological surgery》2002,30(7):717-722
On the genesis of chronic subdural hematoma (CSH), it is one of the possible explanations that a head injury triggers uncertain cause off for the formation of the hematoma membrane, where the bleeding occurs to form and enlarge the hematoma. Although some reports on the staging classification based on computed tomography (CT) findings are available the natural course or history of the hematoma formation is not yet known. As previously reported, we have been using an endoscopically guided method in which a drainage tube is placed in the most frontal area of the cavity so as to evacuate the residual air efficiently. In this study, we analyzed the endoscopic findings in hematoma cavities and compared them with the clinical data, focusing on the post-trauma interval and recurrence of the hematoma. Between January 1999 and October 2000, we had an opportunity to observe the inner aspect of 60 hematomas in 48 patients. A trabecular structure was found in 39 hematoma cavities (65%), whereas apparent clot formation was observed in 18 cavities (30%). Septum formation leading to a multi-loculated hematoma was observed in 10 cavities (17%). Twenty-six patients with 32 hematomas with the obvious history of head injury were classified into 4 groups according to the post-traumatic interval to the surgery, which are stage I; less than 30 days, stage II; 31 to 60 days, stage III; 61 to 90 days and stage IV; more than 91 days. Clot formation and a trabecular structure were frequently seen in stages II and III. Clot formation was statistically and significantly seen in the recurrent group. The results suggest that CSHs increase in size in stages II and III, when clot formation and a trabecular structure are frequently observed. Endoscopic observation of hematomas may assist to know hematomas, and clot formation may be a warning of hematoma recurrence. 相似文献
995.
Umezu H Kuwata K Ebe Y Yamamoto T Naito M Yamato Y Ishiyama T Tsuchida M Okuizumi M Ishikawa H Koizumi N 《Pathology international》2002,52(5-6):416-422
The case of a 70-year-old man with a hitherto undescribed pleural mesothelioma is reported. The tumor was localized in the left lung apex and had invaded the parietal pleura. Histologically, the tumor was characterized by a proliferation of epithelioid cells and the formation of microcysts. The tumor cells were positive for calretinin and vimentin, and possessed abundant microvilli, indicating a mesothelial cell origin for the tumor. A high Ki-67 index and mitotic index, and the recurrence of the tumor after surgery, indicated malignancy. Based on the evidence, we propose that the tumor is a microcystic variant of a localized malignant mesothelioma. 相似文献
996.
Shimohata N Chiba S Saikawa N Ito K Akiyama Y 《Genes to cells : devoted to molecular & cellular mechanisms》2002,7(7):653-662
BACKGROUND: The abnormal accumulation of misfolded proteins outside the plasma (cytoplasmic or inner) membrane up-regulates the synthesis of a class of envelope-localized catalysts of protein folding and degradation. The pathway for this transmembrane signalling is mediated by the CpxR-CpxA two-component phospho-relay mechanism. RESULTS: We now show that an abnormality in the plasma membrane proteins, due either to the impairment of FtsH, a protease acting against integral membrane proteins, or to the overproduction of a substrate membrane protein of FtsH, activates this stress response pathway. Under such conditions, the cpxR gene function becomes essential for cell growth. We further show that the expression of a putative protease, HtpX, in the plasma membrane, is under the control of CpxR. Synthetic growth inhibition was observed when the ftsH and htpX disruption mutations had been combined, suggesting that these gene products have some complementary or overlapping proteolytic functions. Topology analyses indicated that the metalloproteinase active site of HtpX is located on the cytosolic side of the membrane. CONCLUSIONS: Taken together, these results suggest that the Cpx "extracytoplasmic" stress response system controls the quality of the plasma membrane, even on its cytoplasmic side. 相似文献
997.
Masahiro Tojo M.D. Tadao Oikawa M.D. Yoshiyuki Morikawa M.D. Naoya Yamashita M.D. Satoshi Iwata M.D. Yoshitake Satoh M.D. Juhei Hanada M.D. Ryuichiro Tanaka 《Pediatrics international》1987,29(1):160-167
We studied the effects of Bifidobacterium breve on Campylobacter enteritis. Patients with Campylobacter enteritis were divided into three groups (I. Erythromycin recipients; II. B. breve recipients; III. control) and studied with regard to the duration of diarrhea and carriage of Campylobacter jejuni in the stools. Additional studies were performed to observe the effects of B. breve on fecal flora. The results showed that there were no significant differences in the duration of diarrhea among the three groups. Comparison of the duration of C. jejuni carriage in the stools was as follows: KIKIII (P<0.01). Microbiological study of fecal flora demonstrated that the number of bifidobacterium was decreased in Campylobacter enteritis compared to the control, and an increase in the number of bifidobacterium could be recognized after the administration of B. breve. B. breve was useful in eradicating C. jejuni from the stools and restoring the normal intestinal flora in Campylobacter enteritis, although if was not effective in shortening the duration of diarrhea. 相似文献
998.
Naoya Takahashi 《Annals of nuclear medicine》1994,8(4):253-258
A more accurate quantitative method for the measurement of regional cerebral blood flow (rCBF) with the microsphere model and N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) and ring-type single-photon emission computed tomography (SPECT) was developed. Continuous withdrawal of arterial blood was carried out for 5 minutes after the injection. Static SPECT data were acquired from 25 min to 55 min. To estimate reconstructed images at 5 min, total brain count collections and one minute SPECT studies were performed at 5, 20, and 60 min. Quantitative values for rCBF were calculated from short time SPECT images at 5 min (rCBF), static SPECT images corrected by total brain counts (rCBFct) and those corrected by reconstructed counts on short time SPECT images (rCBFCb). Practically, rCBFCb is calculated by using reconstructed counts of regions of interest placed in the same position as static SPECT and short time SPECT at 5, 20, 60 min. Although there was good correlation between rCBF and rCBFCt (r = 0.69), rCBFct tended to be underestimated in high flow areas and overestimated in low flow areas. A better correlation was observed between rCBF and rCBFCb (r = 0.92). The overestimation and underestimation observed in rCBFCt was considered to be due to the correction method with a total cerebral time activity curve, because the kinetic behavior of123I-IMP was different in each region. 相似文献
999.
Functional assessment of ABCG2 (BCRP) gene polymorphisms to protein expression in human placenta. 总被引:11,自引:0,他引:11
1000.
Naoya Sakamoto Nobuyuki Enomoto Masayuki Kurosaki Yasuhiro Asahina Shinya Maekawa Kazuhiko Koizumi Ikuo Sakuma Takeshi Murakami Fumiaki Marumo Chifumi Sato 《Journal of medical virology》1995,46(1):7-11
Nucleotide sequences of the hypervariable region of hepatitis C virus genomes obtained from plasma change rapidly during the course of in fection and are believed to play a part in immunological escape and consequently in the development of persistent infection. It is not known, however, whether these changes also occur in the liver. To clarify this aspect, RNA was extracted from the plasma and liver tissue of eight patients with chronic hepatitis C. After cDNA synthesis, DNA fragments that included the hypervariable region were amplified by the polymerase chain reaction. Consensus nucleotide sequences were determined directly from the polymerase chain reaction products by the dideoxy chain termination method. The diversity of the hypervariable region was analyzed further by the polymerase chain reaction-single strand conformation polymorphism analysis. Consensus nucleotide sequences of the hypervariable region were identical between the plasma and the liver in each patient. The polymerase chain reaction-single strand conformation polymorphism analysis showed multiple DNA bands that represented different hypervariable region sequences. Comparison of the single strand conformation polymorphism patterns revealed that the number, the mobility, and the density of bands were the same between the plasma and the liver. It is concluded that the population and the diversity of hepatitis C virus quasispecies as detected by the hypervariable region sequence are the same between the plasma and the liver despite rapid mutations, indicating that rapid changes in the population of hepatitis C virus quasispecies also occur in the liver. © 1995 Wiley-Liss, Inc. 相似文献