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71.
Shohei Yoshida Koichi Toda Shigeru Miyagawa Yasushi Yoshikawa Hiroki Hata Daisuke Yoshioka Satoshi Kainuma Takuji Kawamura Ai Kawamura Satoshi Nakatani Yoshiki Sawa 《Artificial organs》2020,44(8):883-891
Severe aortic insufficiency (AI) after implantation of continuous-flow left ventricular-assist device (LVAD) affects device performance and outcomes. However, the mechanism for the occurrence and progression of AI has not been elucidated. We investigated the impact of nonphysiological retrograde blood flow in the aortic root on AI after LVAD implantation. Blood flow pattern was analyzed in patients with and without AI (n = 3 each) who underwent LVAD implantation, by computational fluid dynamics with patient-specific geometries, which were reproduced using electrocardiogram-gated 320-slice computed tomographic images. The total volume of retrograde blood flow during one cardiac cycle (716 ± 88 mL) was higher and the volume of slow blood flow (<0.1 cm/s) (0.16 ± 0.04 cm3) was lower in patients with AI than in those without AI (360 ± 111 mL, P = .0495, and 0.49 ± 0.08 cm3, P = .0495, respectively). No significant difference in wall shear stress on the aortic valve was observed between the groups. Patients with AI had a perpendicular anastomosis at the distal ascending aorta and the simulation in the modified anastomosis model of patients with AI showed that the retrograde blood flow pattern depended on the angle and position of anastomosis. Computational fluid dynamics revealed strong retrograde blood flow in the ascending aorta and aortic root in patients with AI after LVAD implantation. The angle and position of LVAD outflow anastomosis might impact retrograde blood flow and de novo AI after LVAD implantation. 相似文献
72.
73.
Hiroto Kayashima Ken Shirabe Rumi Matono Shohei Yoshiya Kazutoyo Morita Kenji Umeda Toru Ikegami Tomoharu Yoshizumi Yuji Soejima Yoshihiko Maehara 《Surgery today》2014,44(11):2077-2085
Purpose
To evaluate the anatomical variations in the middle hepatic vein tributaries (V5/V8) for determining the reconstruction strategy in right lobe living donor liver transplantation (LDLT).Methods
The V5/V8 variations were examined in 268 patients and were classified into three and two types, respectively. The reconstruction rate (RR), patency rate (PR) and clinical outcomes were retrospectively evaluated in 46 right lobe LDLT cases.Results
In terms of V5 variations, the RR and PR were significantly higher for type 2 than type 3 (82.6 vs. 44.4 % and 73.7 vs. 25.0 %, respectively). The alanine aminotransferase level on postoperative day (POD) 5 in the V5 patent group was significantly lower than in the occluded group (123 vs. 191 IU/dL). Regarding V8 variations, the RR and PR were significantly higher for type 1 than type 2 (44.4 vs. 17.6 % and 75.0 vs. 33.3 %, respectively). The aspartate aminotransferase level on POD 3 was significantly lower in the V8 patent group than in the occluded group (50 vs. 121 IU/dL).Conclusion
For right lobe grafts with single large V5 (type 2) or V8 (type 1) variations, reconstruction is necessary. Our new classification of the MHV tributaries is useful for determining the reconstruction strategy to use in right lobe LDLT. 相似文献74.
Daisuke Suzuki Hiroshi Ono Kazuhiko Furuta Takeshi Katayama Manabu Akahane Shohei Omokawa Yasuhito Tanaka 《Journal of orthopaedic science》2014,19(3):465-470
Purpose
To investigate radiographic criteria for scapholunate instability (SLI) in the setting of distal radius fracture (DRF) confirmed by arthroscopy.Methods
Eighty-eight wrists with DRF treated by open reduction and internal fixation and assessed for SLI arthroscopically were evaluated. The scapholunate distance (SLD) was measured by preoperative posteroanterior wrist radiography and computed tomography (CT). SLD on radiographs was measured as the distance between the scaphoid cortex and the lunate cortex at the center of the scapholunate joint. SLDs were measured at the volar end (A1), center (A2), and dorsal end (A3) of the scapholunate joint on the central CT axial slice; and at the proximal end (C1), center (C2), and distal end (C3) of the scapholunate joint on the central CT coronal slice. Wrists were divided into three groups by arthroscopic assessments: stable (normal, Geissler grade 1 or 2), G3 (Geissler grade 3), and G4 (Geissler grade 4). SLD measurements on radiographs and CTs (A1–C3) were compared among the three groups. Receiver-operating characteristic (ROC) curve analyses were performed to evaluate the abilities of SLD measurements on radiographs and CTs to identify SLI in wrists with DRF. Interobserver and intraobserver reliabilities of SLD measurements on radiographs and CTs were analyzed by intraclass correlation coefficients (ICCs).Results
SLDs of C3 differed significantly among the G3 and G4 groups, and among the stable and G4 groups. The area under the curve on ROC curve analysis was 0.855 for the SLD of C3, which was larger than that for SLD on radiographs. For C3, the intraobserver ICC was 0.832 and interobserver ICC was 0.73.Conclusions
SLD at the distal end of the scapholunate joint on the central coronal CT slice was the most appropriate measurement for discrimination of Geissler grade 4 SLI in wrists with DRF.Level of evidence
Level 2 相似文献75.
We herein report that naratriptan remarkably improved intractable migraine-like headaches in a patient with Sturge–Weber syndrome (SWS) despite his past history of cerebral infarction. In addition, lamotrigine had a prophylactic effect on his visual aura and headaches. An 18-year-old male patient with SWS had intractable migraine-like headaches every several months from the age of 3 years. His migraine-like headaches were characterized by pulsating attacks preceded by left homonymous hemianopsia, which persisted after headache disappearance. In addition, after 14 years of age, the pulsating headaches were preceded by photophobia without homonymous hemianopsia and occurred almost daily. Headache pains were not improved by acetaminophen or loxoprofen sodium hydrate. Furthermore, various prophylactic drugs were ineffective. After obtaining informed consent, naratriptan was administered. The pain severity was reduced and the duration of headache with homonymous hemianopsia was shortened from several days to several hours. Interestingly, naratriptan also shortened the duration of homonymous hemianopsia to several hours. We confirmed that his headache attacks were not epileptic seizures by ictal electroencephalography. However, 25 mg/day of lamotrigine had a prophylactic effect on the frequency of headache. Moreover, lamotrigine led to complete remission of his headache without homonymous hemianopsia. Lamotrigine may have an advantage in terms of reducing the risk of cerebrovascular disease caused by migraine-like headaches and the use of triptans. The most effective management for migraine-like headaches in patients with SWS has not been established. Lamotrigine is a potentially effective option for patients with SWS with migraine-like headaches. 相似文献
76.
Kengo Nomura Sawako Tatsumi Atsumi Miyagawa Yuji Shiozaki Shohei Sasaki Ichiro Kaneko Mikiko Ito Shinsuke Kido Hiroko Segawa Mitsue Sano Tsutomu Fukuwatari Katsumi Shibata Ken-ichi Miyamoto 《Journal of the American Society of Nephrology : JASN》2014,25(4):761-772
Marked hypophosphatemia is common after major hepatic resection, but the pathophysiologic mechanism remains unknown. We used a partial hepatectomy (PH) rat model to investigate the molecular basis of hypophosphatemia. PH rats exhibited hypophosphatemia and hyperphosphaturia. In renal and intestinal brush-border membrane vesicles isolated from PH rats, Na+-dependent phosphate (Pi) uptake decreased by 50%–60%. PH rats also exhibited significantly decreased levels of renal and intestinal Na+-dependent Pi transporter proteins (NaPi-IIa [NaPi-4], NaPi-IIb, and NaPi-IIc). Parathyroid hormone was elevated at 6 hours after PH. Hyperphosphaturia persisted, however, even after thyroparathyroidectomy in PH rats. Moreover, DNA microarray data revealed elevated levels of nicotinamide phosphoribosyltransferase (Nampt) mRNA in the kidney after PH, and Nampt protein levels and total NAD concentration increased significantly in the proximal tubules. PH rats also exhibited markedly increased levels of the Nampt substrate, urinary nicotinamide (NAM), and NAM catabolites. In vitro analyses using opossum kidney cells revealed that NAM alone did not affect endogenous NaPi-4 levels. However, in cells overexpressing Nampt, the addition of NAM led to a marked decrease in cell surface expression of NaPi-4 that was blocked by treatment with FK866, a specific Nampt inhibitor. Furthermore, FK866-treated mice showed elevated renal Pi reabsorption and hypophosphaturia. These findings indicate that hepatectomy-induced hypophosphatemia is due to abnormal NAM metabolism, including Nampt activation in renal proximal tubular cells.Inorganic phosphate (Pi) absorption in the renal proximal tubules and small intestine is important for Pi homeostasis.1 The Na+-dependent Pi (Na/Pi) transport system includes type IIa and type IIc Na/Pi transporters, which are localized in the apical membrane of the proximal tubular cells, and type IIb Na/Pi transporters, which are localized in the apical membrane of the intestinal epithelial cells.1,2 Pi (re)absorption is regulated by the dietary Pi content, parathyroid hormone (PTH), and the active metabolite of vitamin D, 1α, 25-dihydroxyvitamin D3 [1,25(OH)2D3].3 Other phosphaturic hormones, termed phosphatonins, also control renal Pi handling.4 The discovery that fibroblast growth factor (FGF) 23, the first identified phosphatonin,5 originated from osteocytes established the concept of the bone-kidney axis.6,7The incidence of liver transplantation has steadily increased and the incidence of partial hepatectomy (PH) has also consequently increased.8 Hypophosphatemia frequently occurs after liver resection.9–11 Acute hypophosphatemia causes septicemia and is associated with a poor prognosis.11,12 Acute hypophosphatemia is of considerable clinical relevance because many hepatectomized patients develop marked hypophosphatemia and, thus, large doses of Pi replacement are required to maintain metabolic homeostasis.13 Urinary Pi excretion is markedly increased in many patients. After hepatectomy, hypophosphatemia is associated with hyperphosphaturia.13For many years, the increased metabolic demand of the regenerating liver was considered the underlying pathologic mechanism of hypophosphatemia. The magnitude of Pi uptake by the recovering liver, however, cannot explain the severity of the resulting hypophosphatemia.11 Hepatectomy-induced hypophosphatemia is associated with an increased renal fractional excretion index for Pi unrelated to intact FGF23, FGF7, or secreted frizzled-related protein 4 as a phosphaturic factor,14 indicating that other factors have a role in the pathogenesis of hypophosphatemia.Nicotinamide (NAM) inhibits intestinal and renal Na/Pi transport activity in normal rats.15–17 Administration of NAM to rats produces a specific dose-dependent inhibition of Na/Pi transport across the renal brush-border membrane (BBM) and an increase in urinary Pi excretion.16,17 NAM suppresses hyperphosphatemia in hemodialysis patients.18 Nicotinamide phosphoribosyltransferase (Nampt) catalyzes the first rate-limiting step in converting NAM to NAD,19,20 which is essential for cellular metabolism, energy production, and DNA repair.20–22 Nampt exists in two known forms: intracellular Nampt (iNampt) and secreted extracellular Nampt (eNampt).23 eNampt also generates an intermediate product, nicotinamide mononucleotide (NMN).23Our findings indicate that the acceleration of NAM metabolism through Nampt function in the kidney is involved in the hepatectomy-induced hypophosphatemia in rodent models. This study also suggests that NAM metabolism through the liver-kidney axis is important in Pi homeostasis. 相似文献
77.
Masataka Sugahara Akiko Goda Mitsuru Masaki Ayumi Nakabo Shohei Fujiwara Miho Fukui Kanako Itohara Shinichi Hirotan Kazuo Komamura Masaaki Kawabata-Lee Takeshi Tsujino Tohru Masuyama 《Journal of Echocardiography》2014,12(2):68-70
An 80-year-old man visited our hospital because of dyspnea on exertion from 6 months ago. Echo Doppler study showed severe calcification in the aortic valve with restricted movement and the sigmoid septum causing obstruction at the LV outflow tract (LVOT). Considering the aortic valve area (AVA) might have been inaccurately estimated, we carried out beta-blocker stress echocardiography. The transaortic pressure gradient and AVA were respectively calculated as 52 mmHg and 0.90 cm2 before propranolol administration and as 64 mmHg and 0.86 cm2 after propranolol administration. Thus, beta-blocker stress echocardiography may provide an accurate assessment of AS if the LVOT obstruction is concomitant. 相似文献
78.
Miho Yamasaki Sachiyo Funakoshi Shohei Matsuda Tomoko Imazu Yoshiaki Takeda Teruo Murakami Yorinobu Maeda 《European journal of clinical pharmacology》2014,70(8):921-924
Purpose
Magnesium oxide (MgO), a short-term osmotic laxative, is converted into MgCl2 under acidic condition in the stomach and then Mg(HCO3)2 in the intestinal tract, where Mg(HCO3)2 induces the water exudation into the intestine. This indicates that the laxative effect of MgO could be attenuated under the suppressed gastric acid secretion. In this study, the possible interaction of MgO with gastric acid secretion inhibitors was evaluated by using electronic patient records of MgO dosage levels.Methods
Defecation was controlled with MgO alone in some patients after colon surgery (n?=?67) and after total gastric resection (n?=?4). Some other patients were treated with a combination use of MgO and H2 receptor antagonist (H2RA) (n?=?14) or proton pump inhibitor (PPI) (n?=?27). The possible drug interaction of MgO with H2RA or PPI was evaluated by comparing dosage levels of MgO used in controlling defecation.Results
In controlling defecation, the daily dosage levels of MgO in patients taking H2RA or PPI and patients with total gastric resection were significantly higher than those patients taking MgO alone after colon surgery. The ratios of good constipation control (controlled well at the dosing level of 1,000 mg MgO) in patients taking H2RA or PPI were significantly lower than that in patients treated with MgO alone. In an in vitro study, the solubility of MgO at pH 4.5 was quite low, as compared with that at pH 1.2.Conclusions
When patients received H2RA or PPI, the laxative effect of MgO is decreased possibly due to the low solubility of MgO at the higher gastric pH and less generation of MgCl2 and Mg(HCO3)2. Higher dosing level of MgO or another laxative should be used in patients taking H2RA or PPI, as well as the case of patients with total gastric resection. 相似文献79.
Chie Kitahara Shuhei Morita Shohei Kishimoto Shohei Matsuno Shinsuke Uraki Ken Takeshima Yasushi Furukawa Hidefumi Inaba Hiroshi Iwakura Hiroyuki Ariyasu Hiroto Furuta Masahiro Nishi Takashi Akamizu 《Journal of diabetes investigation.》2021,12(4):664-667
We report the first case of intraoperatively detected euglycemic diabetic ketoacidosis (DKA) associated with sodium–glucose cotransporter 2 inhibitors during thoracic surgery. A 59-year-old man had a 12-year history of type 2 diabetes mellitus treated with insulin and empagliflozin. The patient developed bacterial empyema and was initiated with antibiotics at a local hospital. Owing to the persistence of his symptoms, he was transferred to our hospital after the medication of empagliflozin the day before surgery. After overnight fasting, the patient underwent thoracoscopic debridement and intrathoracic lavage surgery. During this surgery, he was noted to have euglycemic ketosis and acidosis, and diagnosed as euglycemic DKA. Immediately after the consultation in our department, the patient underwent treatment for DKA. He awoke from anesthesia normally and showed no symptoms of DKA. DKA gradually resolved over the next 24 h. Early identification and management are critical for rapid recovery from perioperative euglycemic DKA associated with sodium–glucose cotransporter 2 inhibitors, especially during thoracic surgery. 相似文献
80.
Thalidomide-induced antiangiogenic action is mediated by ceramide through depletion of VEGF receptors, and is antagonized by sphingosine-1-phosphate 总被引:8,自引:0,他引:8 下载免费PDF全文
Thalidomide, which is clinically recognized as an efficient therapeutic agent for multiple myeloma, has been thought to exert antiangiogenic action through an unknown mechanism. We here show a novel mechanism of thalidomide-induced antiangiogenesis in zebrafish embryos. Thalidomide induces the defect of major blood vessels, which is demonstrated by their morphologic loss and confirmed by the depletion of vascular endothelial growth factor (VEGF) receptors such as neuropilin-1 and Flk-1. Transient increase of ceramide content through activation of neutral sphingomyelinase (nSMase) precedes thalidomide-induced vascular defect in the embryos. Synthetic cell permeable ceramide, N-acetylsphingosine (C2-ceramide) inhibits embryonic angiogenesis as well as thalidomide. The blockade of ceramide generation by antisense morpholino oligonucleotides for nSMase prevents thalidomide-induced ceramide generation and vascular defect. In contrast to ceramide, sphingosine-1-phosphate (S1P) inhibits nSMase-dependent ceramide generation and restores thalidomide-induced embryonic vascular defect with an increase of expression of VEGF receptors. In human umbilical vein endothelial cells (HUVECs), thalidomide-induced inhibition of cell growth, generation of ceramide through nSMase, and depletion of VEGF receptors are restored to the control levels by pretreatment with S1P. These results suggest that thalidomide-induced antiangiogenic action is regulated by the balance between ceramide and S1P signal. 相似文献