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61.
Osamu Uemura Takuhito Nagai Kenji Ishikura Shuichi Ito Hiroshi Hataya Yoshimitsu Gotoh Naoya Fujita Yuko Akioka Tetsuji Kaneko Masataka Honda 《Clinical and experimental nephrology》2014,18(5):718-725
Background
Renal inulin clearance is the gold standard for evaluation of kidney function, but is compromised by problems of collecting urine samples in children, especially those <6 years or with a bladder dysfunction. Therefore, we should utilize the serum cystatin C (cysC)-based estimated glomerular filtration rate (eGFR) for measuring serum cysC. The purpose of the present study is to determine the applicability of the new serum cysC-based eGFR in Japanese children and adolescents, including infants with chronic kidney disease (CKD), for evaluation of renal function.Methods
Inulin clearance and standardized serum cysC level determined by the colloidal gold immunoassay were measured in 135 pediatric CKD patients between the ages of 1 month and 18 years with no underlying disease that affects renal function except CKD, to determine serum cysC-based eGFR in Japanese children and adolescents.Results
We showed the inulin clearance by expression of 1/serum cysC in pediatric CKD patients, which resulted in the equation: inulin GFR (mL/min/1.73 m2) = 104.1 × 1/serum cysC (mg/L) ? 7.80. We also validated the cysC-based eGFR formula for Japanese adults. eGFR values obtained with the adult formula significantly underestimated GFR by approximately 8 % in children with CKD.Conclusion
We determined the new cysC-based eGFR formula is useful for clinical screening of renal function in Japanese children and adolescents, including infants. 相似文献62.
Shida Atsuo Mitsumori Norio Fujioka Shuichi Takano Yuta Fujisaki Muneharu Hashizume Ryosuke Takahashi Naoto Ishibashi Yoshio Yanaga Katsuhiko 《World journal of surgery》2018,42(3):766-772
World Journal of Surgery - We started performing sentinel node navigation surgery (SNNS) for patients with early gastric cancer (EGC) using infrared ray electronic endoscopy (IREE) with indocyanine... 相似文献
63.
Hironobu Shigaki Yoshifumi Baba Masayuki Watanabe Keisuke Miyake Asuka Murata Shiro Iwagami Takatsugu Ishimoto Masaaki Iwatsuki Naoya Yoshida Hideo Baba 《Annals of surgical oncology》2013,20(3):485-491
Background
Epidermal growth factor receptor (EGFR) signaling is one of the most promising targets for molecular-targeted therapies in esophageal squamous cell carcinoma (ESCC). Thus, the molecular diagnosis of KRAS and BRAF mutations is clinically important in therapeutic decision making. However, the frequency of KRAS and BRAF mutations in ESCCs remains inconclusive because of the limited sample sizes of previous studies (all N ≤ 80). Pyrosequencing is a nonelectrophoretic nucleotide extension sequencing technology that can be used for mutation testing.Methods
The frequency of KRAS and BRAF mutations was examined using a nonbiased database of 203 resected ESCCs and a high-throughput pyrosequencing assay.Results
The validity of the KRAS pyrosequencing method was initially demonstrated by detection of all 4 types of KRAS mutations [c.35G>T (codon 12 GGT>GTT), c.35G>A (codon 12 GGT>GAT), c.34G>T (codon 12 GGT>TGT), c.38G>A mutation (codon 13 GGC>GAC)], which had been previously diagnosed using Scorpion-ARMS technology, in 9 colon cancer tissues (9 of 9; 100 %). Similar results were demonstrated for BRAF mutational status in 3 colon cancer cell lines (HCT116, Colo201, and HT29), which were validated by Sanger dideoxy sequencing. Subsequently, the KRAS mutation was found to be extremely rare (1 of 203; 0.5 %), and the BRAF mutation was absent (0 of 203; 0 %), in the dataset of 203 ESCCs.Conclusions
These results suggest that KRAS and BRAF mutations play a limited role in the development of ESCC and that mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in ESCC.64.
Okayama J Ko S Kanehiro H Kanokogi H Hisanaga M Ohashi K Sho M Nagao M Ikeda N Kanamura T Akashi S Nakajima Y 《The Journal of surgical research》2004,120(1):102-110
BACKGROUND: Establishment of hematopoietic chimerism is the most stable strategy for donor-specific tolerance. Safer pretreatment regimens are needed for clinical application. We evaluated the efficacy of a simple protocol using cyclophosphamide (CYP) on induction of chimerism and organ transplant tolerance across major histocompatibility complex (MHC) barriers in the rat. MATERIALS AND METHODS: Bone marrow cells from BN (RT1(n)) donors were infused to LEW (RT1(l)) recipients on day 0 after a single injection of CYP at various doses on day -1. Donor-derived hematopoietic chimerism was evaluated by flowcytometry. The recipients received BN or third party (BUF) heart allografts on day 100. RESULTS: While pretreatment with 200 mg/kg of CYP induced high levels of hematopoietic chimerism, six of eight recipients died of severe graft-versus-host-disease (GVHD). CYP at dose of 150 mg/kg induced 36.5 +/- 24.1% of donor-derived chimerism on day 10, and sustained macrochimerism was seen until day 100 without GVHD. Pretreatment with 100 mg/kg of CYP resulted in only transient chimerism (4.8 +/- 5.2%) which disappeared by day 20. In the recipients with 50 mg/kg of CYP, donor bone marrow cells were rapidly rejected and no chimerism was observed. The recipients with 150 mg/kg of CYP accepted BN heart allografts (>100 days x 5), while rejecting BUF allografts by day 12 (n = 4). BN heart allografts were rejected in the recipients with 100 (MST: 57 days, n = 5) and 50 mg/kg (MST: 7 days, n = 5) of CYP. CONCLUSIONS: A single dose of CYP can induce hematopoietic chimerism across MHC-barriers. The dose of 150 mg/kg seems to be optimal to induce organ transplant tolerance without developing GVHD. 相似文献
65.
Middle ear cholesteatoma extending into the petrous apex: evaluation by CT and MR imaging 总被引:1,自引:0,他引:1
K Ishii S Takahashi K Matsumoto T Kobayashi T Ishibashi K Sakamoto T Soda 《AJNR. American journal of neuroradiology》1991,12(4):719-724
CT and MR imaging findings were reviewed in four cases of acquired cholesteatoma of the middle ear that extended medially into the petrous apex and middle cranial fossa. In one case the lesion further extended anteromedially into the sphenoid sinus. CT demonstrated the lesions as nonenhancing hypodense masses with bone destruction, extending medially from the middle ear cavity to the petrous apex region. On MR imaging, the lesion was slightly hypointense relative to brain on T1-weighted images and hyperintense on T2-weighted images. MR imaging clearly delineated the extraaxial location of the lesion and associated brain displacement. The medial extension of the cholesteatomas seems to have proceeded via a detour around the bony labyrinth into the petrous apex region by following normal pathways of temporal bone pneumatization. 相似文献
66.
Naoya Shirai Hiroyuki Yamagishi Minoru Yoshiyama Masakazu Teragaki Kaname Akioka Kazuhide Takeuchi Junichi Yoshikawa Hironobu Ochi 《Journal of nuclear medicine》2002,43(4):443-450
Assessment of reversible perfusion defects in exercise (201)Tl perfusion SPECT has low sensitivity and high specificity for detection of multivessel coronary artery disease (CAD). The goal of this study was to evaluate whether worsening of left ventricular regional wall motion assessed by an automated algorithm in exercise (201)Tl electrocardiography-gated SPECT had incremental diagnostic value over perfusion data for detection of multivessel CAD. METHODS: Two hundred one patients underwent exercise (201)Tl gated SPECT. Software that automatically analyzes left ventricular function was used to assess exercise and rest regional wall motion. Regional wall motion on initial images was compared with that on rest images, that is, delayed images for patients without reinjection images and reinjection images for patients with reinjection images. The left ventricle was divided into 9 segments, with individual segments assigned to 3 coronary territories. Worsening of wall motion was defined as worsening in any segment on initial images compared with rest images. RESULTS: Of 73 patients with multivessel CAD, 20 (27.4%) had reversible perfusion defects in multiple coronary territories, 26 (35.6%) exhibited worsening of regional wall motion in multiple territories, and 37 (50.7%) had reversible perfusion defects or worsening of regional wall motion in multiple territories. The sensitivity of the combination of reversible perfusion defect and worsening of regional wall motion was significantly higher than that of reversible perfusion defect alone for detection of multivessel CAD (50.7% vs. 27.4%, P < 0.05). The specificity of the combination of reversible perfusion defect and worsening of regional wall motion for detecting multivessel CAD did not differ from that of reversible perfusion defect alone and that of worsening of regional wall motion alone (94.5% vs. 99.2% and 97.7%, respectively, P = not statistically significant). CONCLUSION: Combined assessment of worsening of left ventricular regional wall motion by exercise and perfusion data in exercise (201)Tl gated myocardial SPECT was more sensitive, with acceptable specificity, than was assessment with perfusion data alone for detection of multivessel CAD. 相似文献
67.
Mechanism of the inhibitory action of dopamine and somatostatin on prolactin secretion from human lactotrophs in culture 总被引:2,自引:0,他引:2
In an attempt to delineate the mechanism(s) of PRL secretion from human lactotrophs, the effects of dopamine and somatostatin on PRL release from adenomatous and nonadenomatous human pituitary cells in culture was studied. High K+ and the divalent cation ionophore A23187 both elevated PRL secretion, which was blocked by dopamine and somatostatin. When the cells were incubated in low calcium medium, PRL secretion was significantly inhibited. The addition of dopamine or somatostatin to low calcium medium further decreased PRL release. The stimulatory action of ionophore A23187 on PRL release was found even in the absence of extracellular calcium. Theophylline and isobutylmethylxanthine, when added to the incubation medium, increased PRL secretion, and dopamine as well as somatostatin again inhibited PRL release induced by phosphodiesterase inhibitors. No qualitative difference in these PRL responses was found in adenomatous and nonadenomatous human lactotrophs. In prolactinoma cells obtained from three different patients, cAMP generation was correlated with hormone release. Exposure of the cells to dopamine or somatostatin resulted in a parallel decrease in intracellular cAMP content and PRL secretion. The inhibitory effect of dopamine on PRL secretion and cAMP accumulation was blocked by coincubation of the cells with haloperidol. These results suggest that an increase in cytosol calcium caused by either mobilization from intracellular calcium pools or influx from the extracellular compartment and intracellular cAMP accumulation may be involved in the mechanism of PRL secretion from human lactotrophs, and dopamine and somatostatin may influence these two messengers to suppress PRL secretion. 相似文献
68.
Study Type – Symptom prevalence (cohort) Level of Evidence 2b What's known on the subject? and What does the study add? There have been few longitudinal community‐based studies on LUTS suggestive of BPH. It is important to determine the natural history of LUTS suggestive of BPH among men in various countries because it is known that there are differences according to race. Although we previously reported a cross‐sectional community‐based survey on LUTS suggestive of BPH in Japanese men, no longitudinal data were available. The present study provides 15‐year longitudinal data on LUTS suggestive of BPH and related variables in Japanese men.
OBJECTIVE
- ? To report the natural history of benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) in Japanese men.
PATIENTS AND METHODS
- ? From 1992 to 1993, we conducted a cross‐sectional community‐based study on LUTS suggestive of BPH in Japanese men aged 40–79 years.
- ? After 15 fifteen years, a follow‐up study was conducted to determine their longitudinal changes of LUTS.
- ? Of the 319 participants taking part in the initial study, 135 participated again in the follow‐up study.
- ? We investigated International Prostate Symptom Score (IPSS), quality of life index and bother score using a questionnaire, and measured prostate volume (PV), prostate‐specific antigen (PSA) level and peak urinary flow rate (Qmax) using a method that we have employed previously.
RESULTS
- ? The change in the total IPSS during 15 years was significant (P= 0.001) and its mean (sd ) annual change was 0.11 (0.40).
- ? Although there was little change in the bother score, a significant correlation was observed between changes in the IPSS and bother score (r= 0.528, P < 0.001).
- ? For the individual IPSS and bother scores, only changes in urgency, weak stream and nocturia were significant.
- ? The changes in PV, PSA level and Qmax were significant.
- ? The change in the total IPSS did not correlate with the changes in these variables.
CONCLUSION
- ? In a 15‐year‐longitudinal community‐based study for Japanese men, we have shown that the IPSS and quality of life index deteriorated, PV and PSA level increased, and Qmax decreased.
69.
Nohmi S Yamamoto Y Mizukami H Ishibashi Y Tsuda E Maniwa K Yagihashi S Motomura S Toh S Furukawa K 《International orthopaedics》2012,36(7):1515-1522
Purpose
The anterior cruciate ligament (ACL) rarely heals spontaneously after rupture. Mesenchymal stem cells (MSCs) contribute to healing in various tissues, therefore, they may also have a key role in healing after ACL rupture. The purpose of this study was to investigate the properties of MSCs in ruptured ACLs.Methods
Human ACL samples were harvested from patients undergoing primary ACL reconstruction, and samples were classified by the number of days post rupture (phase I <21 days; phase II 21–56 days; phase III 57–139 days phase IV ≥140 days). We evaluated the characteristics of MSCs, such as colony-forming capacity, differentiation potential and cell-surface markers.Results
There was a tendency for high colony-forming capacity during phases I and II, which tended to decrease in phase III. Chondrogenic, adipogenic and osteogenic differentiation potential was maintained until phase II but decreased in phase III. Most surface-epitope expression was consistent from phase I to III: positive for CD44, CD73, CD90 and CD105; negative for CD11b, CD19, CD34, CD45 and human leukocyte antigen-D-related (HLA-DR). The presence of these surface markers proved the existence of MSCs in ruptured ACL tissue.Conclusions
Our results suggest that colony-forming and differentiation potential decrease over time. It is important to consider changes in properties of MSCs and use ACL tissue in the acute phase of rupture when biological manipulation is required. 相似文献70.
M Shimoda H Noguchi Y Fujita M Takita T Ikemoto D Chujo B Naziruddin MF Levy N Kobayashi PA Grayburn S Matsumoto 《Cell transplantation》2012,21(2-3):465-471
Porcine islets are considered to be a promising resource for xenotransplantation. However, it is difficult to isolate porcine islets because of the marked fragility and rapid dissociation. Endogenous trypsin is one of the main factors to damage islets during the isolation procedure. Recent studies have suggested that trypsin inhibitors during the preservation of pancreas or the collagenase digestion can improve the result of islet isolation. In this study, we examined whether α1-antitrypsin (Aralast?), which inhibits several endogenous proteases and has immunomodulatory properties, can protect islets from the proteases and improve the results of porcine islet isolation. Twelve porcine pancreata were divided into three groups: without Aralast group (standard, n = 5), preserved with Aralast using the ductal injection (DI) method (DI, n = 3), and with Aralast using the DI method and in the collagenase solution (DI+C, n = 4). Efficacy of islet isolation was assessed by islet yields, purity, and viability. The trypsin activity of the preservation and the digestion solution during the isolation procedure was measured. During islet isolation, the trypsin activity in DI+C group was significantly inhibited compared to the standard group, whereas DI group showed less effect than DI+C group. The average of postpurification islet equivalents (IEQ) per pancreas weight in the DI+C group was significantly higher than the standard group (standard: 3516 ± 497 IEQ/g, DI: 4607 ± 1090 IEQ/g, DI+C: 7097 ± 995 IEQ/g; p = 0.017 between standard and DI+C). In the DI+C group, stimulation index was higher than in other groups, although there was no significant difference. The presence of Aralast in both DI solution and collagenase solution markedly inhibited trypsin activity during pancreas digestion procedure and improved the porcine islet isolation. Inhibition of trypsin activity by Aralast could improve porcine islet isolation. 相似文献