全文获取类型
收费全文 | 37702篇 |
免费 | 2774篇 |
国内免费 | 205篇 |
专业分类
耳鼻咽喉 | 297篇 |
儿科学 | 1112篇 |
妇产科学 | 732篇 |
基础医学 | 4665篇 |
口腔科学 | 650篇 |
临床医学 | 3700篇 |
内科学 | 8338篇 |
皮肤病学 | 584篇 |
神经病学 | 3848篇 |
特种医学 | 1165篇 |
外国民族医学 | 1篇 |
外科学 | 5286篇 |
综合类 | 825篇 |
一般理论 | 30篇 |
预防医学 | 3096篇 |
眼科学 | 750篇 |
药学 | 2711篇 |
4篇 | |
中国医学 | 186篇 |
肿瘤学 | 2701篇 |
出版年
2023年 | 221篇 |
2022年 | 285篇 |
2021年 | 756篇 |
2020年 | 525篇 |
2019年 | 718篇 |
2018年 | 831篇 |
2017年 | 651篇 |
2016年 | 699篇 |
2015年 | 849篇 |
2014年 | 1199篇 |
2013年 | 1691篇 |
2012年 | 2508篇 |
2011年 | 2786篇 |
2010年 | 1574篇 |
2009年 | 1469篇 |
2008年 | 2368篇 |
2007年 | 2652篇 |
2006年 | 2495篇 |
2005年 | 2597篇 |
2004年 | 2333篇 |
2003年 | 2205篇 |
2002年 | 2029篇 |
2001年 | 349篇 |
2000年 | 273篇 |
1999年 | 395篇 |
1998年 | 457篇 |
1997年 | 342篇 |
1996年 | 337篇 |
1995年 | 279篇 |
1994年 | 244篇 |
1993年 | 272篇 |
1992年 | 229篇 |
1991年 | 219篇 |
1990年 | 182篇 |
1989年 | 162篇 |
1988年 | 172篇 |
1987年 | 151篇 |
1986年 | 118篇 |
1985年 | 178篇 |
1984年 | 246篇 |
1983年 | 206篇 |
1982年 | 242篇 |
1981年 | 250篇 |
1980年 | 242篇 |
1979年 | 116篇 |
1978年 | 131篇 |
1977年 | 127篇 |
1976年 | 114篇 |
1974年 | 92篇 |
1973年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
152.
Effective high-capacity gutless adenoviral vectors mediate transgene expression in human glioma cells. 总被引:2,自引:0,他引:2
Marianela Candolfi James F Curtin Wei-Dong Xiong Kurt M Kroeger Chunyan Liu Altan Rentsendorj Hasmik Agadjanian Lali Medina-Kauwe Donna Palmer Philip Ng Pedro R Lowenstein Maria G Castro 《Molecular therapy》2006,14(3):371-381
Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function. 相似文献
153.
Marika A. Artz Johannes M. M. Boots Gerry Ligtenberg Joke I. Roodnat Maarten H. L. Christiaans Pieter F. Vos Philip Moons George Borm Luuk B. Hilbrands 《American journal of transplantation》2004,4(6):937-945
Long-term use of cyclosporine after renal transplantation results in nephrotoxicity and an increased cardiovascular risk profile. Tacrolimus may be more favorable in this respect. In this randomized controlled study in 124 renal transplant patients, the effects of conversion from cyclosporine to tacrolimus on renal function, cardiovascular risk factors, and perceived side-effects were investigated after a follow-up of 2 years. After conversion from cyclosporine to tacrolimus renal function remained stable, whereas continuation of cyclosporine was accompanied by a rise in serum creatinine from 142 +/- 48 micromol/L to 157 +/- 62 micromol/L (p < 0.05 comparing both groups). Conversion to tacrolimus resulted in a sustained reduction in systolic and diastolic blood pressure, and a sustained improvement in the serum lipid profile, leading to a reduction in the Framingham risk score from 5.7 +/- 4.3 to 4.8 +/- 5.3 (p < 0.05). Finally, conversion to tacrolimus resulted in decreased scores for occurrence of and distress due to side-effects. In conclusion, conversion from cyclosporine to tacrolimus in stable renal transplant patients is beneficial with respect to renal function, cardiovascular risk profile, and side-effects. Therefore, for most renal transplant patients tacrolimus will be the drug of choice when long-term treatment with a calcineurin inhibitor is indicated. 相似文献
154.
Kerry B Goralski Philip D Acott Albert D Fraser David Worth Christopher J Sinal 《Drug metabolism and disposition》2006,34(2):288-295
Cyclosporin A (CyA) toxicity is a common occurrence in pediatric organ transplant patients. We hypothesized that reduced mdr1a expression in newborn and developing mice would affect CyA accumulation within organs and/or toxicity. For functional studies, CyA was administered (5 mg kg(-1) i.p.) to 1-, 12-, and 19-day, and adult male and female mdr1a+/+ and mdr1a-/- mice. Peak blood CyA was lower in 1-, 12-, and 19-day-old (1000 ng ml(-1)) versus adult (1500 ng ml(-1)) mice but was similar in mdr1a+/+ and mdr1a-/- mice. Kidney mdr1a expression (measured by quantitative polymerase chain reaction) increased 2.5-fold in 19-day-old male and female mice and increased another 4-fold in adult females compared with adult males. Liver mdr1a expression increased 6-fold by day 12 compared with neonatal mice. Thereafter, maintenance of hepatic mdr1a expression in females and a reduction to neonatal levels in males was observed. Kidney/blood (8- to 9-fold) and liver/blood (12- to 15-fold) CyA levels were highest on days 12 and 19 and were not dependent on maturational changes in mdr1a mRNA levels. Adults had higher brain expression of mdr1a mRNA (3-fold), a corresponding 5-fold increase in immunodetectable P-glycoprotein, and 80% lower brain accumulation of CyA compared with 1-day-old mice. Conversely, in mdr1a-null mice, brain/blood CyA was similar in newborn and adult mice. A similar pattern was observed for the brain accumulation of the mdr1a substrate 3H-digoxin. We conclude that the risk for central nervous system drug toxicity could be higher in neonates or young children as a consequence of underdeveloped P-glycoprotein. 相似文献
155.
Philip B. Berger 《Canadian Medical Association journal》1994,150(2):221-222
156.
Regina F. Gandour-Edwards Paul J. Donald Philip J. Vogt Robert Munn Kyung-Whan Min 《Head & neck》1994,16(4):379-382
Background. Carcinosarcoma or true malignant mixed tumor of the parotid gland is extremely rare, accounting for <1% of all salivary gland malignancies. Methods. A 63-year-old woman presented with a 5-cm right parotid mass which was resected with a radical parotidectomy and infratemporal fossa dissection. Results. The tumor contained two distinctive histologic patterns, that of a poorly differentiated ductal carcinoma and a pleomorphic rhabdomyosarcoma. Additionally, a residual focus of pleomorphic adenoma was present peripherally, Immunohistochemical and electron microscopic studies confirmed the skeletal muscle differentiation. Conclusions. The pattern of combined rhabdomyosarcoma and ductal carcinoma has not been previously reported and adds further evidence to the myoepithelial derivation of these tumors. © 1994 John Wiley & Sons, Inc. 相似文献
157.
Elchanan Nussinson Lica Vigder M.D. Zvi Kaveh Haim Gutman Philip Trougouboff Nathan Tzur 《Abdominal imaging》1988,13(1):306-308
A case of subserosal gastric neurilemmoma is hereby presented. This reported case is unique in its clinical presentation including the appearance of acute abdomen and fever subsequent to unremarkable and uneventful upper gastrointestinal endoscopy. The tendency of neurilemmoma to cause mucosal ulceration with fistula formation probably led to this clinical presentation. The role of computed tomography in establishing diagnosis of exogastric tumor is emphasized. 相似文献
158.
Mitchel A Kling Salvatore Alesci Gyorgy Csako Rene Costello David A Luckenbaugh Omer Bonne Roman Duncko Wayne C Drevets Husseini K Manji Dennis S Charney Philip W Gold Alexander Neumeister 《Neuropsychopharmacology》2007,62(4):309-313
BACKGROUND: Major depressive disorder (MDD) shows increased coronary artery disease (CAD) risk of unknown mechanism(s). MDD is more common in women than men; CAD diagnosis can be difficult in women. Elevations of the inflammatory markers C-reactive protein (CRP) and serum amyloid A (SAA) predict increased CAD risk in populations; few data on these markers exist in MDD, particularly in remitted patients. METHODS: We measured fasting am serum CRP (high sensitivity, CRP(hs)) and SAA in 18 unmedicated, remitted women with MDD (mean age 41 +/- (SD)12, body mass index (BMI) 25.2 +/- 4.1 kg/m(2)) and 18 BMI-matched healthy control subjects (age 36 +/- 10, BMI 25.3 +/- 3.8 kg/m(2)) on 2 separate occasions, > or = 6 days apart. RESULTS: Repeat SAA and CRP(hs) measurements strongly correlated across study days (SAA: r = .83, p < .001; CRP(hs): r = .94, p < .001). Both SAA (5.30 +/- 3.39 vs. 2.84 +/- 1.87 mg/L, p < .005) and CRP(hs) (3.23 +/- 3.17 vs. 1.12 +/- 1.45 mg/L; p < .01) were significantly elevated in MDD women versus controls. CONCLUSIONS: Elevated SAA and CRP(hs) in remitted, unmedicated women with MDD indicate a pro-inflammatory state unrelated to current depressive symptoms or pharmacotherapy. These findings suggest that inflammatory mechanisms may in part underlie findings of increased CAD risk in MDD. 相似文献
159.
Efficacy and safety of transcranial magnetic stimulation in the acute treatment of major depression: a multisite randomized controlled trial. 总被引:6,自引:0,他引:6
John P O'Reardon H Brent Solvason Philip G Janicak Shirlene Sampson Keith E Isenberg Ziad Nahas William M McDonald David Avery Paul B Fitzgerald Colleen Loo Mark A Demitrack Mark S George Harold A Sackeim 《Neuropsychopharmacology》2007,62(11):1208-1216
BACKGROUND: We tested whether transcranial magnetic stimulation (TMS) over the left dorsolateral prefrontal cortex (DLPFC) is effective and safe in the acute treatment of major depression. METHODS: In a double-blind, multisite study, 301 medication-free patients with major depression who had not benefited from prior treatment were randomized to active (n = 155) or sham TMS (n = 146) conditions. Sessions were conducted five times per week with TMS at 10 pulses/sec, 120% of motor threshold, 3000 pulses/session, for 4-6 weeks. Primary outcome was the symptom score change as assessed at week 4 with the Montgomery-Asberg Depression Rating Scale (MADRS). Secondary outcomes included changes on the 17- and 24-item Hamilton Depression Rating Scale (HAMD) and response and remission rates with the MADRS and HAMD. RESULTS: Active TMS was significantly superior to sham TMS on the MADRS at week 4 (with a post hoc correction for inequality in symptom severity between groups at baseline), as well as on the HAMD17 and HAMD24 scales at weeks 4 and 6. Response rates were significantly higher with active TMS on all three scales at weeks 4 and 6. Remission rates were approximately twofold higher with active TMS at week 6 and significant on the MADRS and HAMD24 scales (but not the HAMD17 scale). Active TMS was well tolerated with a low dropout rate for adverse events (4.5%) that were generally mild and limited to transient scalp discomfort or pain. CONCLUSIONS: Transcranial magnetic stimulation was effective in treating major depression with minimal side effects reported. It offers clinicians a novel alternative for the treatment of this disorder. 相似文献
160.