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101.
102.
The purpose of this study was to evaluate the clinical implementation of tangential field IMRT using sliding window technique and to compare dosimetric parameters with 3-dimensional conformal radiation therapy (3DCRT). Twenty breast cancer patients were randomly selected for comparison of intensity modulated radiation therapy (IMRT)-based treatment plan with 3DCRT. Inverse treatment was performed using the sliding window technique, employing the Eclipse® Planning System (version 7.1.59, Varian, Palo Alto, CA). The dosimetric parameters compared were V95 (the percentage of target volume getting ≥95% of prescribed dose), V105, V110, and dose homogeneity index, DHI (percentage of target volume getting between 95% and 110% of prescribed dose). The mean V95, DHI, V105, and V110 for target volume for IMRT vs. 3D were 90.6% (standard deviation [SD]: 3.2) vs. 91% (SD: 3.0), 87.7 (SD: 6.0) vs. 82.6 (SD: 7.8), 27.3% (SD: 20.3) vs. 49.4% (SD: 14.3), and 2.8 (SD: 5.6) vs. 8.4% (SD: 7.4), respectively. DHI was increased by 6.3% with IMRT compared to 3DCRT (p < 0.05). The reductions of V105 and V110 for the IMRT compared to 3DCRT were 44.7% and 66.3%, respectively (p < 0.01). The mean dose and V30 for heart with IMRT were 2.3 (SD: 1.1) and 1.05 (SD: 1.5) respectively, which was a reduction by 6.8% and 7.9%, respectively, in comparison with 3D. Similarly, the mean dose and V20 for the ipsilateral lung and the percentage of volume of contralateral volume lung receiving > 5% of prescribed dose with IMRT were reduced by 9.9%, 2.2%, and 35%, respectively. The mean of total monitor units used for IMRT and 3DCRT was about the same (397 vs. 387). The tangential field IMRT for intact breast using sliding window technique was successfully implemented in the clinic. We have now treated more than 1000 breast cancer patients with this technique. The dosimetric data suggest improved dose homogeneity in the breast and reduction in the dose to lung and heart for IMRT treatments, which may be of clinical value in potentially contributing to improved cosmetic results and reduced late treatment-related toxicity.  相似文献   
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Novel acrylate monomer of quinoline-based chalcone 1-(4-(7-chloroquinolin-4-ylamino)phenyl) acrylate (CPA) was synthesized using (4-(2-chloroquinolin-5-ylamino)phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one (CPE) and acryloyl chloride. CPA is characterized by different techniques like IR, 1H NMR and UV–visible spectrometry techniques. Poly(CPA), poly(CPA-co-AA) and poly(CPA-co-HEA) are prepared by solution polymerization technique using CPA, acrylic acid (AA) and hydroxyethylacrylate (HEA), respectively. The antimicrobial activities of the compounds are tested using four different micro-organisms. In vitro cumulative drug release studies are done using UV visible spectroscopic technique. The molecular weights of these polymers are found to be around 5000 g/mol. The synthesized polymers showed two stages of thermal decomposition temperature centred around 220 and 350 °C, respectively. The antimicrobial activity of the polymer sample is found to be very high and especially for gram-negative bacteria with a minimum value of 3.91 μg/mL. The in vitro drug-releasing rate is dependent on the comonomer, pH and temperature of the medium.  相似文献   
107.
Ectopic xenografting of 'donor' feline testicular tissue into a 'recipient' immunodeficient mouse is a promising tool to preserve the male genome from genetically valuable felids. To define parameters under which the technique can succeed, we compared the effect of donor age on xenograft spermatogenesis among four age groups of domestic cats (Felis catus; age range 8 weeks to 15 months). In all cases, fresh tissue was grafted into castrated mice and collected 10, 30 and 50 weeks later. The percentage of xenografts recovered decreased as donor age increased. Mature testicular spermatozoa were observed in xenografts from the 8 and 9-16 week age groups; only a single 7-month-old donor produced elongating spermatids and xenografts from donors >/= 8 months of age degenerated. Seminal vesicle weight, an indicator of bioactive testosterone, was not significantly different between donors aged 8 weeks to 7 months and controls, suggesting that xenograft Leydig cells were ultimately functional even in the 5-7 month age group. Regardless of donor age, production of mature spermatozoa from xenografts was markedly delayed compared with controls. Comparison of xenografts that produced sperm with normal controls revealed a decrease in tubule cross-sections having post-meiotic germ cells. Together, these results indicate that the maximum practical donor age was just before the onset of puberty and that even successful xenografts had abnormalities in spermatogenesis.  相似文献   
108.
The phytoestrogen genistein suppresses cell-mediated immunity in mice   总被引:9,自引:0,他引:9  
The soy phytoestrogen, genistein, induces thymic atrophy when administered to ovariectomized mice by injection or in the diet. Injected genistein also causes decreased humoral immunity, but the effects of genistein on cell-mediated immunity have not been addressed. Here we examined effects of injected and dietary genistein on cell-mediated immune responses. Female C57BL/6 mice (25- to 27-days-old) were ovariectomized, then placed on phytoestrogen-free feed 5 days later. Seven days after ovariectomy, they were given daily subcutaneous injections of either dimethylsulfoxide (DMSO) or genistein (8, 20, 80 mg/kg) for 28 days; some mice were given 80 mg/kg genistein plus the anti-estrogen ICI 182,780 (5 mg/kg/week). Cell-mediated immune response was tested by analyzing the delayed-type hypersensitivity (DTH) response to a hapten, 4-hydroxy-3-nitrophenyl acetyl succinimide (NP-O-SU), at the end of treatment. Reversibility of the effects of genistein was tested by measuring the DTH response in mice that were given genistein (20 or 80 mg/kg) for 28 days, then allowed to recover for 28 days. To determine if dietary genistein could affect cell-mediated immunity, mice ovariectomized as above were fed genistein at 0, 1000 or 1500 parts per million (ppm) for 28 days. There was a 46-67% decrease in the DTH response in the footpads of mice injected with 8-80 mg/kg genistein compared with controls (P<0.05 vs control for all treatment groups); these effects were reversible. On histopathological examination of the feet, there was decreased cell infiltration in genistein-treated animals compared with controls, and the numbers of CD4(+) and CD8(+) T cells in popliteal lymph nodes were reduced. The effects of genistein are mediated through both estrogen receptor (ER) and non-ER pathways, as the anti-estrogen ICI 182,780 only partially blocked the effects of genistein on the DTH response. Dietary genistein (1000 or 1500 ppm) decreased cell-mediated immunity while producing serum genistein concentrations in the physiological range for humans under certain nutritional conditions. Further work is needed to determine if dietary genistein and phytoestrogen exposure can produce effects on cell-mediated immunity in humans or other animals under various nutritional conditions.  相似文献   
109.

Aims

Recent guidelines have advocated for stricter systolic blood pressure (SBP) control in heart failure with preserved ejection fraction (HFpEF), though data regarding the optimal SBP in HFpEF are sparse.

Methods and results

We analysed participants from the Americas from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) study with available baseline and 8‐week visit SBP data (n = 1645). We related baseline SBP to several efficacy and safety outcomes. To determine whether blood pressure lowering was responsible for the potential beneficial effects of spironolactone observed in the Americas, we assessed the randomized treatment adjusting for baseline and change in 8‐week SBP. The average age was 71.7 ± 9.7 years, 50% were women, and 79% were White. Patients in the lowest baseline SBP quartile were less often female, more often White, had lower body mass index, lower baseline diastolic blood pressure and pulse pressure, and more often had atrial fibrillation. After multivariable adjustment, there was no relationship observed between baseline SBP quartiles and any outcome. Spironolactone reduced SBP by 4.4 ± 0.6 mmHg compared with placebo (and consistently across baseline SBP quartiles). There was minimal change in the treatment effect for all outcomes after adjusting for baseline SBP and 8‐week change in SBP.

Conclusion

No relationship was observed between baseline SBP quartiles and outcomes in TOPCAT. The anti‐hypertensive effects of spironolactone did not account for the potential benefit in cardiovascular outcomes in the Americas.
  相似文献   
110.
BACKGROUND: The role of endoscopic retrograde cholangiopancreatography (ERCP) in the management of acute pancreatitis has evolved over years since its introduction in 1968. Its importance in diagnosing the etiology of pancreatitis has steadily declined with the advent of less invasive diagnostic tools. The therapeutic implications of ERCP in acute pancreatitis are many fold and are directed towards management of known etiological factors or its related complications. This article highlights the current status of ERCP in acute pancreatitis. DATA SOURCES: An English literature search using PubMed database was conducted on ERCP in acute pancreatitis, the etiologies and complications of pancreatitis amenable to endotherapy and other related subjects, which were reviewed. RESULTS: ERCP serves as a primary therapeutic modality for management of biliary pancreatitis in specific situations, pancreatitis due to microlithiasis, specific types of sphincter of Oddi dysfunction, pancreas divisum, ascariasis and malignancy. In recurrent acute pancreatitis and smoldering pancreatitis it has a definite therapeutic utility. Complications of acute pancreatitis including pancreatic-duct disruptions or leaks, benign pancreatic-fluid collections and pancreatic necrosis can be beneficially dealt with. Intraductal ultrasound and pancreatoscopy during ERCP are useful in detecting pancreatic malignancy. CONCLUSIONS: The role of ERCP in acute pancreatitis is predominantly therapeutic and occasionally diagnostic. Its role in the management continues to evolve and advanced invasive procedures should be undertaken only in centers dedicated to pancreatic care.  相似文献   
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