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21.
Background: One of the most challenging problems in clinical surgery is management of an extensive duodenal injury. In its management, there are limitations in using jejunal serosal patch and other conventional methods in specific conditions. This study was performed to compare treatment of large duodenal defects by a gallbladder serosal patch and the gallbladder mucosal patch in a dog as an animal model. Methods: A duodenal defect (2 cm, about 50% of the total circumference) was created in the second portion of the duodenum in eight dogs. The animals were divided into two equal groups, with group 1 undergoing serosal patch repair and group 2 undergoing mucosal patch repair. The macroscopic and microscopic healing features of the gallbladder serosal and mucosal patch were compared. Results: None of the dogs died due to surgical complications. The whole grafted area was covered by neomucosa at the end of the third week in all animals with the gallbladder serosal patch (group 1). In this group, the scar was small; no significant narrowing of lumen was noted and serosal healing was uniformly complete. In histological examination, a complete coverage of the gallbladder serosal patch by neomucosa consisting of columnar epithelium with short villous formations was observed. In mucosal patch models (group 2), complete epitheliazation, mild fibrosis, and incomplete repair were visible. In histological examination, severe inflammation was noticed too. Conclusion: In patients with multiple trauma affecting upper gastrointestinal tracts, use of the gallbladder serosal patch method is easy and reliable. So it may be considered in the surgical management of large duodenal defects, which cannot be repaired by available conventional methods.  相似文献   
22.

Purpose

To investigate the effect of polymerization method on the stability and drug release properties of polymeric micelles formed using stereo-active block copolymers.

Methods

Diblock copolymers consisting of methoxy poly ethylene oxide (MePEO) and poly(lactide)s (PLA)s of different stereochemistry were synthesized by bulk or solution polymerization. Polymers and micelles were characterized for their chemical structure by 1H NMR, optical rotation by polarimetry, critical micellar concentration by fluorescence spectroscopy, thermal properties by differential scanning calorimetry, morphology by transmission electron microscopy and size as well as kinetic stability by dynamic light scattering. Release of encapsulated nimodipine from polymeric micelles at different levels of loading was also investigated.

Results

Solution polymerization yielded a higher degree of crystallinity for stereo-regular PLA blocks. Consequently, the related polymeric micelles were kinetically more stable than those prepared by bulk polymerization. At high drug loading levels, the release of nimodipine was more rapid from polymeric micelles with crystalline cores. At lower levels of drug loading, drug release was slower and independent of the stereochemistry of the core.

Conclusions

The results underline the effect of polymerization method in defining core crystallinity in stereoregular block copolymer micelles. It also shows the impact of core crystallinity on enhancing micellar stability and drug release.  相似文献   
23.
Cutaneous T-cell lymphomas (CTCLs) arise from specific molecular aberrations that lead to uncontrolled cell proliferation. RNA interference (RNAi) with short interfering RNAs (siRNAs) is a feasible approach to interrupt aberrant signal processing in CTCL cells, but functional biomaterial carriers are needed to effectively deliver siRNAs intracellularly. Towards this goal, we explored the utility of lipid-substituted polyethylenimines (PEI) carriers in a cell model of CTCL. Using caprylic and linoleic acid substituted 2 kDa PEI (PEI-CA and PEI-LA, respectively), we showed effective delivery of siRNA to T-lymphocyte Hut78 and Jurkat cells, but silencing of a model protein (Green Fluorescent Protein, GFP) was possible only in the Hut78 cells. To enhance siRNA delivery to Hut78 cells, a high siRNA: carrier ratio used to assemble the complexes and centrifugation of cells in the presence of complexes were found effective. The toxicities of PEI-CA and PEI-LA were significantly lower than other commercial carriers, 25 kDa PEI and Lipofectamine® RNAiMAX. This might have contributed to reduced siRNA delivery efficiency of the latter carriers. Screening several endogenous targets led us to identify phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and cyclin-dependent kinase 18 (CDK18) as viable targets to induce siRNA-mediated cell growth inhibition. The results of this study identified promising polymeric carriers and molecular targets that could control proliferation of CTCL cells based on RNAi therapy.  相似文献   
24.
Cases of filler reactions after COVID‐19 vaccination have been reported. Here, we present the first case of delayed‐type reaction (DTR) to non‐hyaluronic acid Polycaprolactone dermal filler after the second dose of Sinopharm COVID‐19 vaccine which was improved with administration of topical and intralesional steroids.  相似文献   
25.
The association of specific skin disorders with diabetes mellitus (DM) has been well established. Current literature suggests that approximately 30–91% of patients with diabetes will experience at least one cutaneous manifestation of this systemic disease in their lifetime. To date, there are limited articles summarizing the link between necrobiosis lipoidica diabeticorum (NLD) prognosis and glycemic control in patients with diabetes. The objective of the study is to summarize and appraise the available evidence assessing the relationship between glycemic control and NLD. A literature search was conducted based on MEDLINE (1946–2015), EMBASE (1980–2015), Google Scholar, and PubMed for publications that described the results of diabetes control and NLD. Further studies were identified from bibliographies of all relevant studies, gray literature, and annual scientific assemblies. All studies investigating the relationship between DM (type 1 and type 2) management and NLD were included. Two reviewers independently extracted data including demographics, type of diabetes management measures (glucose, HbA1c, insulin), comorbidities, and outcome. A total of 622 studies were identified, and 10 studies met the inclusion and exclusion criteria: two case series and eight case reports. Of the 24 patients with NLD, 13 patients reported resolution of NLD after implementing various methods of glycemic control (diabetic diet consisting of 1600 kcal/day [1 patient], insulin regimen [3 patients], and pancreatic transplantation [9 patients]). Glycemic control may have a role in influencing the prognosis of necrobiosis lipoidica in patients with diabetes; however, there is currently insufficient evidence to support or refute this claim.  相似文献   
26.
For decades it has been widely accepted that elective procedures should be delayed for at least 6-months following completion of isotretinoin therapy. However, numerous 2017 publications demonstrate the need for change in best practice. The evidence has yet to be succinctly summarized in a single article or in a stand-alone quick reference algorithm for physicians. This article’s review of all 2017 publications confirms that the 6-month delay is not necessary for all procedures and provides a simple algorithmic approach to summarize the updated recommendations for procedural delay of cosmetic procedures following systemic isotretinoin therapy. This is a useful tool for clinicians and allows patients to receive the most appropriate and timely cosmetic therapy to minimize the psychosocial impact of the skin condition.  相似文献   
27.

Background  

Although elderly Iranian immigrants in Sweden are the largest elderly group born outside Europe, little is known about their health-related quality of life (HRQL). The aim of this study was to examine the association between migration status and HRQL in a comparison of elderly Iranians in Iran, elderly Iranian immigrants in Sweden, and elderly Swedes in Sweden.  相似文献   
28.
BACKGROUND AND AIMS: In open-heart surgery, cardiopulmonary bypass (CPB) can cause a rise in the level of stress hormones such as cortisol. Reducing this hormonal response is beneficial in the recovery period. Anesthetic agents and methods used in such operations have different effects on this response. In the present study two agents (morphine and sufentanil) routinely used for the cardiac surgery in Nemazi Hospital were compared regarding their effect on the serum cortisol levels. MATERIALS AND METHODS: Thirty patients undergoing coronary artery bypass grafting (CABG) in Nemazi Hospital were selected and divided into two groups. Group 1 (16 patients received morphine in a dose of 1 mg/kg) and Group 2 (14 patients received sufentanil in a dose of 5 microg/kg). Serum cortisol levels were measured before induction of anesthesia, after tracheal intubation, after initiation of CPB and twelve hours after the termination of operation. RESULTS: Morphine and sufentanil both lowered the serum cortisol level during the operation. However, twelve hours after the operation, cortisol levels in both groups were higher than those taken in the previous set times. CONCLUSION: Neither morphine nor sufentanil in the mentioned doses could reduce the endocrine response in the postoperative period, and thus have no preference, in cardiac surgery.  相似文献   
29.
Hepatoid adenocarcinoma (HAC) is a special type of extrahepatic adenocarcinoma, which has a striking morphologic similarity to hepatocellular carcinoma. Seven HACs arising in the stomach and one in the lung, all with liver metastasis, were studied. They shared clinical features, such as old age, high serum alpha-fetoprotein level, aggressive behavior, and hepatic tumor in absence of risk factors for hepatocellular carcinoma (HCC). Morphologically, tumors were characterized by an admixture of tubulo-and/or papillary adenocarcinoma with hepatoid foci. In six cases, liver metastases showed an exclusive hepatoid differentiation, virtually indistinguishable from HCC with solid growth pattern. As HAC and HCC cannot be differentiated on the basis of morphology alone, differences in immunohistochemical reaction patterns would be of considerable diagnostic help. Immunostaining for CK7, CK8, CK18, CK19, CK20, alpha-fetoprotein, p-CEA, and HepPar1 revealed that hepatoid areas of both primary and metastatic HAC have a specific immunoprofile, distinctive of this entity. On the one hand, positivity of virtually all HACs for alpha-fetoprotein, CK8, CK18, and the membranous, canalicular staining for polyclonal carcinoembryonic antigen underline its hepatoid nature. On the other hand, positive staining for CK19 and CK20 and frequent negativity for HepPar1 in both primary tumors and their metastases were distinctive features of HAC. Furthermore, HAC differs from combined hepatocellular cholangiocarcinoma, being negative for CK7. In addition, for comparison of immunohistochemical results, we stained with the same antibody panel a tissue microarray of 121 HCCs. Comparative genomic hybridization study of three HAC supports their hepatoid differentiation as aberrations found in HAC are common in HCC (4q-, 8p-), and hepatoblastoma (Xq+), respectively.  相似文献   
30.
A series of N-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-yl]piperazinyl quinolones (7a-c) were synthesized and evaluated for in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria. The antibacterial data revealed that compounds 7a-c had strong and better activity against tested Gram-positive organisms than the reference quinolones such as ciprofloxacin, norfloxacin and enoxacin. However, all three compounds were nearly inactive against Gram-negative bacteria. Compound 7a (ciprofloxacin analogue) was the most active compound against Gram-positive bacteria (MIC=0.008-0.015 mug mL(-1)).  相似文献   
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