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81.
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84.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mainly invades the respiratory system, but may also cause various cardiovascular complications. We report a rare case of myocarditis associated with SARS-CoV-2 infection. A 61-year-old man was admitted to the hospital with a positive nucleic acid test for SARS-CoV-2. A sudden increase in troponin level (up to .144 ng/mL) was observed on the 8th day after admission. He developed symptoms of heart failure and progressed rapidly to cardiogenic shock. Echocardiography on the same day showed reduced left ventricular ejection fraction, reduced cardiac output, and segmental ventricular wall motion abnormalities. Takotsubo cardiomyopathy associated with SARS-CoV-2 infection was considered based on the typical echocardiography findings. We immediately started veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment. The patient was successfully withdrawn from VA-ECMO after 8 days following recovery of ejection fraction to 65% and all indicators qualifying the withdrawal criteria. Echocardiography plays an important role in dynamic monitoring of cardiac changes in such cases and can help determine the timing of extracorporeal membrane oxygenation treatment and withdrawal.  相似文献   
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The spontaneous chemiluminescence activity (CL-A) of peripheral mononuclear cells (MNC) was examined in Lewis rats with acute experimental allergic encephalomyelitis (EAE), compared to rats immunized with complete adjuvant (n = 11) and healthy animals (n = 16). In rats with EAE, CL-A increased sharply 8-9 days after immunization (3420 +/- 3124 counts/10 s, n = 16) at the time of flattening of the weight curve. This CL-A peak was compared to that of animals immunized with complete adjuvant: 765 +/- 441 counts/10 s (P = 0.01) and healthy rats: 450 +/- 172 counts/10 s (P = 0.0001). After this initial peak in EAE rats, CL-A decreased almost to normal values when animals lost weight (746 +/- 251 counts, n = 19) and tail paralysis developed (557 +/- 251 counts/10 s, n = 15). CL-A increased again with the onset of paralysis of the extremities (1527 +/- 990 counts/10 s, n = 11), followed by a decrease as the clinical course deteriorated. Finally, CL-A approached normal values as the animals improved. A significant increase in the number of meningeal (P less than 0.01) and perivascular (P less than 0.01) cells in the CNS coincided with the initial CL-A peak. Gel filtration of the serum of rats with increased CL-A revealed at least one substance, with a molecular weight between 13,700 and 43,000 Da, which stimulated the CL-A of normal mononuclear cells.  相似文献   
87.

Background

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a genetic predisposition, and the traditional Chinese medicine Morinda officinalis and its roots are characterized with anti-inflammatory effects and have been used for the treatment of various disease. However, it is still largely unknown whether Morinda officinalis extract (MOE) can be used for the treatment of AD.

Objectives

In our study we aimed to determine whether MOE could ameliorate 2,4-dinitrochlorobenzene (DNCB)-induced AD and elucidate molecular mechanisms.

Methods

We established an AD mouse model by using DNCB. Skin pathological analysis and ELISA assay were used to detect the effect of MOE on the inflammation of AD model mouse skin and the expression changes of inflammatory factors, and further functional verification was performed in TNF-α/IFN-γ-induced HaCaT cells.

Results

Our in vivo experiments confirmed that MOE remarkably reduced DNCB-induced AD lesions and symptoms, such as epidermal and dermal thickness and mast cell infiltration and inflammatory cytokines secretion in the mice models. In addition, the underlying mechanisms by which MOE ameliorated AD had been uncovered, and we verified that MOE inhibited MALAT1 expression in AD, resulting in attenuated expression of C-C chemokine receptor type 7 (CCR7) regulated by MALAT1-sponge miR-590-5p in a competing endogenous RNA (ceRNA) mechanisms-dependent manner, thereby inhibiting TNF-α/IFN-γ-induced cellular proliferation and inflammation.  相似文献   
88.
A preliminary screening of numerous species of the order Actinomycetales, especially of the genera Mycobacterium, Nocardia, Rhodococcus, Pseudonocardia, and Streptomyces, showed that many of them are able to metabolize benzoate (B) and p-hydroxybenzoate (pHB) as indicated by growth and change of color of the pH-indicator of an agar medium. Subsequent experiments with liquid cultures which allowed the analysis of substrate utilization by thin layer chromatography confirmed these results. The study of the degradative pathway proved that B was metabolized via catechol (C), pHB via protocatechuate (P) and m-hydroxybenzoate (mHB) via gentisate (G). The aromatic ring of C and P was subjected to an ortho-cleavage; only one strain of Noc. asteroides degraded C via a meta-cleavage, but P via an ortho-cleavage. Cell free extracts of four selected organisms exhibited activity of C-1,2-dioxygenase (C-1,2-O) and/or P-3,4-dioxygenase (P-3,4-O), depending on the growth substrate used for precultivation. In Streptomyces C-1,2-O was only found in cells grown on B, and P-3,4-O only in cells grown on pHB. On the contrary, in Rhodococcus rhodochrous B-cells oxidized C as well as P, while P-cells possessed only P-3,4-O-activity.  相似文献   
89.
Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.  相似文献   
90.
The microbiological performance of BBL CHROMagar Orientation medium and CPS ID2 agar was compared to that of Columbia agar with 5% sheep blood and MacConkey agar without crystal violet for the enumeration and presumptive identification of bacteria responsible for urinary tract infections. Of a total of 658 clinical urine specimens, 118 specimens yielded no growth, 402 specimens yielded growth with cell counts of > or = 10(5) CFU/ml, and 138 specimens yielded growth with cell counts of < 10(5) CFU/ml. Of the specimens with cell counts of > or = 10(5) CFU/ml, 163 were pure cultures and 239 were mixed cultures. A total of 266 Escherichia coli organisms were isolated on both chromogenic media, 260 were isolated on blood agar, and 248 were isolated on MacConkey agar. One strain (0.4%) failed to develop the expected pink color on CHROMagar Orientation medium, and 23 strains (8.7%) failed to develop the expected pink color on CPS ID2 agar. Enterococci (CHROMagar Orientation medium, n = 266; CPS ID2 agar, n = 265) produced small blue-green colonies on both chromogenic media. Fifty of the mixed cultures contained enterococci that were detected only on the chromogenic media. The Klebsiella-Enterobacter-Serratia (KES) and the Proteus-Morganella-Providencia (PMP) groups could be identified on both chromogenic media. Of 66 isolates of the KES group, 63 grew with the expected color on CHROMagar Orientation medium and 58 of 64 isolates grew with the expected color on CPS ID2 agar. Other microorganisms required further identification. The use of chromogenic medium formulations offers a time-saving method for the reliable detection, enumeration, and presumptive identification of urinary tract pathogens. One of the greatest advantages of these media is the easy recognition of mixed cultures.  相似文献   
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