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71.
Flow mediated brachial dilatation (FMD) and carotid intima-media thickness (IMT) have been a surrogate for early atherosclerosis. Slow coronary flow in a normal coronary angiogram is not a rare condition, but its pathogenesis remains unclear. A total of 85 patients with angina were evaluated of their brachial artery FMD, carotid IMT and conventional coronary angiography. Coronary flow was quantified using the corrected thrombosis in myocardial infarction (TIMI) frame count method. Group I was a control with normal coronary angiography (n = 41, 56.1 ± 8.0 yr) and group II was no significant coronary stenosis with slow flow (n = 44, 56.3 ± 10.0 yr). Diabetes was rare but dyslipidemia and family history were frequent in group II. Heart rate was higher in group II than in group I. White blood cells, especially monocytes and homocysteine were higher in group II. The FMD was significantly lower in group II than in group I. Elevated heart rate, dyslipidemia and low FMD were independently related with slow coronary flow in regression analysis. Therefore, endothelial dysfunction may be an earlier vascular phenomenon than increased carotid IMT in the patients with slow coronary flow.  相似文献   
72.
Fluid and HCO(3)(-) secretion is a vital function of all epithelia and is required for the survival of the tissue. Aberrant fluid and HCO(3)(-) secretion is associated with many epithelial diseases, such as cystic fibrosis, pancreatitis, Sj?gren's syndrome, and other epithelial inflammatory and autoimmune diseases. Significant progress has been made over the last 20 years in our understanding of epithelial fluid and HCO(3)(-) secretion, in particular by secretory glands. Fluid and HCO(3)(-) secretion by secretory glands is a two-step process. Acinar cells secrete isotonic fluid in which the major salt is NaCl. Subsequently, the duct modifies the volume and electrolyte composition of the fluid to absorb the Cl(-) and secrete HCO(3)(-). The relative volume secreted by acinar and duct cells and modification of electrolyte composition of the secreted fluids varies among secretory glands to meet their physiological functions. In the pancreas, acinar cells secrete a small amount of NaCl-rich fluid, while the duct absorbs the Cl(-) and secretes HCO(3)(-) and the bulk of the fluid in the pancreatic juice. Fluid secretion appears to be driven by active HCO(3)(-) secretion. In the salivary glands, acinar cells secrete the bulk of the fluid in the saliva that is driven by active Cl(-) secretion and contains high concentrations of Na(+) and Cl(-). The salivary glands duct absorbs both the Na(+) and Cl(-) and secretes K(+) and HCO(3)(-). In this review, we focus on the molecular mechanism of fluid and HCO(3)(-) secretion by the pancreas and salivary glands, to highlight the similarities of the fundamental mechanisms of acinar and duct cell functions, and to point out the differences to meet gland-specific secretions.  相似文献   
73.

Background

Regular exposure to tobacco smoke at home causes airway inflammation and altered cytokine regulation; however, there is variation between individuals of different countries.

Objective

To determine effects of passive smoking on plasma IL4, TNFá, and CRP in healthy male school-children in Khartoum.

Methods

A total of 135 male school-pupils (69 passive smokers and 66 non-smokers) were selected randomly from three primary schools for boys in Khartoum. Information about smoking history was collected from each pupil and his parents using a questionnaire. Plasma CRP, IL4 and TNFá were measured using commercially available ELISA kits.

Results

Plasma IL4 and TNFá in the passive smokers (mean ± SEM) is at 2.92 ± 0.93 and 19.78 ± 4.67 pg/ml respectively; whereas in the non-smokers . It is at 0.45 ± 0.28 and 5.05 ± 1.54 pg/ml respectively. The difference between the two groups is statistically significant (p <0.05). The mean plasma IL4 and TNFá were lowest with no exposure, higher with moderate exposure, and highest with heavy exposure (P < 0.05). Plasma CRP showed insignificant difference between the two groups.

Conclusion

Passive smoking causes significant rise in plasma TNFá and IL4 with a dose dependent effect among school-pupils in Khartoum.  相似文献   
74.
Jeong EG  Lee SH  Yoo NJ  Lee SH 《Pathology》2008,40(1):31-34
AIMS: The Fas-Fas ligand system is considered a major pathway for induction of apoptosis in cells and tissues. FLASH was identified as a pro-apoptotic protein that transmits apoptosis signal during Fas-mediated apoptosis. PTPN13 interacts with Fas and functions as both suppressor and inducer of Fas-mediated apoptosis. There are polyadenine tracts in both FLASH (A8 and A9 in exon 8) and PTPN13 (A8 in exon 7) genes that could be frameshift mutation targets in colorectal carcinomas. Because genes encoding proteins in Fas-mediated apoptosis frequently harbor somatic mutations in cancers, we explored the possibility as to whether mutations of FLASH and PTPN13 are a feature of colorectal carcinomas. METHODS: We analysed human FLASH in exon 8 and PTPN13 in exon 7 for the detection of somatic mutations in 103 colorectal carcinomas by a polymerase chain reaction (PCR)- based single-strand conformation polymorphism (SSCP). RESULTS: We detected two mutations in FLASH gene, but none in PTPN13 gene. However, the two mutations were not frameshift (deletion or insertion) mutations in the polyadenine tracts of FLASH. The two mutations consisted of a deletion mutation (c.3734-3737delAGAA) and a missense mutation (c.3703A>C). CONCLUSION: These data indicate that frameshift mutation in the polyadenine tracts in both FLASH and PTPN13 genes is rare in colorectal carcinomas. Also, the data suggest that both FLASH and PTPN13 mutations in the polyadenine tracts may not have a crucial role in the pathogenesis of colorectal carcinomas.  相似文献   
75.
Bartonella species cause serious human infections globally, including bacillary angiomatosis, Oroya fever, trench fever, and endocarditis. We describe a patient who had fever and splenomegaly after traveling to Peru and also had bacteremia from an organism that resembled Bartonella bacilliformis, the causative agent of Oroya fever, which is endemic to Peru. However, genetic analyses revealed that this fastidious bacterium represented a previously uncultured and unnamed bartonella species, closely related to B. clarridgeiae and more distantly related to B. bacilliformis. We characterized this isolate, including its ability to cause fever and sustained bacteremia in a rhesus macaque. The route of infection and burden of human disease associated with this newly described pathogen are currently unknown.  相似文献   
76.

Purpose

To identify the clinical features and outcomes of endogenous endophthalmitis in Korea.

Materials and Methods

We reviewed 18 patients with endogenous endophthalmitis at 2 Korean hospitals, treated over a 14 year period between January 1993 and December 2006.

Results

The comorbidities observed in these cases were diabetes mellitus and liver cirrhosis. The most common pathogens, which were found in 7 patients each (38.9%), were Klebsiella pneumonia and Pseudomonas aeruginosa. All patients were treated with systemic antibiotics and fortified topical antibiotics. A surgical approach including vitrectomy was performed in 9 cases (50.0%). The prognosis was generally poor, and visual acuity improved slightly in 6 patients (33.3%).

Conclusion

In this study, diabetes mellitus and Klebsiella pneumonia showed a close relationship with endogenous endophthalmitis, respectively. Endogenous endophthalmitis is a serious risk to sight and careful attention to establishing the diagnosis and management may decrease the ocular morbidity.  相似文献   
77.
Five Babesia bovis recombinant proteins, including merozoite surface antigen 2c (BbMSA-2c), C-terminal rhoptry-associated protein 1 (BbRAP-1/CT), truncated thrombospondin-related anonymous protein (BbTRAP-T), spherical body protein 1 (BbSBP-1), and spherical body protein 4 (BbSBP-4), were evaluated as diagnostic antigens to detect the infection in cattle. The recombinant proteins were highly antigenic when tested with experimentally B. bovis-infected bovine serum in Western blot analysis. Furthermore, five antisera that had been raised against each of the recombinant proteins reacted specifically with the corresponding authentic protein, as determined in Western blot analysis. Next, enzyme-linked immunosorbent assays (ELISAs) using these recombinant proteins were evaluated for diagnostic use, and the sensitivity and specificity of each protein were demonstrated with a series of serum samples from experimentally B. bovis-infected cattle. Furthermore, a total of 669 field serum samples collected from cattle in regions of B. bovis endemicity in seven countries were tested with the ELISAs, and the results were compared to those of an indirect fluorescent antibody test (IFAT), as a reference. Among five recombinant antigens, recombinant BbSBP-4 (rBbSBP-4) had the highest concordance rate (85.3%) and kappa value (0.705), indicating its reliability in the detection of specific antibodies to B. bovis in cattle, even in different geographical regions. Overall, we have successfully developed an ELISA based on rBbSBP-4 as a new serological antigen for a practical and sensitive test which will be applicable for epidemiologic survey and control programs in the future.  相似文献   
78.
Although it is known that the tetraploid embryo contributes only to the placenta, the question of why tetraploid embryos differentiate into placenta remains unclear. To study the effect of electrofusion on the development of mouse tetraploid oocytes, mouse two‐cell embryos were fused and cultured in vitro in Chatot‐Ziomek‐Bavister medium. After electrofusion, two chromosome sets from the tetraploid blastomere were individually duplicated before nuclear fusion. At 8–10 hr after electrofusion, each chromosome set was condensing and the nuclear membrane was breaking down. Around 12–14 hr after electrofusion, the two chromosome sets had combined together and had reached the second mitotic metaphase, at this point with 8n sets of chromosomes. Interestingly, we discovered that expression of OCT4, an inner cell mass cells biomarker, is lost by the tetraploid expanded blastocysts, but that CDX2, a trophectoderm cells biomarker, is strongly expressed at this stage. This observation provides evidence clarifying why tetraploid embryos contribute only to trophectoderm. Developmental Dynamics 240:1660–1669, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
79.
80.
Psoriasis is a chronic inflammatory skin disease, characterized by a combination of abnormal proliferation of keratinocytes, immunology and vascular proliferation. Proteomic analyses have revealed some clues regarding the pathogenesis of psoriasis. In the present study, we conducted an investigation of different proteomes of psoriatic lesional skin, and compared them with those of normal and non-lesional psoriatic skin. We performed 2-D gel electrophoresis, liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis and database searches. Expression of proteins were evaluated by immunoblot and immunohistochemistry analyses. Our data showed differential expression of 74 and 145 protein spots in non-lesional and lesional psoriatic skin, respectively. Eleven of 36 proteins, which were identified by LC-MS/MS, were categorized as apoptosis-regulating proteins. Other protein spots were categorized as proteins with involvement in the negative regulation of apoptosis, defense response-related proteins and inflammatory response. Of particular interest, increased expression of glutathione S transferase 1 (GSTP1) and peroxiredoxin 2 (PRDX2), which are involved in the Redox balance system, and SFN, which is involved in the cellular proliferation system, was observed in psoriatic lesional skin. Localization of GSTP1 and SFN was observed above the middle layer of the epidermis in psoriatic skin lesions. Expression of PRDX2 was clearly observed below the middle layer of the epidermis in chronic type psoriatic skin lesions. Taken together, 36 identified proteins were associated with biological regulation, including regulation of cell death, defense response, inflammatory response and reactive oxygen species (ROS) regulation. PRDX2 and GSTP1 may play roles in compensating mechanisms for reduction of ROS stress, and SFN may play roles in prevention of cancer development in proliferating cells through G2/M cell cycle arrest upon accidental DNA damage within psoriatic skin lesions.  相似文献   
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