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排序方式: 共有351条查询结果,搜索用时 15 毫秒
51.
Parimal Bhattacherjee Brian Hammond John A. Salmon Ray Stepney Kenneth E. Eakins 《European journal of pharmacology》1981,73(1):21-28
The effects of arachidonic acid, its cyclo-oxygenase and lipoxygenase products and the synthetic chemotactic peptide, formyl-methionyl-leucyl-phenylalanine (FMLP) on leukocyte accumulation in the aqueous humour and intraocular pressure in the rabbit were studied in vivo. Substances were injected into the anterior chamber of the eyes of anesthetised rabbits using a closed circuit perfusion system. Injecction of arachidonic acid, prostaglandins E1 and E2, and the monohydroperoxy and hydroxy acids of the lipoxygenase pathway did not result in any significant accumulation of leukocytes in the anterior chamber. In contrast, FMLP and 5,12-diHETE (Leukotriene B4) resulted in significant dose dependent accumulation of leukocytes into the aqueous humour. Leukocytes appeared in the aqueous humour between 2 and 3 h after the injection of either FMLP or LTB4 and the response was maximal at 4 h. None of the lipoxygenase products tested had any effect on intraocular pressure in contrast to the profound effects observed with arachidonic acid and the E type prostaglandins. FMLP had a small but significant effect on intraocular pressure at the highest dose tested for leukocyte accumulation. These results indicate that the effects of the cyclo-oxygenase products of arachidonate metabolism are mainly vascular in the rabbit eye in contrast to the predominantly cellular effects of lipoxygenase products. Thus in the eye, the interaction of cyclo-oxygenase and lipoxygenase products of arachidonate metabolism may be important in the development of both acute and chronic ocular inflammation. 相似文献
52.
Plasma CRP level predicts left ventricular function and exercise capacity in patients with acute myocardial infarction 总被引:2,自引:0,他引:2
Pandian S Amuthan V Sukumar P Janarthanan RA Murugan S Palanichamy S Subramaniam G Annamalai M 《Indian heart journal》2005,57(1):54-57
BACKGROUND: C-reactive protein estimation can help in predicting short- and long-term prognosis after acute myocardial infarction. High plasma C-reactive protein level in the acute phase strongly indicates a poor clinical outcome of the patients with myocardial infarction. METHODS AND RESULTS: One hundred consecutive patients admitted with ST elevation myocardial infarction in the intensive coronary care unit in our hospital who were able to do symptom-limited treadmill test during early recovery phase were studied. Plasma C-reactive protein was measured at the time of admission by immunoturbidity method. The normal value of the C-reactive protein was taken as 0.8 mg/dl. Echocardiographic study was done on day three of admission and ejection fraction was estimated by modified Simpson's method. Symptom-limited treadmill exercise test was done in all the patients. Patients were classified into two groups based on level of C-reactive protein: those with low C-reactive protein level (1.26 +/- 0.91 mg/dl, n=40) and those with high C-reactive protein level (6.52 +/- 3.97 mg/dl, n=60). Ejection fraction was lower in high C-reactive protein group (46.7 +/- 11.9%) compared to low C-reactive protein group (56.9 +/- 7.7%) (p = 0.011). Exercise capacity was lower in high C-reactive protein group (2.8 +/- 1.4 METs) compared to low C-reactive protein group (5.5 +/- 2.5 METs) p = 0.027). CONCLUSIONS: C-reactive protein levels are an index of the severity of myocardial necrosis which translate to worse left ventricular function. Higher the C-reactive protein level, lower the ejection fraction and worse may be the prognosis. 相似文献
53.
Sommers JA Sharma S Doherty KM Karmakar P Yang Q Kenny MK Harris CC Brosh RM 《Cancer research》2005,65(4):1223-1233
Werner syndrome is a hereditary disorder characterized by the early onset of age-related symptoms, including cancer. The absence of a p53-WRN helicase interaction may disrupt the signal to direct S-phase cells into apoptosis for programmed cell death and contribute to the pronounced genomic instability and cancer predisposition in Werner syndrome cells. Results from coimmunoprecipitation studies indicate that WRN is associated with replication protein A (RPA) and p53 in vivo before and after treatment with the replication inhibitor hydroxyurea or gamma-irradiation that introduces DNA strand breaks. Analysis of the protein interactions among purified recombinant WRN, RPA, and p53 proteins indicate that all three protein pairs bind with similar affinity in the low nanomolar range. In vitro studies show that p53 inhibits RPA-stimulated WRN helicase activity on an 849-bp M13 partial duplex substrate. p53 also inhibited WRN unwinding of a short (19-bp) forked duplex substrate in the absence of RPA. WRN unwinding of the forked duplex substrate was specific, because helicase inhibition mediated by p53 was retained in the presence of excess competitor DNA and was significantly reduced or absent in helicase reactions catalyzed by a WRN helicase domain fragment lacking the p53 binding site or the human RECQ1 DNA helicase, respectively. p53 effectively inhibited WRN helicase activity on model DNA substrate intermediates of replication/repair, a 5' ssDNA flap structure and a synthetic replication fork. Regulation of WRN helicase activity by p53 is likely to play an important role in genomic integrity surveillance, a vital function in the prevention of tumor progression. 相似文献
54.
A new antibacterial antibiotic was produced (136.5 microg/ml) using a 5 L EYELA Fermenter using 2 L fermentation medium at temperature: 27 degrees C, pH: 7.2, agitator speed: 200 rpm, aeration rate 1 vvm having KLa 251.74 hr(-1) at 96 hrs. The optimised conditions for antibiotic using washed cells of the selected strain are pH: 7.2, temperature: 27 degrees C, age of the biomass: 72 hr, amount of washed cell: 4 g in 50 ml normal saline, incubation time 72 hr. The antibacterial activity of the fermented broth was also examined against some bacterial species and it was found that it is active against gram positive as well as gram negative bacteria. 相似文献
55.
Herein we present a case of a bronchogenic cyst masquerading as a thyroid mass. Bronchogenic cysts are rare congenital malformations
that result from an abnormal development of the ventral foregut during organogenesis. They are commonly asymptomatic lesions
rarely found in the neck. In our case, a young male presented with complaints of neck discomfort over a long period presumed
to be secondary to a thyroid mass based on imaging studies. Fine needle aspiration was inconclusive. Post-operative pathological
sectioning revealed evidence of a bronchogenic cyst. These lesions have a low incidence of malignancy, and complete surgical
excision has been recommended. 相似文献
56.
Bhattacharyya P 《The Indian journal of surgery》2011,73(4):298-300
Carcinoid Tumours are classified as Neuro-endocrine tumours. Commonly known ulcerogenic neuro-endocrine tumour is Gastrinoma of the Pancreas and Duodenum.It secretes hormone Gastrin which causes hyperplasia of the gastric parietal cells with excessive secretion of hydrochloric acid resulting in multiple ulcerations in the stomach, duodenum and upper jejunum. Carcinoid tumours is not known to cause peptic ulceration. 相似文献
57.
58.
Chokkalingam Kavitha Annamalai MalarvizhiSatyanarayanan Senthil Kumaran Mathan Ramesh 《Food and chemical toxicology》2010
The impact of acute and sublethal toxicity of arsenate on hematological, biochemical and enzymological parameters of an Indian major carp Catla catla were estimated. The median lethal concentration of sodium arsenate to the fish Catla catla for 96 h was found to be 43.78 mg/L. During acute treatment (43.78 mg/L), hemoglobin (Hb), hematocrit (Ht), red blood cell count (RBC), white blood cell count (WBC), plasma glucose, plasma protein, liver aspartate and alanine aminotransferase (AST and ALT) levels decreased, whereas corpuscular indices like mean cell volume (MCV), mean cell hemoglobin (MCH) and mean cell hemoglobin concentration (MCHC) increased in arsenate treated fish. In sublethal treatment (4.378 mg/L), Hb, Ht, RBC, plasma protein levels decreased while MCHC and plasma glucose levels increased throughout the exposure period. A biphasic trend was noticed in WBC, MCV, MCH, liver AST and ALT levels. The alterations of these parameters can be effectively used as a rapid method to assess health of fish exposed to arsenate in the aquatic environment. 相似文献
59.
S Sudharsanam S Swaminathan A Ramalingam G Thangavel R Annamalai R Steinberg K Balakrishnan P Srikanth 《African health sciences》2012,12(2):217-225
Objectives
Study was conducted to assess whether temporal variation exists in airborne microbial concentrations of a hospital ward (west-Chennai, India) using active and passive methods, and characterise the microorganisms.Methods
Air samples (duplicates) were collected simultaneously using exposed-plate, impingement (BioSampler) and filtration (personal sampling filter cassette loaded with gelatin filter) methods over different periods of the year. Bacterial plates were incubated at 37°C and observed for growth after 48h; fungal plates were incubated at 25°C and 37°C and observed upto 7 days. Microorganisms were identified using standard microbiological procedures.Results
Microbial loads were found to vary with the sampling method. Concentrations of bacteria were higher (exposed-plate: 45–150 CFU/plate; impingement: 1.12E+03–1.6856E+05 CFU/m3; filtration: 3.788E+03−1.91111E+05 CFU/m3) than fungi (exposed-plate: 0–13 CFU/plate; impingement: 0–3.547E+03 CFU/m3; filtration: 0–1.515E+04 CFU/ m3). Coagulase-negative Staphylococci and Micrococci were the predominant Gram-positive cocci in active and passive samples. Enterobacter and Pseudomonas were the predominant Gram-negative bacilli. Among fungi, Aspergillus niger was isolated throughout the year. There was no significant temporal variation in airborne microbial loads irrespective of methods.Conclusions
Exposed-plate method was found to capture microorganisms efficiently with little variation in duplicate samples, suggesting its use in hospitals for preliminary assessment of indoor air quality and determine pathogenic microorganisms due to particle fall-out. 相似文献60.