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91.
The growth-inhibitory effects of combining interferons (IFN) with platinum(II) complexes were tested with the aim of comparing these in cultures of estrogen-receptor(ER)-negative MDA-MB231 and ER-positive MCF-7 breast cancer cell lines. Another aim was to test whether IFN as a biological response modifier could enhance the effect of the Pt complexes in vitro in an attempt to find an explanation for their more potent antitumor effects in in vivo models. Here it is shown that in both cell lines the combinations of different IFN with all three Pt complexes generally resulted in additive growth inhibition, as calculated by the product of the fraction of surviving cells obtained with each compound alone. Moreover, in MCF-7 cells natural IFN (nIFN) combined with aqua[meso-1,2-bis-(2,6-dichloro-4-hydroxyphenyl)ethylenediamine]sulfatoplatinum(II) (meso-6-Pt) resulted in synergistic inhibition. This synergy could be attributed to the estrogenic property of meso-6-Pt, since the ligand and estradiol also enhanced the inhibitory effect of nIFN. In contrast, the combination of recombinant IFN and meso-6-Pt was antagonistic in MDA-MB231 cells. These results show that, in spite of the similar responses of the ER-negative and ER-positive cells to each compound alone, these cells show unexpected differences in their sensitivity to combinations of IFN and the new Pt complex meso-6-Pt.Abbreviations ER estrogen receptor - IFN interferon(s) - nIFN natural interferon - rIFN recombinant interferon - meso-4-Pt aqua[meso-1,2-bis(2,6-difluoro-3-hydroxyphenyl)ethylenediamine]sulfatoplatinum(II) - meso-6-Pt aqua[meso-1,2-bis-(2,6-dichloro-4-hydroxyphenyl) ethylenediamine]sulfatoplatinum(II)  相似文献   
92.
For noninvasive evaluation of anatomy and flow characteristics of internal mammary artery graft (IMA-graft), 2D echo-Color-Doppler (CDE) was performed in 60 patients (54 M, 6 F, mean age 54.1±6.9 y), who underwent coronary angiography 20.1 ±13 months after a coronary artery bypass graft (CABG).CDE was performed, using an echocardiographic unit equipped with a 5 MHz linear transducer.In all patients, measurements of IMA-graft diameter (mm), and peak systolic and diastolic flow velocity (cm/sec) were obtained at baseline and also in 16 patients after dipyridamole infusion (0.54 mg/Kg/min) and in 10 patients after sublingual nitroglycerin (NTG) (0.4 mg). Angiography showed the IMA-graft patency in 58/60 patients (96.8%).A typical biphasic flow was displayed by CDE in 49/58 patients (84.4%) with angiographic patency.Dipyridamole infusion increased both IMA-graft diameter and peak diastolic flow velocity (PDFV) from 2.28 ±0.51mm to 2.9 ±0.42mm and from 19.4 ±6.2 cm/sec to 93.9 ±29 cm/sec, respectively (p<0.0001).No significant modifications of peak systolic flow velocity (PSFV) were observed.NTG increased PDFV from 29.11 ±8 cm/sec to 41.88 ±7.20 cm/sec (p<0.005), while diameter and PSFV showed no statistically significant modifications.CDE is a useful diagnostic tool for noninvasive evaluation of IMA-graft patency both early after surgery and during long-term follow-up. CDE pharmacological stress improves the sensibility of the technique and it can provide indirect information about pathophysiology of recipient coronary vessel.  相似文献   
93.
To measure regional skeletal kinetics using fluorine-18 fluoride positron emission tomography (PET) it is necessary to know the concentration of radioactive tracer being delivered to bone by arterial plasma with relation to time, the arterial input function (IFa). Methods by which IFa can be derived without arterial sampling are attractive because of their relative technical simplicity and the reduction in possible morbidity to the subject. We have compared the use of a scaled population input function (IFp) and a corrected image-derived input function from the aorta (IFi) with an IFa directly measured from a radial artery line in ten normal postmenopausal women. Both of the aforementioned methods rely only on a small number of discrete venous samples. Each subject had a dynamic PET acquisition of the lumbar spine performed after the intravenous injection of 180 MBq 18F-fluoride. Both the IFp and the IFi were compared with the IFa in terms of the accuracy of determination of six parameters. These were: plasma clearance of fluoride to bone mineral (K i), unidirectional plasma clearance to total bone tissue (K 1) and individual rate constants k 2, k 3 and k 4, calculated using non-linear regression with a three-compartment model, and the plasma clearance to bone mineral calculated using the Patlak method (K pat). For both the IFp and the IFi method the root mean square errors for K pat and K i were similar and small (<8.2%). The errors in determining K 1 and the rate constants k 2 to k 4 are larger by either method, but with a small advantage using the IFp method. It is concluded that the use of either non-invasive method for determining the arterial plasma input function is suitable for the measurement of the most important parameters, K i and K pat, in these subjects. Received 8 April and in revised form 11 July 1999  相似文献   
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Metacarpal and phalangeal lengths were measured on 1290 hand radiographs of Nigerian children, aged 3–16 years. The radiographs were obtained during a combined cross-sectional and longitudinal study of growth and development. There is a linear increase in tubular bone length with age in both sexes. The girls have higher values for all the bones up to the age of 13 years when the boys overtake them. Comparison of our data with those from North American children shows that the values amongst Nigerian children are higher than White, Black American and Mexican American children. Of particular note is the difference between Black American and Nigerian figures. It is postulated that the decreased metacarpophalangeal lengths in Black Americans compared with Nigerians may be due to gene dilution.  相似文献   
97.
A Th2 cytokine pattern has recently been reported both in allergic and nonallergic chronic rhinosinusitis in asthmatic children. The aim of the study was to evaluate the cytokine pattern in chronic rhinosinusitis in allergic and nonallergic asthmatic children before and after medical treatment. Thirty asthmatic children were evaluated, 18 males and 12 females (mean age 9.1 years). Sixteen were allergic and 14 were nonallergic. All children were asthmatic and suffered from chronic rhinosinusitis, whose diagnosis was confirmed by endoscopy. All of them were treated with amoxicilline-clavulanate (20 mg/kg b.i.d.) and fluticasone propionate aqueous nasal spray (100 µg daily) for 14 days; a short course of oral corticosteroid was also prescribed (deflazacort 1 mg/kg daily for 2 days, 0.5 mg/kg daily for 4 days and 0.25 mg/kg daily for 4 days). Rhinosinusal lavage and nasal cytology were performed in all subjects before and after medical treatment. IL4 and IFNγ were measured by immunoassay and inflammatory cells were counted by conventional staining. Thirteen allergic children and 12 nonallergic children showed a negative endoscopy after the treatment. Allergic subjects showed a significant decrease of IL4 (p = 0.0002) and a significant increase of IFNγ (p = 0.03) after the treatment. Nonallergic children showed a significant decrease of IL4 (p = 0.0007) and a nonsignificant increase of IFNγ. A significant reduction of the inflammatory infiltrate was detected in all asthmatic children (p < 0.05). This study confirms a Th2 polarization in chronic rhinosinusitis both in allergic and nonallergic asthmatic children. Moreover, the medical treatment of chronic rhinosinusitis reversed the cytokine pattern from a Th2 towards a Th1 profile both in allergic and nonallergic children.  相似文献   
98.
This proof of principle study aimed to define a new and simple strategy for detection of endometrial cancer using epigenetic markers. We investigated DNA isolated from vaginal secretion collected from tampon for aberrant methylation of five genes (CDH13, HSPA2, MLH1, RASSF1A, and SOCS2) using MethyLight in 15 patients with endometrial cancer and 109 patients without endometrial cancer. All endometrial cancer patients revealed three or more methylated genes, whereas 91% (99 of 109) of the patients without endometrial cancer had no or fewer than three genes methylated in their vaginal secretion. The methods developed in this study provide the basis for a prospective clinical trial to screen asymptomatic women who are at high risk for endometrial cancer.  相似文献   
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