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OBJECTIVE: In an attempt to differentiate obstructive from non-obstructive dilation of the renal collecting system in children, a prospective clinical study was carried out. MATERIAL AND METHODS: During duplex Doppler sonography examination in 23 children resistive index (RI) and pulsatility index (PI) and RI ratio values before and after intraverous furasemide administration were compared with the findings obtained with diuretic renogram examination (t(1/2)). RESULTS: Evaluation of the results demonstrated that diuresis RI and PI determination may aid differentiation of severely obstructed renal units from those with slight (equivocal) or no obstruction. CONCLUSION: Kidneys with severe UPJ obstruction tended to have more elevated RI and PI values than the non-obstructed or equivocally obstructed ones. Again, determination of RIR values for each kidney showed the same elevation in severely obstructed kidneys, while non-obstructive or indeterminately obstructed ones demonstrated statistically insignificant changes.  相似文献   
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PURPOSE: Accurately estimating transition zone volume is important for the medical or surgical management of symptomatic benign prostatic hyperplasia and determination of prostate specific antigen density of the transition zone. We evaluated whether preoperative transrectal ultrasound measurements of the transition zone predict enucleated adenoma weight. MATERIALS AND METHODS: We measured transition zone volume preoperatively using transrectal ultrasound and the prolate ellipsoid method in 50 patients with presumed benign prostatic hyperplasia who underwent suprapubic prostatectomy. Transition zone volume corresponds to the adenoma. Enucleated adenoma weight was then correlated with preoperatively determined transition zone volume. RESULTS: As measured by transrectal ultrasound, mean transition zone volume plus or minus standard deviation was 80.88 +/- 37.42 cc (range 31 to 200). Mean enucleated adenoma weight was 68.70 +/- 36.26 gm. (range 18 to 180). There was a statistically significant correlation of estimated transrectal ultrasound volume of the transition zone with enucleated prostate adenoma weight (r = 0.95, p <0.001). However, when prostate adenoma weight was determined using the formula, prostate adenoma weight = -6.00 + 0.92 x transition zone volume, we noted a significant difference in mean prostate adenoma weight and mean transition zone volume (p <0.001). Since the regression coefficient of transition zone volume was significantly different from 1, we identified no agreement of prostate adenoma weight with estimated transrectal ultrasound volume of the transition zone. CONCLUSIONS: These data reveal a significant difference in mean prostatic adenoma weight and mean transition zone volume. Although transition zone volume measurements are well described, clear agreements on such measurements should be obtained to determine transition zone volume more precisely.  相似文献   
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Individual spermatozoa were assessed with pairs of probes for persistent histones and cytoplasmic retention, persistent histones and DNA fragmentation, and persistent histones and apoptotic markers. The individual spermatozoa were treated sequentially with combinations of probes for these cytoplasmic and nuclear biochemical markers. Sperm fields were recorded with computer-assisted imaging, and staining patterns with the two probes in the same spermatozoa were examined and scored as light, intermediate or dark (mature to arrested-maturity spermatozoa). The effects of arrested sperm maturation were similar with respect to the cytoplasmic and nuclear characteristics of spermatozoa in 84% of cells, indicating that cytoplasmic and nuclear attributes of arrested sperm maturation are related. However, there were moderate (intermediate-dark or intermediate-light patterns, 14.5% of cells) or major (light-dark patterns, 1.6% of cells) discrepancies in the intensity of the double staining patterns. Thus, testing with single maturity markers may not be fully reliable. These findings are important with respect to: (i) arrested sperm maturation; (ii) potential efficacy of antioxidant and similar therapeutic strategies in subfertile men, as spermatozoa with infrastructure defects due to mismaturation or maturation arrest are unlikely to respond to interventions; and (iii) detection of adverse male environmental exposures.  相似文献   
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This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity against Stapylococcus epidermidis. Silicone blocks (1 × 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was 63.307 μm in group 1, 111.538 μm in group 2, 43.076 μm in group 3, and 30.384 μm in group 4. The differences between groups 2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation.  相似文献   
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Summary One of the mechanisms of injury in varicocele has been proposed to be elevated nitric oxide (NO). We aimed to determine the association between the elevation of NO and lipid oxidation in varicocele compared with peripheral venous levels of these two substances as it has not been studied before. The study group consisted of 13 adolescents with left idiopathic varicocele of grades II-III. Blood specimens were obtained from dilated spermatic and peripheral veins simultaneously. Peripheral samples were also collected from 13 healthy children as controls. Nitrite/nitrate levels (NO(x)) and levels of malonedialdehyde (MDA) were determined using Griess reaction and thiobarbituric acid test, respectively. Results were compared with Kruskal-Wallis and Mann-Whitney tests. Peripheral NO(x) and MDA were the same in the study and control groups (p = 0.069 and p = 0.27, respectively). Spermatic vein NO(x) and MDA levels were elevated significantly compared with the peripheral levels in the study group (p = 0.005 and p = 0.048, respectively). Increased NO(x) levels with lipid oxidation occur locally in adolescent varicocele, implying that these events could be reversed by early treatment.  相似文献   
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The purpose of this study was to determine whether renal venous pulsations are affected by compression of the left renal vein (LRV) between the aorta and spine, and also to determine the clinical significance of incidentally detected retroaortic LRV. The study population was recruited from 783 consecutive patients undergoing abdominal CT examination for various indications. 22 patients with a retroaortic LRV were prospectively enrolled in this study, and 22 patients without renal disease served as a control group. After measuring the diameters of the central and peripheral portions of the LRV on CT images, the ratio (P/C) and difference (P-C) of the diameters were calculated. Doppler sonography of the interlobar arteries and veins of the left kidney was then performed to obtain impedance indices. Urine analysis of all subjects and scrotal colour Doppler ultrasound of male patients were also performed. The retroaortic LRV diameters were significantly narrower than the pre-aortic LRV diameters (p = 0.002). The left intrarenal venous impedance indices were significantly higher in the patients with retroaortic LRV (p = 0.026) and in the subgroups with P/C>2 (p = 0.020), with P-C>4 mm (p = 0.007) and without nutcracker-like associations (p = 0.006) than in control subjects, but no significant difference was noted between the arterial resistance indices. Haematuria (n = 8), proteinuria (n = 4), varicocele (n = 3) and collaterals (n = 1) were detected in the study group but not in the control group. In conclusion, incidentally detected retroaortic LRV appears to be associated with haematuria, proteinuria, varicocele and altered venous pulsatility. Further investigations are needed to understand the role of venous Doppler ultrasound in the nutcracker phenomenon.  相似文献   
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46,XX testicular disorder of sex development (46,XX TDSD) is a relatively rare condition characterised by the presence of testicular tissue with 46,XX karyotype. The present study aims to reveal the phenotype to genotype correlation in a series of sex-determining region Y (SRY)-positive 46,XX TDSD cases. We present the clinical findings, hormone profiles and genetic test results of six patients with SRY-positive 46,XX TDSD and give the details and follow-up findings of our three of previously published patients. All patients presented common characteristics such as azoospermia, hypergonadotropic hypogonadism and an SRY gene translocated on the terminal part of the short arm of one of the X chromosomes. Mean ± standard deviation (SD) height of the patients was 164.78 ± 8.0 cm. Five patients had decreased secondary sexual characteristics, and three patients had gynaecomastia with varying degrees. Five of the seven patients revealed a translocation between protein kinase X (PRKX) and inverted protein kinase Y (PRKY) genes, and the remaining two patients showed a translocation between the pseudoautosomal region 1 (PAR1) of X chromosome and the differential region of Y chromosome. X chromosome inactivation (XCI) analysis results demonstrated random and skewed XCI in 5 cases and 1 case, respectively. In brief, we delineate the phenotypic spectrum of patients with SRY-positive 46,XX TDSD and the underlying mechanisms of Xp;Yp translocations.  相似文献   
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