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101.
BACKGROUND: Reverse total shoulder arthroplasty provides a surgical alternative to standard total shoulder arthroplasty for the treatment of selected complex shoulder problems. The purpose of the present study was to evaluate the effects of etiology on the results of reverse total shoulder arthroplasty. METHODS: Between May 1995 and June 2003, 240 consecutive reverse total shoulder arthroplasties were performed in 232 patients with an average age of 72.7 years. Patients were grouped according to etiology, and the clinical and radiographic outcomes for each group were measured and compared. RESULTS: One hundred and eighty-six patients with 191 retained reverse total shoulder arthroplasty prostheses were followed for an average of 39.9 months. Overall, the average Constant score improved from 23 points before surgery to 60 points at the time of follow-up and 173 of the 186 patients were satisfied or very satisfied with the result. Although substantial clinical and functional improvement was observed in all etiology groups, patients with primary rotator cuff tear arthropathy, primary osteoarthritis with a rotator cuff tear, and a massive rotator cuff tear had better outcomes, on average, than patients who had posttraumatic arthritis and those managed with revision arthroplasty. Dislocation (fifteen cases) and infection (eight cases) were the most common complications among the 199 shoulders that were followed for two years or were revised prior to the minimum two-year follow-up. Patients who received the reverse prosthesis at the time of a revision arthroplasty had a higher complication rate than did those who received the reverse prosthesis at the time of a primary arthroplasty. CONCLUSIONS: The reverse total shoulder arthroplasty prosthesis can produce good results when used for the treatment of a number of other complex shoulder problems in addition to cuff tear arthropathy. Patients with posttraumatic arthritis and those undergoing revision arthroplasty may have less improvement and higher complication rates in comparison with patients with other etiologies. The advanced age of the patients in the present series and the relatively short duration of follow-up suggest that the prosthesis should continue to be used judiciously.  相似文献   
102.
BACKGROUND: The influence of the preservation solution used for in situ perfusion of the donor and pancreas storage on islet isolation has received little attention. METHODS: In this prospective controlled trial, we compared the outcome of human islet isolation from pancreata perfused with University of Wisconsin (UW) solution or Celsior, an alternative colloid-free extracellular solution. RESULTS: At the 1-year interim analysis, the viability and insulin secretion of islets isolated from donors perfused with UW (n=19) or Celsior (n=5) were identical. However, total islet recovery (IEQ) and isolation yield (IEQ/g) were 1.8-fold and 2.1-fold inferior in the Celsior group (P<0.05 vs. UW). Overall, 13 (68%) of islet preparations were effectively transplanted from the UW group vs. none from the Celsior group (P=0.01). The clinical study was discontinued and the causes of these differences were further explored in the pig (n=14). In contrast to UW, Celsior induced cell swelling and pancreas edema after only four hours of cold storage. These abnormalities were delayed when the donor was perfused with Solution de Conservation d'Organes et de Tissus (SCOT), an extracellular solution containing polyethylene glycol. CONCLUSIONS: Our results suggest that colloid-free preservation solutions might be suboptimal for pancreas perfusion and cold storage prior to islet isolation and transplantation. Because pancreata are now frequently recovered for islet transplantation, preliminary experimental and clinical data about islet isolation should be obtained prior to the routine implementation of new preservation solutions for abdominal perfusion during multiorgan recovery.  相似文献   
103.

Purpose

Cup design has been incriminated as the source of groin pain after hip resurfacing but has not been well described; thus, it was assessed in a prospective study looking at three implant types.

Methods

A group-match was done between three groups of hip resurfacing devices according to age, sex, body mass index, activity level, osteoarthritis aetiology and pre-operative scores.

Results

The global groin pain rate was 5.7 % at six months and 2.7 % at last follow-up. Groin pain rate was significantly different between the three groups (p = 0.004) and had a strong influence on the subjective results (p = 0.04). No groin pain emerged between six months and last follow-up. No clinical differences were noted in Harris hip score and Merle d’Aubigné-Postel score at last follow-up. However, the Oxford hip score and Devane activity score were significantly lower for cups with macrostructures.

Conclusion

The low groin pain rate in this prospective cohort was probably secondary to the specific surgical technique used and seems to be correlated with cup design. Macrostructures on the external part of the cup could be significantly harmful.  相似文献   
104.

Background

Recently, we identified a gene signature of intrahepatic cholangiocarcinoma (ICC) stroma and demonstrated its clinical relevance for prognosis. The most upregulated genes included epithelial cell adhesion molecule (EpCAM), a biomarker of cancer stem cells (CSC). We hypothesized that CSC biomarkers could predict recurrence of resected ICC.

Methods

Both functional analysis of the stroma signature previously obtained and immunohistochemistry of 40 resected ICC were performed. The relationships between the expression of CSC markers and clinicopathologic factors including survival were assessed by univariate and multivariable analyzes.

Results

Gene expression profile of the stroma of ICC highlighted embryonic stem cells signature. Immunohistochemistry on tissue microarray showed at a protein level the increased expression of CSC biomarkers in the stroma of ICC compared with nontumor fibrous liver tissue. The overexpression of EpCAM in the stroma of ICC is an independent risk factor for overall (hazard ratio = 2.6; 95% confidence interval, 1.3–5.1; P = 0.005) and disease-free survival (hazard ratio = 2.2; 95% confidence interval, 1.2–4.2; P = 0.012). In addition, the overexpression of EpCAM in nontumor fibrous liver tissue is closely correlated with a worst disease-free survival (P = 0.035).

Conclusions

Our findings provide new arguments for a potential role of CSC on ICC progression supporting the idea that targeting CSC biomarkers might represent a promise personalized treatment.  相似文献   
105.

Background

The debate on the optimal number of prostate biopsy core samples that should be taken as an initial strategy is open.

Objective

To prospectively evaluate the diagnostic yield of a 21-core biopsy protocol as an initial strategy for prostate cancer (PCa) detection.

Design, setting, and participants

During 10 yr, 2753 consecutive patients underwent a 21-core biopsy scheme for their first set of biopsy specimens.

Intervention

All patients underwent a standardized 21-core protocol with cores mapped for location.

Outcome measurements and statistical analysis

The PCa detection rate of each biopsy scheme (6, 12, or 21 cores) was compared using a McNemar test. Predictive factors of the diagnostic yield achieved by a 21-core scheme were studied using logistic regression analyses.

Results and limitations

PCa detection rates using 6 sextant biopsies, 12 cores, and 21 cores were 32.5%, 40.4%, and 43.3%, respectively. The 12-core procedure improved the cancer detection rate by 19.4% (p = 0.004), and the 21-biopsy scheme improved the rate by 6.7% overall (p < 0.001). The six far lateral cores were the most efficient in terms of detection rate. The diagnostic yield of the 21-core protocol was >10% in prostates with volume >70 ml, in men with a prostate-specific antigen level < 4 ng/ml, with a prostate-specific antigen density (PSAD) <0.20 ng/ml per gram. A PSAD <0.20 ng/ml per gram was the strongest independent predictive factor of the diagnostic yield offered by the 21-core scheme (p < 0.001). The 21-core protocol significantly increased the rate of PCa eligible for active surveillance (62.5% vs 48.4%; p = 0.036) than those detected by a 12-core scheme without statistically increasing the rate of insignificant PCa (p = 0.503).

Conclusions

A 21-core biopsy scheme improves significantly the PCa detection rate compared with a 12-core protocol. We identified a cut-off PSAD (0.20 ng/ml per gram) below which an extended 21-core scheme might be systematically proposed to significantly improve the overall detection rate without increasing the rate of detected insignificant PCa.  相似文献   
106.
ObjectivesTo analyze to what extent partial nephrectomy (PN) is superior to radical nephrectomy (RN) in preserving renal function outcome in relation to tumor size indication.Methods and materialsClinical data from 973 patients operated at 9 academic institutions were retrospectively analyzed. Glomerular filtration rate (GFR) before and after surgery was calculated with the abbreviated Modification of the Diet in Renal Disease equation. For a fair comparison between the 2 techniques, all imperative indications for PN were excluded. A shift to a less favorable GFR group following surgery was considered clinically significant.ResultsMedian age at diagnosis was 60 years (19–91). Tumor size was smaller than 4 cm in 665 (68.3%) cases and larger than 4 cm in 308 (31.7%) cases. PN and RN were performed in 663 (68.1%) and 310 (31.9%) patients, respectively. In univariate analysis, patients undergoing PN had a smaller risk for developing significant GFR change following surgery than those undergoing RN did. This was true for tumors≤4 cm (P = 0.0001) and for tumors>4 cm (P = 0.0001). In multivariate analysis, the following criteria were independent predictive factors for developing significant postoperative GFR loss: the use of RN (P = 0.0001), preoperative GFR<60 ml/min (P = 0.0001), tumor size≥4 cm (P = 0.0001), and older age at diagnosis (P = 0.0001).ConclusionsThe renal function benefit carried out by elective PN over RN persists even when expanding nephron-sparing surgery indications beyond the traditional 4-cm cutoff.  相似文献   
107.
Mice were exposed by nose-only inhalation to 239PuO2, which resulted in an IAD of 1110 +/- 29 Bq. At various times after exposure, rates of collagen metabolism were measured using validated in vivo methods based on the administration of radiolabelled proline, together with a large flooding dose of unlabelled proline and measurement of its incorporation into lung collagen as hydroxyproline. Dramatic increases in both synthesis and degradation rates of collagen were observed. At 54 days after exposure the fractional synthesis rates in experimental mice were almost five times those in controls (control: 3.2 +/- 0.6%/day, 239PuO2-exposed: 14.5 +/- 0.4%/day) and by 300 days synthesis rates, although declining, were still more than double the control values. A similar pattern of change was observed for collagen degradation. The combination of changes in synthesis and degradation rates led to a 60% increase in lung collagen content by 300 days (control: 3.05 +/- 0.24 mg/lung, 239PuO2-exposed: 4.88 +/- 0.42 mg/lung). The data suggest that extensive remodelling of the lung connective tissue matrix occurs during development of fibrosis and that, over long periods of time, small imbalances between synthesis and degradation may result in quite large increases in protein content.  相似文献   
108.
MRI of portal cavernoma with biliary involvement   总被引:2,自引:0,他引:2  
PURPOSE: To assess the value of MRI in the diagnosis of portal cavernoma with biliary obstruction. MATERIAL: and methods: six patients referred for clinical suspicion of biliary obstruction and portal cavernoma were explored with MRI. all patients were explored using a signa 1.5 t GE MR unit, with high gradient field strength and torso phased array coil. Biliary ducts were explored with ss-fse sequences of MR-cholangiopancreatography (MRCP), coronal and oblique coronal 20mm thick slices. Then, coronal T2w with shorter TE eff, MR-angiography and delayed T1w sequences were performed. CT scan and sonographic examinations of the liver were performed in all patients. Two patients were operated on and 2 underwent endoscopic retrograde cholangiography. RESULTS: Three different types of biliary involvement were found: in 3 cases findings that mimic cholangiocarcinoma spreading along the common bile duct and in 3 other cases multiple smooth extrinsic impressions along the common bile duct; in one patient MRCP demonstrated an irregular narrowing of the common bile duct mimicking chronic cholangitis. In all cases, the bile duct varices appeared of low T2W signal; in three cases, fibrosis was identified on delayed sequences. CONCLUSION: MRCP and MR-angiography can be proposed as a first imaging study in patients with portal cavernoma and cholestasis or bile duct dilatation.  相似文献   
109.
PURPOSE: To determine whether the blood flow abnormalities frequently associated with arteriovenous malformations (AVMs) can alter functional magnetic resonance (MR) imaging evaluation of language lateralization and whether reorganization of language function occurs in patients with brain AVMs. MATERIALS AND METHODS: Eleven patients with left-hemisphere brain AVMs and 10 age-matched control subjects were examined with 1.5-T blood oxygen level-dependent (BOLD) functional MR imaging. Verbal fluency, sentence repetition, and story listening tasks were performed. The functional MR imaging laterality index in the frontal and temporal lobes was defined as the (L - R)/(L + R) ratio, where L and R are the numbers of activated pixels in the left and right hemispheres, respectively. Statistical analyses were performed with Wilcoxon signed rank, Fisher exact, and Kruskal-Wallis tests. RESULTS: Control subjects had left-sided language dominance, although symmetric pixel counts were observed in the frontal lobes in two subjects and in the temporal lobes in one subject. Six patients had left-sided language dominance similar to that observed in control subjects. Five of these patients had AVMs outside frontal or temporal language areas, without flow abnormalities. Five patients had abnormally right-sided asymmetric indexes (below mean control subject value - 2 SDs), which suggested language reorganization (P <.05). Results of Wada examination and/or postembolization functional MR imaging performed in two of these patients showed that the abnormal laterality indexes were at least partly due to severe flow abnormalities that impaired detection of BOLD MR imaging signal intensity. CONCLUSION: These data suggest that flow abnormalities may interfere with language lateralization assessment with functional MR imaging.  相似文献   
110.
Proton longitudinal and transverse relaxivities of Dy(DTPA)(2-) and Dy-DTPA bisamide derivatives (Dy(DTPA-BA): Dy-DTPA bisamide, Dy(DTPA-BEA): Dy-DTPA bisethylamide, Dy(DTPA-BnBA): Dy-DTPA bis-n-butylamide, and Dy(DTPA-BBMA): Dy-DTPA bisbismethylamide) were analyzed between 0.47 T and 18.8 T. Curie longitudinal relaxation was clearly observed at magnetic fields larger than 2.4 T, but the longitudinal relaxivities are limited by the fast rotation of the complexes. Rotational correlation times were separately assessed by deuterium relaxometry of the diamagnetic deuterated lanthanum analogs. Transverse relaxivity, which depends on the square of the magnetic field and on the residence time of the coordinated water molecule (tau(M)), was more than 7.5 times larger at 18.8 T and 310 K for Dy(DTPA-BA) and Dy(DTPA-BEA) as compared to Dy(DTPA)(2-). This difference is mainly related to the slower water exchange of the bisamide complexes, as confirmed by the values of tau(M) measured by oxygen-17 relaxometry. Such Dy-complexes, characterized by relatively long tau(M) values (tauM310 larger than 100 ns but smaller than 1 micros), thus appear to be useful as negative T(2) (or transverse) contrast agents for high-field imaging. This was demonstrated by the spin-echo images of phantoms obtained at 4.7 T on samples containing Dy(DTPA)(2-) and Dy(DTPA-BEA).  相似文献   
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