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1.
Potentialities of the flow cytornetry method in studies of the qualitative and quantitative composition of endometrial immunocompetent cells are demonstrated. The studied leukocyte populations are found to occur in negligible quantities in the endometrium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 1, pp. 68–71, January, 1994.  相似文献   
2.
Synthetic fragment of human interferon-2α (124th–138th amino acid residue, laboratory code 2438) inhibits the growth of B lymphocytes (Daudi cell line) in a dose-dependent manner. Radiolabeled peptide 2438 binds to specific receptors on the cell surface and competes with interferon-2α for the common binding sites. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 446–448, April, 1997  相似文献   
3.
In order to find out correlations between the structure of an external donor and the obtained polymer, the effects of different external donors on the activity and stereospecificity of the MgCl2/TiCl4 catalytic system in the bulk polymerization of 4-methyl-1-pentene (4MP) were carefully studied. Different silane compounds of the structure RnSi(OR')4-n (where: n = 1–3, R = alkyl/phenyl, R = alkyl) and Al(i-Bu)3 (TIBA) were used as external donors and cocatalyst, respectively. The effect of the donor/TIBA mole ratio on the activity and stereospecificity of the catalytic system was studied. Some major effects were observed for the three different external donors, namely, Me3Si(OMe), Me2Si(OMe)2, and Me3Si(OBu)3, in the 4MP polymerization process. It was observed that the effect of the external silane donor on the polymerization strongly depends upon the size of the alkoxy and hydrocarbon (alkyl/phenyl) groups which are attached to the silicon atom. A selective deactivation of the non-stereospecific centers, as well as a transformation of the non-stereospecific into isospecific centers, is assumed to occur. On the basis of the obtained results and literature data available for the propene polymerization, the concept of structural conformity between the ligand-surrounded active center and the monomer molecule was carried forward.  相似文献   
4.
A modified technique for handsewn anastomosis after abdominoperineal pull-through resection is described. The technique is a continuous locked modification of the Gambee suture. Simplicity, rapidity, reliability, and firmness are the advantages of this technique.  相似文献   
5.
ObjectiveWe evaluate presentation and outcome of patients with metastatic RCC to the gallbladder from our institution and published literature.MethodsPatients with a history of gallbladder metastasis from RCC were selected from our institution's prospective database. A systematic PubMed search was performed to identify articles describing patients with metastatic RCC to the gallbladder. The final cohort included 33 patients: 4 from our institution and 29 from 28 previously published cases. Survival analysis was conducted using log-rank Kaplan-Meier analysis.ResultsMedian patient age was 63 years and the majority of patients were male. Most patients were asymptomatic and diagnosed with gallbladder metastasis on imaging performed for surveillance or staging. The median time to gallbladder metastasis following nephrectomy was 4 years. Metastasis to the gallbladder occurred both synchronously (33%) and metachronously (67%). Of the patients with available histology, all had clear cell RCC (n = 28). Of all patients, 13 (39%) had metastasis only to the gallbladder, while 20 (61%) had additional sites of metastasis. The most common sites of additional metastasis were contralateral kidney (30%), pancreas (21%), lung (18%), adrenal (18%), and lymph nodes (9%). All patients underwent cholecystectomy. At a median follow up time of 1.5 years after cholecystectomy, 54% of patients had no evidence of disease, 14% were alive with metastasis, 23% had died from metastatic RCC, and 9% died from causes unrelated to their cancer.ConclusionGallbladder metastasis from RCC is a rare event that may occur synchronously or metachronously with most patients being asymptomatic. Clear cell carcinoma appears to be the primary pathology associated with gallbladder metastasis. High rates of bilateral RCC and pancreatic metastasis suggest novel associations in patients with RCC and gallbladder metastasis.  相似文献   
6.

Purpose

[18F]Fluciclatide is an integrin-targeted PET radiopharmaceutical. αvβ3 and αvβ5 are upregulated in tumor angiogenesis as well as on some tumor cell surfaces. Our aim was to use [18F]fluciclatide (formerly known as [18F]AH111585) for PET imaging of angiogenesis in melanoma and renal tumors and compare with tumor integrin expression.

Methods

Eighteen evaluable patients with solid tumors ≥2.0 cm underwent [18F]fluciclatide PET/CT. All patients underwent surgery and tumor tissue samples were obtained. Immunohistochemical (IHC) staining with mouse monoclonal antibodies and diaminobenzidine (DAB) was applied to snap-frozen tumor specimens, and additional IHC was done on formalin-fixed paraffin-embedded samples. DAB optical density (OD) data from digitized whole-tissue sections were compared with PET SUV80% max, and Patlak influx rate constant (K i) data, tumor by tumor.

Results

Tumors from all 18 patients demonstrated measurable [18F]fluciclatide uptake. At the final dynamic time-point (55 min after injection), renal malignancies (in 11 patients) demonstrated an average SUV80% max of 6.4?±?2.0 (range 3.8 – 10.0), while the average SUV80% max for metastatic melanoma lesions (in 6 patients) was 3.0?±?2.0 (range 0.7 – 6.5). There was a statistically significant difference in [18F]fluciclatide uptake between chromophobe and nonchromophobe renal cell carcinoma (RCCs, with SUV80% max of 8.2?±?1.8 and 5.4?±?1.4 (P?=?0.020) and tumor-to-normal kidney (T/N) ratios of 1.5?±?0.4 and 0.9?±?0.2, respectively (P?=?0.029). The highest Pearson's correlation coefficients were obtained when comparing Patlak K i and αvβ5 OD when segregating the patient population between melanoma and RCC (r?=?0.83 for K i vs. melanoma and r?=?0.91 for K i vs. RCC). SUV80% max showed a moderate correlation with αvβ5 and αvβ3 OD.

Conclusion

[18F]Fluciclatide PET imaging was well tolerated and demonstrated favorable characteristics for imaging αvβ3 and αvβ5 expression in melanoma and RCC. Higher uptake was observed in chromophobe than in nonchromophobe RCC. [18F]Fluciclatide may be a useful radiotracer to improve knowledge of integrin expression.  相似文献   
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9.

Background

Multifocal renal cell carcinoma (RCC) has been reported in up to 25% of all radical nephrectomy specimens. Modern imaging tends to underestimate the rate of multifocality. Recognition of multifocality before treatment may guide physicians and patients to the type of intervention and tailor long-term follow-up.

Objective

Our aim was to develop and assess preoperative nomograms to predict occult multifocal RCC.

Design, setting, and participants

We evaluated 560 consecutive patients undergoing radical nephrectomy for clinically localized suspected sporadic RCC between 2000 and 2008 in a tertiary center. Clinically manifest multifocal lesions were excluded. Logistic regression models were used to assess the potential risk factors of occult multifocality with and without pathologic variables that may be available with preoperative biopsy. Nomograms were developed and assessed for diagnostic properties.

Interventions

All patients underwent radical nephrectomy.

Measurements

Assessments of risk factors for occult multifocal RCC were obtained using regression models and nomograms.

Results and limitations

The incidence of occult multifocality was 7.9%. Significantly associated predictors of multifocality were male gender, family history of malignancy other than RCC, radiographic size of the lesion, histologic subtype other than clear cell, and Fuhrman grade IV. The two designed nomograms had 0.75 and 0.82 concordance indices, respectively.

Conclusions

Our data suggest that occult multifocal RCC is more frequently associated with small (2–4 cm) renal lesions. Male gender, family history of kidney cancer, histologic subtype, and grade are strongly associated with an increased risk of occult multifocal RCC. The developed nomograms had good predictive accuracy that was enhanced when combined with pathologic variables.  相似文献   
10.
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