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101.
Purpose. The purpose of this study was to determine the glass transition temperatures of new graft copolymers using Modulated Temperature Differential Scanning Calorimetry (MTDSC), and to assess the differences between starch and cellulosic derivatives of methyl methacrylate and between two different drying methods used in their preparation. Methods. Graft copolymers of methyl methacrylate were synthesized and dried by oven or freeze-drying. Surface area measurements and different thermal analysis techniques (Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA) and MTDSC) were used to characterize these copolymers. Results. DSC was not sensitive enough to identify the Tgs of the copolymers, however they were clearly identifiable by MTDSC. Tg values obtained may depend on the method of preparation that also altered their physical characteristics e.g. specific surface area. Cellulose derivatives showed lower Tgs than starch derivatives. The results also depended on the drying method used, thus, freeze dried products had slightly lower Tgs than oven dried products. Conclusions. MTDSC represents a useful thermal technique that allows the identification of glass transitions in these new copolymers with higher sensitivity and resolution than conventional DSC, separating the transition from overlapping phenomena such as decomposition or dehydration. The Tg of this new class of copolymers appeared to be dependent on polymer composition and drying method used.  相似文献   
102.
Steroid receptor analysis is the only widely accepted prognostic/predictive marker in breast cancer (BC) treatment. In the present study we evaluated the prognostic role of ER/PgR with p53 and Bcl2, in a series of 277 BC (153 pN1/2, 122 pNO, 2 pNx) with a long-term follow-up (67 months for DFS, 75 months for OS). Our results, besides confirming the usefulness of ER immunohistochemical expression as a prognostic marker, showed that PgR expression alone had a borderline/not significant prognostic value in the whole series (p=0.08 for DFS and p=0.09 for OS), while showed to be prognostic in N+ cases (p=0.02 for DFS and p=0.03 for OS). PgR prognostic value, however, was not independent at the multivariate analysis. By combining ER with PgR, p53 and Bcl2, we showed that ER/p53 and ER/Bcl2 phenotypes had a better discriminant role than ER/PgR phenotype. The ER+/p53+ phenotype was at higher risk of relapse/death as compared with ER+/p53- phenotype. Conversely ER-/p53+ phenotype showed the most unfavourable prognosis. Similar results could be observed concerning ER/Bcl2 phenotypes. Our study showed that the combined evaluation of ER/PgR weakly enhanced the prognostic/predictive power of ER status alone. On the contrary, the combined evaluation of ER/p53 and ER/Bcl2, improved this prognostic/predictive capability and allowed the separation of ER positive and ER negative cases into subgroups with different prognosis.  相似文献   
103.
The ferritins present in the first day human colostrum and mature milk were compared with serum and tissue ferritins on the basis of their iron content, immunological reactivity and glycosylation. Both had a low iron content. The degree of glycosylation and immunochemical properties of colostrum ferritin showed strong similarities with serum ferritin. The isoelectric points and immunochemical properties of milk ferritin were similar to heart ferritin. The concentration of colostrum ferritin was more significantly correlated to body iron stores than milk ferritin.  相似文献   
104.
OBJECTIVE: In 1994 we mailed questionnaires to referral centers in Italy in order to evaluate the different opinions concerning aspects of endometrial cancer treatment, which is still controversial. The data processing showed a significant nonhomogeneity in disease management and prompted the Italian Society of Gynecologic Oncology to define guidelines for endometrial cancer adjuvant treatment. In 2001, we mailed again the same questionnaire to the same referral Centers in Italy. The aim of the second enquiry was the evaluation of changes in endometrial cancer management and the effective impact of the guidelines published. METHODS: The enquiry used the same questionnaires mailed in 1994; actually, we mailed those questionnaires to the same referral centers in Italy twice: in December 2000 and March 2001.The results of both the enquiries were collected in a relational data base, and the statistical evaluations were calculated using SPSS-statistics (Window ver. 8). RESULTS: Endometrial cancer treatment consists in abdominal hysterectomy and bilateral salpingo-oophorectomy. The unique relevant difference as to 1994 consists in the systemic performing of peritoneal cytology in endometrial cancer staging. Unlike the previous enquiry, adjuvant radiotherapy is not systematically performed in disease at stage Ic because of the substantial absence of confirmed data demonstrating a real benefit in terms of survival rate.The comparison between the two enquiries shows a significant change in medical planning and diversification attitude according to patient age and menopausal state. The disease management changes in patients over 75 years old, mainly with respect to surgery and primary therapy. CONCLUSIONS: We noted a resistance of many centers to accept some trends actually widespread in the literature but not yet performed in practical clinical.  相似文献   
105.
106.
Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.  相似文献   
107.
Introduction: Endometrial cancer is the most common malignancy of the female genital tract in industrialized countries. The traditional treatment of endometrial cancer is based on a surgical approach. In recent years, systemic endocrine therapy has demonstrated good efficacy in recurrent or metastatic setting, delaying progression, ameliorating quality of life and palliating symptoms.

Areas covered: Phase I and II studies on selective estrogen receptor down-regulators used for the treatment of endometrial cancer treatment have been reviewed. The pharmacokinetic and pharmacodynamic features of selective receptor down-regulators have been also investigated.

Expert opinion: Selective estrogen receptor down-regulators may exhibit clinical efficacy in the treatment of gynecological malignancies due to their pure estrogen receptor antagonist properties. However, up to now data are still limited and some unsolved questions remain. Fulvestrant has poor oral bioavailability and low pharmacodynamic characteristics. Further trials are required to examine new selective estrogen receptor down-regulator agents with better pharmacodynamic and pharmacokinetic profiles.  相似文献   

108.
BACKGROUND AND OBJECTIVE: Anthracyclines are highly effective and widely used cytotoxic agents, but their application is often limited by cumulative dose-dependent cardiotoxicity. Dexrazoxane has been shown in several clinical trials to prevent the development of this serious toxicity. The aim of our study was to analyze the incidence of cardiac dysfunction over a 10-year period in patients with breast cancer who were treated with anthracycline-based regimens with addition of dexrazoxane, mainly in an adjuvant setting. METHODS: We conducted a retrospective analysis on a population of women with breast cancer treated at our institution between January 1993 and October 2003. We reviewed patients' medical records and data on patient characteristics, treatment history, and adverse events that were collected, starting from the time of first visit before starting therapy, with the use of software created and designed for clinical records management in our institution (1999 OK-DHtrade mark). Patients underwent an ECG assessment prior to starting chemotherapy, and were clinically monitored for cardiac failure. Those who developed signs and symptoms suggestive of cardiac dysfunction underwent further ECG. If clinical findings indicated, echocardiography and further cardiologic investigations were performed. The main outcome measure was the development of signs and symptoms indicative of congestive heart failure (CHF). RESULTS: A total of 318 female patients were treated with an anthracycline (doxorubicin or epirubicin)-based combination chemotherapy regimen during this time, in most cases in the adjuvant setting (n = 285). Most patients (n = 302) had early-stage disease and only 16 women presented with metastatic disease with good life expectancy (at least 1 year). All patients received dexrazoxane 1000 mg/m(2) intravenously prior to anthracycline administration during each chemotherapy cycle. The median follow-up duration was 35 months. During this time, five patients (1.57%) developed signs and symptoms of CHF. No patient at our institution died of heart failure during the period analyzed. Dexrazoxane was well tolerated, with no reports of adverse events associated with this drug. CONCLUSIONS: The reported incidence of cardiotoxicity in this study represents a marked reduction compared with historical data for patients receiving anthracycline-based chemotherapy without dexrazoxane. Dexrazoxane appears to have a cardioprotective effect in women with early-stage or advanced breast cancer treated with anthracycline-based combination chemotherapy, mainly as an adjuvant treatment. Prospective, randomized, controlled clinical trials in adjuvant setting should be performed to confirm these results.  相似文献   
109.

Purpose

To study the gluten metabolism in healthy individuals and its effect over the intestinal microbial activity.

Methods

The faeces of eleven healthy subjects were analysed under 4 diet regimens: their normal gluten diet, a strict gluten-free diet (GFD), a GFD with a supplemental intake of 9 g gluten/day and a GFD with a supplemental intake of 30 g gluten/day. Gluten content, faecal tryptic activity (FTA), short-chain fatty acids (SCFAs) and faecal glutenasic activity (FGA) were analysed in faecal samples.

Results

Faecal gluten contents, FTA, SCFAs and FGA varied significantly with different levels of gluten intake in the diet. When high gluten doses (30 g/day) were administered in the diet, SCFA concentrations (70.5 mmoles/kg faeces) were significantly different from those from the GFD period (33.8 mmoles/kg faeces) of the experiment. However, the FTA showed significant differences between the GFD (34 units) and the normal gluten-containing diet (60 units) and also between the GFD and the GFD + 30 g of gluten/day (67 units). When gluten was present in the diet, gluten was detected in the faeces, showing that at least a portion of the gluten ingested is eliminated in the large intestine, providing a substrate for intestinal microbial proteases. We have also shown the presence of faecal glutenasic activity that increased proportionally with the gluten intake in the diet, showing an enzymatic activity of 993 units in DSG, 2,063 units in DSG + 9 g and 6,090 units in DSG + 30 g.

Conclusions

The activity of the intestinal microbiota is modified by gluten intake in the diet. The incorporation of gluten in the diet increases the activity of a gluten proteolytic activity in the faeces.  相似文献   
110.
No validated models in Europe are capable of simulating the environmental fate of pesticides under the specific conditions of rice fields. Rice water quality--vadose zone flow and transport (RICEWQ-VADOFT) is a model developed from the coupling of a surface runoff model (RICEWQ) and a vadose zone flow and transport model (VADOFT) for determining predicted environmental concentrations in paddy water and sediment, runoff, and groundwater. This study is intended to evaluate the capability of this model to simulate effectively the environmental fate of the herbicide pretilachlor in the paddy environment. A two-year field study conducted in a representative rice-cultivated area of northern Italy provided measured concentrations of pretilachlor in paddy water and sediment and also a limited number of observations on runoff losses. The model successfully predicted the water balance in the paddy field in both years. After limited calibration, the model predicted the fate of pretilachlor in paddy water and sediment with high accuracy. Agreement between predicted and measured concentrations of pretilachlor in both years was assessed statistically using several statistical indicators. For example, modeling efficiency (EF) values of 0.867 to 0.935 and 0.702 to 0.718 in paddy water and sediment, respectively, document the strong agreement between predicted and measured pesticide concentrations. The model predictions showed high agreement with the limited amount of measured runoff data in 2002. The model predicted that no significant amounts of pretilachlor would leach below the top 25 cm of the soil, although no measured data were available to evaluate the predicted results. A sensitivity analysis of the model to variables controlling pesticide partitioning to paddy sediment (VBIND, depth for direct partitioning of pesticide to bed sediment; VMIX, mixing velocity by molecular diffusion) revealed that the predictions of pesticide leaching were influenced strongly by those variables. Generally the RICEWQ-VADOFT model is a useful modeling tool for pesticide risk assessment in rice paddies.  相似文献   
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