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The normal urothelium is covered by a glycosaminoglycan (GAG) layer which acts as a barrier to the adhesion of crystals. Destruction of the GAG layer increases the number of adhered crystals, and it is therefore assumed that it promotes crystal growth and stone formation. Intravesical instillation of pentosanpolysulfate, an exogenous glycosaminoglycan, after destruction of this layer reduces the adhesion of crystals to the urothelium. Intramuscular administration of carbenoxolone sodium following the experimental destruction of the GAG layer increases the rate of healing of the layer and reduces the number of adhered crystals.  相似文献   
3.
Few effective regimens are available for patients with advanced multiple myeloma resistant to or relapsing after both alkylating agents and VAD. We treated 52 patients with advanced and refractory multiple myeloma with the combination of cyclophosphamide (3.0 g/m2) and etoposide (900 mg/m2) followed by GM-CSF at a daily dose of 0.125 mg/m2 until recovery of granulocytes. 42% of patients responded with a median time of 19 d for recovery of granulocytes to 0.5 x 109/1 and a 4% mortality rate. Eight responding patients received a second myeloablative treatment supported by either autologous bone marrow (six patients) or blood stem cells (two patients). The median survival time for all patients was 11 months and the median remission time for responding patients was 8 months. The combination of cyclophosphamide and etoposide provided an effective rescue treatment for many patients with advanced multiple myeloma resistant to conventional therapies. This programme also allowed early marrow or blood stem cell collection in support of subsequent myeloablative therapy for selected patients.  相似文献   
4.
The incidence, risk factors and prognostic factors for candidal infection were determined in a prospective study of 280 infected patients. Thirty-one (11%) patients were infected with Candida spp., sub-divided into 18 (58%) with C. albicans, and 13 (42%) with non-albicans spp. (six C. glabrata, three C. parapsilosis, and one each of C. krusei, C. tropicalis, C. guilliermondii and C. lusitaniae). Infection with Candida spp. was always associated with concurrent bacterial infection. By univariate logistic regression analysis, the degree of morbidity and the duration of mechanical ventilation were independent predictive factors for death, but infection with Candida spp., was not. Factors associated with Candida spp. infection were the degree of morbidity, intensive care unit length of stay, alterations of immune response, and the number of medical devices involved. By multivariate logistic regression analysis, the only independent risk factor for candidal infection was intensive care unit length of stay.  相似文献   
5.
BACKGROUND: Small series and retrospective studies have suggested that treatment with gemcitabine may be associated with pulmonary toxicity. However, a prospective evaluation of cancer patients treated with gemcitabine-based chemotherapy without neoplastic involvement of the thorax and without administration of radiotherapy has not been performed. PATIENTS AND METHODS: To investigate this issue, 41 consecutive patients receiving gemcitabine and carboplatin underwent prospective evaluation of lung function, which included pulmonary symptoms, pulmonary function tests, arterial blood gases and radiographic studies. Assessment was performed before and after completion of chemotherapy in all patients. Patients with a substantial decline in diffusion capacity for carbon monoxide (DLCO), defined as a drop of > or = 20%, were reassessed 2 months later. RESULTS: After chemotherapy, there were no significant changes in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, alveolar volume or total lung capacity. In contrast, there was a significant decline in DLCO (73 +/- 22 versus 67 +/- 24% predicted; P = 0.017) and in carbon monoxide transfer coefficient (KCO) (89 +/- 24 versus 80 +/- 24% predicted; P = 0.004). Arterial blood gases did not change following treatment. Ten of the 41 patients (24%) exhibited a substantial decline in DLCO, which, however, recovered within 2 months (DLCO at baseline, immediately after therapy and at 2 months after completion of treatment, 84 +/- 14, 58 +/- 16 and 77 +/- 17% predicted, respectively; P < 0.001; baseline DLCO versus DLCO at 2 months, P > 0.05). Four of the 41 patients (10%) experienced dyspnea, which was self-limiting, with the exception of one patient who developed interstitial lung fibrosis. Among the various risk factors examined, older age, female gender and lower baseline DLCO were associated with more profound changes in DLCO post-treatment. CONCLUSIONS: This prospective analysis showed that the combination of gemcitabine and carboplatin induces a significant, but reversible, decrease in diffusion capacity, which is mostly asymptomatic. Thus, this regimen is safe as regards clinically significant lung toxicity.  相似文献   
6.
BACKGROUND: Waldenstrom's macroglobulinemia (WM) is an unusual lymphoplasmacytoid lymphoma characterized by the presence of a serum monoclonal immunoglobulin M. Although several studies have evaluated possible prognostic factors of this disease, few have focused on the survival and prognosis of symptomatic patients after the initiation of treatment. PATIENTS AND METHODS: Our study included 122 previously untreated patients with a median age of 67 years who required systemic treatment. Multiple variables were analyzed for their prognostic value on survival after initiation of treatment using univariate and Cox regression multivariate analysis. RESULTS: The median overall survival was 106 months. Pretreatment factors associated with shorter survival were age >/=65 years, splenomegaly, B-symptoms (weight loss, fever or night sweats), hemoglobin <10 g/dl, platelets <100 x 10(6)/dl, albumin <3.5 g/dl and bone marrow lymphoplasmacytic infiltrate >/=50%. In the multivariate analysis, the two variables with independent prognostic value were age >/=65 years and hemoglobin <10 g/dl. Furthermore, we were able to divide our patients into three risk groups based on the presence of two, one or none of these two adverse prognostic factors. The median survival times in the high-, intermediate- and low-risk groups were 46 months, 107 months and 172 months, respectively (P <0.0001). DISCUSSION: Our findings suggest that advanced age and anemia appear to be the two dominant prognostic factors for survival after initiation of treatment in patients with WM. These two readily available parameters can stratify the patients into three distinct subgroups and may help the selection of appropriate treatment.  相似文献   
7.
PURPOSE: To investigate the possibility of measuring the gene-specific DNA damage after therapeutic exposure to nitrogen mustards and to examine its relationship with the clinical response. EXPERIMENTAL DESIGN: The kinetics of gene-specific monoadducts and interstrand cross-link formation/repair were measured in the p53 and N-ras genes. DNA extracted from human peripheral lymphocytes following in vitro exposure to melphalan or therapeutic exposure to melphalan or cyclophosphamide was used. RESULTS: When lymphocytes were treated in vitro with biologically relevant doses of melphalan, monoadducts accumulated rapidly in both p53 and N-ras genes, reaching maximal levels within 2 h, whereas the highest interstrand cross-link levels were found within 8 h. Thereafter, the adducts were repaired with half-lives of 14.5 +/- 0.3 h (p53) or 18.8 +/- 1.5 h (N-ras) for monoadducts and 12.4 +/- 0.8 h (p53) or 14.1 +/- 2.2 h (N-ras) for interstrand cross-links. Moreover, peak levels of monoadducts in both genes were observed 2 h after treatment in peripheral leukocytes from patients with multiple myeloma treated with high-dose i.v. melphalan, supported by autologous stem cell transplantation, whereas interstrand cross-links were maximal within 8 h. Of seven patients examined, the three who showed the least levels of DNA damage did not respond to the high-dose melphalan. CONCLUSIONS: This is the first report showing that it is feasible to measure gene-specific DNA damage in a readily accessible tissue of humans exposed to bifunctional alkylating drugs and to examine, at the level of the individual patient, the relationships between the induction/repair of cytotoxic DNA damage and clinical response or long-term complications.  相似文献   
8.
Because the outcome of patients with primary ovarian non-Hodgkin's lymphoma (NHL) is controversial, we retrospectively analyzed experience with adults seen at the University of Texas M. D. Anderson Cancer Center from 1974 to 1993. Patients were included if at least one ovary was pathologically involved, and if combination chemotherapy was used that must have included doxorubicin for intermediate grade histologies. We identified 15 patients who constituted 0.5% of all untreated NHL and 1.5% of untreated ovarian neoplasms that presented to our instutition during this time. One patient refused therapy, leaving 14 assessable for response. Nine patients had intermediate-grade, 5 had high-grade, and none had low-grade NHL. One ovary was involved in 4 patients, and both in 10, in 7 of whom additional sites were involved, including supradiaphragmatic nodes in 2. Four patients had AAS I and 10 had AAS IV. Favorable (0 or 1) and unfavorable (>1) IPI scores were seen in 5 and 9 patients, respectively. The complete remission rate for all patients was 64%, and 5-year survival and FFS for all assessable patients were 57 and 46%, respectively. We conclude that the complete remission rate and FFS of patients with ovarian NHL treated with appropriate chemotherapy appear to be similar to that of patients with other nodal NHLs. Further work is required to determine prognostic factors in ovarian NHL.  相似文献   
9.
Purpose: To evaluate the efficacy and safety of the docetaxel-cisplatin combination in patients with advanced non-small-cell lung cancer (NSCLC).Patients and methods: Chemotherapy-naïve patients with histologically confirmed, measurable stage IIIB or IV NSCLC, a World Health Organization (WHO) performance status of 0–2 and adequate bone marrow, renal, hepatic and cardiac function were eligible for the study. Patients received docetaxel (100 mg/m2) as an one-hour infusion on day 1 and cisplatin (80 mg/m2) as a 30-min infusion with appropriate hydration on day 2. Granulocyte colony-stimulating factor (G-CSF; 150 µg/m2 , SC) was given on days 3 to 13. Treatment was repeated every three weeks.Results: Fifty-three patients were enrolled (28 with stage IIIB and 25 with stage IV). One complete and 23 partial responses were observed (overall response rate (OR): 45%; 95% CI: 34.1%–61.8%). The response rate was 57% and 32% in patients with stages IIIB and IV disease (P = NS). The median time to progression was 36 weeks and the median survival 48 weeks; the one-year survival was 48%. Grade 3–4 neutropenia occurred in 23 patients, 15 of whom were hospitalized for neutropenic fever; two patients died of sepsis. Grade 2 neurotoxicity was observed in six patients and grade 3 in five patients; grade 3 fatigue occurred in seven patients, grade 3–4 mucositis in four patients and grade 3–4 diarrhea in six patients. Mild allergic reactions and oedema were observed in five and four patients, respectively. The median dose intensity was 30 mg/m2 /week for docetaxel and 24 mg/m2 /week for cisplatin, corresponding to 91% and 89% of the specified protocol doses, respectively.Conclusions: The docetaxel–cisplatin combination is an active regimen in advanced NSCLC, but hematologic toxicity remains high despite the prophylactic use of G-CSF.  相似文献   
10.
BACKGROUND: Irinotecan (IRI) and oxaliplatin (OXA) are effective in the treatment of colorectal cancer. Previously untreated patients with advanced colorectal carcinoma (CRC) were randomly assigned to receive IRI plus leucovorin (LV)/5-fluorouracil (5-FU), or OXA plus LV/5-FU in order to compare the response rates, time-to-tumor progression, overall survival rates, and toxicity profiles of these two agents. MATERIALS AND METHODS: From January 1999 to February 2002, 295 patients were randomized to receive either IRI/LV/5-FU or OXA/LV/5-FU. The treatment schedules consisted of weekly IRI 70 mg/m(2) or OXA 45 mg/m(2) plus LV 200 mg/m(2) followed immediately by intravenous bolus 5-FU 450 mg/m(2) for 6 weeks, followed by a 2-week rest period. Treatment was continued for up to four cycles or until disease progression, unacceptable toxicity or patient refusal. RESULTS: There were no significant differences between the study arms in the overall response rate (33% with IRI/LV/5-FU versus 32% with OXA/LV/5-FU based on responses demonstrated on a single evaluation; 23% with IRI/LV/5-FU versus 22.3% with OXA/LV/5-FU based on responses confirmed according to WHO criteria) median time to progression (8.9 versus 7.6 months), and median overall survival (17.6 versus 17.4 months). Toxicity profiles (grades 3 and 4) were similar in the IRI and OXA arms (diarrhea 12.3% and 9.8%, neutropenia 8.2% and 4.9%, and febrile neutropenia 1.4% and 1.4%, respectively), with the exception of grade 3 sensory neuropathy, which almost exclusively occurred in the OXA arm (0% versus 5.6%; P=0.003, Fisher's exact test). CONCLUSION: The IRI/LV/5-FU and OXA/LV/5-FU regimens demonstrated equally substantial efficacies and manageable toxicity profiles in the first-line treatment of patients with advanced CRC. However, IRI/LV/5-FU may be the preferable regimen to avoid significant neurotoxicity associated with OXA-LV/5-FU.  相似文献   
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