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71.
The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported.  相似文献   
72.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
73.
74.
The nucleoside analogue decitabine can deplete the epigenetic regulator DNA methyltransferase 1 (DNMT1), an effect that occurs, and is saturated at, low concentrations/doses. A reason to pursue this molecular-targeted effect instead of the DNA damage/cytotoxicity produced with high concentrations/doses, is that non-cytotoxic DNMT1-depletion can cytoreduce even p53-null myeloid malignancies while sparing normal haematopoiesis. We thus identified minimum doses of decitabine (0·1–0·2 mg/kg) that deplete DNMT1 without off-target anti-metabolite effects/cytotoxicity, and then administered these well-tolerated doses frequently 1–2X/week to increase S-phase dependent DNMT1-depletion, and used a Myeloid Malignancy Registry to evaluate long-term outcomes in 69 patients treated this way. Consistent with the scientific rationale, treatment was well-tolerated and durable responses were produced (~40%) in genetically heterogeneous disease and the very elderly.  相似文献   
75.
T-cell large granular lymphocytic leukaemia (T-LGLL) is a chronic clonal lymphoproliferative disorder of cytotoxic T lymphocytes which commonly occurs in older patients and is often associated with autoimmune diseases. Among 246 patients with T-LGLL seen at our institution over the last 10 years, we encountered 15 cases following solid organ or haematopoietic stem cell transplantation. Here, we studied the clinical characterization of these cases and compared them to de novo T-LGLL. This experience represented a clear picture of the intricate nature of the disease manifestation and the complexities of several immune mechanisms triggering the clonal expansion.  相似文献   
76.
The relationship between chronic lymphocytic leukaemia (CLL) and qualitative/quantitative gammaglobulin abnormalities is well established. Nevertheless, in order to better understand this kind of connection, we examined 1505 patients with CLL and divided them into four subgroups on the basis of immunoglobulin (Ig) aberrations at diagnosis. A total of 73 (4·8%), 149 (10%), 200 (13·2%) and 1083 (72%) patients were identified with IgM monoclonal gammopathy (IgM/CLL), IgG monoclonal gammopathy (IgG/CLL), hypogammaglobulinaemia (hypo-γ) and normal Ig levels (γ-normal) respectively. IgM paraprotein was significantly associated with a more advanced Binet/Rai stage and del(17p)/TP53 mutation, while IgG abnormalities correlated with a higher occurrence of trisomy 12. Patients with any type of Ig abnormality had shorter treatment-free survival (TFS) but no significant impact affecting overall survival (OS) compared to those with normal Ig levels.  相似文献   
77.
78.

Introduction

The purpose of this study was to assess the effect of osteoarthritis on the outcome of arthroscopic anterior cruciate ligament (ACL) reconstruction, and to assess the effect of the procedure on the progression of osteoarthritis.

Material and methods

Forty-two patients, age above 40, presenting by symptomatic instability secondary to rupture of the ACL were enrolled in a prospective cohort study. Cases were divided into two groups according to the absence of osteoarthritic changes (group I, 19 patients) or presence of osteoarthritic changes (group II, 23 patients) in preoperative radiographs. ACL anatomic single bundle reconstruction by the anteromedial portal technique using hamstring autograft fixed by biodegradable interference fit screws was done for all patients, and a fixed postoperative rehabilitation protocol was applied. Data were recorded and statistical analysis of the preoperative, 1 year follow up, and final follow up (average 41 months in group I and 42 months in group II) results of both groups was conducted.

Results

The average patient age at the time of operation was 44.5 years in group I versus 46.4 years in group II. The follow-up median pain scores, ROM, modified Lysholm scores were significantly better in group I compared to group II. On the contrary, the difference between preoperative and 1 year postoperative scores and the percentage of improvement of the modified Lysholm score were significantly higher in group II. Deterioration of the radiographic grade of osteoarthritis in the final follow-up was declared in 15.8 % of patients of group I and in 21.7 % of patients of group II (P?=?0.71). Age, concomitant meniscus injury, and presence of preoperative arthritic changes, and cartilage defect had no statistically significantly effect on the success rate. Patients who had ACL reconstruction more than 2 years after injury and those with higher body mass index (BMI) had worse outcome than those who had earlier reconstruction and lower BMI.

Conclusion

Patients having preoperative mild to moderate arthritic changes will indeed benefit from ACL reconstruction at short term, although their overall functional outcome seemed to be inferior to the outcome of non-arthritic patients. However, osteoarthritic changes deteriorate over time in both groups especially when there is preoperative mild to moderate arthritic changes.  相似文献   
79.
80.

Background

Acute appendicitis is the most frequent abdominal disease and requires urgent surgery. At the present time, laparoscopic appendectomy is a well-accepted emergency procedure at most centers. In this study, we used a new spiral needle to facilitate the procedure, making it easy, minimally invasive, and cost effective.

Methods

The study included 70 patients of both sexes with acute appendicitis that was treated by laparoscopic appendectomy using a new spiral needle. These cases were treated at the General Surgery Department, Zagazig University, Egypt, from May 2012 to August 2013. In the procedure we used only two ports (a 10-mm port directly below the umbilicus for the camera and a 5-mm port at the left iliac fossa at the midclavicular line). The new spiral needle was used to hold the appendix during the procedure and was inserted into the right iliac fossa depending on the site of the appendix.

Results

The mean age of the patients was 27.3 years, mean operative time was 40 min, and mean hospital stay was 1.3 days. Ten patients (14 %) had minimal bleeding at the site of needle passage into the mesoappendix. Wound infection at the site of umbilical port occurred in four patients (5.7 %) postoperatively.

Conclusion

Laparoscopic appendectomy using our new spiral needle is easy, minimally invasive, and cost effective.  相似文献   
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