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91.
92.
BACKGROUND: CD23 antigen is a cell surface protein considered important in the differentiation of chronic lymphocytic leukemia (CLL) from other lymphoid leukemias. METHODS: To better clarify CD23 role as a diagnostic tool, the authors retrospectively evaluated clinical and laboratory features of 372 patients who were referred to M.D. Anderson Cancer Center with a diagnosis of CLL or B-cell chronic lymphoproliferative disease. RESULTS: Most of the patients (91%) were CD19+/CD5+. Only 6% of these CD19+/CD5+ patients were CD23-. Overall, CD23- patients had the worse prognostic features compared with CD23+ cases, including anemia (P = 0.03), massive splenomegaly (P = 0.000), high lactate dehydrogenase (P = 0.007), high beta2-microglobulin (P = 0.006), older age (P = 0.001), and male gender (P = 0.02). Surface immunoglobulin expression was moderate/strong in 19 (82%) patients, and FMC-7 was positive in 22 (96%) patients. None of the 13 patients tested for CD10 expressed the antigen. Based on morphology, of the CD23, 16 (70%) were diagnosed with mantle cell leukemia (MCL) was diagnosed in 16 (70%) CD23- patients, 3 (13%) with splenic marginal-zone leukemia, 3 (13%) with prolymphocytic leukemia (PLL) or PLL/CLL, and 1 (4%) with CLL. No cyclin D1 protein expression was noted by Western blot analysis in the one case that showed typical CLL morphology, and this patient did not require therapy. On the whole, the survival rate of CD23- patients was significantly worse than that of patients with CD23+. In contrast, 15 of 32 (49%) CD19+/CD5- patients were CD23-. CD23 negativity in this group was not associated with distinct clinical features or outcome. Eleven (73%) of these patients were classified as having splenic marginal-zone lymphoma and 4 as having follicular lymphoma. CONCLUSIONS: These data indicate that CD23 negativity is rare in typical B-cell CLL, and CD23 negativity in patients with CD19+/CD5+ is suggestive of mantle cell leukemia a more aggressive disease with poor response to conventional therapy in which newer chemotherapy regimens such as hyper-CVAD may be more effective.  相似文献   
93.
Casella R  Shariat SF  Monoski MA  Lerner SP 《Cancer》2002,95(12):2494-2499
BACKGROUND: The authors found previously that plasma levels of urokinase-type plasminogen activator (uPA) and its receptor (uPAR) were elevated in patients with bladder carcinoma and were associated with features of biologically aggressive disease. In the current study, they tested the hypothesis that elevated urinary levels of uPA and uPAR would predict the presence of bladder malignancy by comparing the performance of uPA and uPAR with the performance of bladder wash-out cytology in the noninvasive diagnosis of bladder tumors. METHODS: An enzyme-linked immunosorbent assay was used to compare levels of uPA and uPAR in urine that was collected before cystoscopy from 122 patients with bladder carcinoma and from 107 participants in a control group. Seventy-two patients had clinical Tis or Ta transitional cell carcinoma, and 50 patients had invasive disease (>or= T1); 85 patients had clinical Grade 1-2 tumors, and 37 patients had Grade 3 tumors. For cytology, only high grade was considered positive. RESULTS: Urinary levels of uPA and uPAR were higher in patients with bladder carcinoma compared with levels in the control group (P < 0.001 and P = 0.016, respectively). However, only uPA levels were elevated in patients with abnormal urinary cytology (P = 0.006). After controlling for cytology (odds ratio [OR], 10.182; 95% confidence interval [95%CI], 4.451-23.291; P < 0.001), uPAR (P for trend = 0.168), and age (P = 0.091), those in the highest quartile for uPA had an increased risk of bladder carcinoma compared with those in the lowest quartile (OR, 3.022; 95%CI, 1.295-7.054; P for trend = 0.031). CONCLUSIONS: The current findings suggest that urinary levels of uPA, but not uPAR, are related to the risk of bladder carcinoma. The study confirmed the central role of urinary cytology in the noninvasive diagnosis of bladder carcinoma.  相似文献   
94.
There are several reports regarding the efficacy of vitamin B6 in the treatment of tardive dyskinesia (TD). Vitamin B6 plays a key role in the synthesis of several neurotransmitters, including serotonin, dopamine, norepinephrine, and gamma-aminobutyric acid, all of which have been proposed to be involved in the development of TD. The purpose of this study was to examine whether there are special markers to distinguish long-term neuroleptic exposure patients who have TD from those patients who do not develop this side effect. In view of the pivotal role of vitamin B6 in the synthesis of all neurotransmitters believed to take part in the pathogenesis of TD, we decided to examine whether basal levels of vitamin B6 might explain the difference between these two groups. Such a finding could provide a predictive marker for vulnerable patients. The active metabolite of vitamin B6 is pyridoxal phosphate (PP). Pyridoxal phosphate blood levels were measured in 15 schizophrenic and schizoaffective patients with TD and compared with 15 patients without evidence of TD (matched by sex, age, smoking, and diagnosis). We found that, although patients in the TD group were exposed to neuroleptic drugs for significantly longer periods of time, there were no differences in serum PP levels between the groups. The reports of the effectiveness of vitamin B6 supplementation in the treatment of TD could therefore be explained by the assumption that central nervous system or intracellular vitamin B6 levels, which are involved in the pathogenesis of TD, are not the same as vitamin B6 peripheral serum levels. There is need for further studies, which will clarify the relationship between vitamin B6 and TD.  相似文献   
95.
AIMS: To develop multivariate nomograms that determine the probabilities of all-cause and bladder cancer-specific survival after radical cystectomy and to compare their predictive accuracy to that of American Joint Committee on Cancer (AJCC) staging. METHODS: We used Cox proportional hazards regression analyses to model variables of 731 consecutive patients treated with radical cystectomy and bilateral pelvic lymphadenectomy for bladder transitional cell carcinoma. Variables included age of patient, gender, pathologic stage (pT), pathologic grade, carcinoma in situ, lymphovascular invasion (LVI), lymph node status (pN), neoadjuvant chemotherapy (NACH), adjuvant chemotherapy (ACH), and adjuvant external beam radiotherapy (AXRT). Two hundred bootstrap resamples were used to reduce overfit bias and for internal validation. RESULTS: During a mean follow-up of 36.4 months, 290 of 731 (39.7%) patients died; 196 of 290 patients (67.6%) died of bladder cancer. Actuarial all-cause survival estimates were 56.3% [95% confidence interval (95% CI), 51.8-60.6%] and 42.9% (95% CI, 37.3-48.4%) at 5 and 8 years after cystectomy, respectively. Actuarial cancer-specific survival estimates were 67.3% (62.9-71.3%) and 58.7% (52.7-64.2%) at 5 and 8 years, respectively. The accuracy of a nomogram for prediction of all-cause survival (0.732) that included patient age, pT, pN, LVI, NACH, ACH, and AXRT was significantly superior (P=0.001) to that of AJCC staging-based risk grouping (0.615). Similarly, the accuracy of a nomogram for prediction of cancer-specific survival that included pT, pN, LVI, NACH, and AXRT (0.791) was significantly superior (P=0.001) to that of AJCC staging-based risk grouping (0.663). CONCLUSIONS: Multivariate nomograms provide a more accurate and relevant individualized prediction of survival after cystectomy compared with conventional prediction models, thereby allowing for improved patient counseling and treatment selection.  相似文献   
96.
The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital.  相似文献   
97.
OBJECTIVE: This report reviews the obstetric outcomes of women with multifetal pregnancy reductions who subsequently underwent elective amniocentesis. STUDY DESIGN: Five hundred eight patients underwent multifetal pregnancy reduction at our institution. Among these, 91 patients underwent subsequent elective amniocentesis. The obstetric outcomes of all 508 patients were followed up. By means of logistic regression we evaluated several variables to determine any association with loss rate: (1) the finishing number of fetuses, (2) the number of fetuses undergoing reduction (starting number of fetuses minus the finishing number of fetuses), (3) the gestational age at reduction, (4) the maternal age at reduction, and (5) the procedure protocol. We observed that the finishing number of fetuses, the number of fetuses removed, and the procedure protocol were significantly associated with pregnancy loss rate. Women who underwent subsequent amniocentesis were compared with those who did not undergo amniocentesis. By means of multivariate conditional likelihood analysis we stratified the two groups according to the previously mentioned significant variables to compare the pregnancy loss rates. RESULTS: Among patients who subsequently underwent elective amniocentesis the total uncorrected pregnancy loss rate was 9.0% and the early premature delivery rate was 4.5%. The number of fetuses removed, the finishing number of fetuses, and the procedure protocol were statistically significantly associated with the loss rate. The adjusted odds ratio relating amniocentesis to the pregnancy loss rate was 0.7 (95% confidence interval, 0.31.5; P =.3.) CONCLUSIONS:The uncorrected rates of pregnancy loss and of early premature delivery among patients with multifetal pregnancy reduction who underwent subsequent amniocentesis were comparable to those of patients with multifetal pregnancy reduction who did not undergo amniocentesis.  相似文献   
98.
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.  相似文献   
99.
100.
This paper explores the role of milk-based formulae in achieving four aspects of nutritional health in infants and toddlers: in the suckling, to mimic the amino acid metabolism and the faecal flora of a breast-fed baby; in the weanling, to achieve adequate protein intakes in later infancy and beyond and to achieve satisfactory haemoglobin concentrations in the early toddler years. Milk-based formulae have two roles in infant nutrition: as so-called breast milk substitutes and as a safety net during the weaning period; the latter role may be the more important.  相似文献   
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