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101.
102.
The amounts of vanillylmandelic acid (VMA), homovanillic acid(HVA), and catecholamines (adrenalin, noradrenalin, and dopamine)in 24-hr urine specimens of 10 infants with neuroblastoma detectedthrough mass screening in Sapporo City (patient group) werecompared with those of 24 healthy infants (control group). The ages of the infants of both groups ranged from 6 to 11 months,which agrees with the age when mass screening is performed. For VMA and HVA, the mean value plus two or three times thestandard deviation of the control group clearly separated thetwo groups in the units of mg/day, /µg/mg of creatinine,mg/kg/day, and mg/m2/day. The cut off values of 24 /µg/mg of creatinine for VMAand 25 µg/mg of creatinine for HVA are now being usedby us for assaying 24-hr urine specimens. No significant difference was found between the groups in levelsof catecholamines, but their data were thought to be usefulas normal values, since few published data regarding their normalvalues are available.  相似文献   
103.
Congenital amegakaryocytic thrombocytopenia (CAMT) is an uncommon disorder in newborns and infants, characterized by isolated thrombocytopenia and megakaryocytopenia in the first year without physical anomalies. The defect of thrombopoiesis is not well understood. Recently, thrombopoietin (TPO), the ligand for the c-mpl receptor, was cloned. Accumulating evidence from in vitro and in vivo studies indicate that TPO plays a key role in the regulation of megakaryocytopoiesis. In this study we examined the effect of TPO on megakaryocyte colony formation from a patient with CAMT using a plasma-containing methylcellulose clonal culture. The in vitro results demonstrated a defective response to TPO in megakaryocyte colony formation from bone marrow mononuclear cells (MNC) of the patient, although interleukin-3 (IL-3) but not stem cell factor (SCF) induced only a small number of megakaryocyte colonies. These findings indicated that thrombocytopenia in CAMT could not be corrected by administration of TPO in vitro. Additionally, clonal cultures containing SCF, IL-3, IL-6 and erythropoietin showed decreased numbers of erythroid and myelocytic progenitors in the bone marrow of the patient. The serum TPO level measured by enzyme-linked immunosorbent assay was significantly higher than that in healthy controls. By PCR, marrow MNC from healthy children and from a patient with essential thrombocytosis expressed c-mpl mRNA, whereas no c-mpl mRNA was detected in marrow MNC from the patient with CAMT. There was no difference in the CD34 expression and c-kit mRNA between the CAMT patient and healthy children. The results of this study suggest that the pathophysiology in CAMT may be a defective response to TPO in haemopoietic cells through impaired expression of c-mpl mRNA.  相似文献   
104.
Abstract— Saiboku-To is an anti-asthmatic herbal remedy which consists of ten herbal extracts. To investigate the clinical relationship between the effects and chemical components of Saiboku-To, a simple and sensitive high-performance liquid chromatographic method (HPLC) for determination of magnolol, one of the major urinary products, was developed. Organic solvent extraction of urinary magnolol was conducted by diatomaceous earth column rapid-flow fractionation using ethanol/dichloromethane (8/92, v/v). Recovery rates of magnolol were more than 99% with coefficient of variations less than 6% in the concentration range 9·7–970 ng mL?1. Subsequent HPLC determination of magnolol was achieved using a conventional silica-gel column, a mobile phase mixture of acetic acid/diethyl ether/n-hexane (0·2/17·0/82·8, v/v), and a UV-absorption detector set at 290 nm. Calibration was on the basis of peak height ratio between magnolol and flavone as an internal standard. The method was used to demonstrate excretion profiles of magnolol in healthy and asthmatic subjects following single administration of Saiboku-To.  相似文献   
105.
A new approach to enzymatic peptide synthesis by using aminoacyl-tRNA synthetase (ARS) as a catalyst has been investigated. Four ARSs (AspRS, HisRS, LeuRS and TyrRS) have been purified from a thermophilic bacterium, Bacillus stearothermophilus. By using TyrRS as a catalyst, tyrosine and leucinamide were shown to be condensed in the presence of ATP to give tyrosylleucinamide. In this manner, all of the ARSs investigated catalyzed the peptide synthesis reactions. TyrRS did not have strict specificity for the amino acid derivatives used as substrates and even D-amino acids were incorporated into peptides fairly easily in this enzymatic reaction. Preparative scale synthesis of L-Tyr-L-LeuNH2 was carried out and from this the scope and limitation of this new enzymatic reaction as a tool to the peptide synthesis has been described.  相似文献   
106.
Flow cytometry (FC) is widely utilized in the diagnosis of lymphoma and the light chain ratio (LCR) is especially useful in the diagnosis of B‐cell malignancy. In this study we analysed, retrospectively, the predictive value of the LCR in the diagnosis of B‐cell lymphoma in 105 consecutive patients with persistent lymph node enlargement or extranodal masses who underwent biopsy. We used a receiver‐operating characteristic curve to establish a LCR threshold value of 2.0. The specificity, sensitivity, positive and negative predictive values were 92.3%, 73.1%, 90% and 77%, respectively. We concluded that determination of LCR is a useful adjunct to pathological diagnosis.  相似文献   
107.
BACKGROUND: Phylogenetic analysis has been used widely to characterize extraintestinal pathogenic Escherichia coli in molecular epidemiological studies. We have recently reported a putative pathogenicity island (PAI), carrying uropathogenic-specific protein (usp) and a unique mosaic structure of small open reading frames following usp, providing four subtypes of PAIusp classified from their sequential patterns. METHODS: A total of 427 E. coli isolates from uncomplicated urinary tract infections (194 cystitis, 76 pyelonephritis, and 107 prostatitis) and 50 fecal isolates were examined for phylogenetic grouping and PAIusp subtyping as well as the prevalence of virulence factors (VF) and O serogroups. RESULTS: Both phylogenetic group B2 and usp-positive strains were equally predominant in cystitis, pyelonephritis and prostatitis (B2, 80.9%, 86.8%, and 86.9%; usp, 79.4%, 93.4%, and 88.8%, respectively). Furthermore, each PAIusp subtype was shown to be closely associated with several VF genes as well as several common O serogroups of uropathogenic E. coli. CONCLUSIONS: In molecular epidemiological studies, PAIusp subtyping will provide additional informative findings of E. coli strains belonging to phylogenetic group B2.  相似文献   
108.
AIM: Vardenafil is a highly selective phosphodiesterase type-5 inhibitor for the treatment of erectile dysfunction (ED). Efficacy of vardenafil has been demonstrated in various ED populations, but that in Japanese patients with spinal cord injury (SCI) has not been assessed. METHODS: This was an open-label, multicenter, flexible dose, 12-week study in patients with ED due to SCI. Following a 4-week observation period, patients received vardenafil 10 mg for 4 weeks, and based on efficacy, tolerability and patient preference, doses for the remaining 8 weeks were decided by investigators. The primary efficacy parameter was erectile function domain score of the International Index of Erectile Function. RESULTS: Ten patients took 10 mg all through the study, while 22 patients took 20 mg after completing 4 weeks' treatment with 10 mg. The erectile function domain score increased from 12.2 at baseline to 25.0 at Last Observation Carried Forward (LOCF) in the former group and from 10.3 to 22.5 in the latter group, respectively. Importantly, there was a 5.0 point increase in erectile function domain score after up-titration in the latter group. Drug-related adverse events were observed in 22% of patients including hot flushes (9%) and headache (6%), but these were transient and mild in intensity. Serious adverse events and adverse events leading to discontinuation of the study drug were not reported. CONCLUSIONS: Vardenafil 10 and 20 mg was well tolerated and improved erectile function in patients with SCI. Of interest, erectile function was further improved by 20 mg in patients who were not sufficiently treated with 10 mg.  相似文献   
109.
Effects of three aminoglycoside antibiotics, amikacin (AMIK),tobramycin (TOB), and gentamicin (GM), on the auditory and vestibularfunctions were assessed in rats, the most frequently used speciesin toxicity studies. Chronic electrodes for auditory brainstemresponse (ABR) recording were implanted on the epidural surface,and those for post rotatory nystagmus (PRN) were implanted atthe nictitating membrane and the outer canthus. AMK, TOB, andGM were given intramuscularly twice daily for 3–4 weeksat a daily dose of 350, 150, and 100 mg/kg, respectively. Theamplitude of each wave of the ABR was decreased or disappearedin the groups treated with AMK, TOB, and GM. In the PRN, theduration of the nystagmus was decreased in the TOB group andcompletely lost in the GM group. No abnormality was observedin the PRN in the AMK group. These results were similar to thosereported in the ototoxicity studies of these drugs in guineapigs and indicate that ototoxicity can be evaluated in ratsas successfully as in guinea pigs by this procedure.  相似文献   
110.
Expression of thymidine phosphorylase in human superficial bladder cancer   总被引:9,自引:0,他引:9  
BACKGROUND: The purpose of the present paper was to investigate the expression level of thymidine phosphorylase (TPase) in superficial bladder cancer tissues obtained by transurethral resection, and determine whether its expression correlates with tumor recurrence. METHODS: From March 1998 to December 2001, 99 patients with superficial bladder cancer were diagnosed and treated at eight affiliated hospitals. Tissue specimens obtained by transurethral resection of superficial bladder cancer (TURBT) were applied to immunohistochemical study using anti-TPase antibody as well as pathological diagnosis. The data were subjected to statistical analysis. RESULTS: Using MoAb 654-1 as the primary antibody, TPase was clearly stained in human bladder cancer tissues. The maximum TPase level measured by enzyme-linked immunosorbent assay (ELISA) method in normal bladder tissues was 18.7 U/mg protein. The TPase activity was 2.8-fold higher in tumors than in normal bladder samples (P = 0.037). The TPase positivity rates determined by immunohistochemical and ELISA methods were distinctly correlated (P = 0.046). For the recurrence-free rates in pT1 tumors treated by TURBT alone (n = 46), there were no statistically significant differences between Tpase-positive or -negative cases. CONCLUSIONS: The TPase expression determined by ELISA and immunohistochemistry is significantly up-regulated in superficial bladder tumors compared with normal bladder samples. However, TPase expression by immunohistochemistry is not a predictive index of recurrence-free rate for superficial bladder cancer treated with TURBT alone.  相似文献   
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