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1.
This paper reports a method of acquiring and codifying branching profiles of axonal arborizations. Using a microcomputer interfaced with a motor driven microscope scanning stage, an acquisition strategy was developed. This strategy allows large profiles (covering up to 1250 mm2) to be measured with an accuracy of a few microns. Each histological section is associated with a specific coordinate system. This system was found to locate the profiles with high precision and reliability in the x-y microscope stage. The overall tracing accuracy of the system is fully discussed.  相似文献   
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Grazzi  L.  Usai  S.  Bussone  G. 《Neurological sciences》2007,28(2):S134-S137
Neurological Sciences - Chronic headaches have increasingly become a focus within the field of head pain. Most patients with frequent headache eventually overuse their medications, and when it...  相似文献   
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Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism.  相似文献   
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Holmium:YAG laser ureterolithotripsy   总被引:17,自引:0,他引:17  
OBJECTIVE: To report on the experience obtained in the treatment of a series of 150 cases of ureteral stone disease by means of the holmium:yttrium-aluminum-garnet (Ho:YAG) laser. METHODS: One hundred and fifty consecutive cases treated by means of Ho:YAG laser ureterolithotripsy have been reviewed in order to assess the results. In 81 cases the stones were located in the lower third, in 47 in the medium third, and in 22 cases in the upper third of the ureter. The laser was set at a power of 8-10 W and at a frequency of between 6 and 10 Hz. Thin ureteroscopes were selected, such as the 7-Fr Gautier or the new ultrathin 4.8-Fr Wolf instrument. In some cases other ureteroscopes were chosen. RESULTS: Lasertripsy was effective in every kind of stone, allowing fragmentation into portions measuring at most 4 mm (largest diameter) or disintegration. The clearance rate of the stones was 92.6% during the 30-day follow-up period. Calcium dihydrate stones were of course more easily broken than monohydrate ones. No damage to the ureter was observed following the vaporization which is produced by this kind of laser, since particular attention was paid to avoid any contact between the laser beam and the ureteral mucosa. In some instances ureteroscopic maneuvering provoked some slight lacerations. In a few cases accidental contact of the laser beam with the ureteral mucosa produced extremely small coagulations of no immediate or postoperative relevance. CONCLUSIONS: The Ho:YAG laser constitutes an effective instrument for the fragmentation of any kind of ureteral stone; it allows the use of thin or ultrathin instruments and, if manipulated with care, does not damage the ureteral mucosa or the ureteral wall.  相似文献   
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Despite the high probability of cure of patients with acute promyelocytic leukemia (APL), mechanisms of relapse are still largely unclear. Mutational profiling at diagnosis and/or relapse may help to identify APL patients needing frequent molecular monitoring and early treatment intervention. Using an NGS approach including a 31 myeloid gene-panel, we tested BM samples of 44 APLs at the time of diagnosis, and of 31 at relapse. Mutations in PML and RARA genes were studied using a customized-NGS-RNA panel. Patients relapsing after ATRA-chemotherapy rarely had additional mutations (P = .009). In patients relapsing after ATRA/ATO, the PML gene was a preferential mutation target. We then evaluated the predictive value of mutations at APL diagnosis. A median of two mutations was detectable in 9/11 patients who later relapsed, vs one mutation in 21/33 patients who remained in CCR (P = .0032). This corresponded to a significantly lower risk of relapse in patients with one or less mutations (HR 0.046; 95% CI 0.011-0.197; P < .0001). NGS-analysis at the time of APL diagnosis may inform treatment decisions, including alternative treatments for cases with an unfavorable mutation profile.  相似文献   
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OBJECTIVE: To evaluate the usefulness of a commercial serological enzyme immunoassay (EIA) for detecting salivary immunoglobulin (Ig) G to Helicobacter pylori. DESIGN: Prospective, multicentre study. SETTING: The study was conducted at 11 gastroenterology hospital centres throughout Italy. PARTICIPANTS AND INTERVENTIONS: Two hundred and thirteen dyspeptic patients underwent gastroscopy with antral biopsies. At each centre, two of the following three tests for H. pylori diagnosis were performed: urease quick test, histology, and 13C-urea breath test. Samples of unstimulated saliva and venous blood were collected from each patient. Salivary and serum H. pylori IgG were determined with the EIA Helori-test IgG (Eurospital, Trieste, Italy). MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values, and accuracy of the salivary and serum EIAs. RESULTS: By using a receiver operating characteristic curve, salivary EIA yielded 81% (95% confidence interval 73-87%) sensitivity, 73% (62-83%) specificity, 84% (76-90%) positive predictive value, 69% (58-79%) negative predictive value, and 78% (72-84%) accuracy. At the cut-off suggested by the manufacturer, serum EIA had 90% (84-95%) sensitivity, 78% (67-86%) specificity, 88% (81-93%) positive predictive value, 82% (71-90%) negative predictive value, and 86% (81-91%) accuracy. CONCLUSION: In this large multicentre study, detection of salivary H. pylori IgG with a commercial serological EIA was a fairly accurate diagnostic method. Data confirm that saliva testing does not compare favourably with serology in the assessment of H. pylori status.  相似文献   
9.
Antral biopsies from 56 patients who underwent gastroscopy for upper gastrointestinal symptoms were studied by transmission electron microscopy. Campylobacter pylori was demonstrated in specimens from 39 patients. The bacteria were present in 3 of the 8 normal specimens and in 36 of the 48 cases with chronic gastritis. Electron microscopy showed that organisms were located deep the mucous layer in intimate relation with the luminar surface of the antral epithelium. No ultra-structural evidence was found to suggest bacterial invasion of the mucosa or phagocitic ingestion by neutrophils. Our results indicate a close correlation between active inflammation and Campylobacter pylori.  相似文献   
10.
Handedness has been linked to an enhanced risk of alcohol abuse, while less is known about other drugs. A convenience sample of 1004 male and female Italian participants (females=58%) from the general community (18 to 65 years old: average age = 30; standard deviation = 10, median = 25) was asked about: handedness (preference in writing); lifetime use of alcohol, tobacco, and illicit drugs; levels of psychological distress, as measured by the General Health Questionnaire (GHQ); and levels of delusion proneness, as measured by the Peters et al. Delusions Inventory (PDI). Overall, 92 individuals (9.2%) were classified as left-handed, with no significant difference reported among genders. Lifetime use of illicit drugs, primarily cannabis, was reported by 20% of the sample. In a multiple logistic regression analysis, after taking into account sex, age, and caseness on GHQ and PDI, left-handed people in the sample were statistically more likely to report lifetime experimentation with heroin, ecstasy/amphetamine, and, marginally, hallucinogens, but not alcohol or tobacco. Different mechanisms might contribute to an explanation of greater lifetime experimentation with some illicit drugs among left-handed people as compared to right-handed people. However, replications with clinical samples are necessary before any definitive statements can be made.  相似文献   
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