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OBJECTIVE: To document infection with HIV type 1 (HIV-1) group M non-B subtypes in individuals living in New York City. DESIGN: From October 1999 through April 2003, HIV-1-seropositive individuals were selected from 3 clinics in New York City based on having risk factors for infection with HIV-1 non-B subtypes. METHODS: HIV-1 RNA was extracted from plasma samples, and partial gag, pol, or env genes were amplified by PCR analysis. The infecting HIV-1 group M subtype was determined based on results of either heteroduplex mobility assay or sequencing and phylogenetic analysis. RESULTS: Ninety-seven subjects were enrolled in the study. Of the 97 subjects, 91 (94%) were selected based on having emigrated from a non-European country, while 6 (6%) were native United States citizens. Subtypes were successfully determined in 53 (55%) of the 97 plasma samples tested. The subtypes in 2 plasma samples were unclassifiable. HIV-1 infections were classified as those due to the following group M subtypes: A (n = 4; 7%), B (n = 12; 22%), C (n = 8; 15%), F (n = 2; 4%), CRF01_AE-like (n = 7; 13%), CRF02_AG-like (n = 19; 34%), an intersubtype recombinant form G/A (n = 1; 2%), and unclassifiable viruses (n = 2; 4%). CONCLUSION: This study reveals infection with a broad variety of HIV-1 group M subtypes mostly in the immigrant population of New York City as well as how several non-B subtypes are being introduced into the United States.  相似文献   
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The effect of pH on electronic spectra of MAI was investigated. The N-methylpyridium alpha-amidooxime iodide (MAI) in water solution is hydrolized to weak base with log K2H = 10.14. At low concentration in water solution the geometrical isomers are likely to exist, yielding 4 isosbestic points in UV spectrum. In syn isomer the lone electron pair of -NH2 group is probably blocked through intramolecular hydrogen bonding with oxime group. The effect of hydrogen ions concentration on spectra of watersolution of MAI was examined within range Ho = -3.87 to pH 12.97. Determined protolitic constants are as follows: log K1H(pKa) = 12.14 dissociation of oxime proton, log K3BH = 4.02 - protonation of -NH2 group in anti isomer, log K3AH = 1.62 protonation of -NH2 group in syn isomer, log K4H = -2.42 - protonation of oxime nitrogen or oxygen.  相似文献   
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IntroductionRecently introduced microUSB ultrasound probe, which can be connected to personal mobile device constitutes a new class of diagnostic pocket size imaging devices (PSID).The aim of this study was to assess the feasibility and clinical utility of real-time tele-echocardiography with the use such device.Material and methodsThe study group comprised 30 patients (18 men and 12 women; mean age: 54 ±14 years; mean body mass index: 27 ±6 kg/m2), admitted to various hospital departments (infectious diseases, internal medicine and cardiology). All patients underwent focused echocardiographic examination performed by an inexperienced operator using PSID and collaborating remotely in real-time with cardiologist by means of tele-consultation. Before commencing the examination, the operators underwent 1 h training in use of the PSID.ResultsIn most of patients PSID imaging provided sufficient diagnostic image quality. The dimensions of left ventricle, left atrium and the aorta obtained during the this examination showed good correlation with standard echocardiography (r = 0.89, r = 0.82, r = 0.92 respectively), but the correlation for TAPSE measurements was less pronounced (r = 0.52). The agreement in detection of pathologies (wall motion abnormalities, morphological and functional valvular abnormalities) between the tele-echocardiography and standard echocardiographic examination was good to very good (κ ranged from 0.648 to 0.823).ConclusionsPocket size imaging devices allows an inexperienced operator to perform a focused echocardiographic examination under a remote supervision of an experienced cardiologist. The introduction of new technology in the form of PSID with tele-echocardiography feature can revolutionize access to this imaging technique.  相似文献   
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We reported a new method dealing with the synthesis of novel pharmacologically relevant α-aminophosphonate derivatives via a lipase-catalyzed Kabachnik−Fields reaction with yields of up to 93%. The advantages of this protocol are excellent yields, mild reaction conditions, low costs, and sustainability. The developed protocol is applicable to a range of H-phosphites and organic amines, providing a wide substrate scope. A new class of α-aminophosphonate analogues possessing P-chiral centers was also synthesized. The synthesized compounds were characterized on the basis of their antimicrobial activities against E. coli. The impact of the various alkoxy groups on antimicrobial activity was demonstrated. The crucial role of the substituents, located at the aromatic rings in the phenylethyloxy and benzyloxy groups, on the inhibitory action against selected pathogenic E. coli strains was revealed. The observed results are especially important because of increasing resistance of bacteria to various drugs and antibiotics.  相似文献   
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(1) Background: The aim of this study was to assess the concentrations of selected elements in female patients with cancer of the reproductive organs, taking into account the stage of treatment. (2) Methods: The study sample consisted of 51 patients with advanced endometrial cancer and ovarian cancer, undergoing chemotherapy. The median age of the studied patients with endometrial cancer was 66.0 years (IQR: from 60.75 to 70.25), and with ovarian cancer―60.0 years (IQR: from 49.0 to 64.0). Each of the qualified women, after consent to participate in the study, had her blood drawn several times (before surgery, the first course of chemotherapy, the third course of chemotherapy, and the sixth course of chemotherapy) in order to determine serum levels of macro- and micronutrients (Na, Mg, Ca, Zn, P, Cu, Fe, Cd, Ni, and Sr). (3) Results: In the study group of patients with cancer of the reproductive tract, the concentrations of iron (<0.001), magnesium (0.038), sodium (0.014), and nickel (0.037) varied significantly over the course of the study. The analysis showed that the interaction between the stage of chemotherapy and the type of cancer had an effect on the concentrations of magnesium and cadmium (p < 0.05). (4) Conclusions: In the studied group of patients with ovarian and endometrial cancer, the applied chemotherapy significantly changed the concentrations of Fe, Na, and Ni, regardless of the type of tumor. Changes in Mg and Cd concentrations resulted from the interaction between the stage of chemotherapy and the type of cancer. The results of serum concentrations of selected elements in women with cancer of the reproductive organs may help understand the physiological changes resulting from the applied chemotherapy.  相似文献   
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The aim of the research was to evaluate the changes in the surface properties of five functional clothing materials with water-repellent finishes (including PFC-free finish) after 1, 5, and 10 washes with three detergents. A new approach to the interpretation of the water-repellent properties of textile materials is presented, based on two techniques, i.e., the spray test method and contact angle measurements. The results showed that washing materials with hydrophobic finishes can cause significant changes in their properties, which are mainly dependent on the composition and structure of the material, as well as the type of hydrophobic finish. The PFC-free finish is the least resistant to washing. For all materials with PFC finishes, the water repellency depends on the fluorine content on the surface and fabric topography. It was also found that increasing washing frequency resulted in a gradual decrease in water repellency. The loss of water repellency below an acceptable level (Grade 3) occurred after the fifth washing for all materials. Significant differences in the interpretation of the results of the spray test and contact angle measurements were observed. Using these methods separately provides information on the changes in the surface properties of the tested materials; however, their parallel application allows for obtaining complementary data, which is important for the proper interpretation of results.  相似文献   
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(1) Background: The literature emphasizes the role of many factors influencing the onset of eating disorders (EDs) and their mutual influence on each other. Therefore, this study aimed to evaluate and compare the prevalence of orthorexic behaviors in groups of health-related and non-health-related students in terms of their differential health behaviors—diet and physical activity levels. (2) The study included 300 individuals representing two equal groups of fields of study, which for the study were called the health-related field (HRF) and the non-health-related field (NRF). (3) Results: Based on the results of the dietary assessment, it was found that the best dietary model was characterized by the HRF group; in this group, 97.2% of students were characterized by a very good and good dietary mode. The NRF group, on the other hand, was dominated by a sufficient dietary mode for 64.4% of all cases in this group (94 people), while the dietary model marked as “good” was less popular, at 24.6% of this group (36 people). (4) Conclusions: Based on the cited self-research and information from the literature, it can be concluded that the problem of orthorexia is still a new issue at the level of social sciences, medical sciences, and health sciences. The psychometric tools used in this study allowed us to demonstrate the prevalence of the aforementioned eating disorders in the sample groups of students.  相似文献   
9.
Nanoindentations and the Raman spectroscopy measurements were carried out on the (001) surface of undoped and S-doped InP crystal. The samples were indented with the maximum load ranging from 15 mN to 100 mN. The phase transition B3→B1 was not confirmed by spectroscopic experiments, indicating a plastic deformation mechanism governed by dislocations activity. Increasing the maximum indentation load shifts and the longitudinal and transverse optical Raman bands to lower frequencies reveals a reduction in the elastic energy stored in the plastic zone right below the indentation imprint. Mechanical experiments have shown that a shift in Raman bands occurs alongside the indentation size effect. Indeed, the hardness of undoped and S-doped InP crystal decreases as a function of the maximum indentation load.  相似文献   
10.
The use of composite overlays to increase the fatigue life of notched steel samples is discussed in this paper. For such purposes, in the first set of studies, static and fatigue tests as well as the detailed analytical and numerical analyses for samples with double-lap joints were performed. Based on such studies, the shapes of the composite overlays were set. For a better understanding of the failure forms of the investigated adhesive joints, the experimental studies were monitored with the use of digital image correlation. In the second set of experimental studies, the static and fatigue tensile tests were performed for steel samples with a rectangular opening with rounded corners reinforced by composite overlays. The different shapes (square 45 × 45 mm and long stripes 180 × 15 mm) and composite materials (GFRP and CFRP) were used as overlays. The obtained improvement of fatigue life was in the range of 180–270% in the case of the rectangular overlays and 710% in the case of application of the overlays in the form of the long stripes. This was also confirmed by numerical analyses in which a reduction in the stress concentration factor from 2.508 (bare sample) through 2.014–2.183 (square 45 × 45 mm overlays) to 1.366 (overlays in the form of long stripes 180 × 15 mm) was observed.  相似文献   
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