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31.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
32.
Based on extensive clinical and clinical chemical information (107 different items) from 1002 jaundiced patients, we developed a diagnostic algorithm which was evaluated on a test sample of another 110 jaundiced patients. A primary classification into categories of obstructive jaundice (probability of obstruction greater than or equal to 0.80), non-obstructive jaundice (probability of obstruction less than or equal to 0.20), and of doubtful causes of jaundice (probability of obstruction: 0.20-0.80) was attempted. Among 234 patients in the data base who were classified as obstructive, 220 (94%) proved to be so, as did 36 (97%) of 37 in the test sample. The corresponding figures for non-obstructive jaundice were 463 (96%) of 483 patients correctly classified in the data base and 47 (92%) of 51 patients in the test sample. Altogether 69% of the patients in the data base and 75% of those in the test sample were correctly classified, in 27% and 20% the cause of jaundice was doubtful, and only 4% and 5%, respectively, were misclassified. A slight majority of the patients in whom the algorithmic diagnoses were doubtful proved obstructive. A close correlation was found between the preliminary diagnoses made by the algorithm and by the clinicians. A secondary classification of the patients by the algorithm into benign versus malignant causes of obstructive jaundice performed equally well in the data base and the test sample.  相似文献   
33.
The aim of these investigations was the development of stationary phases for GPC compatible with fluorinated solvents. The properties of crosslinked copolymers of 4-(2-heptafluoropropoxy-1, 2,2-trifluoroethoxy)styrene ( 1 ) were investigated in dependence of the mode of synthesis. Divinylbenzene (DVB) was used as crosslinking agent. In the case of homogeneously crosslinked gels, 1 mol-% of DVB results in a gel with an exclusion molecular weight of 2000. Heterogeneous crosslinking copolymerization of 1 with DVB in presence of inert diluents results in gels with exclusion limits from 5000 to 4000000 in dependence of the diluent composition. Characterization of the gels in GPC experiments was carried out with 2-(1,2-dibromotrifluoroethoxy)-1,1,2,3,3,3-hexafluoro-1-(perfluoropropoxy)propane (PPVE2Br2), hexafluorobenzene, 1,1,2-trichlorotrifluoroethane (FrigenR113) and trifluoromethylbenzene as eluents.  相似文献   
34.
Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ≥ grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading.  相似文献   
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38.
deShazo  RD; Daul  CB; Andes  WA; Bozelka  BE 《Blood》1985,66(4):993-998
Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity.  相似文献   
39.
Background: To describe the long‐term outcomes of trabeculectomies performed at Dunedin Hospital and followed in the Otago Glaucoma Surgery Outcome Study. Methods: Prospective non‐comparative case series of 841 eyes of 607 patients who had first trabeculectomies for primary open‐ or closed‐angle glaucoma at Dunedin Hospital between 1976 and 2005 and followed for a mean of 7.5 years (standard deviation 6.0). Results: The probability of a trabeculectomy controlling the intraocular pressure at 21 mmHg or less at 1, 10 and 20 years was 0.96 (95% confidence interval [CI] 0.95, 0.97), 0.86 (95% CI 0.83, 0.89) and 0.79 (95% CI 0.74, 0.83), respectively. Visual acuity was maintained or improved between preoperative assessment and final follow up in 68% of cases. The probability of not being blind following trabeculectomy at 1, 10 and 20 years was 0.98 (95% CI 0.96, 0.98), 0.83 (95% CI 0.80, 0.87) and 0.70 (95% CI 0.64, 0.76), respectively. The proportion of those with glaucomatous field loss increased during follow up from 16% (44/283) at 0–5 years to 50% (10/20) for those with 21 or more years of follow up. A repeat drainage procedure was required in 65 eyes (8%) (56 Molteno implant insertions and 9 repeat trabeculectomies). Conclusions: Intraocular pressure was well controlled by trabeculectomy; however, a steady decline in intraocular pressure control, visual acuity and visual field occurred during follow up.  相似文献   
40.
Five of the six families with the Berardinelli Seip syndrome in Norway cluster in six adjacent rural municipalities of south-western Norway. The six patients from this area were born between 1951 and 1973, none between 1974 and 1995. The absence of new cases may be explained by a decrease in the intraregion marriage rate and inbreeding. Genealogical investigations show that the mutation must have occurred at least 400 years ago. The sixth family was clinically different and geographically sporadic from a Finnish-descent rural East Norwegian population. A genetic linkage study of all six families revealed fresh crossovers versus the disease allele in nine DNA marker systems and the absence of recombination in three (maximum lod score + 1.3). None of the last showed allelic association. These families are included in an international effort to map the CLBS locus. The patients have been included in the homozygosity testing of totally 28 patients in an international collaborative study. The three patients, assumed identical in descent from both parents, were jointly homozygous in none of the 250 dinucleotide markers tested. A heterochromatic 9qh + segregated from one parent in two families.  相似文献   
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