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991.
An unusual case of multiple cerebral tuberculomas is reported. The patient, a 19-year-old woman, presented with a 6-month history of raised intracranial pressure and cerebellar symptoms. CT scan disclosed a conglomerate of several ring-enhancing lesions within the cerebellar vermis and another homogeneously enhancing mass against the right occipital horn. Solid and ring-enhancing lesions are the main mode of presentation of cerebral tuberculomas. Although the patient had no history of systemic tuberculosis, this diagnosis was considered highly probable in this geographic area and was confirmed by pathological examination of the cerebellar mass, the excision of which was considered necessary. Antitubercular medications led to complete regression of the associated occipital lesion, as demonstrated by sequential CT scan examinations.  相似文献   
992.
Qualitative research has a vast potential for understanding complex issues such as stuttering, and is becoming more common in that research field. The purpose of this article is to highlight the potential benefits of qualitative research in stuttering through exploration of four different research paradigms and their knowledge claims. Through this explanation, a case is built for the benefits of applying qualitative methods to stuttering research. Questions such as “how” a certain behavior or process take places, rather than just “if” a certain behavior or process takes place, are possible within the qualitative paradigm. It is concluded that future knowledge about stuttering and its treatment will be well served by applying the most appropriate investigative methods to it rather than by attempting to establish information with a restricted set of quantitative approaches.  相似文献   
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996.
Silver  AJ; Baredes  S; Bello  JA; Blitzer  A; Hilal  SK 《Radiology》1987,163(1):205-210
To distinguish opacification owing to inflammatory conditions (sinusitis) from that caused by nasomaxillary malignancy, computed tomography scans in 24 proved cases of sinusitis or tumor were reviewed for features related to sinus size, wall thickness, and character of bone erosion. An anatomic system was defined for classifying lesions according to the surface and type of bony involvement. In 12 cases of chronic maxillary sinusitis, the involved sinus was usually small and thick walled. The nasal surface of the involved sinus usually was eroded; often the orbital surface was eroded. The erosion was, however, short, irregular, and in the region of a normal dehiscence (semilunar hiatus or infraorbital canal) in all cases. The infratemporal surface was never eroded. In 12 cases of nasomaxillary neoplasia, the sinus was enlarged, one or more walls of the involved sinus being thinned and expanded. Bone erosion was present in all cases; erosion of the infratemporal surface was specific for neoplasia and significant as the usual site of recurrence.  相似文献   
997.
Vitamin D is an important factor in bone metabolism. Animal studies have shown a positive effect of vitamin D3 supplementation on fracture healing, but evidence from clinical trials is inconclusive. A randomized controlled trial was performed to assess the effects of vitamin D3 supplementation on fracture healing using HR-pQCT–based outcome parameters. Thirty-two postmenopausal women with a conservatively treated distal radius fracture were included within 2 weeks postfracture and randomized to a low-dose (N = 10) and a high-dose (N = 11) vitamin D intervention group receiving a 6-week bolus dose, equivalent to 700 and 1800 IU vitamin D3 supplementation per day, respectively, in addition to a control group (N = 11) receiving no supplementation. After the baseline visit 1–2 weeks postfracture, follow-up visits were scheduled at 3–4, 6–8, and 12 weeks postfracture. At each visit, HR-pQCT scans of the fractured radius were performed. Cortical and trabecular bone density and microarchitectural parameters and microfinite element analysis–derived torsion, compression, and bending stiffness were assessed. Additionally, serum markers of bone resorption (CTX) and bone formation (PINP) were measured. Baseline serum levels of 25OHD3 were <50 nmol/L in 33% of all participants and <75 nmol/L in 70%. Compared with the control group, high-dose vitamin D3 supplementation resulted in a decreased trabecular number (regression coefficient β: −0.22; p < 0.01) and lower compression stiffness (B: −3.63; p < 0.05, together with an increase in the bone resorption marker CTX (B: 0.062; p < 0.05). No statistically significant differences were observed between the control and low-dose intervention group. In conclusion, the bolus equivalent of 700 U/day vitamin D3 supplementation in a Western postmenopausal population does not improve distal radius fracture healing and an equivalent dose of 1800 IU/day may be detrimental in restoring bone stiffness during the first 12 weeks of fracture healing. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
998.
Because the cost of managing an expected greater number of adverse reactions when high-osmolality contrast media (HOM) are used could offset the higher material cost of low-osmolality contrast media (LOM), a prospective study was done of 795 inpatients undergoing any of four procedures involving intravascular injection of HOM: cardiac catheterization, peripheral angiography, head computed tomography (CT), or body CT. The resources used in managing HOM-induced adverse reactions were measured, and the costs of these resources were estimated. Four hundred five patients (51%) had adverse reactions. Reactions were grouped into three classes according to their severity. Class 1 (mild) reactions occurred in 358 patients (45%), class 2 (moderate) reactions occurred in 44 patients (6%), and class 3 (severe) reactions occurred in three patients (0.4%). Ninety-nine patients (12%) consumed resources as a result of an adverse reaction. The average cost of these resources per patient undergoing examination was $1.07 to the radiology department, $5.83 to the hospital, and $12.93 to a charge-paying insurer. Mean (+/- standard deviation) cost to the hospital for managing class 1, class 2, and class 3 reactions were $2.52 +/- $5.33, $24 +/- $54, and $910 +/- $749, respectively. By comparison, the difference in material cost of HOM versus LOM ranged from $93 for body CT to $179 for cardiac catheterization. Even if LOM were to induce no adverse reactions, the increased material cost associated with universal substitution of LOM for HOM would be greater than the expected cost of managing adverse reactions when HOM are used.  相似文献   
999.
Human alcohol dehydrogenase (ADH; alcohol:NAD+ oxidoreductase, EC 1.1.1.1) occurs in multiple forms, which exhibit distinct electrophoretic mobilities and enzymatic properties. The homogeneous isoenzymes beta 1 beta 1 and gamma 1 gamma 1 were isolated from livers of Caucasians with "typical" ADH phenotype by double ternary complex affinity chromatography and ion exchange chromatography. The differences between the beta 1 and gamma 1 subunits were determined by structural analysis of all tryptic peptides from the carboxymethylated proteins. The human beta 1 and gamma 1 chains differ at 21 of the 373 positions (5.6%). Ten tryptic peptides account for the differences. All residue substitutions are compatible with one-base mutations and result in largely unaltered properties, but five lead to charge differences. Sixteen substitutions are at positions corresponding to the catalytic domain of the well-known horse enzyme; five correspond to the coenzyme-binding domain. Substitutions adjacent to important regions may correlate with differences in coenzyme binding, substrate specificities, and active-site relationships. The residue replacements between the beta 1 and gamma 1 subunits of human ADH are not identical to the known substitutions between ethanol-active (E) and steroid-active (S) subunits of horse ADH. Thus, the duplication leading to human beta 1 and gamma 1 subunits is separate and different from that leading to equine E and S subunits. Both duplications are likely to have occurred after the ancestral separation of human and equine ADH. Of the 21 residues that are different between beta 1/gamma 1, 13 in gamma 1 but only 6 in beta 1 are identical to those of the horse E chain. This suggests a closer relationship between gamma 1 and E, although beta 1 in man and E in the horse are the subunits recovered in highest yield from liver ADH preparations. Consequently, in these two mammalian species, relative activities of genes for an isoenzyme family appear to be different.  相似文献   
1000.
Lee  KR; Cox  GG; Price  HI; Johnson  JA; Neff  JR 《Radiology》1986,158(1):255-258
Conventional arteriography and intraarterial digital subtraction arteriography (IADSA) were compared in 36 patients with primary bone or soft-tissue tumors of the extremities. The sensitivity of IADSA was at least equal to conventional arteriography for demonstrating normal or abnormal major arteries and feeding arteries, equal to or superior for depicting tumor stains or draining veins, but slightly inferior for revealing minute tumor vessels. An increase of the matrix size from 256 X 256 to 512 X 512 improved these sensitivities. IADSA with 15% diatrizoate contrast material eliminated the contrast material-induced pain in all patients. With a computer-controlled iris setting, an average of 5 minutes of procedure time and 1.7 R of radiation (0.44 mC kg) per examination could be saved. IADSA reduced the cost of an examination by an average of $67. The results indicate that IADSA was diagnostic in all instances and can replace conventional arteriography for the evaluation of extremity tumors.  相似文献   
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