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191.
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function.  相似文献   
192.
This study evaluates the morphological and phenotypic changes that occur in squamous cell carcinoma of the head and neck when local infusions of interleukin-2 (IL-2) are given. Twelve patients were treated with a range of doses of IL-2 (3 × 103 to 3 × 106 international units/day) by continuous intra-arterial infusion for 10 days. Biopsies of the tumour were taken pre- and 48 h post-therapy, snap-frozen, cut, and examined histologically and immunocytochemically. Local infusions of IL-2 increase the numbers of antigen-presenting Langerhans cells (CDIa-positive) and infiltrating lymphocytes, predominantly of the CD3 and CD4 (T-helper) phenotypes. Locally infused IL-2 results in the expression of MHC (major histocompatibility complex) class II antigens on the surface of the tumour cells, capillary and post-capillary endothelial cells, and peri-tumoural macrophages. Intratumoural NK (natural killer) cells and CD8-positive (T-cytotoxic) infiltrating lymphocytes were not increased by this therapy and CD25 (IL-2 receptor) was only increased in those patients treated at the lower does levels. The system of intra-arterial cytokine infusion into head and neck tumours developed in this study is a useful model to examine the biological effects of cytokines, since in vivo they are mainly produced and act locally, Furthermore, the infused tumours are easily accessible to biopsy. The results from studies such as this may influence the design of tumour-targeted cytokine gene therapy programmes.  相似文献   
193.
Serological grouping of Treponema hyodysenteriae   总被引:2,自引:0,他引:2  
Two Australian isolates of Treponema hyodysenteriae which did not fit within the current serological grouping system for these bacteria were examined by agarose gel double immunodiffusion tests (AGDP). Isolate Vic1 was serologically unique, and we propose that it becomes the type organism for a new sixth serological group of T. hyodysenteriae (Group F). Isolate Q1 was unusual in that lipopolysaccharide (LPS) extracted from it reacted strongly in AGDP with serum raised against the type organism for serogroup D (A1), and also weakly with serum raised against the type organism for serogroup B (WA1). The nature of this cross-reactivity was examined by using cross-absorbed antisera in AGDP, and by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis. The pattern of serological cross-reactivity between Q1, A1 and WA1 was complex and was not fully defined, but the isolate Q1 apparently shared low molecular weight 'serogroup' LPS antigens with A1, and shared higher molecular weight LPS antigens with WA1. On this basis Q1 was designated as belonging to serogroup D, although it was recommended that this be qualified as D (B) to indicate the presence of weak cross-reactivity with serogroup B. Such serological cross-reactivity may have significance in relation to the development of immunity to T.hyodysenteriae. Isolate Q1 may be a potentially useful organism for vaccine development because of its ability to induce a good serological response to LPS of treponemes from both serogroups D and B.  相似文献   
194.
Certain features of head-injured patients admitted to the Chang Gung Memorial Hospital in Taiwan during the period 1977 to 1987 were reviewed. The most common causes of injury were motorcycle accidents (56.3%) and street accidents with pedestrian injury (29.47%). The age groups with the greatest incidence of injury were aged 16-20 years, 21-25 years, and 25-30 years. The pedestrian group involving the highest incidence of injury was less than 10 years of age. Overall mortality was 17.26%. The injured pedestrian group had the highest mortality (19.1%). Initial clinical assessment was recorded using the Glasgow Coma Scale. Head-injured patients with a GCS less than 8 had a mortality in the injured pedestrian group of 46%, whereas the mortality rate in the motorcycle accident group was 41%. Additional features studied were time of occurrence of injury and pattern of injury. Information gathered from this study would suggest the need to establish a Head Injury Prevention Program in Taiwan. This of course implies major cooperation among the providers of health care delivery, the medical profession, legislators, and the government at all levels.  相似文献   
195.
In a period of 2 years 7 months, we performed heat probe (HP) thermocoagulation in 153 cases of massive peptic ulcer hemorrhage. The male/female sex ratio was 125/28. The average age was 57.6 +/- 1.3 years (mean +/- SEM; range, 17 to 88). There were 69 cases (45.1%) of spurting hemorrhage, 50 cases (32.7%) of oozing hemorrhage, and 34 cases (22.2%) of nonbleeding visible vessels. Seventy-seven patients (50.3%) were in shock before therapy. After therapy we obtained initial success in 147 cases (96.1%). Rebleeding episodes occurred in 23 patients (15.6%) within 1 month after therapy. Nineteen patients received a second therapy, and treatment in 15 of these cases (78.9%) was ultimately successful. Finally, treatment in 142 cases (92.8%) was ultimately successful. The duration of hospitalization was 6.3 +/- 0.4 days (mean +/- SEM). After discharge all patients were followed at the outpatient department for at least 1 month. Sixty-seven patients were followed endoscopically for at least 2 to 3 months after therapy. Fifty-six patients (83.6%) had a healed scar at the previous bleeding site 2 months after therapy, and 62 patients (92.5%) had a healed scar 3 months after therapy. We conclude that HP thermocoagulation is an ideal and reliable modality of therapeutic endoscopy in arrest of massive peptic ulcer hemorrhage. HP thermocoagulation may become the first choice of therapy for massive peptic ulcer bleeding in the near future.  相似文献   
196.
197.
It is well known that long-term use of steroids plays a decisive role in the development of glucose intolerance and diabetes mellitus (DM). Deflazacort, an oxazoline derivative of prednisolone, has been introduced as a potential substitute for conventional steroids in order to ameliorate glucose intolerance. We initiated a randomized study of conversion from prednisone to deflazacort in kidney transplantation (Tx) recipients presenting with pre-Tx or post-Tx DM to ascertain whether or not the switch to deflazacort would ameliorate the diabetic state. Forty-two recipients in the conversion group were compared with 40 patients on prednisone (the control group) in a prospective manner. The dose reduction of insulin or oral blood glucose-lowering agents, the adequacy of glucose control, and the development of side effects were the criteria for evaluating outcome. In the conversion group, patients were switched to deflazacort at a dose ratio of 6 mg deflazacort to 5 mg prednisone. During the mean follow-up period of 13.2 months, neither graft dysfunction nor acute rejection developed in the conversion group. Improvement in blood glucose control in the conversion group was noted. When the conversion group was stratified into pre- or post-Tx DM, promising effects were clearly evident in the post-Tx DM patients. More than 50 % dose reduction of blood glucose-lowering agents was possible in 42.3 % of post-Tx DM patients. In conclusion, it was readily possible to control blood glucose better in post-Tx DM recipients without seriously affecting the immunosuppressive activity after conversion to deflazacort. Received: 20 August 1996 Received after revision: 25 November 1996 Accepted: 6 December 1996  相似文献   
198.
We report MRI and angiographic findings of an unusual giant arachnoid granulation in the left sigmoid sinus in a boy with headache. Its signal intensity was lower than that of cerebral cortex on T1-weighted images and higher on T2 weighting, mimicking dural sinus thrombosis. Received: 17 February 1997 Accepted: 17 February 1997  相似文献   
199.
200.
We have shown earlier that nicotinic agonists induce the release of noradrenaline from chick sympathetic neurons in culture in two ways: (a) by activating the postsynaptic nicotinic receptors on nerve cell bodies, giving rise to spreading electrical activity and opening of voltage operated calcium channels in neuronal processes; (b) by activating the presynaptic nicotinic receptors on neuronal processes. In the present work, we investigated the contribution of various pathways to the observed Ca2+ influx and subsequent noradrenaline release. Sympathetic neurons in culture were stimulated either by the nicotinic agonist dimethylphenylpiperazinium or electrically, in the presence or absence of tetrodotoxin and of specific blockers of calcium or nicotinic channels, and the effects on [Ca2+]i in the area of neuronal processes and on noradrenaline release were measured. Under control conditions, the N-type channel blocker ω-conotoxin (0.1 μmol/1) diminished the release of noradrenaline and the increase of intraterminal Ca2+ by 48% and 55%, respectively, whereas the L-type channel blocker (+)Bay k 8644 (1 μmol/1) diminished the release of noradrenaline by 25% and the increase of [Ca2+]i by 39%. The P-type channel blocker ω-agatoxin (0.3 μmol/1) had no effect. The effects of the L-type channel ligands were complex and could only be explained on the assumption that, at high concentrations, these drugs also act as nicotinic antagonists. Tetrodotoxin blocked the Ca2+ response evoked by electrical stimulation whereas DMPP applied in the presence of tetrodotoxin still evoked an increase of [Ca2+]i and the release of noradrenaline (27% and 30% of control without tetrodotoxin, respectively). These residual responses were not blocked by any of the calcium channel blockers used or by their combination. Apparently, a substantial part of the influx of Ca2+ induced by the activation of presynaptic nicotinic receptors is not carried by the N-, L- or P-type channels and probably occurs directly via the open channels of nicotinic receptors.  相似文献   
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