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411.
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Hemophilic pseudotumor is a rare, but well-known complication of hemophilia occurring in approximately 1–2% of patients with severe forms of the disease [1, 2]. A pseudotumor is a collection of encapsulated blood caused by recurrent hemorrhage in bone or soft tissue. Pseudotumors are classified as soft-tissue or osseous based on their location of occurrence [3]. The pseudotumor itself is painless; however, as it grows it causes increasing compression of adjacent structures, leading to necrosis [2]. Nerve compression or compartment syndrome can result in severe pain. Though the diagnosis is straightforward in individuals with known hemophilia, the occurrence of a pseudotumor in a patient without a known history of hemophilia can be a diagnostic challenge [4]. Although the treatment of bleeding episodes in patients with hemophilia is well established, the treatment of hemophilic pseudotumors is difficult, partly because of their rarity. Surgical resection or drainage, chronic factor replacement therapy, external beam irradiation, and other non-surgical measures have been used to treat hemophilic pseudotumors [5, 6]. We herein report a hemophilic pseudotumor in a patient without a history of hemophilia or bleeding tendency who presented with severe right leg pain initially diagnosed as sciatica.  相似文献   
414.
Objectives

Oral behaviors are activities, like gum chewing, teeth clenching, and biting of objects, that go beyond normal functioning demands and contribute to the onset of temporomandibular disorders (TMD). Somatosensory amplification refers to the tendency to experience somatic sensations as intense, noxious, and disturbing and is related to bodily hypervigilance. Clinical experience suggests that individuals with bodily hypervigilance also present with occlusal hypervigilance and continuously check their occlusion. This study aimed at investigating whether somatosensory amplification and trait anxiety, a characteristic correlated with hypervigilance, are associated with a greater incidence of oral behaviors, and verifying how self-reported facial TMD pain affect this relationship.

Materials and methods

The State-Trait Anxiety Inventory, the Somatosensory Amplification Scale, the Oral Behavior Checklist (OBC), and the TMD-Pain Screener Questionnaire were filled out by 255 University students with self-reported facial TMD pain (PAIN group; 47 subjects, 24.8 ± 4.2 years) and without pain (CTR group; 208 subjects, 26.0 ± 4.8 years) using a web survey.

Results

Trait anxiety, somatosensory amplification, and OBC scores were greater in the PAIN than CTR group (all p < 0.05). Trait anxiety and somatosensory amplification were positively associated with the frequency of oral behaviors, as measured with the OBC (all p < 0.05). A significant effect of the interaction study group*trait anxiety (p = 0.028) on OBC scores was found.

Conclusions

Individuals with greater trait anxiety and somatosensory amplification report more frequent oral behaviors. The relationship between anxiety and oral behaviors is affected by concurrent facial pain.

Clinical relevance

Individuals with increased trait anxiety and concurrent facial pain report more frequent oral behaviors than those without pain. Clinicians should evaluate patients’ anxiety and somatosensory amplification before starting dental treatment.

  相似文献   
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The basis of resistance to oxidative injury was studied in six murine tumor cell lines that differed 54-fold in their resistance to enzymatically generated H(2)0(2). The tumors varied 56.7-fold in their specific activity of catalase, 5.3-fold in glutathione peroxidase (GPO), 3.3-fold in glutathione reductase (GR), and 2.7-fold in glutathione. There was no correlation among the levels of the three enzymes, and tumor cell resistance to lysis by H(2)0(2). However, the logarithm of the flux of H(2)0(2) necessary to cause 50 percent lysis of the tumor cells correlated with their content of glutathione (r = 0.91). The protective role of glutathione was analyzed by blocking GR and GPO, the catalysts of the glutathione redox cycle. This was facilitated by the demonstration that the anti-neoplastic agent 1,3-bis-(2- chloroethyl)-l-nitrosourea (BCNU) was a potent inhibitor of GR in intact tumor cells. BCNU inactivated tumor cell GR with a 50 percent inhibitory dose of 11 μM and a t(l/2) of inhibition of 30 s. Complete inhibition of GR was attained with no effect on GPO or catalase. Tumor cells whose GR was inactivated by BCNU could be lysed by fluxes of H(2)0(2) to which they were otherwise completely resistant. They could be killed by phorbol myristate acetate (PMA)-stimulated, bacilli Calmette-Guerin-activated macrophages in numbers which were otherwise insufficient, and by nonactivated macrophages, which otherwise were ineffective. BCNU-treated target cells were also much more sensitive to antibody-dependent, macrophage-mediated cytolysis. However, such tumor cells were no more sensitive than controls to lysis by alloreactive T cells or by antibody plus complement. Next, we deprived tumor cells of selenium by passage in selenium-deficient mice. GPO was inhibited 85 percent in such cells, with no effect on GR or catalase. Tumor cells with reduced GPO activity were markedly sensitized to lysis by small fluxes of H(2)0(2) or by PMA-stimulated macrophages or granulocytes. In contrast, inhibition of catalase with aminotriazole had no effect on the sensitivity of three tumors to peroxide-mediated lysis, and had modest effects with two others. Thus, the oxidation-reduction cycle of glutathione serves as one of the major defense mechanisms of tumor cells against three related forms of oxidant injury: lysis by fluxes of H(2)0(2), by PMA-triggered macrophages, and by macrophages in the presence of anti-tumor antibody.  相似文献   
417.
The genetic control of the immune response of inbred strains of mice to certain antigens has been demonstrated to be governed by a set of Ir genes linked to the major histocompatibility complex (H-2) of mice (1,2). Until recently, the control was thought to be governed by single, dominant genes, located within the I region of the H-2 complex. Merryman et al. (3) originally demonstrated that the immune response to the synthetic terpolymer L-glutamic acid, L-lysine, L-phenylaline (GL) is under dominant, H-2-linked Ir gene control (4-7). This was shown both by crossing two nonresponder parental strains to produce responder offspring in the F(1) generation, and by the analysis of appropriate recombinant stains of mice. The two complementing genes have been mapped in the IA and IC regions of the H-2 complex, and have been termed β and α, respectively (5,6). Thus, any strain of mouse may contain neither, one, or both genes. Only mice containing both genes are capable of responding to GL. It has been shown using F(1) hybrid and recombinant strains of mice, that the α- and β-genes can complement each other in either the cis (on the same chromosome) or in the trans (on different chromosomes) position (8). In this paper we report the results of studies aimed at answering the question of whether or not the α- and β- genes can complement each other when they are present in different lymphoid cells. To this end we have constructed allophenic mice composed of two nonresponder strains (A and C57BL/6), which show gene complementation in the F(1) generation. Allophenic mice are chimeras containing two cell types coexisting in a “normal” environment. The mice were tested for the specific cellular composition of the two parental cell types and were found to possess a complete range in the relative proportion of the two cell types. This report demonstrates that regardless of the mixture of cell types present in the allophenic mice, none of them were responders to GL. Thus no complementation of the α- and β-genes is seen when the two genes are present in different cells.  相似文献   
418.
The aim of the present study was to formulate a simple chemically defined medium for the in vitro growth of rat two-cell embryos to blastocysts. Embryos from day 2 pregnant rats were retrieved and placed in paraffin oil-covered droplets of "rat two-cell embryo culture medium" (R2ECM) containing combinations of various serum supplements, glucose, L-glutamine, and cultured up to 96 h in a CO(2) incubator. Embryos cultured in the basic medium (R2ECM), as well as those supplemented either with fetal bovine serum (FBS) or male rat serum (MRS) did not develop beyond the two- to four-cell stage. In R2ECM with 0.3% bovine serum albumin (BSA) and 7.5 mM glucose, 44% of embryos reached the blastocyst stage by 96 h in culture, and the blastulation rate increased to about 83% when 1 mM of L-glutamine was added. To evaluate the effects of varying doses of glucose, two-cell embryos were cultured in R2ECM supplemented with 0.3% BSA, 1 mM L-glutamine, and 2.5, 5.0, or 7.5 mM of glucose. The percentage of embryos reaching the blastocyst stage for 2.5, 5.0, and 7.5 mM glucose was 64.6%, 65.3%, and 82.9%, respectively. The present study showed that the modified medium (R2ECM) is a simple chemically defined medium that is capable of supporting in vitro growth of rat two-cell embryos to blastocysts in high proportion (greater than 80%) without the need for change of medium within 96 h of culture.  相似文献   
419.
OBJECTIVE: Epidemiological studies have shown that the prevalence of psychiatric disorders among dermatological patients is high. We aimed at estimating the short-term incidence of psychiatric disorders among patients with skin disease. METHODS: The 12-item General Health Questionnaire (GHQ-12) was used to identify subjects free from psychiatric morbidity at their first dermatological visit. The GHQ-12 was administered again after 1 month during a computer-assisted telephone interview. RESULTS: A total of 277 subjects was included in the study. At the follow-up interview, 21 (7.6%) were found to have significant psychiatric morbidity. Only lack of improvement was associated with increased incidence of psychiatric morbidity (13.6%), with an odds ratio of 3.1 (95% confidence interval 1.2-7.8), after adjustment for gender, age, educational level and clinical severity. CONCLUSIONS: Physicians should devote special attention to the risk of psychiatric complications in patients who have not improved with treatment.  相似文献   
420.
培养临床药师提高合理用药水平   总被引:7,自引:1,他引:6  
吴永佩  颜青 《中国医院》2002,6(8):49-51
医院药学的发展机遇与挑战并存,科技进步、改革的深化,要求医院药学必须转变观念。建议医学院校的药学院(系)逐步改革现行的化学模式的药学教育制度,建立生物医学模式的药学教育制度,开设临床药师专业,开办临床药师专业硕士、博士学位班,制定临床药学管理办法,明确临床药师岗位职责,营造有利于临床药师发展的医院环境。  相似文献   
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