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21.
22.
Winberg  CD; Sheibani  K; Krance  R; Rappaport  H 《Blood》1985,66(4):980-989
Peripheral T cell lymphomas (PTCLs) form a morphologically heterogeneous group of non-Hodgkin's lymphomas that are generally considered to have immunophenotypes associated with mature T cells, usually those of helper T cells. We now describe and correlate the clinical, morphological, immunologic, and cell-kinetic findings based on the evaluation of eight tissue samples obtained at various times from a 13-year-old girl with PTCL. The early morphological expressions of this patient's PTCL were those of diffuse mixed-cell lymphoma and focal large-cell lymphoma (LCL) evolving from the histologic picture of an atypical immune response (AIR). These morphological findings were associated with an immature T cell immunophenotype associated with cortical thymocytes--namely, sheep erythrocyte rosette (sER)+, T11+, Leu-2a+, Leu-3a+, HLA-DR+, OKT6-, OKT9+, OKT10+--and with cell-kinetic findings that showed no evidence of aneuploidy and few cells in S phase. Diffuse pleomorphic LCL developed, which was associated with further dedifferentiation of the neoplastic T cells to the immunophenotype sER-, T11+, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10- and with cell-kinetic findings that demonstrated a distinct aneuploid population and a dramatic increase in the percentage of cells in the S phase. The immunophenotype of the PTCL at the time of the patient's death was T11-, Leu-2a-, Leu-3a-, HLA-DR+, OKT6-, OKT9+, OKT10-, an immunophenotype indistinguishable from that of a non-B non-T cell lymphoma. The immunologic findings in this case also suggest that an AIR in some cases may represent a prelymphomatous state or may be a morphological expression of PTCL. These observations indicate that PTCLs may be characterized by rapidly changing clinical, morphological, immunologic, and cell kinetic findings which are best evaluated by multidisciplinary studies.  相似文献   
23.
The effect of dorsal raphe nucleus (DRN) electrical stimulation on response properties of layers IV and V barrel cortical neurons was studied. To assess the receptive field characteristics of cortical neurons, responses of neurons were recorded following the displacement of principal and adjacent whiskers individually or in a condition test paradigm. Then neuronal responses to the displacement of whiskers were analyzed following DRN stimulation at 0, 50, 100, 200 and 400 ms inter-stimulation intervals. Considering On responses, DRN stimulation suppressed the response magnitude of layer V neurons to principal whisker deflection, while it slightly increased that of layer IV neurons (not statistically significant). The response latency of layer IV neurons increased when DRN was stimulated 200 or 400 ms before principal whisker deflection, while the response latency of layer V was not changed. DRN stimulation had no effect on either magnitude or latency of neuronal response to the adjacent whisker deflections. We observed a decrease in the inhibitory effect of the adjacent whisker deflection on the magnitude of neuronal response to the principal whisker deflection in layer IV when DRN was stimulated 200 ms before the principal whisker deflection. Off responses did not show any significant effect of DRN stimulation. Our results suggest a modulating role for DRN in processing of the incoming information into barrel cortex. This effect might be location dependent.  相似文献   
24.
Our purpose in this study was to determine whether tumor DNA content is a prognostic factor independent of other standard clinical and histologic parameters in squamous cell carcinoma (SCC) of the head and neck region. Tumor DNA content was determined in 76 patients with primary resectable SCC of the oral cavity, larynx, or pharynx who were treated from 1978 to 1984 at the City of Hope. In addition, we measured various clinical and pathologic parameters in all patients. In comparison to patients with diploid SCC, those with aneuploid SCC had significantly decreased relapse-free and overall survival rates (p less than 0.001 for both). A Cox regression analysis demonstrated that tumor DNA content was a prognostic factor independent of all clinicopathologic features examined. By regression analysis, it was the single most important prognostic factor in determining relapse and death from SCC (p less than 0.001 for both).  相似文献   
25.
Phorbol 12-myristate 13-acetate (PMA) and phorbol 12,13-dibutyrate (PDBU) are known to translocate protein kinase C (PKC) and to induce superoxide anion (O2-.) production in human neutrophils. They are thus currently used to probe the role of PKC in O2-. production. We show here that under certain conditions, O2-. production induced by PMA is not associated with a decrease in cytosolic PKC activity, whereas these two events are associated after PDBU stimulation. (1) In the presence of extracellular calcium (1 mM), O2-. production was related to the concentration of PMA. PMA induced O2-. production at all the concentrations studied, but this was not associated with a decrease in cytosolic PKC levels up to 5 ng/ml PMA (50% maximum O2-. production). (2) Under PDBU stimulation, even at very low O2-. production levels, cytosolic PKC decreased and the decrease as well as the O2-. production were related to the concentration of PDBU. (3) For a given decrease in cytosolic PKC, O2-. production induced by PMA was much greater than that induced by PDBU. (4) In calcium-free medium, O2-. production induced by low concentrations of PMA (up to 5 ng/ml) was lower than that observed in the presence of 1 mM calcium, whereas modifications of cytosolic PKC activity were similar. (5) Cytochalasin B had no effect on PMA-induced O2-. production, regardless of the calcium content of the medium, and had no effect on the decrease in cytosolic PKC. On the contrary, following PDBU stimulation, cytochalasin B increased O2-. production, regardless of the medium, but induced a larger decrease in cytosolic PKC when Ca2+ was present. (6) Preincubation of PMN with 100 microM H-7 (1-(5-isoquinolinylsulfonyl)-2-methylpiperazine) before stimulation with PMA or PDBU led to similar inhibition of O2-. production whatever the degree of decrease in cytosolic PKC activity. These findings show that, in contrast to PDBU, O2-. production induced by PMA is not always related to cytosolic PKC activity.  相似文献   
26.

Objective

Acute seizure attack is a stressful experience both for health care personnel and parents. These attacks might cause morbidity and mortality among patients, so reliable methods to control the seizure preferably at home should be developed. This study was performed to measure the time needed to control seizure attacks using intranasal midazolam compared to the common treatment (intravenous diazepam) and to evaluate its probable side effects.

Methods

This study was conducted as a not blind randomized clinical trial among 60 patients coming to Imam Ali Hospital, Zahedan, Iran. The patients were 2 months to 15 years old children coming to our emergency department suffering from an acute seizure episode. Intranasal midazolam was administered 0.2 mg/kg equally dropped in both nostrils for case group and intravenous diazepam was administered 0.3mg/kg via IV line for control group. After both treatments the time needed to control the seizure was registered by the practitioner. Pulse rate and O2 saturation were recorded at patients’ entrance and in minutes 5 and 10 after drug administration.

Findings

The time needed to control seizure using intranasal midazolam (3.16±1.24) was statistically shorter than intravenous diazepam (6.42±2.59) if the time needed to establish IV line in patients treated by intravenous diazepam is taken into account (P<0.001). The readings for O2 saturation or heart rate did not indicate a statistically significant difference between two groups of patients either at entrance or 5 and 10 minutes after drug administration.

Conclusion

Considering the shorter time needed to control acute seizure episodes compared to intravenous diazepam and its safety record, intranasal midazolam seems to be a good candidate to replace diazepam, as the drug of choice, in controlling this condition.  相似文献   
27.
In early postnatal life, sensory inputs deeply influence development as well as function of the brain. Plasticity of synaptic transmission including its experimentally induced form, long‐term potentiation (LTP), is affected by sensory deprivation in neocortex. This study is devoted to assess if dark rearing and a dark phase synthesized hormone melatonin influence LTP in the hippocampus, an area of brain involved in learning and memory. In vivo experiments were carried out on two groups of 45‐days‐old male Wistar rats kept in standard 12‐h light/dark condition [light reared (LR) tested during the light phase] or in complete darkness [dark reared (DR)] since birth to testing. Each group, in turn, was divided to two, vehicle‐ and melatonin‐treated, groups. Stimulating the Schaffer collaterals of CA3 area of hippocampus extracellular postsynaptic potentials (EPSPs) were recorded in the CA1 area. Having the stable baseline responses to the test pulses, the hippocampus was perfused by either vehicle or 2 μg melatonin and EPSPs were recorded for 30 min. Then, for induction of LTP, the tetanus was applied to the Schaffer collaterals and the field potentials were pooled for 120‐min post‐tetanus. The light deprivation resulted in a significant augmentation in the amplitude of baseline responses. Also, we observed a melatonin‐induced increase in amplitude of the baseline recordings in either LR or DR animals. Tetanic stimulation elicited LTP of EPSPs in both LR and DR groups, robustly in the former where it lasted for about 90 min. Generally, melatonin inhibited the production of LTP in the two groups especially in the LR animals leading to a noticeable depression. We concluded that higher level of neuronal activity in the DR rats gives rise to a lower level of LTP. Weaker effect of melatonin on blocking the potentiation of post‐tetanus EPSPs in the DR rats may be the result of a desensitization of melatonin receptors due to chronically increased levels of this hormone in the visually deprived rats. © 2009 Wiley‐Liss, Inc.  相似文献   
28.
This article describes the histological and mucin histochemical properties of the small intestine of the Persian squirrel (Sciurus anomalus). This species is widely distributed in the Middle East and can be found as a companion animal. The histological studies revealed that the plicae circulares were not visible in the tunica mucosa. The maximum height and width of the villi were observed in the duodenum, which then decreased toward the ileum. The muscularis mucosa was scattered, whereas the tunica submucosa was composed of dense connective tissue. The lymphatic nodules were seen in the submucosa of the distal part of the jejunum and ileum, and Brunner’s glands were embedded in the initial portion of the duodenum. The tunica muscularis was significantly thicker in the ileum, and the circular muscle layer was thicker than the longitudinal muscle layer throughout the entire length of the small intestine. The mucin histochemistry, which was examined using the periodic acid-Schiff (PAS) and alcian blue (AB) (pH 1.0 and 2.5) and also PAS–AB (pH 2.5) and aldehyde fuchsin-AB (pH 2.5) techniques coupled with methylation and saponification reaction for some sections, showed that the small intestine mucous content included both carboxylated and sulfated acidic mucins with few neutral mucins. The results of this study contribute to the knowledge of the histological and histochemical characteristics of the gastrointestinal tracts of exotic mammals and provide data for comparison with other mammals.  相似文献   
29.
Neurologic sequelae remain a common and destructive problem in patients with acute kidney injury. The objective of this study was to evaluate the possible neuroprotective effect of erythropoietin (EPO) on motor impairments following bilateral renal ischemia (BRI) in two time points after reperfusion: short term (24 h) and long term (1 week). Male Wistar rats underwent BRI or sham surgery. EPO or saline administration was performed 30 min before surgery (1000 U/kg, i.p.). Explorative behaviors and motor function of the rats were evaluated by open field, rotarod, and wire grip tests. Plasma concentrations of blood urea nitrogen (BUN) and creatinine (Cr) were significantly enhanced in BRI rats 24 h after reperfusion. BRI group had only an increased level of BUN but not Cr 1 week after reperfusion. Impairment of balance function by BRI was not reversed by EPO 24 h after reperfusion, but counteracted 7 days after renal ischemia. Muscle strength had no significant differences between the groups. BRI group had a decrease in locomotor activity, and EPO could not reverse this reduction in both time points of the experiment. Although EPO could not be offered as a potential neuroprotective agent in the treatment of motor dysfunctions induced by BRI, it could be effective against balance dysfunction 1 week after renal ischemia.  相似文献   
30.
Tumor DNA content in resectable, primary colorectal carcinoma.   总被引:8,自引:1,他引:8       下载免费PDF全文
Tumor DNA content was measured in patients with colorectal carcinoma in order to determine whether tumor ploidy was a prognostic indicator independent of standard clinical and pathologic characteristics. One hundred forty-seven patients were analyzed who had their primary resectable colorectal carcinomas resected with curative intent from 1974 to 1981. Aneuploid colorectal cancers (i.e., tumors with abnormal DNA content) tended to be less well-differentiated, to invade the serosa or extend beyond, and to have lymph node metastases rather than diploid tumors (i.e., tumors with normal DNA content). A significantly increased rate of recurrent disease was demonstrated in patients with aneuploid tumors as opposed to those with diploid tumors (46.7% vs. 4.8%, respectively [p less than 0.001]). In addition, patients with aneuploid tumors exhibited a significantly decreased disease-free and overall survival in comparison with patients with diploid colorectal carcinomas. A Cox regression analysis demonstrated that tumor DNA content was the single most important factor in predicting recurrence or death from colorectal carcinoma.  相似文献   
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