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71.

Introduction

Rectal polypectomy causes thinning (or even perforation) of the rectal wall in addition to thermic injury at the polypectomy site.

Case report

We present a rare case of spontaneous rectal perforation after uncomplicated nerve sparing endoscopic extraperitoneal radical prostatectomy in a patient with a previous history of rectal polypectomy at the perforation site. The patient could be treated conservatively. There was complete healing of the fistula without any effect on functional results. This Conservative therapy for such rectal perforations is indicated if the patient''s general condition remains stable without any signs of infection.

Conclusions

Polypectomy is an important risk factor for rectal perforation during nsEERPE. Adequate time interval should be given to allow healing and avoid adding further thermal wall damage which may obscure healing leading to complications like fistula. Conservative therapy for small missed rectal perforations constitutes an attractive, feasible and non invasive treatment entity. Following this principle we have not faced this complication in following similar cases.  相似文献   
72.

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.  相似文献   
73.

Background

In the adult abdomen of Drosophila, the shafts of mechanosensory bristles point consistently from anterior to posterior. This is an example of planar cell polarity (PCP); some genes responsible for PCP have been identified. Each adult bristle is made by a clone of four cells, including the neuron that innervates it, but little is known as to how far the formation or positions of these cells depends on PCP. The neurons include a single dendrite and an axon; it is not known whether the orientation of these processes is influenced by PCP.

Results

We describe the development of the abdominal mechanosensory bristles in detail. The division of the precursor cell gives two daughters, one (pIIa) divides to give rise to the bristle shaft and socket cell and the other (pIIb) generates the neuron, the sheath and the fifth cell. Although the bristles and their associated shaft and socket cells are consistently oriented, the positioning and behaviour of the neuron, the sheath and the fifth cell, as well as the orientation of the axons and the dendritic paths, depend on location. For example, in the anterior zone of the segment, the axons grow posteriorly, while in the posterior zone, they grow anteriorly. Manipulating the PCP genes can reverse bristle orientation, change the path taken by the dendrite and the position of the cell body of the neuron. However, the paths taken by the axon are not affected.

Conclusion

PCP genes, such as starry night and dachsous orient the bristles and position the neuronal cell body and affect the shape of the dendrites. However, these PCP genes do not appear to change the paths followed by the sensory axons, which must, therefore, be polarised by other factors.
  相似文献   
74.
We report the discovery and the synthesis of novel, potential antipsychotic compounds combining potent dopamine D2 receptor antagonist and serotonin 5-HT1A receptor agonist properties in the same molecule. We describe the structure-activity relationship that lead us to the promising derivative: N-[(2,2-dimethyl-2,3-dihydro-benzofuran-7-yloxy)ethyl]-3-(cyclopent-1-enyl)-benzylamine 16. The latter has high affinity for D2 and 5-HT1A receptors, whereas it possesses only a weak affinity for 5-HT2A sites. In cellular models of signal transduction, 16 behaves as a silent antagonist at rD2 receptors while activating h5-HT1A receptors with an efficacy at least equivalent to that of the prototypical 5-HT1A agonist (+/-)-8-OH-DPAT. These dual actions confer a unique pharmacological profile to the product. In a behavioral model predictive of positive symptoms, 16 has an activity comparable to that of the typical antipsychotic haloperidol, while it is devoid of cataleptogenic effects. Although it produces behaviors characteristic of 5-HT1A receptor activation in rats, these occur at doses 100 times higher than those with (+/-)-8-OH-DPAT. We believe that the relative balance of D2 and 5-HT1A actions in 16 is appropriate, possibly optimal, to ensure superior efficacy and tolerability over existing antipychotic drugs.  相似文献   
75.
The Van Nuys Prognostic Index 1996 (VNPI), based upon tumor size, pathological grade and tumor margins, is a guideline for the treatment of ductal carcinoma in situ (DCIS). It was thought to strongly decrease overtreatment. In 2003, age was added to the index as a fourth prognostic factor. We examined changes in treatment modality after applying the VNPI retrospectively and investigated if the addition of age to the Index causes a shift in treatment. The influence of each prognostic factor on disease-free survival (DFS) was calculated. We performed a retrospective file study of DCIS patients treated between 1985 and 2003 at the University Hospital, Antwerp. Patients were assigned a Van Nuys Score 1996 and 2003. The influence of tumor size, pathological grade, tumor margins and age on DFS was calculated with the Kaplan-Meier method and the log-rank test. We identified 104 DCIS cases with a median follow-up of 36 months. Twelve patients showed recurrence (11.5%), of whom seven were invasive (58%). Seventeen of the 29 women diagnosed before 1997 were undertreated according to the VNPI 1996 and six of them showed recurrence. The remaining three recurrences were correctly treated. Seventy-five patients diagnosed after 1997 were all treated according to the VNPI 1996 and only three had a recurrence. The introduction of age caused no significant shift in treatment modalities. Significant differences in DFS were seen between large (>41 mm) and small (<15 mm) tumors (p = 0.0074), old (>60 years) and young (<40 years) patients (p = 0.024) and Van Nuys Subgroup 2 and 3 (p = 0.04). Tumor margins and pathological grade showed no significant difference in DFS. The VNPI can be a useful tool in the treatment of DCIS. However, this Index is not evidence-based, using a relatively small retrospective series of patients. The validity of the modified VNPI must be prospectively confirmed with large numbers of DCIS patients.  相似文献   
76.
We sought to determine whether the intrinsic pulmonary hypertensive activity of the purported thromboxane A2/prostanoid (TP) receptor antagonist, daltroban, was mediated by TP receptors, using the high efficacy TP receptor agonist, U-46619, and the silent TP receptor antagonist, SQ 29,548. In pentobarbitone-anæsthetized, open-chest rats (n = 4–10 per group), non-cumulative injections of U-46619, dose-dependently increased mean pulmonary arterial pressure (MPAP) with an ED50 (geometric mean with 95% confidence limits in parentheses) of 1.4 (1.1– 2.3) μg/kg i.v.. Daltroban increased MPAP in a bell-shaped manner, with an apparent ED50 [29 (21–35)μg/kg i.v.] being 21 fold less potent than that of U-46619. The maximal pulmonary hypertensive responses evoked by daltroban represented about half those induced by U-46619 (25.4 ± 1.0 vs. 12.7 ± 2 mmHg; P < 0.05 between groups). The TP receptor antagonist SQ 29,548 fully antagonized increases in MPAP evoked by equihypertensive doses of U-46619 (1.25 μg/kg) or daltroban (80 μg/kg). Further experiments were carried out to determine whether daltroban antagonized the pulmonary hypertensive responses evoked by the high efficacy agonist, U-46619, or by itself as receptor theory would predict for a partial agonist. Daltroban (10–2500 μg/kg) antagonized, although not fully, U-46619 (20 μg/kg)-evoked pulmonary hypertensive responses, since prominent intrinsic pulmonary hypertensive effects of daltroban were observed in the same range of doses. Furthermore, in contrast to U-46619 (1.25 μg/kg), daltroban (80 μg/kg) failed to evoke a second pulmonary hypertensive response following a previous injection, as would be expected for a partial agonist. Collectively, the results strongly suggest that daltroban behaves as a partial agonist at TP receptors in the pulmonary vascular bed of the rat in vivo.  相似文献   
77.
78.
Barth syndrome is a metabolic disease characterized by infantile cardiomyopathy, neutropenia and organic aciduria. We report disease evolution in one of the first affected boys to undergo successful cardiac transplantation. CONCLUSION: Although cardiac status stabilized, he developed disabling skeletal myopathy, protracted lymphopenia and--5 y after transplant--fatal Epstein Barr (EBV)-negative T-cell non-Hodgkin's lymphoma.  相似文献   
79.
80.
A 25-year-old HIV-infected African albino woman developed an aggressive Merkel cell carcinoma on her face and at least 10 basal cell carcinomas, mainly on sun-exposed parts of her body. HIV infection, immune deficiency and sun exposure are known risk factors for the development of Merkel cell carcinoma. Chemotherapy and radiotherapy were only temporarily successful. She died shortly after surgery was performed to remove the tumour.  相似文献   
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