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71.

Negative implications of exposure to violence on health and well-being of youth have been observed and studied worldwide and especially in Israel. Youth in the Western Negev of the country have been exposed to missile and terror attacks for more than a decade. However, implications of such prolonged exposure have not been fully studied. This study is aimed at the implications of exposure to such conditions on youth in the town of Ofakim in the Negev. A focus group was conducted with youth following the Israeli Defense Forces’ “Protective Edge” response to continued attacks from Gaza (July–August 2014). Focus group participants reported high stress levels during the operation that resulted in an increase of substance use including alcohol, tobacco, cannabis, and synthetic cannabis-like substances (e.g., “Nice Guy,” “Spice,” and “Black Mamba”) and changes in eating and sleeping behavior. The Ofakim resilience center served as a shelter for participants providing for them with physical and emotional comfort. Staying in the “shelter” used for protection against missile attack promoted youth resilience. Exposure to violence has a significant impact on the health and well-being of young people and others. A secure receptive facility that provides trust and support can serve as an important moderator of the negative impact of emergency conditions. From the results reported in this article, further research is needed to fully assess the long-term effects of stress conditions including the use of cannabis and synthetic cannabis-like substances among youth and other residents in the Western Negev.

  相似文献   
72.

Background

Essential tremor (ET) is one of the most common movement disorders of adults, characterized by postural and kinetic tremor. With drug treatment only partially efficient, new treatments are being developed.

Objectives

The goal of this study was to demonstrate the feasibility of non-thermal focused-ultrasound (FUS) to induce tremor-suppression in an ET rat model.

Methods

Harmaline-induced tremor rats were treated with FUS along the inferior olivary (IO) system. EMG was recorded continuously during treatment in order to quantify FUS-induced tremor suppression. T2-weighted MRI was performed immediately following treatment and periodically thereafter.

Results

FUS treatment at an intensity of 27.2?W/cm2 (Isppa) induced significant reduction of tremor in 12 out of 13?ET rats. Tremor frequency was reduced from 6.2?±?2.8 to 2?±?1?Hz, p?<?0.0003. In 6 of the 12 responding rats, tremor was completely suppressed. Response duration was 70?±?61s, on average.FUS induced motor response, depicted as movement of the tail and/or the limbs synchronized with the FUS sonication, was also demonstrated both in ET rats and in naïve rats when treated in the medulla oblongata region.

Conclusions

These results demonstrate the feasibly for obtaining significant tremor reduction or tremor suppression induced by non-thermal, non-invasive, reversible focused-ultrasound.  相似文献   
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Phenylhydrazine (PHZ) exposure is used to study in vitro red cell aging mechanisms dependent on Hb oxidation. The effect of PHZ on normal neonatal red blood cells was studied in unseparated blood and after separation into light and heavy cells. PHZ caused more extensive morphologic changes in neonatal than in adult red blood cells. PHZ exposure of neonatal cells caused less reduced glutathione depletion than in adult cells. Although we found the same total amount of oxidized Hb in both cells, a well-defined oxidation product of Hb was demonstrated by M?ssbauer spectra only in neonatal cells. This oxidation product was not methemoglobin but a trivalent, high-spin iron compound. All neonatal cell populations were more sensitive to PHZ than were adult ones, as demonstrated by the presence of Heinz bodies at low PHZ concentration, which did not affect adult cells. These studies demonstrate greater sensitivity of neonatal cells to PHZ in all density-separated populations.  相似文献   
76.
This study investigated the possible oxidative effect of vitamin K3 (menadione) and Vitamin K1 (Konakion) on neonatal erythrocytes by controlled in vitro exposure. Menadione caused only mild morphological changes and did not decrease ATP levels. However, it oxidized intracellular hemoglobin to methemoglobin in neonatal cells more than in adult cells. Reduced glutathione contents were higher in neonatal cells, but less available for antioxidant protection. Konakion did not increase methemoglobin levels in newborn infants after a prophylactic injection. In vitro exposure to Konakion did not affect reduced glutathione and ATP levels, nor did it oxidize hemoglobin. However, extensive morphological changes were observed, attributed to the effect of its solvent. Therefore, it seems that menadione, which is no longer administered to newborns, causes oxidative stress in neonatal cells whereas Konakion, the current vitamin K1, does not, either in in vitro studies or by therapeutic administration.  相似文献   
77.
Zmora S  Glicklis R  Cohen S 《Biomaterials》2002,23(20):4087-4094
The pore architecture in 3-D polymeric scaffoldings plays a critical role in tissue engineering as it provides the framework for the seeded cells to organize into a functioning tissue. In the present paper, we investigate the effect of freezing regime on the pore microstructure in 3-D alginate scaffolds, fabricated by the freeze-dry method. The scaffolds have shown isotropic pore structure, when the calcium crosslinked alginate solutions were slowly frozen at -20 degrees C, in a nearly homogenous cold atmosphere; the pores were spherical and interconnected. In contrast, when the cooling process was performed in liquid nitrogen or oil bath, where a temperature gradient was formed along the freezing solution, two main regions of pore structure were noted; at the interface with the cooling medium, small spherical pores were seen and above them a region with elongated pores. The different pore shape affected the compressibility of the scaffolds, while it had no effect on albumin diffusion. Rat hepatocytes seeded within the scaffolds were arranged according to the their pore shape. In scaffolds with elongated pores, the cells were lining along the pores, thus forming lines of interacting cells. In the scaffolds with the isotropic spherical pores, the hepatocytes clustered into spheroid-like aggregates. Thus, it appears that pore shape can modulate hepatocyte morphogenesis.  相似文献   
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Severe nutritional deficiencies developed in four infants from a new vegan religious community. They had received breast milk until the age of 3 months; thereafter, breast milk was supplemented with or replaced by extremely low caloric-density preparations. All of the infants had profound protein-caloric malnutrition, severe rickets, osteoporosis, and vitamin B12 and other deficiencies. One infant died, while the three others had an uneventful recovery. After discharge of the infants from the hospital, the community responded well to a modification of the infants' diet, which did not violate their vegetarian philosophy. However, they refused to give their infants vitamin B12 on a regular basis.  相似文献   
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