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81.

Introduction

It has been reported that posttraumatic stress disorder (PTSD) is associated with secondary spouse/partner (S/P) emotional distress and relationship violence.

Objective

To investigate the relationships between PTSD, S/P emotional distress and relationship violence among police recruits using a prospective design.

Methods

Two hypotheses were tested in 71 S/Ps: (1) Police officer reports of greater PTSD symptoms after 12 months of police service will be associated with greater secondary trauma symptoms among S/Ps; (2) Greater secondary trauma symptoms among S/Ps at 12 months will be associated with S/P reports of greater relationship violence.

Methods

71 police recruits and their S/Ps were assessed at baseline and 12 months after the start of police officer duty. Using linear and logistic regression, we analyzed explanatory variables for 12 month S/P secondary traumatic stress symptoms and couple violence, including baseline S/P variables and couple violence, as well as exposure and PTSD reports from both S/P and officer.

Results

S/P perception of officer PTSD symptoms predicted S/P secondary traumatic stress. OS/P secondary trauma was significantly associated with both total couple violence (.34, p = .004) and S/P to officer violence (.35, p = .003).

Conclusions

Although results from this relatively small study of young police officers and their S/Ps must be confirmed by larger studies in general populations, findings suggest that S/P perception of PTSD symptoms may play a key role in the spread of traumatic stress symptoms across intimate partner relationships and intimate partner violence in the context of PTSD.  相似文献   
82.
The search for novel insect repellents has been driven by health concerns over established synthetic compounds such as diethyl-m-toluamide (DEET). Given the diversity of compounds known from frog skin and records of mosquito bite and ectoparasite infestation, the presence of mosquito repellents in frogs seemed plausible. We investigated frog skin secretions to confirm the existence of mosquito repellent properties. Litoria caerulea secretions were assessed for mosquito repellency by topical application on mice. The secretions provided protection against host-seeking Culex annulirostris mosquitoes. Olfactometer tests using aqueous washes of skin secretions from L. caerulea and four other frog species were conducted to determine whether volatile components were responsible for repellency. Volatiles from Litoria rubella and Uperoleia mjobergi secretions were repellent to C. annulirostris, albeit not as repellent as a DEET control. The demonstration of endogenous insect repellents in amphibians is novel, and demonstrates that many aspects of frog chemical ecology remain unexplored.  相似文献   
83.
The food habits of strap-toothed whales ( Mesoplodon layardii ) were examined in detail using stomach contents from 14 stranded whales found on South African and New Zealand coasts. Although a few unidentified fish otoliths and crustacean remains were found in two of these stomachs, 24 species of oceanic squids (some of which occur at a great depth) accounted for 94.8% of counted prey items ( n = 232). Histioteuthis sp. and Taonius pavo were the predominant prey species (25.0 and 17.2% by number, 21.4 and 19.9% by mass, respectively). The presence of sub-Antarctic squid species suggested a northward migration to South African waters in late summer/autumn. Prey sizes were compared between males with fully grown strap-teeth and females/immature males without erupted teeth, using dorsal mantle lengths (DML) and weights of squids estimated from beak measurements. Although females/immature males ate longer squids than males, there was no significant difference in the estimated weights of squids eaten by the two groups. The presence of fully-erupted teeth in adult males, therefore, did not seem to influence the size of prey ingested, even though an adult male could only open its jaws about half as wide as a female. In general, the sizes of cephalopods eaten by strap-toothed whales were not significantly different from those eaten by smaller odontocetes, such as spotted dolphins and dwarf sperm whales, but were significantly smaller than those eaten by larger odontocetes, such as false killer, long-finned pilot, Cuvier's beaked, and southern bottlenose whales.  相似文献   
84.
The chaperonin GroEL assists protein folding through ATP-dependent, cooperative movements that alternately create folding chambers in its two rings. The substitution E461K at the interface between these two rings causes temperature-sensitive, defective protein folding in Escherichia coli. To understand the molecular defect, we have examined the mutant chaperonin by cryo-EM. The normal out-of-register alignment of contacts between subunits of opposing wild-type rings is changed in E461K to an in-register one. This is associated with loss of cooperativity in ATP binding and hydrolysis. Consistent with the loss of negative cooperativity between rings, the cochaperonin GroES binds simultaneously to both E461K rings. These GroES-bound structures were unstable at higher temperature, dissociating into complexes of single E461K rings associated with GroES. Lacking the allosteric signal from the opposite ring, these complexes cannot release their GroES and become trapped, dead-end states.  相似文献   
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As bald eagle populations recover, defining major sources of mortality provides managers important information to develop management plans and mitigation efforts. We obtained data from necropsies on 1,490 dead bald eagles (Haliaeetus leucocephalus) collected in Michigan, USA, conducted from 1986 to 2017 to determine causes of death (COD). Trauma and poisoning were the most common primary COD categories, followed by disease. Within trauma and poisoning, vehicular trauma (n = 532) and lead poisoning (n = 176) were the leading COD subcategories, respectively. Females comprised a greater number of carcasses for most COD diagnoses. The proportion of trauma and poisoning CODs significantly increased in the last few years of the study in comparison to a select few years at the beginning. Trauma CODs were greater in autumn months during whitetail deer (Odocoileus virginianus) breeding and hunting seasons and in February, when aquatic foraging is unavailable and eagles are likely forced to scavenge along roadsides. Poisoning CODs were greatest in late winter and early spring months, when deer carcasses containing lead ammunition, which are preserved by the cold weather, also become a supplemental food source. The major infectious disease CODs, West Nile virus and botulism (Clostridium botulinum type E), were more prevalent during summer months. We recommend moving road-killed carcasses, especially white-tailed deer, from the main thoroughfare to the back of the right-of-way, and the transition from lead ammunition and fishing tackle to non-toxic alternatives to decrease these main anthropogenic sources of mortality for bald eagles, and other scavenger species. © 2020 The Wildlife Society.  相似文献   
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We report for the first time, to our knowledge, that the N-terminal loop (N_loop) of amylin (islet amyloid polypeptide (IAPP) residues 1–8) forms extremely long and stable non-β-sheet fibers in solution under the same conditions in which human amylin (hIAPP) forms amyloid fibers. This observation applies to the cyclic, oxidized form of the N_loop but not to the linear, reduced form, which does not form fibers. Our findings indicate a potential role of direct N_loop-N_loop interactions in hIAPP aggregation, which has not been previously explored, with important implications for the mechanism of hIAPP amyloid fiber formation, the inhibitory action of IAPP variants, and the competition between ordered and disordered aggregation in peptides of the calcitonin peptide family.  相似文献   
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