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1.
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
2.
Pastore LM  Carter RA  Hulka BS  Wells E 《Maturitas》2004,49(4):292-303
OBJECTIVE: To examine the prevalence and correlates of self-reported urogenital symptoms (dryness, irritation or itching, discharge, dysuria) among postmenopausal women aged 50-79. DESIGN: A cross-sectional analysis based on n=98,705 women enrolled in the US-based Women's Health Initiative observational study and clinical trials. Urogenital symptoms, symptom severity (mild, moderate, severe), and all covariates were self-reported through questionnaires at enrollment. Prevalence rates of each urogenital symptom were examined and logistic regression was used to identify potential correlates. RESULTS: Prevalence rates for each symptom were: dryness, 27.0%; irritation or itching, 18.6%; discharge, 11.1%; and dysuria, 5.2%. Four factors were correlated with two or more symptoms: Hispanic ethnicity (adjusted odds ratio (AOR)=2.1-3.1 versus white women across all symptoms), obesity (AOR=2.2 severe discharge versus none, AOR=3.6 severe irritation/itching versus none), treated diabetes (pills or shots) compared to no diabetes (AOR=2.4 severe dysuria versus none, AOR=3.2 severe irritation/itching versus none), and vaginal cream HRT/ERT compared to those who never used HRT/ERT (AOR=4.4 severe dryness versus none, AOR=4.6 severe irritation/itching versus none). Factors not associated with the symptoms included sexual activity, age, years since menopause, current smoking, marital status, gravidity, and natural versus surgical menopause. CONCLUSIONS: This is the first report to document urogenital symptoms by race/ethnicity among an exclusively postmenopausal population. We found an elevated prevalence of urogenital symptoms among women who are Hispanic, obese, and/or diabetic. Confirmation of our findings in these subgroups, and, if confirmed, analysis on why these populations are at greater risk, are areas for future research.  相似文献   
3.
Cocaine users consistently develop working memory (WM) impairments but the mediating molecular mechanisms are unknown so far. Recent evidence suggests that the serotonin (5-HT) system is altered by chronic cocaine use, while also being involved in WM processing. Thus, we investigated the effects of genetic variations impacting 5-HT activity and of peripheral 5-HT transporter (5-HTT) mRNA expression on WM performance in cocaine users and stimulant naive controls. Two hundred twenty participants (126 cocaine users, 94 controls) were assessed with visuospatial, spatial, and verbal WM tasks, genotyped for the length polymorphism in the promoter region of the 5-HTT (5-HTTLPR), the variable number of tandem repeats in the second intron of the 5-HTT (VNTR In2), two single-nucleotide polymorphisms (rs4570625 and rs1386497) in the tryptophan hydroxylase-2 (TPH2) gene and quantified for peripheral 5-HTT mRNA expression in whole-blood samples. Several significant gene × environment interactions between 5-HT genotypes and cocaine use on WM emerged: in cocaine users, the long/long (5-HTTLPR), 9+10/9+10 (VNTR In2) and C/C (TPH2 rs1386497) genotypes were risk alleles for WM impairments, whereas in healthy controls these polymorphisms were associated with improved WM performance. Analogously, high 5-HTT mRNA levels were associated with worse executive WM performance in cocaine users but with increased performance in controls. These gene × environment interactions suggest that the 5-HT system has an important role in the development of cognitive deficits in chronic cocaine users. Hence, pharmacological compounds targeting 5-HT neurotransmission might be promising for the treatment of cognitive deficits in cocaine dependence.  相似文献   
4.
Cocaine users consistently display cognitive impairments. However, it is still unknown whether these impairments are cocaine-induced and if they are reversible. Therefore, we examined the relation between changing intensity of cocaine use and the development of cognitive functioning within 1 year. The present data were collected as part of the longitudinal Zurich Cocaine Cognition Study (ZuCo2St). Forty-eight psychostimulant-naive controls and 57 cocaine users (19 with increased, 19 with decreased, and 19 with unchanged cocaine use) were eligible for analysis. At baseline and after a 1-year follow-up, cognitive performance was measured by a global cognitive index and four neuropsychological domains (attention, working memory, declarative memory, and executive functions), calculated from 13 parameters of a broad neuropsychological test battery. Intensity of cocaine use was objectively determined by quantitative 6-month hair toxicology at both test sessions. Substantially increased cocaine use within 1 year (mean +297%) was associated with reduced cognitive performance primarily in working memory. By contrast, decreased cocaine use (−72%) was linked to small cognitive improvements in all four domains. Importantly, users who ceased taking cocaine seemed to recover completely, attaining a cognitive performance level similar to that of the control group. However, recovery of working memory was correlated with age of onset of cocaine use—early-onset users showed hampered recovery. These longitudinal data suggest that cognitive impairment might be partially cocaine-induced but also reversible within 1 year, at least after moderate exposure. The reversibility indicates that neuroplastic adaptations underlie cognitive changes in cocaine users, which are potentially modifiable in psychotherapeutical or pharmacological interventions.  相似文献   
5.
Social interaction deficits in drug users likely impede treatment, increase the burden of the affected families, and consequently contribute to the high costs for society associated with addiction. Despite its significance, the neural basis of altered social interaction in drug users is currently unknown. Therefore, we investigated basal social gaze behavior in cocaine users by applying behavioral, psychophysiological, and functional brain-imaging methods. In study I, 80 regular cocaine users and 63 healthy controls completed an interactive paradigm in which the participants’ gaze was recorded by an eye-tracking device that controlled the gaze of an anthropomorphic virtual character. Valence ratings of different eye-contact conditions revealed that cocaine users show diminished emotional engagement in social interaction, which was also supported by reduced pupil responses. Study II investigated the neural underpinnings of changes in social reward processing observed in study I. Sixteen cocaine users and 16 controls completed a similar interaction paradigm as used in study I while undergoing functional magnetic resonance imaging. In response to social interaction, cocaine users displayed decreased activation of the medial orbitofrontal cortex, a key region of reward processing. Moreover, blunted activation of the medial orbitofrontal cortex was significantly correlated with a decreased social network size, reflecting problems in real-life social behavior because of reduced social reward. In conclusion, basic social interaction deficits in cocaine users as observed here may arise from altered social reward processing. Consequently, these results point to the importance of reinstatement of social reward in the treatment of stimulant addiction.Cocaine dependence is a chronically relapsing disorder defined by uncontrolled and compulsive drug use (1). Despite severe negative consequences including disrupted social relationships, loss of employment, and somatic and psychiatric illnesses, an addicted person’s life is often centered around the drug of choice and activities related to it (2). Therefore, drug use is classified as a major social, legal, and public health problem (3). After cannabis, cocaine is the second most prevalent illegal drug in the United States and Europe (4, 5), with a lifetime prevalence among young adults of 6.3% in Europe (15- to 34-y-olds) (4) and 13.3% in the United States (18- to 25-y-olds) (5).Social cognition and social support for drug users are of great clinical relevance, as they have been reported to influence onset of drug use and development of substance use disorders, and treatment success in patients with substance use disorders (6, 7). Impairments in social cognition may augment the risk of social isolation, aggression, and depression, likely supporting the vicious circle of drug use (8). Additionally, impaired social cognition may contribute to the decay of social relationships in addicted patients (9) with negative consequences for treatment success given that higher social support predicted longer abstinence duration (10). Furthermore, no efficient pharmacological treatment for cocaine addiction is currently available (11), and treatment approaches such as cognitive behavioral therapy rely, at least in part, on the emotional responsiveness and social abilities of drug users (12). Previous results suggest that cocaine users (CUs) show impairments in different facets of social cognition, particularly in emotional empathy, mental perspective taking, and emotion recognition in prosody, which are related to deficits in real-life social behavior such as fewer social contacts and more criminal offenses (13, 14). Furthermore, in money distribution games, CUs act more self-servingly and less altruistically than stimulant-naïve controls (15). Volkow et al. (9) postulated that neuroadaptations in the reward systems of drug users (e.g., ventral striatum and orbitofrontal cortex) alter reward processing such that the value of the abused drug is enhanced and concurrently the value of nondrug rewards, including social interaction, is reduced. Consequently, general social competence might become impaired and promote antisocial and criminal behavior. This may explain why social consequences of drug use (e.g., imprisonment or familial problems) do not prompt drug-addicted people to quit using the drug as well as how they contribute to increased drug use and transition from recreational drug use to addiction (9). However, whereas altered processing of monetary rewards has been reported in CUs (16), social reward processing has not been studied yet, neither on the psychological nor the neural level. Therefore, it remains elusive whether CUs (i) show behavioral differences to reward stemming from social interactions and, if so, (ii) which neural adaptations within reward circuitry underlie these potential changes in social interaction behavior.An essential part of social interaction is the phenomenon of “social gaze,” which has two aspects: Gaze can be used by the gazing person as a deictic cue to manipulate the attention of others, and can be read out by observers as a hint toward attentional focus of the gazing person (17). Both aspects can converge in joint attention (JA), which is a central element of social interaction (18) and is established when a person follows the direction of another person’s gaze so that both attend to the same object (19). Engagement in JA is considered to reflect our understanding of another person’s point of view (20). The capacity of JA emerges at 8–12 mo of age (21) and is predictive for later language learning (22) and the development of more advanced social skills such as mental perspective taking (e.g., the attribution of intentions and goals to others, also known as theory of mind) (23). Impaired JA is a core symptom of autism spectrum disorders (24).To test for social gaze differences between CUs and healthy controls (HCs), we applied a paradigm designed to capture the reciprocal and interactive nature of JA (25) (Fig. S1), where participants engage in an online interaction with an anthropomorphic virtual character in real time. Compared with self-initiated nonjoint attention (NJA; i.e., if the counterpart does not follow one’s gaze but rather pays attention to another object), self-initiated JA (i.e., if the counterpart follows one’s own gaze) is perceived as more pleasurable and associated with stronger activation of reward-related brain areas in healthy controls (25). This rewarding nature of JA might underlie the human motivation to engage in the sharing of experiences that emerges in early childhood (22, 25).It has been suggested that changes in social reward processing might underlie alterations in social behavior and cognition in CUs (9). Here we conducted two studies assessing JA processing, which constitutes an elegant approach to investigate basic social interaction patterns related to social reward processing (25), in CUs and stimulant-naïve HCs by means of behavioral, psychophysiological, and functional brain-imaging methods. In study I, a large sample of relatively pure CUs with few psychiatric comorbidities (n = 80) and stimulant-naïve HCs (n = 63) completed an interactive JA task (25) while valence and arousal ratings, error scores, reaction time, and pupil size were obtained. Pupil dilation provides an objective index of affective processing (26, 27). Based on the observations obtained in study I, we further investigated the neural correlates of the blunted emotional response to social gaze in subsamples of 16 CUs and 16 HCs using functional magnetic resonance imaging (fMRI) during an abridged version of the paradigm (study II). We hypothesized that altered emotional responses to JA are accompanied by less pronounced activation in reward-related brain areas of CUs.  相似文献   
6.
Platinum-based materials are widely known as the most utilized and advanced catalysts for hydrogen evolution reaction. For this reason, several studies have reported alternative methods of incorporating this metal into more economical electrodes with a carbon-based support material. Herein, we report on the performance of pencil graphite electrodes decorated with electrochemically deposited platinum nanoparticles as efficient electrocatalysts for hydrogen evolution reaction. The electrodeposition of platinum was performed via pulsed current electrodeposition and the effect of current density on the electrocatalytic activity was investigated. The obtained electrodes were characterized using cyclic voltammetry, while the electrocatalytic activity was assessed through linear sweep voltammetry. Field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy were utilised to gain an insight into surface morphology and chemical analysis of platinum nanoparticles. The best performing electrocatalyst, at both low and high current densities, was characterized by the highest exchange current density of 1.98 mA cm−2 and an ultralow overpotential of 43 mV at a current density of 10 mA cm−2. The results show that, at low current densities, performances closest to that of platinum can be achieved even with an ultralow loading of 50 µg cm−2 Pt.  相似文献   
7.
The purpose of this study was to determine the extent to which women's roles are associated with their symptom reporting and their illness behavior. Data were obtained from 259 married women residing in a probability sample of households in a single community. A positive and statistically significant relationship was found between the number of a woman's role responsibilities and the number of symptom complexes she reported. The best multivariate model to explain the variance in symptom-complex reporting included two variables related to the woman's role demands, having an ill spouse and having three or more children. Role density had only modest effects on illness behavior. Women who were employed or who had an ill child were significantly less likely to cut down on their activity because of symptoms than were women with neither responsibility. Women who had children of preschool age were more likely to consult the lay network for their symptoms than were women whose children were older. Family pressures seem to be more important in the generation of symptoms than the woman's employment status. Women's roles had minimal effect on their illness behavior.  相似文献   
8.
Sterilization by cryosurgery a report of animal fertility studies   总被引:1,自引:0,他引:1  
  相似文献   
9.
We present a profile of the people who use ambulatory services, their reasons, the settings, and at what cost, for a community probability sample of 2,147 adults. The panel design was based upon two interviews four weeks apart; 37% of the sample (804 persons) recalled one or more visits to an ambulatory care setting in the previous four weeks. Symptoms of an illness were responsible for more than 75% of these visits; a physician was seen at 88% of visits, and the most frequent setting visited was the private practice office (91%). Although only a small proportion of the total number were visits to a nurse or physician's assistant, such visits were more convenient in terms of travel and waiting time, and the charges were only half those of the physician visits. There were also differences in visit charges for the general practitioners as compared with specialists.Dr. Daly is a medical student at the University of North Carolina School of Medicine, Chapel Hill, North Carolina 27514. Dr. Hulka is Associate Professor, Department of Epidemiology, University of North Carolina. The project upon which this publication is based was performed pursuant to grant HS00026-05 from the National Center for Health Services Research to the Department of Epidemiology, University of North Carolina. Please send reprint requests to Dr. Hulka.  相似文献   
10.
The sterilization procedures most widely employed in the U.S. and newer methods which hold promise are reviewed. Abdominal Pomeroy tubal ligation, the most commonly used method, is usually done within 48 hours after delivery. A small incision ate. A knuckle of each fallopian tube is ligated and then resected. The cut ends of the tubes retract from each other when the suture absorbs and become sealed by a peritoneal covering. Local or general anesthesia may be used. nimally prolonged. Postoperative morbidity is 2-4% and a reported failure rate of less than 1%. Following Caesarean section, the Irving procedure is used most often. In this method the tubes are double ligated and bedded in the uterine musculature and the distal ends are buried beneath the broad ligament. As an interval procedure, the Pomeroy method or fimbriectomy may be done using the vaginal approach. Pelvic erus prevent this method from being used. igation is combined with first trimester abortion the morbidity is increased. Laparoscopy, culdoscopy, and hysteroscopy are recent advances. To use these methods, special training is needed and the required equipment is 2-puncture method and general anesthesia are preferred. An alternative to coagulation of the tubes is the application of clips. The new spring-loaded clips appear to be most promising. With culdoscopy each tube ligated, cut, and returned to its normal position. Tantalum clips may be used to occlude the tubes. This operation requires a good deal of time to learn but can be done as an outpatient procedure. Pelvic cult. Postoperative infection may follow in 2-10% of cases. In using the hysteroscopic technique, after dilatation of the cervix the hysteroscopic sleeve is introduced and the uterine cavity A cautery probe is introduced into each uterotubal junction and electrocoagulation done. Scar tissue later blocks the tubes. The equipment is expensive and special training is re are numerous contraindications to this method. Hysterectomy for sterilization is a drastic measure. Quinacrine hydrochloride instilled into the uterine cavity is 90% effective in preventing pregnancy. Other sclerosing agents cements, as gelatin-resorcinol-formilin have been used to promote tissue ingrowth to seal fallopian tubes. The choice of procedure for each woman varies according to her life situation and specific needs. seem to offer any advantages over the postpartum Pomeroy tubal ligation. Hysterotomy and tubal ligation are a combination which sometimes seems favorable. Counseling for sterilization is important and complications. problems.  相似文献   
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