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61.
AIM: It has been proposed that gonadotropin-releasing hormone (GnRH) analog administered after testicular damage stimulates the recovery of spermatogenesis. However, GnRH analogs suppress the function of sex accessory organs. In this study, we investigated whether testosterone also stimulates the regeneration of rat spermatogenesis after exposure to busulfan. METHODS: Male Fisher rats were divided into three groups of five each and all rats were treated with busulfan, 25 mg/kg, intraperitoneally at week 0. Group A served as the control. The other two groups received testosterone enanthate, 8 mg/kg, subcutaneous injections at 3 week intervals two times before (group B) or three times after (group C) busulfan. States of spermatogenesis were evaluated by histology and by the number of spermatid nuclei per testis at week 25. RESULTS: The mean percentage of 'recovered' seminiferous tubules plus or minus standard deviation was 10.3 +/- 7.8% in group A and 2.1 +/- 1.2% in group B. In both groups, more than 80% of the tubules remained degenerated. However, testes of group C rats showed an improvement of up to 37.1 +/- 20.5% (P < 0.05). The significant recovery of spermatogenesis was also demonstrated in group C by counting the number of spermatid nuclei per testis ([78.8 +/- 57.5] x 106). However, the count was only (7.6 +/- 13.5) x 106 and (0.52 +/- 1.0) x 106 in group A and B, respectively. CONCLUSIONS: Testosterone administration after severe testicular damage enhanced the regeneration of spermatogenesis in rats. We assumed that supplementary doses of testosterone would be more practical for clinical application than GnRH analogs, because exogenous testosterone maintains androgenicity.  相似文献   
62.
Abstract— The effects of ageing on the pharmacokinetics, renal handling and protein binding of enprofylline were investigated in 6-, 13- and 18-month-old male Fischer 344 rats. Concentrations of enprofylline in plasma and urine were determined by HPLC, and pharmacokinetic parameters were estimated by model-independent methods. No significant differences in the volume of distribution, systemic clearance of enprofylline or urinary recovery of unchanged enprofylline (> 85%) were observed among any of the groups of rats. The dissociation constant and free fatty acid concentration in plasma increased with age. Age-dependent decreases in the systemic clearance for unbound drug were observed, and the volume of distribution for unbound drug tended to decrease with age. The ratio of systemic clearance for unbound drug to the glomerular filtration rate (GFR) decreased with ageing. Ageing was associated with decreases in the apparent maximum capacity of transport (Vmax) (223·33,160·24 and 142·98 μg min?1 kg?1 for 6-, 13- and 18-month-old rats, respectively) and in the tubular secretory intrinsic clearance (Vmax/Km) of enprofylline (75·45, 51·03 and 44·13 mL min?1 kg?1, respectively), while a slight change in the Michaelis-Menten constant (Km) was observed. These results indicate that the mechanism responsible for age-related changes in the disposition and renal handling of enprofylline may be responsible for a decrease in the ability of the tubular anion transport system.  相似文献   
63.
BACKGROUND: The present study was designed to reveal the usefulness of acupuncture for chronic pelvic pain syndrome with intrapelvic venous congestion as evaluated by symptom scores, transrectal ultrasonography (TRUS) and magnetic resonance (MR) venography. METHODS: Ten male patients suffering from non-inflammatory chronic pelvic pain syndrome (NIH category IIIB) with intrapelvic venous congestion were treated using acupuncture. Eight patients had previously received pharmacotherapy, which was unsuccessful. Acupuncture was performed using disposable stainless steel needles, which were inserted into the bilateral BL-33 points and rotated manually for 10 min. The treatment was repeated every week for 5 weeks without other therapeutic maneuvers. Results from TRUS and MR venography, as well as clinical symptoms based on the NIH chronic prostatitis symptom index (NIH-CPSI) and the international prostate symptom score (IPSS), were compared before and after the treatment. RESULTS: No side-effects were recognized throughout the treatment period. The average pain and QOL scores of the NIH-CPSI 1 week after the 5th acupuncture treatment decreased significantly (P < 0.05 and P < 0.01, respectively) compared with the baseline. The maximum width of the sonolucent zone 1 week after the 5th treatment also decreased significantly (P < 0.01, compared with the baseline). Intrapelvic venous congestion demonstrated by MR venography was significantly improved in four patients. CONCLUSION: This study provided novel information concerning the therapeutic effects of acupuncture on non-inflammatory chronic pelvic pain syndrome.  相似文献   
64.
A new oral sustained-release solid-dispersion preparation of cisplatin (cis-diamminedichloroplatinum(II); cisplatin) has been developed for administration to small experimental animals such as mice. This preparation was obtained by formulating cisplatin with the water-insoluble polymer ethylcellulose and with stearic acid in different ratios. In-vitro dissolution studies showed that cisplatin release characteristics were zero-order for the formulation cisplatin–ethylcellulose–stearic acid (1:10:5) and levels equilibrated 7 h after the start of the experiment. The availability of cisplatin from this preparation was evaluated both in rats and mice. The cisplatin preparation (20 mg kg?1) was administered orally to rats and the resulting curve of serum cisplatin levels against time was compared with that obtained after intravenous infusion (20 mg kg?1) to rats. By comparing the areas under serum concentration-time curves (AUCs), the bioavailability of cisplatin was estimated to be 31%. The mean residence time (MRT) of cisplatin solid dispersion was 6.13 ± 0.43 h, whereas the MRT of cisplatin administered by intravenous infusion was 3.89 ± 0.05 h. Serum cisplatin levels were maintained above 0.3 mg mL?1 (believed from our clinical studies to be the minimum effective concentration) for 24 h. The curve of serum cisplatin level against time suggested that cisplatin was released from the solid dispersion preparation in a sustained-release fashion. Similar levels were also maintained in mice for 24 h. The MRT of the cisplatin preparation was 10–16 h in mice, which is longer than that obtained after oral administration of the physical mixture. The serum free-cisplatin concentration was determined to be 0.10 mg mL?1 in mice serum in which the total cisplatin concentration was 0.30 mg mL?1. The free fraction of cisplatin in mice serum was the same as that in human patient serum. Pathological examination showed that this new sustained-release oral cisplatin preparation did not have any side effects on the gastrointestinal tract. These results suggest usefulness of this new solid-dispersion preparation for oral cisplatin therapy in lung cancer patients.  相似文献   
65.
Forty episodes of induced ventricular tachycardia in the late myocardial infarction period (4-6 days old) were analyzed in 12 dogs in an attempt to identify the possible mechanisms for the termination of reentry tachycardia. Multiple epicardial and endocardial composite electrograms were recorded in and around the central ischemic zone of the infarction. During tachycardia, the earliest site of activation was identified in the epicardial surface of the border or normal zone immediately adjacent to the ischemic zone in 36 of the 40 episodes, suggesting efferent epicardial spread from the site of the activity. In four instances, the efferent pathways were directed to the endocardial surface. Four distinct patterns of activation sequences were observed during spontaneous termination: (a) a shift of the efferent pathways from epicardial to endocardial site (19 instances); (b) a change of the efferent pathways within the endocardium (4 instances); (c) a shift of the earliest site of activation between the left and right ventricles (9 instances); and (d) no apparent change in the epicardial efferent pathways (4 instances). In four other instances, ventricular tachycardia deteriorated into ventricular fibrillation. In patterns (a) and (c), a shift of the efferent pathways resulted in a more rapid and homogeneous activation of the border and normal zone epicardium. These changes were associated with cessation of delayed or continuous activity in the ischemic zone epicardium, resulting in termination of tachycardia.  相似文献   
66.
Between October 1989 and September 1993, 245 cases of poliomyelitis visited the Department of Pediatrics, Civil Hospital Karachi, Pakistan. The majority of them were between 6 months and 2 years of age and the epidemic occurred during the hot season. The dominant serotype was polio type 1. All of the polioviruses isolated from the patients were wild type. Virological studies also disclosed that enteroviruses other than polioviruses were prevalent among healthy children as well as diarrheal and polio patients. Serodiagnosis by poliovirus-specific immunoglobulin M antibody tests using the capture enzyme-linked immunosorbent assay method were in good agreement with the results of virus isolation. The present study demonstrated that Pakistan is a region endemic for wild poliovirus and more aggressive preventive measures are needed to eradicate poliomyelitis from the region.  相似文献   
67.
We report a case of a large right atrial myxoma. With the useof transoesophagal echocardiography, several cysts were idntifieldwithin the tumour and necrotic tissue was differentiated frommyxomatous tissue according to its echo-level. Transoesophagealechocardiography was very useful for the precise diagnosis ofcardiac tumour and demonstration of the inner structure.  相似文献   
68.
The effect of coping on the caregiver of elderly patients with dementia   总被引:1,自引:1,他引:0  
Abstract Ninety-eight caregivers of elderly patients with cognitive impairment were surveyed by questionnaires in order to examine the relationship between their coping strategies and subjective burden. Confrontative coping and avoidance coping were significantly associated with their burden. The severity of cognitive impairment and the behavioral problems of the patients were also significantly associated with the caregivers' burden. However, a multiple regression analysis suggested that the caregivers' coping strategies may be more important than the patients' condition in terms of the effects on the burden.  相似文献   
69.
BACKGROUND: Transabdominal ultrasonography was used to study the bladder neck morphology in women with urethral syndrome or stress urinary incontinence, in order to determine the ultrasonographic findings of these conditions. METHODS: A total of 210 female patients with a normal bladder, asymptomatic trigonitis, urethral syndrome, and stress incontinence were studied. The mucosal thickness around the bladder neck, the length of the anterior base plate of the bladder, and the anteroposterior vesical wall angle (APVA) at the bladder neck were measured on sagittal transabdominal vesical ultrasonograms with the patient in the supine position. RESULTS: Patients with asymptomatic trigonitis or urethral syndrome had thicker mucosa around the bladder neck than the subjects with a normal bladder, and the subjects with stress incontinence had normal mucosa. The APVA was 158 +/- 17 (mean +/- SD) degrees in the subjects with a normal bladder. It was smaller in symptomatic patients and decreased to 109 +/- 10 degrees in those with conservative therapy-resistant incontinence. The anterior edge of the vesical base plate was visible approximately 2 cm from the bladder neck in subjects without incontinence, while it tended to be absent in patients with incontinence and an APVA of less than 126 degrees. CONCLUSION: A small APVA appears to reflect bladder neck descent, while a small APVA without a visible anterior base plate edge may reflect hypotonia of the vesical base plate. Transabdominal vesical ultrasonography with the patient in the supine position provides useful information and can be carried out as a routine examination in female patients with micturition disorders.  相似文献   
70.
Abstract We report a patient, a 30-year-old male Japanese-Brazilian migrant construction worker, suffering from excessive daytime sleepiness for at least 6 months. Electroencephalogram recordings during his waking states showed that 10-Hz and 60-µV alpha activity was present prominently in the occipital regions. From the multiple sleep latency test, it was found that stages 1–2 NREM sleep episodes appeared repetitively without any REM episodes, and that the mean sleep latency was 10.2 min. These findings support the diagnosis that this patient suffers from subwakefulness syndrome.  相似文献   
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