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1.
The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo , perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 × 104 and 5 × 104 cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.  相似文献   
2.
BACKGROUND: Intravesical oxybutynin chloride with hydroxypropylcellulose (HPC) (modified intravesical oxybutynin) has been reported to be effective for treatment of overactive bladder. We reported the short-term effects of modified intravesical oxybutynin previously. In the present article, we detail the results of a 3-year follow-up study of patients from our previous analysis and report the efficacy and side-effects of modified intravesical oxybutynin. METHODS: Modified intravesical oxybutynin (5 mg/10 mL, twice a day) was applied for more than 3 years to six neurogenic overactive detrusor patients (three men and three women, average age 53.3 years) who were not satisfied with oral anticholinergic agents or the other therapy. A cystometogram (CMG) was performed before, 1 week after and 3 years after the start of modified intravesical oxybutynin treatment. We evaluated the patient's satisfaction of this treatment after 4 weeks and again after 3 years. We compared the patients' answers before and after the therapy (excellent, good, fair, unchanged and worse). We also monitored systemic and topical side-effects in these patients during this period. RESULTS: CMG studies showed that two of six patients no longer exhibited uninhibited contraction 1 week after the treatment and that the cystocapacity of patients before, 1 week after and 3 years after the initial modified intravesical oxybutynin was 129.7 +/- 19.4, 283.5 +/- 40.4 and 286.8 +/- 38.1 mL, respectively. For the evaluation of patients' satisfaction with this treatment, four patients considered the therapy excellent and one patient described it as good after both 4 weeks and after 3 years. Two patients dropped out of the study; one developed left ureteral cancer (2.25 years) and the other developed ileus (1.5 years). Dry mouth and acute cystitis were observed in both patients. CONCLUSION: Modified intravesical oxybutynin is an effective and relatively safe option of therapy for overactive bladder patients. However, this therapy requires careful observation for emergent side-effects.  相似文献   
3.
Efficacy and safety of laparoscopic surgery for pheochromocytoma   总被引:4,自引:0,他引:4  
OBJECTIVE: Laparoscopic surgery for primary aldosteronoma and Cushing's syndrome is well established. We report on our experiences with laparoscopic adrenalectomy for pheochromocytoma, and assess the efficacy and safety of the laparoscopic approach. METHODS: Between April 1998 and April 2003, a total of 23 patients underwent laparoscopic adrenalectomy for pheochromocytoma at Chiba University Hospital and Yokohama Rosai Hospital, Japan. We compared the surgical outcomes of these patients with those of 106 patients with adrenal tumors due to other pathologies who underwent laparoscopic adrenalectomy during the same period. RESULTS: The mean tumor size of pheochromocytoma was 4.96 cm. Mean operative time was 192.7 min, and mean estimated blood loss was 130 mL. Neither mean operative time nor mean estimated blood loss was greater for patients with pheochromocytoma. Intraoperative hypertension (systolic blood pressure > 180 mmHg) occurred in 39.1% (9/23) of patients with pheochromocytoma. During the follow-up period, there were no mortalities or recurrences of endocrinopathy. CONCLUSIONS: Laparoscopic adrenalectomy for pheochromocytoma is a safe and minimally invasive procedure.  相似文献   
4.
5.
A morphological approach to cell dynamics is usually difficult, since routine preparative techniques for electron microscopy always induce artifacts due to cessation of the blood supply into organs. An in vivo cryotechnique followed by the freeze-substitution method probably reduces such problems. It was applied for examining the pulmonary alveoli of BALB/c mice in vivo. The following ultrastructural features were revealed. (1) A surfactant layer provided a continuous covering to the alveolar epithelium. (2) Pleural epithelial cells, alveolar cells and endothelial cells contained many small vesicles and pits. In the alveolar epithelium, they were often localised near microtubules. (3) Typical lamellar structures in large alveolar epithelial cells were rarely detected. (4) Circulating erythrocytes with various shapes were observed in branching blood capillaries. (5) A close association between erythrocytes and the endothelium was seen at the peripheral alveolar septum. Such ultrastructural arrangements may be appropriate for the physiological functions of the pulmonary alveoli, such as exchanges of gases or materials in vivo.  相似文献   
6.
Abstract  Gastrointestinal stromal tumor (GIST) is the most frequent non-epithelial neoplasm in the gastrointestinal tract. GIST has received much attention both for its clinical significance and biological nature, while the retroperitoneal condition identical to GIST has been rarely described. Presented herein is a case of GIST arising from the retroperitoneum in a 67-year-old man. The solid tumor measuring 4 cm was uncovered in the retroperitoneum, between the abdominal aorta and inferior vena cava, on computed tomography. The patient underwent surgical excision of the tumor. Histological examination showed proliferating spindle cells in the clearly demarcated tumor; immunoreactivity for Kit and CD34 in tumor cells confirmed the diagnosis of GIST. The histological origin of GIST is suggested to be gastrointestinal pacemaker cells, because they share specific immunoreactivity for CD117/Kit, which is also relevant to pathogenesis of GIST. The present case was a rare primary GIST in the retroperitoneum with typical immunopathological features.  相似文献   
7.
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   
8.
Abstract— Inhibitory effects of β-amyrin palmitate in locomotor activity of mice were studied by combining this compound with α-adrenergic agonists or antagonists and a dopaminergic agonist. β-Amyrin palmitate (2·5, 5·0 and 10·0 mg kg?1, i.p.) decreased locomotor activity of mice in a dose-dependent manner. It enhanced hypoactivity of mice treated with clonidine (0·025 mg kg?1, i.p.) and antagonized hyperactivity produced by phenylephrine (40 μg, i.c.v.). The inhibitory action of β-amyrin palmitate was not affected by yohimbine (1·5 mg kg?1, i.p.), but was potentiated by prazosin (0·75 mg kg?1, i.p.). When combined with a dopaminergic agonist, apomorphine (2·0 mg kg?1, i.p.), β-amyrin palmitate (5·0 and 10·0 mg kg?1, i.p.) did not affect locomotor stimulation produced by apomorphine. These results suggest that β-amyrin palmitate might inhibit α1-adrenoceptors.  相似文献   
9.
BACKGROUND: A school urinary screening (SUS) system has been conducted for 30 years in Japan, but the cross-sectional data have never been reported or analyzed. The purpose of the present study was to analyze the data epidemiologically. METHODS: All elementary and junior high school children in public school in Tokyo who had SUS performed by the Tokyo Health Service Association from 1974 to 2002 (approx. 400,000-600,000 children per year) were involved. The cross-sectional data were analyzed with Pearson's correlation coefficient. RESULTS: During the first 10 years of SUS, the prevalence of abnormal urinalysis in both the first and second screenings varied widely, and the result of the second screening was affected by that of the first screening. The results of both first and second screening were highly correlated with the prevalence of hematuria, especially microhematuria, in both elementary and junior high school children. They were also correlated with the prevalence of proteinuria in junior high school children. Important factors that affected the prevalence of hematuria and/or proteinuria were reagent strips and sampling method of urinalysis. CONCLUSIONS: In order to validate SUS, attention should be paid to quality controls of the screening method, such as the selection of reagent strips, and the participants should be instructed to strictly adhere to the sampling method.  相似文献   
10.
The aggregation of human erythrocytes induced by four kinds of immunoglobulin preparations was examined by a low shear rheoscope. After removing anti-A+ and anti-B+ activities contaminated in all preparations by incubating with erythrocytes of different blood groups, the facilitating effect on the rouleau formation of erythrocytes was compared: (i) The effect of polyethyleneglycol-treated preparation was the same in A+-, B+-, AB+- and O+-erythrocytes. (ii) Sulfonation did not affect the velocity of rouleau formation. (iii) Some of pepsin-treated preparations showed the strongest facilitation for A+-, B+- and AB+-erythrocytes, but the facilitation was much weaker for O+-erythrocytes. The others showed the weak facilitation for all types of erythrocytes (especially O+-erythrocytes). (iv) Plasmin treatment markedly decreased the velocity of rouleau formation of AB+- and O+-erythrocytes, but was not of A+- and B+-erythrocytes.  相似文献   
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