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1.
The study of the effects of morphogenesis at puberty on the Leydig cells in the testis of the young hedgehog and of the subsequent changes due to the seasonal varisations, has been done. Furthermore, the restorative changes induced by the exogenous hormones in the Leydig cells and the related sex organs of the regressed hedgehogs have also been studied. It was observed that the Leydig cells from the undifferentiated mesenchyme cell-like nature in the young hedgehog, develop into an adult form possessing large number of lipids, a well-developed Golgi apparatus, complex mitochondria and extensive smooth endoplasmic reticulum. The depletion of the lipids and other regression associated changes are found in the interstitial Leydig cells but not in those situated under tunica albuginea and the latter probably function as lipid storing cells during regression. Pituitary extract, either alone or in combination, but not testosterone, could restore completely the structure of the regressed Leydig cells. Similarly, the restoration of the complete process of spermatogenesis and the structure and function of the epididymis in the regressed hedgehog was found to be dependent upon the synergistic action of both testosterone and the gonadotrophic hormones. 相似文献
2.
L. H. Iversen † H. Harling‡ S. Laurberg P. Wille-Jørgensen‡ On behalf of the Danish Colorectal Cancer Group 《Colorectal disease》2007,9(1):38-46
OBJECTIVE: We reviewed recent literature to assess the impact of hospital caseload, surgeon's caseload and education on long-term outcome following colorectal cancer surgery. METHOD: We searched the MEDLINE and Cochrane Library databases for relevant literature starting from 1992. We selected hospital caseload, surgeon's caseload and surgeon's education, type of hospital, and surgeon's experience as variables of interest. Measures of outcome were recurrence-free survival and overall survival, and for rectal cancer frequency of permanent stoma. We reviewed the 34 studies according to tumour location: colonic cancer, rectal cancer, or colorectal cancer. We described the studies individually and performed a meta-analysis whenever it was considered appropriate. RESULTS: For colonic cancer, overall survival improved with increasing hospital caseload, odds ratio (OR) 1.22 [95% confidence interval (CI) 1.16-1.28], and surgeon's education. For rectal cancer, overall survival improved with increasing hospital caseload, OR 1.38 (95% CI 1.19-1.60), and, possibly by surgeon' education and experience. Cancer-free survival was strongly influenced by surgeon's education. The colostomy rate was less in high caseload hospitals, OR 0.76 (95% CI 0.68-0.85). For colorectal cancer, overall survival improved with surgeon's education. CONCLUSION: The data have provided evidence that long-term survival following colorectal cancer surgery in general improved significantly with increasing hospital caseload and surgeon's education. 相似文献
3.
Diarrhoeal diseases remain a major cause of mortality and morbidity in developing countries. However, due to lack of funds, supply problems and some inexperience, some laboratories have difficulty identifying a causative agent in stool samples. In the year following the opening of the Shaukat Khanum Memorial Cancer Hospital and Research Centre in Lahore, Pakistan, the microbiology department had not isolated a single enteric pathogen. From January 1996, new culture techniques were introduced, with a resulting increase (10%) in identification of these pathogens. In addition, the introduction of formol-ether concentration made a significant contribution to the number of intestinal parasites seen. This report demonstrates how simple microbiology methods made a difference to the running of the department and, ultimately, to the patients. 相似文献
4.
Kristiansen OP Karlsen AE Larsen ZM Johannesen J Pociot F Mandrup-Poulsen T;Danish IDDM Epidemiology Genetics Group Danish Study Group of IDDM in Childhood 《Scandinavian journal of immunology》2004,59(6):582-591
CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM. 相似文献
5.
G. R. Chalmers P. Bawa 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,116(2):351-358
Short-latency excitatory Ia reflex connections were determined between pairs of human wrist flexor and extensor muscles.
Spindle Ia afferents were stimulated by either tendon tap or electrical stimulation. The activity of voluntarily activated
single motor units was recorded intramuscularly from pairs of wrist flexor or extensor muscles. Cross-correlation between
stimuli and the discharge of the motor units provided a measure of the homonymous or heteronymous excitatory input to a motoneurone.
Homonymous motoneurone facilitation was generally stronger than that of the heteronymous motoneurones. The principal wrist
flexors, flexor carpi radialis (FCR) and flexor carpi ulnaris (FCU), were tightly connected through a bidirectional short-latency
reflex pathway. In contrast, the extensor carpi ulnaris (ECU) and the extensor carpi radialis (ECR) did not have similar connections.
ECU motoneurones received no short-latency excitatory Ia input from the ECR. ECR motoneurones did receive excitatory Ia input
from ECU Ia afferents; however, its latency was delayed by several milliseconds compared with other heteronymous Ia excitatory
effects observed. The wrist and finger extensors were linked through heteronymous Ia excitatory reflexes. The reflex connections
observed in humans are largely similar to those observed in the cat, with the exception of heteronymous effects from the ECU
to the ECR and from the extensor digitorum communis (EDC) to the ECU, which are present only in humans. The differences in
the reflex organization of the wrist flexors versus the extensors probably reflects the importance of grasping.
Received: 19 August 1996 / Accepted: 6 March 1997 相似文献
6.
A. S. Khurana G. S. Bawa Jagdeepak Singh 《Indian journal of otolaryngology and head and neck surgery》1987,39(3):125-126
A rare case of Embryonal Rhabdomyosarcoma of the middle ear and mastoid with distant metastasis in liver and spinal cord is presented. 相似文献
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The pandemic of 2019 novel coronavirus (SARS‐CoV‐2019), reminiscent of the 2002‐SARS‐CoV outbreak, has completely isolated countries, disrupted health systems and partially paralyzed international trade and travel. In order to be better equipped to anticipate transmission of this virus to new regions, it is imperative to track the progress of the virus over time. This review analyses information on progression of the pandemic in the past 3 months and systematically discusses the characteristics of SARS‐CoV‐2019 virus including its epidemiologic, pathophysiologic, and clinical manifestations. Furthermore, the review also encompasses some recently proposed conceptual models that estimate the spread of this disease based on the basic reproductive number for better prevention and control procedures. Finally, we shed light on how the virus has endangered the global economy, impacting it both from the supply and demand side. 相似文献